Ribbon Microphones

[[email protected]]

I have often wondered why Ribbon mics sound good on Brass and
persussion because they are not fast enough to react to the transients
and therefore get more of a resonant signal compared to the transient.
Kinda like a compressor set with a slow attack time: the signal is too
fast for the gear to see it?
Any thoughts?
kevin

www.kevindoylemusic.com

[Don Pearce]

On 26 Aug 2006 13:27:46 -0700, wrote:

>I have often wondered why Ribbon mics sound good on Brass and
>persussion because they are not fast enough to react to the transients
>and therefore get more of a resonant signal compared to the transient.
>Kinda like a compressor set with a slow attack time: the signal is too
>fast for the gear to see it?
>Any thoughts?
>kevin
>
I think you are talking nonsense. The speed of response to a transient
is determined by the high frequency response limit. This is just as
good in a ribbon (if not better) as any other type of microphone. And
a ribbon is quite likely to be rather less resonant than any other
microphone as it is mass-controlled throughout the audio band - there
is no resonant peak at the upper mid range.

As for signals being too fast for a microphone to see them, how could
that be? All the speed that matters in a signal is found within the
audible band. A microphone that responds to that band has sufficient
speed by definition.

Now - what are you talking about?

d

--
Pearce Consulting
http://www.pearce.uk.com

[Mike Rivers]

wrote:
> I have often wondered why Ribbon mics sound good on Brass and
> persussion because they are not fast enough to react to the transients
> and therefore get more of a resonant signal compared to the transient.

Nope.

Since the makers of new large condenser mics already had the "vocal"
mic market sewed up, the new ribbon mic manufacturers needed another
good reason for people to buy their mics. Nobody took "brass" yet, so
they grabbed it.

A good ribbon mic will sound good on guitars, vocals, banjos, reeds,
whatever you like. A bad ribbon mic will sound just as bad on brass as
any other bad mic.

[[email protected]]

wrote:
> I have often wondered why Ribbon mics sound good on Brass and
> persussion because they are not fast enough to react to the transients
> and therefore get more of a resonant signal compared to the transient.
> Kinda like a compressor set with a slow attack time: the signal is too
> fast for the gear to see it?
> Any thoughts?
> kevin
>
> www.kevindoylemusic.com

Your first sentence doesn't really make sense to me, but it seems to
fall into the same general category as the usual asumptions "Condensor
mic's always sound better than dynamic mic's" which is simply not true.
There's nothing about ribbon mic's that make them any better on brass
or percussion than a dynamic or a condensor. And there's an infinite
variety of _other_ applications where a particular ribbon mic could be
the perfect choice. I've had great results from ribbons used for drums,
violins, guitar amps, vocals, etc.

Let me give you a useful tip if you find yourself recording horns and
percussion on a regular basis. Since you're in Canada look around for a
used Yamaha MZ-204 and a MZ-205. Up there you'll find them at a
reasonable price and they're surprisingly great mic's in many
applications, particularly horns and percussion. There's a lot more of
those mic's drifting around up there (and in Europe) than in the USA.
Also, have you tried a Sennheiser 421 or EV RE-20. All the mic's I've
mentioned are relatively inexpensive and just might give you great
results. Try not to stay married to the idea that a ribbon is always
the best choice.

[Willie K. Yee, MD]

On 26 Aug 2006 14:58:20 -0700, "Mike Rivers" >
wrote:

>A good ribbon mic will sound good on guitars, vocals, banjos, reeds,
>whatever you like. A bad ribbon mic will sound just as bad on brass as
>any other bad mic.
>

Until the recent Chinese and Russian imports, how many "bad" ribbon
mics are there? My thinking is that ribbons were difficult enough to
make at all, that all that were made were of pretty good quality, with
the exception of an occassional dud, which can happen with anything.

Bad ribbons? Names, please.

[Roy W. Rising]

wrote:
> I have often wondered why Ribbon mics sound good on Brass and
> persussion because they are not fast enough to react to the transients
> and therefore get more of a resonant signal compared to the transient.
> Kinda like a compressor set with a slow attack time: the signal is too
> fast for the gear to see it?
> Any thoughts?
> kevin
>
> www.kevindoylemusic.com

Fuzzy thinking must not be dignified with a drawn out explanation. Just
take a look at the Beyer M130 and M160 curves to see what a good ribbon can
do. Let me add ... an RCA 77DX does not qualify as a good ribbon. ~ Roy

--
~ Roy
"If you notice the sound, it's wrong!"

[Mike Rivers]

Willie K. Yee, MD wrote:

> Until the recent Chinese and Russian imports, how many "bad" ribbon
> mics are there?

Well, there's the Beatles-made-famous Reslo. And I wonder how bad the
modern ones really are. There's been a Russian one around for several
years which may be essentially the same one that Electro-Harmonix is
selling now. I know Scott doesn't think too highly of the Nady ribbon
mic, but they have a bunch of them now. Maybe they finally lucked out.

> My thinking is that ribbons were difficult enough to
> make at all, that all that were made were of pretty good quality, with
> the exception of an occassional dud, which can happen with anything.

Actually, they aren't that hard to make, certainly no harder to make
than condenser mics, once you know how they're supposed to work, but
they require some parts that you can't make in a basement machine shop
(like the magnets) and they require a step-up transformer that either
means expensive or curmmy-sounding due to a crummy transformer. But one
thing that the foreign makers don't seem to have a good handle on yet
is the mechanical (including acoustic) design.

[[email protected]]

I read an article By Bruce Swedien who mentions that 'Ribbon Mics"
record better than
condensors because the transient part of the waveform is lower in the
ribbon microphone-therefore the sound of what is recorded sounds
louder. Micheal Jackson's
"Don't Stop" the percussion. Why would he state this. To record
transient music with
ribbons instead of condensors so the resonance of the waveform is
louder in
comparison to its transient?



> I think you are talking nonsense. The speed of response to a transient
> is determined by the high frequency response limit. This is just as
> good in a ribbon (if not better) as any other type of microphone. And
> a ribbon is quite likely to be rather less resonant than any other
> microphone as it is mass-controlled throughout the audio band - there
> is no resonant peak at the upper mid range.
>
> As for signals being too fast for a microphone to see them, how could
> that be? All the speed that matters in a signal is found within the
> audible band. A microphone that responds to that band has sufficient
> speed by definition.
>
> Now - what are you talking about?
>
> d
>
> --
> Pearce Consulting
> http://www.pearce.uk.com

[Mike Rivers]

wrote:
> I read an article By Bruce Swedien who mentions that 'Ribbon Mics"
> record better than
> condensors because the transient part of the waveform is lower in the
> ribbon microphone-therefore the sound of what is recorded sounds
> louder.

Hey, he's a recording engineer, not a physicist.

[Scott Dorsey]

> wrote:
>I have often wondered why Ribbon mics sound good on Brass and
>persussion because they are not fast enough to react to the transients
>and therefore get more of a resonant signal compared to the transient.

Not more of a "resonant" signal. But if you look at a brass instrument,
you'll see enormous spikes way above the average of the waveform. The ribbon
has trouble following that, and so much of the "blattiness" is smoothed out.

What is ironic is that the reason ribbon mikes originally became popular
is that they had the fastest response time and the widest bandwidth available
at the time. The reason they have become popular today is the exact opposite.

>Kinda like a compressor set with a slow attack time: the signal is too
>fast for the gear to see it?

Think of it more like slew limiting than actual dynamic compression.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Scott Dorsey]

Willie K. Yee, MD > wrote:
>
>Until the recent Chinese and Russian imports, how many "bad" ribbon
>mics are there? My thinking is that ribbons were difficult enough to
>make at all, that all that were made were of pretty good quality, with
>the exception of an occassional dud, which can happen with anything.
>
>Bad ribbons? Names, please.

Shure 315. Nice ribbon motor, competent grille design. Output transformer
from a transistor radio wired in reverse as a step-up. Absolutely unusable
it's so noisy.

Coles 4038. I know a lot of people love it, but the mike has no top end
whatsoever. I have real trouble with that.

RCA 74B. Surprisingly, the 74B has better pattern control (and therefore
has better gain before feedback in a PA application) than the 77 or 44
mikes. But the output level is very low and the output transformers are
very poor. Unlike the Shure, though, there is actually room inside to
retrofit a decent transformer.

I _might_ put the Altec 639 in that category... it's actually not all that
bad if you set it to pure ribbon mode.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Scott Dorsey]

> wrote:
>I read an article By Bruce Swedien who mentions that 'Ribbon Mics"
>record better than
>condensors because the transient part of the waveform is lower in the
>ribbon microphone-therefore the sound of what is recorded sounds
>louder. Micheal Jackson's
>"Don't Stop" the percussion. Why would he state this. To record
>transient music with
>ribbons instead of condensors so the resonance of the waveform is
>louder in
>comparison to its transient?

To some extent this is true, in that ribbons will tend to have some slew
limiting.

BUT, you should be VERY wary of things you read in these interviews, in part
because they are usually conducted by interviewers who have no idea what
the interviewee is talking about, and often the person being interviewed is
trying to deliberately obscure techniques he might consider proprietary.

Bruce Swedien once was interviewed talking about how he uses omnis in X-Y
to record choirs, to get a collapsed stereo image that integrates well
with panpotted stereo. But either he didn't explain WHY he did this, or
the interviewer didn't understand it. For the next year or two, people
kept asking me why I wasn't using X-Y omnis on choir jobs.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[[email protected]]

Thanks Scott
Makes sense to me now
kevin


> Think of it more like slew limiting than actual dynamic compression.
> --scott
> --
> "C'est un Nagra. C'est suisse, et tres, tres precis."

[Don Pearce]

On 26 Aug 2006 23:42:23 -0400, (Scott Dorsey) wrote:

> > wrote:
>>I have often wondered why Ribbon mics sound good on Brass and
>>persussion because they are not fast enough to react to the transients
>>and therefore get more of a resonant signal compared to the transient.
>
>Not more of a "resonant" signal. But if you look at a brass instrument,
>you'll see enormous spikes way above the average of the waveform. The ribbon
>has trouble following that, and so much of the "blattiness" is smoothed out.
>

A ribbon has no trouble following anything. Is this some sort of urban
myth you are writing here? If it is in the audible range, it will
follow it just as well as any other microphone.

>What is ironic is that the reason ribbon mikes originally became popular
>is that they had the fastest response time and the widest bandwidth available
>at the time. The reason they have become popular today is the exact opposite.
>
I have a ribbon with an individually measured curve that is flat to
20kHz, so I really don't understand what you mean by this. Flat to
20kHz means it has a step response time of better than about 12
microseconds. How quick do you need, and what kind of mic do you think
does better? A dynamic mic is a bit like a ribbon, but with a whole
heap of additional moving mass - do you suppose that could move
quicker?

>>Kinda like a compressor set with a slow attack time: the signal is too
>>fast for the gear to see it?
>
>Think of it more like slew limiting than actual dynamic compression.

Nothing even remotely like slew rate limiting goes on in a ribbon mic.
This is just nonsense.

d


--
Pearce Consulting
http://www.pearce.uk.com

[Don Pearce]

On 26 Aug 2006 21:02:08 -0700, wrote:

>Thanks Scott
>Makes sense to me now
>kevin
>
Kevin, think again. Not a word of what Scott wrote made the slightest
sense. It was gibberish.

d
--
Pearce Consulting
http://www.pearce.uk.com

[Predrag Trpkov]

"Don Pearce" > wrote in message
...

The speed of response to a transient
> is determined by the high frequency response limit. This is just as
> good in a ribbon (if not better) as any other type of microphone.


I was under impression that the high frequency response, along with low
sensitivity, is generally considered the main practical limitation of ribbon
microphones. "Dark" springs to mind first when describing the sound of
ribbons. Certainly none of the ribbons I've tried/heard had what could be
described as extended or detailed high end.

Not that it couldn't be used to advantage in artistic terms, but ribbon
microphones don't seem to be the weapon of choice whenever capturing a lot
of high frequencies is the primary concern.

Predrag

[Don Pearce]

On Sun, 27 Aug 2006 10:44:28 +0200, "Predrag Trpkov"
> wrote:

>
>"Don Pearce" > wrote in message
...
>
>The speed of response to a transient
>> is determined by the high frequency response limit. This is just as
>> good in a ribbon (if not better) as any other type of microphone.
>
>
>I was under impression that the high frequency response, along with low
>sensitivity, is generally considered the main practical limitation of ribbon
>microphones. "Dark" springs to mind first when describing the sound of
>ribbons. Certainly none of the ribbons I've tried/heard had what could be
>described as extended or detailed high end.
>
>Not that it couldn't be used to advantage in artistic terms, but ribbon
>microphones don't seem to be the weapon of choice whenever capturing a lot
>of high frequencies is the primary concern.
>
>Predrag
>
>

Certainly the ribbon I use has a very extended top end - it is
absolutely flat to 20kHz. What it also has, which might account for
the darker tone, is a complete absence of any presence hump, which
tends to brighten the sound of other types. Poor sensitivity is indeed
an issue, of course, but if you are recording a reasonably loud
instrument, that ceases to be a problem.

If you are after accurate capture of high frequencies, rather than
exaggerated capture, this mic would definitely be the instrument of
choice.

d

--
Pearce Consulting
http://www.pearce.uk.com

[Don Pearce]

On 26 Aug 2006 19:04:47 -0700, wrote:

>I read an article By Bruce Swedien who mentions that 'Ribbon Mics"
>record better than
>condensors because the transient part of the waveform is lower in the
>ribbon microphone-therefore the sound of what is recorded sounds
>louder. Micheal Jackson's
>"Don't Stop" the percussion. Why would he state this. To record
>transient music with
>ribbons instead of condensors so the resonance of the waveform is
>louder in
>comparison to its transient?
>
OK - that would certainly be true for my mic. The ratio of transient
to tone coming from a microphone depends on its frequency response.
Most microphones that use stretched diaphragms have a resonance at
several kHz. This can show itself as a broad hump, or a series of
peaks lying well above the average line of response. These resonances
will be excited by the transient part of the wave and result in higher
output of the transient than you should get. My ribbon has no such
rise, its primary resonance being down somewhere around a few Hz. This
makes the response much smoother, and you get none of that resonant
peaking that tends to exaggerate transients.

d

--
Pearce Consulting
http://www.pearce.uk.com

[Scott Dorsey]

Don Pearce > wrote:
>I have a ribbon with an individually measured curve that is flat to
>20kHz, so I really don't understand what you mean by this. Flat to
>20kHz means it has a step response time of better than about 12
>microseconds. How quick do you need, and what kind of mic do you think
>does better? A dynamic mic is a bit like a ribbon, but with a whole
>heap of additional moving mass - do you suppose that could move
>quicker?

Where did you find a ribbon flat to 20KC?

And no, I don't think a dynamic would do any better (although occasionally
some do).

>>>Kinda like a compressor set with a slow attack time: the signal is too
>>>fast for the gear to see it?
>>
>>Think of it more like slew limiting than actual dynamic compression.
>
>Nothing even remotely like slew rate limiting goes on in a ribbon mic.
>This is just nonsense.

Again, I'd like to see where you found a ribbon that is "flat to 20 KC."
You'll be hard-pressed to find one that isn't a total mess in the top
octave, if only due to grille issues.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Don Pearce]

On 27 Aug 2006 07:57:20 -0400, (Scott Dorsey) wrote:

>Don Pearce > wrote:
>>I have a ribbon with an individually measured curve that is flat to
>>20kHz, so I really don't understand what you mean by this. Flat to
>>20kHz means it has a step response time of better than about 12
>>microseconds. How quick do you need, and what kind of mic do you think
>>does better? A dynamic mic is a bit like a ribbon, but with a whole
>>heap of additional moving mass - do you suppose that could move
>>quicker?
>
>Where did you find a ribbon flat to 20KC?
>
>And no, I don't think a dynamic would do any better (although occasionally
>some do).
>
>>>>Kinda like a compressor set with a slow attack time: the signal is too
>>>>fast for the gear to see it?
>>>
>>>Think of it more like slew limiting than actual dynamic compression.
>>
>>Nothing even remotely like slew rate limiting goes on in a ribbon mic.
>>This is just nonsense.
>
>Again, I'd like to see where you found a ribbon that is "flat to 20 KC."
>You'll be hard-pressed to find one that isn't a total mess in the top
>octave, if only due to grille issues.
>--scott

I've posted this before, but have a look and a listen. This ribbon is
one I bought in 1967, and it has an unbelievably smooth sound.

http:81.174.169.10

d

--
Pearce Consulting
http://www.pearce.uk.com

[Laurence Payne]

On Sun, 27 Aug 2006 12:00:04 GMT, (Don Pearce)
wrote:

>I've posted this before, but have a look and a listen. This ribbon is
>one I bought in 1967, and it has an unbelievably smooth sound.
>
>http:81.174.169.10

Want to check that link?

[Don Pearce]

On Sun, 27 Aug 2006 13:14:47 +0100, Laurence Payne
<lpayne1NOSPAM@dslDOTpipexDOTcom> wrote:

>On Sun, 27 Aug 2006 12:00:04 GMT, (Don Pearce)
>wrote:
>
>>I've posted this before, but have a look and a listen. This ribbon is
>>one I bought in 1967, and it has an unbelievably smooth sound.
>>
>>http:81.174.169.10
>
>Want to check that link?

http://81.174.169.10

Sorry, lost my ISP for a few minutes. Try again - typos corrected
(this one is on a PC here at home)

d

--
Pearce Consulting
http://www.pearce.uk.com

[John Phillips]

"Don Pearce" > wrote in message
...
> ...Certainly the ribbon I use has a very extended top end - it is
> absolutely flat to 20kHz....
> Pearce Consulting
> http://www.pearce.uk.com

What ribbon mic do you use?

John Phillips

[Ian Bell]

Don Pearce wrote:

> On 27 Aug 2006 07:57:20 -0400, (Scott Dorsey) wrote:
>
>>
>>Again, I'd like to see where you found a ribbon that is "flat to 20 KC."
>>You'll be hard-pressed to find one that isn't a total mess in the top
>>octave, if only due to grille issues.
>>--scott
>
> I've posted this before, but have a look and a listen. This ribbon is
> one I bought in 1967, and it has an unbelievably smooth sound.
>
> http:81.174.169.10
>

So it's a Grampian GR2. I don't ever remember them being flat to 20KHz. I
don't know where graph from on the web site you mentioned comes from but I
doubt it is for a GR2. I remember it being reviewed in Tape Recorder
magazine in the UK along with a bunch of others around 1963. ISTR the
reviewer fixed all the review models onto a horizontal piece of wood and
recorded from them simultaneously.

Anyway if memory serves the GR2 is only specced to 15KHz It is a very nice
mic, very smooth and open. I know because I bought two after that review
and I still have and use one of them.

Ian

[Don Pearce]

On Sun, 27 Aug 2006 12:41:51 GMT, "John Phillips"
> wrote:

>"Don Pearce" > wrote in message
...
>> ...Certainly the ribbon I use has a very extended top end - it is
>> absolutely flat to 20kHz....
>> Pearce Consulting
>> http://www.pearce.uk.com
>
>What ribbon mic do you use?
>
Very obsolete - Grampian GR2. There is a link to some details further
down the thread.

d

--
Pearce Consulting
http://www.pearce.uk.com

[John Phillips]

"Scott Dorsey" > wrote in message
...
> Willie K. Yee, MD > wrote:
....
>>
>>Bad ribbons? Names, please.
>
> Shure 315. ...
> --scott
>
> --
> "C'est un Nagra. C'est suisse, et tres, tres precis."

Good ribbons?

I would like to know the groups favorites for vocals and guitars.

John Phillips

[Don Pearce]

On Sun, 27 Aug 2006 13:45:49 +0100, Ian Bell >
wrote:

>Don Pearce wrote:
>
>> On 27 Aug 2006 07:57:20 -0400, (Scott Dorsey) wrote:
>>
>>>
>>>Again, I'd like to see where you found a ribbon that is "flat to 20 KC."
>>>You'll be hard-pressed to find one that isn't a total mess in the top
>>>octave, if only due to grille issues.
>>>--scott
>>
>> I've posted this before, but have a look and a listen. This ribbon is
>> one I bought in 1967, and it has an unbelievably smooth sound.
>>
>> http:81.174.169.10
>>
>
>So it's a Grampian GR2. I don't ever remember them being flat to 20KHz. I
>don't know where graph from on the web site you mentioned comes from but I
>doubt it is for a GR2. I remember it being reviewed in Tape Recorder
>magazine in the UK along with a bunch of others around 1963. ISTR the
>reviewer fixed all the review models onto a horizontal piece of wood and
>recorded from them simultaneously.
>
>Anyway if memory serves the GR2 is only specced to 15KHz It is a very nice
>mic, very smooth and open. I know because I bought two after that review
>and I still have and use one of them.
>
>Ian

That graph is the individual measurement that has lived in the box
with that mic ever since I bought it. They spec flat to 15, and
measure flat to 20.

d

--
Pearce Consulting
http://www.pearce.uk.com

[HKC]

John Phillips wrote: I would like to know the groups favorites for vocals
and guitars.

I´m not crazy about ribbons on vocals as such. Ribbons are great when you
have something with a midrangy edge. They have an ability to smoothen out
sounds and bring up the low end (when hit heavily, like the air from guitar
amps, brass, overheads etc). Unless you´re dealing with vocalists in this
category I would go for a nice (or even semi nice) tube mic instead.
I have had the opportunity to try out many of the modern more expensive
ribbons like the Royers and Crowley and Tripp but in the end I decided to
buy the Oktava ML52 because they sound fine on guitar amps and overheads
(which is mainly what I need) and very importently they are cheap (ish). I
am not saying that this is the greatest ribbon by any means but it´s not the
worst either and it does do what ribbons are mostly used for.
This is the second time in a short while that ribbons have been discussed
here and like the first time I think it´s important to underline that
ribbons need a lot of gain (except a few newer ones like the Royer R122) so
a good preamp is an absolute must.
Another point is that most ribbons are very fragile and can easily break
(very easily, it´s not just if you mess up) by too much pressure which cost
a 100 dollars or more everytime. This is a bit unlucky because they really
sound best when pressured. You can achieve similar sounds with broadcast
mics like the Shure SM7B or Electrovoice RE20, not exactly but without the
problems with handling the pressure.
Anyway I´m not saying "don´t buy a ribbon" because I have two myself but I
do think the current fuzz around ribbons are based on people thinking that
ribbons will neccesarily bring out vintage sounds. This is not so, in many
cases all they will give you is a dull, lifeless sound and they are not very
versatile either. On the other hand, in other (few) cases they simply sound
better than anything else so if you have the standard mic selections covered
it´s time to get a ribbon.

[Scott Dorsey]

John Phillips > wrote:
>
>Good ribbons?
>
>I would like to know the groups favorites for vocals and guitars.

The usual 77s and 44s still get a lot of use around here, and the 74b is
actually not bad if it's got a decent transformer in it.

The AEA reissue is just like the original 44 too.

I still use the BK-5s as choir fills occasionally when I have to spot
choirs, or for backing vocals.

I think the Shure SM-33 is somewhat underrated but actually a very useful
mike to have in the kit.

I remain absolutely stunned by the Coles 4040, which actually has the most
solid top end I have heard on a ribbon mike.

And the Beyer M160, M260, and M130 are very handy as well, and not all
that expensive. The M500 is useful on some kinds of vocals too.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[[email protected]]

Scott Dorsey wrote:
> Don Pearce > wrote:
> >I have a ribbon with an individually measured curve that is flat to
> >20kHz, so I really don't understand what you mean by this. Flat to
> >20kHz means it has a step response time of better than about 12
> >microseconds. How quick do you need, and what kind of mic do you think
> >does better? A dynamic mic is a bit like a ribbon, but with a whole
> >heap of additional moving mass - do you suppose that could move
> >quicker?
>
> Where did you find a ribbon flat to 20KC?
>
> And no, I don't think a dynamic would do any better (although occasionally
> some do).
>
> >>>Kinda like a compressor set with a slow attack time: the signal is too
> >>>fast for the gear to see it?
> >>
> >>Think of it more like slew limiting than actual dynamic compression.
> >
> >Nothing even remotely like slew rate limiting goes on in a ribbon mic.
> >This is just nonsense.
>
> Again, I'd like to see where you found a ribbon that is "flat to 20 KC."
> You'll be hard-pressed to find one that isn't a total mess in the top
> octave, if only due to grille issues.
> --scott
> --
> "C'est un Nagra. C'est suisse, et tres, tres precis."

Hey,

I'm on the road today and checking in through Google Groups. I've yet
to hear a ribbon with much of anything above 12 kHz (and that's pushing
it).

Why use them on brass was the question, right? They smooth the top end
because they don't have a top end. The same for some hard smacky
percussion things; rack of chimes and trangle.

I DO like the explanation of not having the upper problematic
resonances that ccondenser mocs have.

Regards,

Ty Ford

[zero]

"Don Pearce" > wrote in message
...
> On Sun, 27 Aug 2006 13:45:49 +0100, Ian Bell >
> wrote:

<snip>
> That graph is the individual measurement that has lived in the box
> with that mic ever since I bought it.
<snip>

Well,,, that about says it all.

You feel much better about yourself when you reply to a post, don't you?


-zero

[Don Pearce]

On Sun, 27 Aug 2006 16:41:55 GMT, "zero"
> wrote:

>
>"Don Pearce" > wrote in message
...
>> On Sun, 27 Aug 2006 13:45:49 +0100, Ian Bell >
>> wrote:
>
><snip>
>> That graph is the individual measurement that has lived in the box
>> with that mic ever since I bought it.
><snip>
>
>Well,,, that about says it all.
>
>You feel much better about yourself when you reply to a post, don't you?
>
No idea what you are talking about. Are you sure you have replied to
the right post?

d

--
Pearce Consulting
http://www.pearce.uk.com

[Paul Stamler]

"Scott Dorsey" > wrote in message
...
> > wrote:

> >Kinda like a compressor set with a slow attack time: the signal is too
> >fast for the gear to see it?
>
> Think of it more like slew limiting than actual dynamic compression.

Not really slew limiting; that's a term with a very specific meaning, one
relating to electronic circuits rather than mechanical devices. (It happens
when an active stage is trying to charge up a capacitor but doesn't have
enough current available to do so quickly enough to follow the signal.)

What's going on with a ribbon microphone is simply the result of its
frequency response; typically this begins rolling off at around 12kHz,
although a few mics go out to 20kHz before rolling off. A low-pass filter
will reduce the amplitude of transients which contain frequency components
outside of its bandpass.

The other thing that's going on is what *isn't* going on. Many condenser
(and some dynamic) mics have upper-frequency peaks that exaggerate
transients. Most ribbon mics don't.

Peace,
Paul

[Ian Bell]

Don Pearce wrote:

> On Sun, 27 Aug 2006 13:45:49 +0100, Ian Bell >

>>
>>Anyway if memory serves the GR2 is only specced to 15KHz It is a very nice
>>mic, very smooth and open. I know because I bought two after that review
>>and I still have and use one of them.
>>
>>Ian
>
> That graph is the individual measurement that has lived in the box
> with that mic ever since I bought it. They spec flat to 15, and
> measure flat to 20.
>
> d
>

Interesting. Neither of my (low impedance) GR2 ribbons came with any such
graph and I cannot believe if they routinely achieve 20KHz they would not
spec it AND up the price. Also I would be suspicious of a HI-Z mic
achieving this because of the transformer losses particularly in the
secondary. Nevertheless it is a very good mic and I would not be without
mine. I would love to believe its response extends to 20K. Might just have
to go and test that.

Ian

[[email protected]]

A question for Dan

The questions I am being faced with by a producer is that he states;
That due to the physical mass of the Ribbon it can not respond quickly
enough to transients. Any answers on this Dan
kevin

[Don Pearce]

On 27 Aug 2006 10:49:42 -0700, wrote:

>A question for Dan
>
>The questions I am being faced with by a producer is that he states;
>That due to the physical mass of the Ribbon it can not respond quickly
>enough to transients. Any answers on this Dan
>kevin

I'm Don, not Dan but I assume you are talking to me.

He is simply wrong. The ribbon is unbelievably light - much lighter
than the diaphragm of a condensor mic. And since the entire audible
range is mass-controlled, the actual mass affects only the output
level, not the upper frequency. It is geometry and moding that limit
this.

d

--
Pearce Consulting
http://www.pearce.uk.com

[Chris Hornbeck]

On Sun, 27 Aug 2006 17:28:06 GMT, "Paul Stamler"
> wrote:

>What's going on with a ribbon microphone is simply the result of its
>frequency response; typically this begins rolling off at around 12kHz,
>although a few mics go out to 20kHz before rolling off. A low-pass filter
>will reduce the amplitude of transients which contain frequency components
>outside of its bandpass.

One way of thinking about it is that ribbon mic's have
fundamental (mass x compliance) resonances below, or
almost below, the audio range. Their pressure gradient
response is flat as far up in frequency as the ribbon
can keep up with the pressure gradient.

Above some frequency the ribbon is too heavy to keep up,
and gives a single pole "mass" rolloff. Getting this to
be above the audio range in a ribbon with usable output
must be very challenging.

Condensor mic's try to put their fundamental resonances
*above* the audio range, or at least in some commercially
useful "presence" range. Their pressure response is flat
*below* fundamental resonance.


Much thanks, as always,

Chris Hornbeck
"History consists of truths which in the end turn into lies,
while myth consists of lies which finally turn into truths."
- Jean Cocteau

[[email protected]]

> I remain absolutely stunned by the Coles 4040, which actually has the most
> solid top end I have heard on a ribbon mike.


Isn't that what you normally look for in a ribbon, though: having
the top end rolled off?
What are the beneficial "ribbon characteristics" that the 4040 retains?

[Scott Dorsey]

> wrote:
>> I remain absolutely stunned by the Coles 4040, which actually has the most
>> solid top end I have heard on a ribbon mike.
>
>Isn't that what you normally look for in a ribbon, though: having
>the top end rolled off?

No, that's a disadvantage in most cases to my mind.

>What are the beneficial "ribbon characteristics" that the 4040 retains?

It sounds good. It sounds like what's in front of it. That's the way mikes
ought to be, to my mind. Try one.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Geoff]

wrote:
> I have often wondered why Ribbon mics sound good on Brass and
> persussion because they are not fast enough to react to the transients
> and therefore get more of a resonant signal compared to the transient.
> Kinda like a compressor set with a slow attack time: the signal is too
> fast for the gear to see it?
> Any thoughts?
> kevin
>
> www.kevindoylemusic.com

No. Kind of like a mic with a sock over it, or treble attenuation EQ.

geoff

[Roy W. Rising]

(Scott Dorsey) wrote:
> > wrote:
> >> I remain absolutely stunned by the Coles 4040, which actually has the
> >> most solid top end I have heard on a ribbon mike.
> >
> >Isn't that what you normally look for in a ribbon, though: having
> >the top end rolled off?
>
> No, that's a disadvantage in most cases to my mind.
>
> >What are the beneficial "ribbon characteristics" that the 4040 retains?
>
> It sounds good. It sounds like what's in front of it. That's the way
> mikes ought to be, to my mind. Try one.
> --scott

Reading everyone's opinions of ribbons is fascinating. Perhaps it should
be mentioned that a ribbon mic is a form of dynamic where the ribbon may be
thought of as a half-turn winding in a magnetic field. Even the best begin
to roll off around 12KHz.

It is the nature of many condensors to be somewhat peaky in the high end
.... some manufactures manage this peakiness by placing it in the "presence"
range and showing the peaks averaged out in their graphs. Large diaphragm
condensors introduce their own family of problems ... acoustical phase
distortion from varying arrival times across the diaphragm, summations and
cancellations due to reflection of dead on axis sources.

If you want smooth, flat response to 18KHz, try an EV RE55 (or DO54/PL9 if
you don't need extreme low end). Make a double track recording against any
other mic and listen to the clarity of the RE55.

--
~ Roy
"If you notice the sound, it's wrong!"

[Bob Cain]

Scott Dorsey wrote:
> > wrote:
>> I read an article By Bruce Swedien who mentions that 'Ribbon Mics"
>> record better than
>> condensors because the transient part of the waveform is lower in the
>> ribbon microphone-therefore the sound of what is recorded sounds
>> louder. Micheal Jackson's
>> "Don't Stop" the percussion. Why would he state this. To record
>> transient music with
>> ribbons instead of condensors so the resonance of the waveform is
>> louder in
>> comparison to its transient?
>
> To some extent this is true, in that ribbons will tend to have some slew
> limiting.

Huh? What causes slew rate limiting in a ribbon? Or are you talking
about something different than the common definition as it applies to
amplifiers?

From the last thread here on ribbons I came away believing that they
simply don't have the HF response, about half the bandwidth, of a
condenser so that the fast part of a transient would in fact be
suppressed.


Bob
--

"Things should be described as simply as possible, but no simpler."

A. Einstein

[Bob Cain]

Don Pearce wrote:
> On 26 Aug 2006 21:02:08 -0700, wrote:
>
>> Thanks Scott
>> Makes sense to me now
>> kevin
>>
> Kevin, think again. Not a word of what Scott wrote made the slightest
> sense. It was gibberish.

Only the part about slew rate limiting. That's far different from HF
rolloff and there is no mechanism in a ribbon to account for any slew
rate limiting. Passive devices just don't have that characteristic.


Bob
--

"Things should be described as simply as possible, but no simpler."

A. Einstein

[Scott Dorsey]

Roy W. Rising > wrote:
>If you want smooth, flat response to 18KHz, try an EV RE55 (or DO54/PL9 if
>you don't need extreme low end). Make a double track recording against any
>other mic and listen to the clarity of the RE55.

The RE-55 is a very fine mike. But you really SHOULD give a listen both to
the Coles 4040, and the Crowley-Tripp Vocalist if you want a very different
(and much more extended) ribbon experience.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Chris Hornbeck]

On Sun, 27 Aug 2006 16:07:55 -0700, Bob Cain
> wrote:

>Only the part about slew rate limiting. That's far different from HF
>rolloff and there is no mechanism in a ribbon to account for any slew
>rate limiting. Passive devices just don't have that characteristic.

There is a high frequency where diaphragm motion can
no longer keep up with instantaneous differential pressure.
It's not usually thought of as being level-sensitive,
so maybe slewing isn't the best analogy.

Probably better to call it a "mass rolloff", because that's
been in use in the loudspeaker world for a while, and also
applies completely.

Much thanks, as always,

Chris Hornbeck
"History consists of truths which in the end turn into lies,
while myth consists of lies which finally turn into truths."
- Jean Cocteau

[Chris Hornbeck]

On Sun, 27 Aug 2006 17:58:22 GMT, (Don Pearce)
wrote:

>On 27 Aug 2006 10:49:42 -0700, wrote:
>>The questions I am being faced with by a producer is that he states;
>>That due to the physical mass of the Ribbon it can not respond quickly
>>enough to transients. Any answers on this Dan

>He is simply wrong. The ribbon is unbelievably light - much lighter
>than the diaphragm of a condensor mic. And since the entire audible
>range is mass-controlled, the actual mass affects only the output
>level, not the upper frequency. It is geometry and moding that limit
>this.

And even the term "mass-controlled" can be easily misinterpreted
as an analogy. Some will understand it from its exotic origins
and others (including, I'd guess, the OP) will consider it to be
taken more literally than intended. Much like "slew-limited".
Good analogy; not to be taken literally.

Output voltage is related linearly to diaphragm displacement in
condenser mics and to diaphragm velocity in dynamic mics. Note
that neither of these is *pressure*, absolute, differential or
chicken-fried. What we'd like for a microphone is a *pressure*-
to-voltage converter, and ideally one that's frequency-invariant
in its passband.

Two models give frequency-invariant pressure-voltage response:
pressure-sensitive diaphragm motion in condenser mics with their
mass/compliance resonance above their working range, and pressure
-gradient-sensitive diaphragm motion in dynamic mics with their
fundamental resonance below their working range.

And, for completeness, in the passband, diaphragm excursion is not
related directly to frequency in any way, or to any characteristics
of the electrical generating mechanism. In both cases, the diaphragm
must accurately follow instantaneous pressure differentials across
itself. Diaphragm excursion in the passband is not related to
frequency per se, or to generator characteristics, but only to
differential pressure.

But above some high frequency, the diaphragm's accurate tracing of
instantaneous differential pressure fails, and "mass rolloff" occurs,
at 6dB per octave.

Above this high frequency, an analogy to slew limiting occurs, or
the diaphragm could, in popular parlance, be said to be mass-
controlled. Neither is completely accurate; both terms have other
very specific meanings; but both are useful analogies.

Much thanks, as always,

Chris Hornbeck
"History consists of truths which in the end turn into lies,
while myth consists of lies which finally turn into truths."
- Jean Cocteau

[Scott Dorsey]

Chris Hornbeck > wrote:
>On Sun, 27 Aug 2006 16:07:55 -0700, Bob Cain
> wrote:
>
>>Only the part about slew rate limiting. That's far different from HF
>>rolloff and there is no mechanism in a ribbon to account for any slew
>>rate limiting. Passive devices just don't have that characteristic.
>
>There is a high frequency where diaphragm motion can
>no longer keep up with instantaneous differential pressure.
>It's not usually thought of as being level-sensitive,
>so maybe slewing isn't the best analogy.

In the case of the ribbon, there are air compression issues which ARE
level-sensitive, on top of the primary resonance that is the result
of the ribbon tension and mass. Some of these effects also exist in
very small condenser designs as well, as Juha Backman showed a few years
ago.
--scott


--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Scott Fraser]

>>Only the part about slew rate limiting. ...snip...>There is a high frequency where diaphragm motion can no longer keep up with instantaneous differential pressure. It's not usually thought of as being level-sensitive, so maybe slewing isn't the best analogy. >>

Isn't what's being referred to here really mechanical inertia?

Scott Fraser

[[email protected]]

> But you really SHOULD give a listen both to
> the Coles 4040, and the Crowley-Tripp Vocalist if you want a very different
> (and much more extended) ribbon experience.

How's the top end in these? Extremely smooth?

[Scott Dorsey]

> wrote:
>> But you really SHOULD give a listen both to
>> the Coles 4040, and the Crowley-Tripp Vocalist if you want a very different
>> (and much more extended) ribbon experience.
>
>How's the top end in these? Extremely smooth?

It's very extended. Smooth? I dunno. Is a Schoeps smooth to you?
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Bob Cain]

Scott Fraser wrote:
>>> Only the part about slew rate limiting. ...snip...>There is a high frequency where diaphragm motion can no longer keep up with instantaneous differential pressure. It's not usually thought of as being level-sensitive, so maybe slewing isn't the best analogy. >>
>
> Isn't what's being referred to here really mechanical inertia?

Yes. Modeled as an inductance in an equivalent circuit representation.

Here's the skinny. The EMF (signal) out of the mic is

EMF ~= v.

That is, the EMF is proportional to the velocity of the ribbon.

And

v ~= F/f.

That is, the velocity of the ribbon is proportional to the force on
the ribbon divided by the frequency _IF_ the ribbon is mass controlled
over its audible range which it is in a ribbon. This is a consequence
of Newton's observation that F=MA.

The ribbon is a pressure differential device so that the force on the
ribbon is proportional to the difference between the pressure at the
front and the pressure at the back. In a constant pressure sound
field, that difference is a function of frequency

F ~= dP/dx ~= P*f

because at low frequencies the wavelength is long and the difference
in pressure at two closely spaced points is small. As the frequency
rises and the wavelength gets shorter, the pressure difference gets
bigger.

Thus we get that

v ~= P*f/f ~= P

and

EMV ~= P

Just as we would like for a flat frequency response to pressure. Thus
the ribbon response to pressure is inherently flat over the band in
which it is mass controled and that certainly includes the higher
frequencies. The effect of higher ribbon mass is just to reduce the
sensitivity of the mic.

So where does the HF rolloff that we see in ribbons come from? In
large part it is because the front to back distance gets close to the
sound's wavelength within the audible band. At the frequency
corresponding to that wavelength the front and back pressures are
exactly in phase and the net pressure/force on the ribbon is zero. So
as we approach the frequency where the front to back distance becomes
appreciable compared to the wavelength of the sound, the output begins
to roll off, becoming zero when the wavelength equals the front to
back distance.

The above is also true of the dynamic mic of which the ribbon is just
a particular physical configuration.


Bob
--

"Things should be described as simply as possible, but no simpler."

A. Einstein

[Chris Hornbeck]

On 28 Aug 2006 10:38:00 -0400, (Scott Dorsey) wrote:

>In the case of the ribbon, there are air compression issues which ARE
>level-sensitive, on top of the primary resonance that is the result
>of the ribbon tension and mass. Some of these effects also exist in
>very small condenser designs as well, as Juha Backman showed a few years
>ago.

Very interesting, indeed. Looking forward to catching up.

Much thanks, as always,

Chris Hornbeck
"History consists of truths which in the end turn into lies,
while myth consists of lies which finally turn into truths."
- Jean Cocteau

[Chris Hornbeck]

On Mon, 28 Aug 2006 14:58:41 -0700, Bob Cain
> wrote:

<mostly snipped, 'cause ya already read and saved it>

Beautiful; thanks as always.

I do have two (closely related) unresolved issues though. The first is
that this ideal model is based on a diaphragm that appears massless
forever. It assumes that the diaphragm can always respond to the
instantaneous pressure differential across itself.

The assumption is good for most of its passband, but not forever.

>Just as we would like for a flat frequency response to pressure. Thus
>the ribbon response to pressure is inherently flat over the band in
>which it is mass controled and that certainly includes the higher
>frequencies. The effect of higher ribbon mass is just to reduce the
>sensitivity of the mic.

The second is the possibility of misunderstanding from the use
of the words "mass controlled". Its plainest meaning is that
we're operating above fundamental resonance, but many other
meanings are often implied.

When this came up last summer, some posters had conflated the
term to mean that the diaphragm somehow "lagged behind" instantaneous
pressure differential in the passband.


Anywho, a freely suspended diaphragm in moving air has its own
upper limit of response to differential pressure because of its
mass. Otherwise, the models predict some ringing around the
geometrical region, then response (plus 6dB) forever.

Much thanks, as always,

Chris Hornbeck
"History consists of truths which in the end turn into lies,
while myth consists of lies which finally turn into truths."
- Jean Cocteau

[Bob Cain]

Chris Hornbeck wrote:
> On Mon, 28 Aug 2006 14:58:41 -0700, Bob Cain
> > wrote:
>
> <mostly snipped, 'cause ya already read and saved it>
>
> Beautiful; thanks as always.

<blush>

> I do have two (closely related) unresolved issues though. The first is
> that this ideal model is based on a diaphragm that appears massless
> forever. It assumes that the diaphragm can always respond to the
> instantaneous pressure differential across itself.

Not massless at all. It just acts as a multiplier in the relationship

v ~= F/f.

More specifically

v = F/(M*f).

for the velocity of the ribbon in response to the force on it. BTW,
these symbols for force, velocity, pressure, etc. all represent the
amplitudes of sinusoidal signals.

So mass just scales the velocity response to the force on the ribbon
by a constant which is why it only affects the sensitivity. I should
have been more explicit about why this is so in my other post.

> The assumption is good for most of its passband, but not forever.

It's good so long as it's the mass that is primarily controlling the
response of the ribbon. As you move toward forever, the v just gets
smaller and smaller in proportion to the reciprocal of the frequency.

Where this fails is when the pressure difference between front and
back begins failing as a measure of the pressure gradient at the
ribbon due to phase shift interference. Unfortunately this occurs in
the upper audio band because of the size of the objects used to
measure that front-back approximation to the gradient. This isn't
about the mass though.

As you go down toward never, the compliance of the ribbon becomes
significant and eventually dominates the mass so that these simple
relationships again fail to be good approximations.

>
>> Just as we would like for a flat frequency response to pressure. Thus
>> the ribbon response to pressure is inherently flat over the band in
>> which it is mass controlled and that certainly includes the higher
>> frequencies. The effect of higher ribbon mass is just to reduce the
>> sensitivity of the mic.
>
> The second is the possibility of misunderstanding from the use
> of the words "mass controlled". Its plainest meaning is that
> we're operating above fundamental resonance, but many other
> meanings are often implied.

I just mean that in the approximate equivalent circuit there is only a
mass involved in calculating velocity/pressure relationships and, yes,
that would be well above the resonance caused by the mass and
compliance of the ribbon.

> When this came up last summer, some posters had conflated the
> term to mean that the diaphragm somehow "lagged behind" instantaneous
> pressure differential in the passband.

It does, just as the (sinusoidal) velocity response of a mass lags the
stimulating force. It affects the phase relationship between them in
the same way that the current in an inductor lags the voltage across it.

It occurs to me that the amplitude compensating frequency dependance
of the pressure gradient does not have a lead that compensates the
mass lag. That would make the overall system an allpass with constant
amplitude and frequency dependent lagging phase shift. Don't hold me
to this, however, it's just off the top of my head.

> Anywho, a freely suspended diaphragm in moving air has its own
> upper limit of response to differential pressure because of its
> mass.

There is no knee if that is what you mean. The velocity response to a
constant amplitude force/pressure just keeps getting smaller and
smaller as you go up in frequency as per the above equation.

> Otherwise, the models predict some ringing around the
> geometrical region, then response (plus 6dB) forever.

Sorry, I don't follow you here.


Bob
--

"Things should be described as simply as possible, but no simpler."

A. Einstein

[[email protected]]

Scott Fraser wrote:
> Isn't what's being referred to here really mechanical inertia?
>
That's what I Thought
kevin

[Chris Hornbeck]

On Tue, 29 Aug 2006 13:50:49 -0700, Bob Cain
> wrote:

>There is no knee if that is what you mean. The velocity response to a
>constant amplitude force/pressure just keeps getting smaller and
>smaller as you go up in frequency as per the above equation.

>> Otherwise, the models predict some ringing around the
>> geometrical region, then response (plus 6dB) forever.
>
>Sorry, I don't follow you here.

Yeah, clear as mud, wasn't it? Trying again: as frequency
increases diaphragm size becomes significant. Through a
region where its geometry is similar in size to wavelength,
response rings with comb-filtering.

Above this region, the diaphragm is large compared to wavelength,
and response *rises*. The unexposed face is at constant pressure,
so velocity will rise with frequency.

So, this model predicts an unlimited frequency response with
a large flat region, then some ringing, then a rise forever.

What am I missing?

Much thanks, as always,

Chris Hornbeck
"History consists of truths which in the end turn into lies,
while myth consists of lies which finally turn into truths."
- Jean Cocteau

[Chris Hornbeck]

On Wed, 30 Aug 2006 00:31:20 GMT, Chris Hornbeck
> wrote:

>So, this model predicts an unlimited frequency response with
>a large flat region, then some ringing, then a rise forever.

Who writes this crap anyway? Obviously, response rings
through the geometric region, then rises asymptotically
to a "reference efficiency" level, above which it's
level and without comb-filtering effects.

I musta conflated near-field and far-field in my
pea brain. Sorry.

But it still doesn't predict any high frequency
limit. And I still believe that the observed high
frequency limit is one of mass decoupling from
differential pressure.

Well, sounds good....

Much thanks, as always,

Chris Hornbeck
"History consists of truths which in the end turn into lies,
while myth consists of lies which finally turn into truths."
- Jean Cocteau

[Bob Cain]

Chris Hornbeck wrote:
> On Wed, 30 Aug 2006 00:31:20 GMT, Chris Hornbeck
> > wrote:
>
>> So, this model predicts an unlimited frequency response with
>> a large flat region, then some ringing, then a rise forever.
>
> Who writes this crap anyway? Obviously, response rings
> through the geometric region, then rises asymptotically
> to a "reference efficiency" level, above which it's
> level and without comb-filtering effects.

If you say so. :-)

I don't have a clue as to how to predict what happens as the
wavelength gets small compared to the dimensions of the device. I
think it would take something like the finite element method, boundary
element method or other simulation to figure it out for any specific
geometry.

>
> I musta conflated near-field and far-field in my
> pea brain. Sorry.
>
> But it still doesn't predict any high frequency
> limit. And I still believe that the observed high
> frequency limit is one of mass decoupling from
> differential pressure.
>
> Well, sounds good....

:-)

I don't think the HF response is mechanically limited, just ****ed up.


Bob
--

"Things should be described as simply as possible, but no simpler."

A. Einstein

[Chris Hornbeck]

On Tue, 29 Aug 2006 22:41:50 -0700, Bob Cain
> wrote:

>I don't have a clue as to how to predict what happens as the
>wavelength gets small compared to the dimensions of the device. I
>think it would take something like the finite element method, boundary
>element method or other simulation to figure it out for any specific
>geometry.

If we assume the diaphragm to be "massless" we can easily
work backwards from the behavior of low mass loudspeaker
diaphragms, like electrostatic speakers, as dipole radiators
in free air. Let's also assume that fundamental resonance
is far away somewhere.

At high frequencies, the diaphragm radiates into a column of
its own shape; response anywhere on axis is just like nearfield.

At lower frequencies radiation widens until it approaches the
classic figure-of-eight. This is maintained indefinitely for
all lower frequencies.

In the region where geometry is comparable to wavelength,
magnitude response rings with comb filtering. Below this
region magnitude response falls at 20dB/decade. (In ribbon
microphones this region of falling response is the working
range.)

Because this behavior is a function only of size relative to
wavelength, I believe it to apply to a "massless" freely suspended
microphone diaphragm also, just seen from the other end of
the telescope.

Maybe a strong implication, but hardly proof, that a "mass
rolloff", as in loudspeaker compression drivers, is the
cause of ribbon mic high frequency final rolloff. Very
interested in your thoughts, as always.


Much thanks, as always,

Chris Hornbeck
"History consists of truths which in the end turn into lies,
while myth consists of lies which finally turn into truths."
- Jean Cocteau

[just wondering]

Chris Hornbeck > wrote in
:

> On Tue, 29 Aug 2006 22:41:50 -0700, Bob Cain
> > wrote:
>
>>I don't have a clue as to how to predict what happens as the
>>wavelength gets small compared to the dimensions of the device. I
>>think it would take something like the finite element method, boundary
>>element method or other simulation to figure it out for any specific
>>geometry.
>
> If we assume the diaphragm to be "massless" we can easily
> work backwards from the behavior of low mass loudspeaker
> diaphragms, like electrostatic speakers, as dipole radiators
> in free air. Let's also assume that fundamental resonance
> is far away somewhere.
>
> At high frequencies, the diaphragm radiates into a column of
> its own shape; response anywhere on axis is just like nearfield.
>
> At lower frequencies radiation widens until it approaches the
> classic figure-of-eight. This is maintained indefinitely for
> all lower frequencies.
>
> In the region where geometry is comparable to wavelength,
> magnitude response rings with comb filtering. Below this
> region magnitude response falls at 20dB/decade. (In ribbon
> microphones this region of falling response is the working
> range.)
>
> Because this behavior is a function only of size relative to
> wavelength, I believe it to apply to a "massless" freely suspended
> microphone diaphragm also, just seen from the other end of
> the telescope.
>
> Maybe a strong implication, but hardly proof, that a "mass
> rolloff", as in loudspeaker compression drivers, is the
> cause of ribbon mic high frequency final rolloff. Very
> interested in your thoughts, as always.
>
>
> Much thanks, as always,
>
> Chris Hornbeck
> "History consists of truths which in the end turn into lies,
> while myth consists of lies which finally turn into truths."
> - Jean Cocteau



Were you born with **** for brains or is it that you either didn't take any
physics/engineering courses in college or that you took them but didn't
learn anything from them? These are the only three possibilities that
would account for your gross technical ignorance.

[Chris Hornbeck]

On Sat, 02 Sep 2006 02:07:08 -0000, just wondering
> wrote:

>Were you born with **** for brains or is it that you either didn't take any
>physics/engineering courses in college or that you took them but didn't
>learn anything from them? These are the only three possibilities that
>would account for your gross technical ignorance.

Quoting Rick in _Casablanca_ "It's a combination of all three."

What happened Sweetcheeks, get kicked off Easynews? Bummer.

Chris Hornbeck
"History consists of truths which in the end turn into lies,
while myth consists of lies which finally turn into truths."
- Jean Cocteau

[Bob Cain]

Chris Hornbeck wrote:
> On Sat, 02 Sep 2006 02:07:08 -0000, just wondering
> > wrote:
>
>> Were you born with **** for brains or is it that you either didn't take any
>> physics/engineering courses in college or that you took them but didn't
>> learn anything from them? These are the only three possibilities that
>> would account for your gross technical ignorance.
>
> Quoting Rick in _Casablanca_ "It's a combination of all three."
>
> What happened Sweetcheeks, get kicked off Easynews? Bummer.

Indeed. He seems to want it to happen at Supernews too. Easy enough.


Bob
--

"Things should be described as simply as possible, but no simpler."

A. Einstein

[Bob Cain]

Chris Hornbeck wrote:

> If we assume the diaphragm to be "massless" we can easily
> work backwards from the behavior of low mass loudspeaker
> diaphragms, like electrostatic speakers, as dipole radiators
> in free air. Let's also assume that fundamental resonance
> is far away somewhere.

What are the mechanical elements you see as determining this
fundamental resonance? If you mean the mass/compliance resonance then
putting mass at zero moves the resonance to infinity rather than way
down low where it actually is. Not sure it is instructive to consider
the case where it's zero.

>
> At high frequencies, the diaphragm radiates into a column of
> its own shape; response anywhere on axis is just like nearfield.

It approaches that shape as you go up, yes.

> At lower frequencies radiation widens until it approaches the
> classic figure-of-eight. This is maintained indefinitely for
> all lower frequencies.

Ok.

> In the region where geometry is comparable to wavelength,
> magnitude response rings with comb filtering.

"Rings" isn't really the appropriate term. Yes, comb filtering does
occur starting where the wavelength equals the front to back distance
and goes again to zero for every integral fraction of the front to
back distance.

Are you considering another source for this comb filtering?

> Below this
> region magnitude response falls at 20dB/decade. (In ribbon
> microphones this region of falling response is the working
> range.)

Magnitude of what exactly?

> Because this behavior is a function only of size relative to
> wavelength, I believe it to apply to a "massless" freely suspended
> microphone diaphragm also, just seen from the other end of
> the telescope.

Sorry, I can't think about massless diaphragms and deduce anything
meaningful.

> Maybe a strong implication, but hardly proof, that a "mass
> rolloff", as in loudspeaker compression drivers, is the
> cause of ribbon mic high frequency final rolloff. Very
> interested in your thoughts, as always.

There is no mass rolloff because there is a falling slope of ribbon
velocity response, 20 dB/decade, which _is_ due to mass but
independant of its value, and a rising slope of he differential
pressure across it, 20 dB/decade, which exactly compensate until you
enter this comb filtering region which has nothing to do with mass.

All mass does in the ribbon mic is scale the velocity response to the
differential pressure by a constant that Feynman calls the
"coefficient of inertia", the mass.


Bob
--

"Things should be described as simply as possible, but no simpler."

A. Einstein

[Ian Bell]

just wondering wrote:


> Were you born with **** for brains or is it that you either didn't take
> any physics/engineering courses in college or that you took them but
> didn't
> learn anything from them? These are the only three possibilities that
> would account for your gross technical ignorance.

And only one that accounts for your attitude.

Ian

[just wondering]

Ian Bell > wrote in news:44f9a1f9.0@entanet:

> just wondering wrote:
>
>
>> Were you born with **** for brains or is it that you either didn't take
>> any physics/engineering courses in college or that you took them but
>> didn't
>> learn anything from them? These are the only three possibilities that
>> would account for your gross technical ignorance.
>
> And only one that accounts for your attitude.
>
> Ian
>

Apparently the same one that accounts for yours.

[just wondering]

Chris Hornbeck > wrote in
:

> On Sat, 02 Sep 2006 02:07:08 -0000, just wondering
> > wrote:
>
>>Were you born with **** for brains or is it that you either didn't
>>take any physics/engineering courses in college or that you took them
>>but didn't learn anything from them? These are the only three
>>possibilities that would account for your gross technical ignorance.
>
> Quoting Rick in _Casablanca_ "It's a combination of all three."
>
> What happened Sweetcheeks, get kicked off Easynews? Bummer.



I'm in transition, but I'll refrain from updating you with the details at
this point in time. I wouldn't want to throw any cold water on your raging
hard-on as it's probably the only one that you had since your last tryst
with god's successor on this planet.

[Chris Hornbeck]

On Fri, 01 Sep 2006 22:39:31 -0700, Bob Cain
> wrote:

>What are the mechanical elements you see as determining this
>fundamental resonance? If you mean the mass/compliance resonance then
>putting mass at zero moves the resonance to infinity rather than way
>down low where it actually is. Not sure it is instructive to consider
>the case where it's zero.

Sorry, just a device to allow my pea-brain to ignore the
mechanical resonances temporarily, enough to concentrate
on the diaphragm's motion.

>"Rings" isn't really the appropriate term. Yes, comb filtering does
>occur starting where the wavelength equals the front to back distance
>and goes again to zero for every integral fraction of the front to
>back distance.
>
>Are you considering another source for this comb filtering?

No. Again, sorry. I should have enclosed "rings" in parenthesis.
But you understand what I'm saying better than I do, so I took
liberties; bad form in a public forum; sorry.


>> Below this
>> region magnitude response falls at 20dB/decade. (In ribbon
>> microphones this region of falling response is the working
>> range.)
>
>Magnitude of what exactly?

Bingo! That is exactly the right question. Thank you so much.
I'm a "all strain, no brain" guy and get simple stuff wrong
constantly.

The analogy for diaphragm motion between ribbon mic's and
electrostatic loudspeakers is based on relative dimensions,
so should translate pretty seemlessly, but the *motors* are
different.

Dynamic, including ribbon, mic's are velocity-sensitive
(velocity=voltage), unlike voltage=amplitude electrostatics,
so will have a 20dB per decade rolloff above the geometric region.

No need to invoke any extra unmodelable mass term; just as everyone
has been saying.

I'm very Grateful (but not yet Dead) for all your help,
as always,

Chris Hornbeck
"History consists of truths which in the end turn into lies,
while myth consists of lies which finally turn into truths."
- Jean Cocteau

[[email protected]]

Just Wondering wrote:

> I'm in transition, but I'll refrain from updating you with the details at
> this point in time.

Your personal gender issues are of no concern to anyone but you.
Please refrain at any time whatsoever.

[Ian Bell]

Just Wondering wrote:

> Ian Bell > wrote in news:44f9a1f9.0@entanet:
>
>> just wondering wrote:
>>
>>
>>> Were you born with **** for brains or is it that you either didn't take
>>> any physics/engineering courses in college or that you took them but
>>> didn't
>>> learn anything from them? These are the only three possibilities that
>>> would account for your gross technical ignorance.
>>
>> And only one that accounts for your attitude.
>>
>> Ian
>>
>
> Apparently the same one that accounts for yours.

LOL. Took you quite a while to think of that world shattering response ;-)

Ian

[Ty Ford]

On Sun, 3 Sep 2006 21:33:16 -0400, Just Wondering wrote
(in article >):

> Ian Bell > wrote in news:44f9a1f9.0@entanet:
>
>> just wondering wrote:
>>
>>
>>> Were you born with **** for brains or is it that you either didn't take
>>> any physics/engineering courses in college or that you took them but
>>> didn't
>>> learn anything from them? These are the only three possibilities that
>>> would account for your gross technical ignorance.
>>
>> And only one that accounts for your attitude.
>>
>> Ian
>>
>
> Apparently the same one that accounts for yours.
>

Get a room guys. Bitch slap each other to your heart's content by direct
email, but not here.

Thaks,

Ty Ford


-- Ty Ford's equipment reviews, audio samples, rates and other audiocentric
stuff are at www.tyford.com

[just wondering]

wrote in
ups.com:

>
> Just Wondering wrote:
>
>> I'm in transition, but I'll refrain from updating you with the
>> details at this point in time.
>

> Your personal gender issues are of no concern to anyone but you.

I am sorry that your gender transition is not proceeding smoothly. It
certainly explains your present lack of proper mental function. Hopefully
your condition is temporary, and you mental capacity will eventually
return to at least a vegetative level once your hormones return to normal.

> Please refrain at any time whatsoever.


Only if you promise to do the same.

[just wondering]

Bob Cain > wrote in
:

> hris Hornbeck wrote:
>> On Sat, 02 Sep 2006 02:07:08 -0000, just wondering
>> > wrote:
>>
>>> Were you born with **** for brains or is it that you either didn't
>>> take any physics/engineering courses in college or that you took
>>> them but didn't learn anything from them? These are the only three
>>> possibilities that would account for your gross technical ignorance.
>>>
>>
>> Quoting Rick in _Casablanca_ "It's a combination of all three."
>>
>> What happened Sweetcheeks, get kicked off Easynews? Bummer.



> Indeed.

Only in your wet dreams, which apparently happen only when you are thinking
of me.


> He seems to want it to happen at Supernews too.


"It" didn't happen at Easynews, and "it" won't happen at either Supernews,
Giganews, Google or any other news provider.


Easy enough.

Knock your socks off.

>
> Bob




> "Things should be described as simply as possible, but no simpler."
>
> A. Einstein


A quote, which you attribute to Einstein, that has about as much depth as
**** on a rock, as does virtually everything that you have to say.

[[email protected]]

Just Wondering wrote:
> wrote in
> ups.com:
>
> >
> > Just Wondering wrote:
> >
> >> I'm in transition, but I'll refrain from updating you with the
> >> details at this point in time.
> >
>
> > Your personal gender issues are of no concern to anyone but you.
>
> I am sorry that your gender transition is not proceeding smoothly. It
> certainly explains your present lack of proper mental function. Hopefully
> your condition is temporary, and you mental capacity will eventually
> return to at least a vegetative level once your hormones return to normal.
>
> > Please refrain at any time whatsoever.
>
>
> Only if you promise to do the same.

Is there an echo in here? Your lame responses to people almost always
show this odd affect. Besides your gender issues, what's wrong with
you?


H.