Beeb article TLW

[geoff]

http://www.bbc.co.uk/programmes/b06tvgp1

geoff

[Les Cargill[_4_]]

geoff wrote:
> http://www.bbc.co.uk/programmes/b06tvgp1
>
> geoff

The bit involves a lot of use of terms like "intent" and "preference."

I remember the pianos from all those Brubeck records. That's
pretty much canonical now - people may not squeeze them that much,
but it's still a thing.

I can't reliably tell 320 KBPS mp3 from full linear. Perhaps that's
just a lack of training. Perhaps it's the playback chain. But in this
day and age, 320 is affordable for most connections.

--
Les Cargill

[Ralph Barone[_2_]]

geoff > wrote:
> http://www.bbc.co.uk/programmes/b06tvgp1
>
> geoff
>

The world would be an infinitesimally nicer place if dynamic range
reduction and file size reduction didn't both use the same term
"compression".

[John Williamson]

On 09/01/2016 23:56, Ralph Barone wrote:
> geoff > wrote:
>> http://www.bbc.co.uk/programmes/b06tvgp1
>>
>> geoff
>>
>
> The world would be an infinitesimally nicer place if dynamic range
> reduction and file size reduction didn't both use the same term
> "compression".
>
Certainly less misunderstood. The programme didn't even mention data
compression, apart from it's effect on delivery systems.

--
Tciao for Now!

John.

[[email protected]]

Les Cargill wrote: "I can't reliably tell 320 KBPS mp3 from full linear. Perhaps that's
just a lack of training. Perhaps it's the playback chain. But in this
day and age, 320 is affordable for most connections. "


Again, post processing will have far more audible
impact than method of conveyance(physical,
stream, etc), bit depth, sampling rate, or lossy
vs lossless.

[geoff]

On 10/01/2016 1:06 PM, John Williamson wrote:
> On 09/01/2016 23:56, Ralph Barone wrote:
>> geoff > wrote:
>>> http://www.bbc.co.uk/programmes/b06tvgp1
>>>
>>> geoff
>>>
>>
>> The world would be an infinitesimally nicer place if dynamic range
>> reduction and file size reduction didn't both use the same term
>> "compression".
>>
> Certainly less misunderstood. The programme didn't even mention data
> compression, apart from it's effect on delivery systems.
>


An unfortunate oversight. But even "data compression:" is not consice.
Data compression is lossless (ie FLAC, WavZip of old, or simply Zip).

What they (and most others) refer to as data compression is actually
"data reduction".

geoff

[Trevor]

On 10/01/2016 10:56 AM, Ralph Barone wrote:
> geoff > wrote:
>> http://www.bbc.co.uk/programmes/b06tvgp1
>>
>
> The world would be an infinitesimally nicer place if dynamic range
> reduction and file size reduction didn't both use the same term
> "compression".

I guess you better not talk about internal combustion engines either
then. :-)
The simple fact is it is up to the writer to explain what he is talking
about, and the reader to make an attempt at understanding what is
written. Both seem to be lacking in many cases unfortunately. Inventing
more words they don't understand is not going to help them.

Trevor.

[Trevor]

On 10/01/2016 2:18 PM, geoff wrote:
> On 10/01/2016 1:06 PM, John Williamson wrote:
>> On 09/01/2016 23:56, Ralph Barone wrote:
>>> geoff > wrote:
>>>> http://www.bbc.co.uk/programmes/b06tvgp1
>>>
>>> The world would be an infinitesimally nicer place if dynamic range
>>> reduction and file size reduction didn't both use the same term
>>> "compression".
>>>
>> Certainly less misunderstood. The programme didn't even mention data
>> compression, apart from it's effect on delivery systems.
>
>
> An unfortunate oversight. But even "data compression:" is not consice.
> Data compression is lossless (ie FLAC, WavZip of old, or simply Zip).
>
> What they (and most others) refer to as data compression is actually
> "data reduction".

Not exactly, data compression may be either lossy or lossless. Even
"data reduction" is not completely clear, as lossless data compression
still results in a reduction of file data, if not recovered data.
One simply must use enough words to make the intention clear when it is
deemed important enough.

Trevor.

[Don Pearce[_3_]]

On Sat, 09 Jan 2016 23:56:15 GMT, Ralph Barone
> wrote:

>geoff > wrote:
>> http://www.bbc.co.uk/programmes/b06tvgp1
>>
>> geoff
>>
>
>The world would be an infinitesimally nicer place if dynamic range
>reduction and file size reduction didn't both use the same term
>"compression".

The programme would have done well not to mention data compression at
all. It didn't contribute materially, and served only to introduce
some confusion.

d

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

[Luigi]

Ralph Barone wrote:
> The world would be an infinitesimally nicer place if dynamic range
> reduction and file size reduction didn't both use the same term
> "compression".

layman here... I've always thought 'compression' as part of the
recording process is also misleading (ie. it would be a third meaning),
as it leaves the initial attack alone and only reduces what comes after
the attack.

Or is my understanding wrong?

[Don Pearce[_3_]]

On Sun, 10 Jan 2016 11:36:40 +0000, Luigi > wrote:

>Ralph Barone wrote:
>> The world would be an infinitesimally nicer place if dynamic range
>> reduction and file size reduction didn't both use the same term
>> "compression".
>
>layman here... I've always thought 'compression' as part of the
>recording process is also misleading (ie. it would be a third meaning),
>as it leaves the initial attack alone and only reduces what comes after
>the attack.
>
>Or is my understanding wrong?

Compression is whatever you make it. If the final dynamic range is
reduced, you have compression - there is nothing intrinsic that tells
you how it must be done. That would be an "artistic" choice.

d

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

[Mike Rivers[_2_]]

On 1/9/2016 10:18 PM, geoff wrote:
> But even "data compression:" is not consice. Data compression is
> lossless (ie FLAC, WavZip of old, or simply Zip).
>
> What they (and most others) refer to as data compression is actually
> "data reduction".

But "data reduction" is the process of sorting out data and making sense
of it. In physics class in high school (1959) the teacher always said
"and now let's do the data reduction."


--
For a good time, visit http://mikeriversaudio.wordpress.com

[Luigi]

Don Pearce wrote:
>> layman here... I've always thought 'compression' as part of the
>> recording process is also misleading (ie. it would be a third meaning),
>> as it leaves the initial attack alone and only reduces what comes after
>> the attack.
>>
>> Or is my understanding wrong?
>
> Compression is whatever you make it. If the final dynamic range is
> reduced, you have compression - there is nothing intrinsic that tells
> you how it must be done. That would be an "artistic" choice.

sorry, I meant specifically another technique that is also called
'compression', the one that is part of changing the dynamics of a
recorded instrument such as drums. It is part of the effects in a
recording console; so you would have 3 different meanings of
compression: 1) lossy coding 2) dynamic range reduction 3) compression
as part of recording an instrument.

I just thought if it does what I think it does, the last one should
really be called something other than 'compression', maybe 'attack
shaping' or so?
L.

[Don Pearce[_3_]]

On Sun, 10 Jan 2016 17:54:34 +0000, Luigi > wrote:

>Don Pearce wrote:
>>> layman here... I've always thought 'compression' as part of the
>>> recording process is also misleading (ie. it would be a third meaning),
>>> as it leaves the initial attack alone and only reduces what comes after
>>> the attack.
>>>
>>> Or is my understanding wrong?
>>
>> Compression is whatever you make it. If the final dynamic range is
>> reduced, you have compression - there is nothing intrinsic that tells
>> you how it must be done. That would be an "artistic" choice.
>
>sorry, I meant specifically another technique that is also called
>'compression', the one that is part of changing the dynamics of a
>recorded instrument such as drums. It is part of the effects in a
>recording console; so you would have 3 different meanings of
>compression: 1) lossy coding 2) dynamic range reduction 3) compression
>as part of recording an instrument.
>
>I just thought if it does what I think it does, the last one should
>really be called something other than 'compression', maybe 'attack
>shaping' or so?
>L.

Attack and release are the two main settings of a compressor and they
determine the sound. Applied to drums they result in kind of pumping
effect - taken to the extreme on Phil Collins "Something in the air
tonight".

Lossy coding is another thing altogether, and I wish we could find a
different name for it to stop the confusion.

d

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

[[email protected]]

Don Pearce: Lately I have made it a forced habit to
refer to the two, respectively, as dynamic compression
and data compression. Haven't had any misunderstandings
yet!

[geoff]

On 11/01/2016 9:41 a.m., wrote:
> Don Pearce: Lately I have made it a forced habit to
> refer to the two, respectively, as dynamic compression
> and data compression. Haven't had any misunderstandings
> yet!

So do you not differentiate between normal lossless data compression as
in Zip, FLAC, etc, and data-reduction schemes such as in MP3, JPEG, etc
? Or just put them in the same big vague basket ?

geoff

[[email protected]]

geoff wrote: "So do you not differentiate between normal lossless data compression as
in Zip, FLAC, etc, and data-reduction schemes such as in MP3, JPEG, etc
? Or just put them in the same big vague basket ?

geoff "

For most conversations "dynamic compression and
"data compression" suffice. No need to subcategorize
the latter as long as both parties know which affects
loud-soft ratio and which affects file size.

[Mike Rivers[_2_]]

On 1/10/2016 3:56 PM, geoff wrote:
> So do you not differentiate between normal lossless data compression as
> in Zip, FLAC, etc, and data-reduction schemes such as in MP3, JPEG, etc
> ? Or just put them in the same big vague basket ?

For me, it depends on who I'm talking to and what they really want to
know. Those are file types (or "containers" of a sort) that are
independent of what data gets processed by the the algorithm that
produces that type file.

"Data reduced (or compressed) MP3" is redundant. It's somewhat important
to know what you're getting, or asking for, because presumably you'll
want to listen to the audio or view the picture, and not all systems
will play every format. For example, my friend has a Nissan
somethingorother that has a USB port as part of the audio system. It
will play an MP3 file from a USB thumb drive, but not a WAV file. I
don't know about other audio formats. I didn't read the manual.

--
For a good time, visit http://mikeriversaudio.wordpress.com

[Scott Dorsey]

Don Pearce > wrote:
>
>Attack and release are the two main settings of a compressor and they
>determine the sound. Applied to drums they result in kind of pumping
>effect - taken to the extreme on Phil Collins "Something in the air
>tonight".

And this compression, along with limiting, expansion, and AGC, are
special cases of the general class of "dynamics processors."

>Lossy coding is another thing altogether, and I wish we could find a
>different name for it to stop the confusion.

That's why I like to use the phrase "perceptual encoding" because it
both describes what is going on and why.
--scott

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

[geoff]

On 11/01/2016 10:31 a.m., wrote:
> geoff wrote: "So do you not differentiate between normal lossless data compression as
> in Zip, FLAC, etc, and data-reduction schemes such as in MP3, JPEG, etc
> ? Or just put them in the same big vague basket ?
>
> geoff "
>
> For most conversations "dynamic compression and
> "data compression" suffice. No need to subcategorize
> the latter as long as both parties know which affects
> loud-soft ratio and which affects file size.

Um, where did I mention anything to do with audio dynamics compression
above ?

geoff

[[email protected]]

geoff wrote: "- show quoted text -
Um, where did I mention anything to do with audio dynamics compression
above ?

geoff "

Never said that you did. I was
just spelling out plainly the terms
I thought necessary to distinguish
the two.

[geoff]

On 11/01/2016 1:28 p.m., wrote:
> geoff wrote: "- show quoted text -
> Um, where did I mention anything to do with audio dynamics compression
> above ?
>
> geoff "
>
> Never said that you did. I was
> just spelling out plainly the terms
> I thought necessary to distinguish
> the two.

"The two" were not the two I was clearly alluding to.

geoff

[[email protected]]

geoff wrote: "- show quoted text -
"The two" were not the two I was clearly alluding to.

geoff "

I know. You were differentiating
between two subtypes of data
compression: Lossy and lossless.

When folks complain about the effects
of "too much compression" on music,
most of the time it is the most audible
form - dynamic compression - they
are referring to, albeit vaguely.

To help clarify such a conversation,
I would usually ask, "Which type of
compression: Dynamic(loud to soft),
or data compression, which reduces
file size"? Such probing usually
clears things up, without needing to
delve deeper into subcategories
of the latter.

[geoff]

On 11/01/2016 2:14 p.m., wrote:
> geoff wrote: "- show quoted text -
> "The two" were not the two I was clearly alluding to.
>
> geoff "
>
> I know. You were differentiating
> between two subtypes of data
> compression: Lossy and lossless.
>
> When folks complain about the effects
> of "too much compression" on music,
> most of the time it is the most audible
> form - dynamic compression - they
> are referring to, albeit vaguely.
>
> To help clarify such a conversation,
> I would usually ask, "Which type of
> compression: Dynamic(loud to soft),
> or data compression, which reduces
> file size"? Such probing usually
> clears things up, without needing to
> delve deeper into subcategories
> of the latter.


It could be argued that "The latter" are two completely different
things, and one being a subcategory of the other.

One (ie Zip, FLAC, PCA, etc) being a mathematical process resulting in
output data identical to input data and is not specific to music or image.

The other (MP3, JPEG, etc) being a process of perceptual-based data
reduction (sorry Mike) resulting in a smaller file-size, which apart
from the misnomer is the only thing they have in common.

geoff

[geoff]

On 11/01/2016 2:32 p.m., geoff wrote:
> On 11/01/2016 2:14 p.m., wrote:
>> geoff wrote: "- show quoted text -
>> "The two" were not the two I was clearly alluding to.
>>
>> geoff "
>>
>> I know. You were differentiating
>> between two subtypes of data
>> compression: Lossy and lossless.
>>
>> When folks complain about the effects
>> of "too much compression" on music,
>> most of the time it is the most audible
>> form - dynamic compression - they
>> are referring to, albeit vaguely.
>>
>> To help clarify such a conversation,
>> I would usually ask, "Which type of
>> compression: Dynamic(loud to soft),
>> or data compression, which reduces
>> file size"? Such probing usually
>> clears things up, without needing to
>> delve deeper into subcategories
>> of the latter.
>
>
> It could be argued that "The latter" are two completely different
> things, and one being a subcategory of the other.
>
> One (ie Zip, FLAC, PCA, etc) being a mathematical process resulting
> in output data identical to input data and is not specific to music or
> image.
>
> The other (MP3, JPEG, etc) being a process of perceptual-based data
> reduction (sorry Mike) resulting in a smaller file-size, which apart
> from the misnomer is the only thing they have in common.
>
> geoff


Sorry - "and one *NOT* being a subcategory of the other."

geoff

[[email protected]]

"- show quoted text -
Sorry - "and one *NOT* being a subcategory of the other."

geoff "

Ahh. Another nit-picker in our midst. Loves
to stir the pot. Mr. Carson: the door please?

[Ralph Barone[_2_]]

Don Pearce > wrote:
> On Sat, 09 Jan 2016 23:56:15 GMT, Ralph Barone
> > wrote:
>
>> geoff > wrote:
>>> http://www.bbc.co.uk/programmes/b06tvgp1
>>>
>>> geoff
>>>
>>
>> The world would be an infinitesimally nicer place if dynamic range
>> reduction and file size reduction didn't both use the same term
>> "compression".
>
> The programme would have done well not to mention data compression at
> all. It didn't contribute materially, and served only to introduce
> some confusion.
>
> d
>
> ---
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus

I think that discussing both makes some sense because they both make music
sound terrible if overdone, and they've both been highly used lately, but
they did flip back and forth between the two types a bit too much right at
the end.

[geoff]

On 11/01/2016 3:12 p.m., wrote:
> "- show quoted text -
> Sorry - "and one *NOT* being a subcategory of the other."
>
> geoff "
>
> Ahh. Another nit-picker in our midst. Loves
> to stir the pot. Mr. Carson: the door please?

Not nits. ELEPHANTS. Not a subtle difference in the slightest.

But going on past experience, I give up.

geoff

[Phil Allison[_4_]]

Luigi wrote:

>
> layman here... I've always thought 'compression' as part of the
> recording process is also misleading (ie. it would be a third meaning),
> as it leaves the initial attack alone and only reduces what comes after
> the attack.
>
>

** Doing that results in an expansion of the dynamic range.

The old dBx160 "compressors" had a slow attack of about 25mS, allowing transients to pass unaffected while limiting steady parts of the programme.
The net result is the peak to average ratio goes UP, not down as you might expect.

The VU meter on the 160 followed the same characteristic, so hiding the fact from operators who preferred to believe their eyes instead of their ears.

Genuine peak limiters have fast attack and a fairly slow release to prevent this happening.


.... Phil

[JackA]

On Sunday, January 10, 2016 at 9:12:19 PM UTC-5, wrote:
> "- show quoted text -
> Sorry - "and one *NOT* being a subcategory of the other."
>
> geoff "
>
> Ahh. Another nit-picker in our midst. Loves
> to stir the pot. Mr. Carson: the door please?

Interesting that Metalica approved compressed sound, but fans who found the RockBand multi-tracks mixed to what they felt appropriate!! Neat!!

Jack

[JackA]

On Sunday, January 10, 2016 at 9:12:19 PM UTC-5, wrote:
> "- show quoted text -
> Sorry - "and one *NOT* being a subcategory of the other."
>
> geoff "
>
> Ahh. Another nit-picker in our midst. Loves
> to stir the pot. Mr. Carson: the door please?

About the early 60's, 35mm film audio recordings gained SOME momentum. In general, people didn't care for the higher quality sound. However, on the rear of a Mercury Record 35mm LP, they offered a standalone electronic gadget for use with their 35mm audio recordings. Does anyone know what it actually was?

http://www.angelfire.com/empire/abpsp/images/septintherain.mp3

Thanks.

Jack

[Trevor]

On 11/01/2016 1:59 PM, Phil Allison wrote:
> Luigi wrote:
>> layman here... I've always thought 'compression' as part of the
>> recording process is also misleading (ie. it would be a third
>> meaning), as it leaves the initial attack alone and only reduces
>> what comes after the attack.
>
> ** Doing that results in an expansion of the dynamic range.
>
> The old dBx160 "compressors" had a slow attack of about 25mS,
> allowing transients to pass unaffected while limiting steady parts of
> the programme. The net result is the peak to average ratio goes UP,
> not down as you might expect.
>
> The VU meter on the 160 followed the same characteristic, so hiding
> the fact from operators who preferred to believe their eyes instead
> of their ears.
>
> Genuine peak limiters have fast attack and a fairly slow release to
> prevent this happening.

I think you have missed the difference between the point of a
"compressor" and a "peak limiter" then. Models like the 160 are pretty
limited control wise unfortunately. But a "genuine peak limiter" alone
will usually have a fast release, not a "fairly slow release". You can
use a compressor for that where necessary, usually together with the
peak limiter. Proper use of controls on both (where provided) can
provide audible leveling without destroying transients, or it can
provide real dynamic range reduction as required.

Trevor.

[Phil Allison[_4_]]

Trevor wrote:

>
> >
> > ** Doing that results in an expansion of the dynamic range.
> >
> > The old dBx160 "compressors" had a slow attack of about 25mS,
> > allowing transients to pass unaffected while limiting steady parts of
> > the programme. The net result is the peak to average ratio goes UP,
> > not down as you might expect.
> >
> > The VU meter on the 160 followed the same characteristic, so hiding
> > the fact from operators who preferred to believe their eyes instead
> > of their ears.
> >
> > Genuine peak limiters have fast attack and a fairly slow release to
> > prevent this happening.
>
>
> I think you have missed the difference between the point of a
> "compressor" and a "peak limiter" then. Models like the 160 are pretty
> limited control wise unfortunately. But a "genuine peak limiter" alone
> will usually have a fast release, not a "fairly slow release". You can
> use a compressor for that where necessary, usually together with the
> peak limiter. Proper use of controls on both (where provided) can
> provide audible leveling without destroying transients, or it can
> provide real dynamic range reduction as required.
>
>

** I mentioned release time because the dbx160 ( and relatives ) has a fixed and fairly fast one - about 12db per 100mS. At this rate the gain changes during speech and also low frequency sine waves causing audible distortion which a slower release would fix.

I saw a lot of dbx160s in the 80s and 90s being used in sound reinforcement - where they were expected to keep a limit on maximum levels and prevent amplifier clipping. To this end they were used with high threshold and ratio settings while the operator kept an eye on the yellow & red LEDs plus the VU needle. This was standard practice based on faith not science - the faith deriving mainly from the fact the companies like Clair Bros used them this way. But it simply didn't work and peak levels way above the threshold setting appeared at the output constantly - plus the gain pumped.

I know that recording folk like them for the sound effect they create, particularly with bass drums, which is essentially range expansion combined with gain pumping.

An ideal peak limiter has no effect on programme until the threshold level is reached when it instantly drops the gain to keep the signal peaks below the threshold. Normal gain should be restored in about 1 second when the incoming signal level drops below the set threshold.

Units that have independent threshold, attack, release and ratio controls are versatile enough to do many tasks, including sounding just like a dbx160.

BTW;

dbx160s had another endearing characteristic, they would enter switch off muting if the AC supply voltage dropped suddenly by 10% or more. The whole FOH system would suddenly go dead for 5 seconds and then re-appear.

Drove operators mad and they never suspected their dbx160s were the cause.


..... Phil

[Trevor]

On 11/01/2016 7:00 PM, Phil Allison wrote:
> Trevor wrote:
>>>
>>> ** Doing that results in an expansion of the dynamic range.
>>>
>>> The old dBx160 "compressors" had a slow attack of about 25mS,
>>> allowing transients to pass unaffected while limiting steady
>>> parts of the programme. The net result is the peak to average
>>> ratio goes UP, not down as you might expect.
>>>
>>> The VU meter on the 160 followed the same characteristic, so
>>> hiding the fact from operators who preferred to believe their
>>> eyes instead of their ears.
>>>
>>> Genuine peak limiters have fast attack and a fairly slow release
>>> to prevent this happening.
>>
>>
>> I think you have missed the difference between the point of a
>> "compressor" and a "peak limiter" then. Models like the 160 are
>> pretty limited control wise unfortunately. But a "genuine peak
>> limiter" alone will usually have a fast release, not a "fairly slow
>> release". You can use a compressor for that where necessary,
>> usually together with the peak limiter. Proper use of controls on
>> both (where provided) can provide audible leveling without
>> destroying transients, or it can provide real dynamic range
>> reduction as required.
>>
>>
>
> ** I mentioned release time because the dbx160 ( and relatives ) has
> a fixed and fairly fast one - about 12db per 100mS. At this rate the
> gain changes during speech and also low frequency sine waves causing
> audible distortion which a slower release would fix.

Yes, the 160 is very limited in it's controls as I said. They do have
alternate ones with full control of attack and decay however.


> I saw a lot of dbx160s in the 80s and 90s being used in sound
> reinforcement - where they were expected to keep a limit on maximum
> levels and prevent amplifier clipping.

Agreed, but a poor choice for that. Budgets usually dictate using
equipment that provides as much bang for the buck as possible, not
always what is actually best for the purpose. And those that select or
use it often have no idea anyway.


> To this end they were used
> with high threshold and ratio settings while the operator kept an eye
> on the yellow & red LEDs plus the VU needle. This was standard
> practice based on faith not science - the faith deriving mainly from
> the fact the companies like Clair Bros used them this way. But it
> simply didn't work and peak levels way above the threshold setting
> appeared at the output constantly - plus the gain pumped.

Yep, no argument. Many live sound guys still do not have a proper
understanding of how the equipment actually works. If the threshold
setting is high enough though, gain pumping is often inaudible, but
agreed a faster attack is required for peak limiting. The real problem
with something like the 160 is people think they can do both compression
and peak limiting with it. The controls simply do not allow for that.


> I know that recording folk like them for the sound effect they
> create, particularly with bass drums, which is essentially range
> expansion combined with gain pumping.

Models with gating even more so.


> An ideal peak limiter has no effect on programme until the threshold
> level is reached when it instantly drops the gain to keep the signal
> peaks below the threshold. Normal gain should be restored in about 1
> second when the incoming signal level drops below the set threshold.
> Units that have independent threshold, attack, release and ratio
> controls are versatile enough to do many tasks, including sounding
> just like a dbx160.

Exactly. The 160 is pretty limited, not so all compressor/limiter/noise
gates on the market.


> BTW;
>
> dbx160s had another endearing characteristic, they would enter switch
> off muting if the AC supply voltage dropped suddenly by 10% or more.
> The whole FOH system would suddenly go dead for 5 seconds and then
> re-appear.
>
> Drove operators mad and they never suspected their dbx160s were the
> cause.

Glad I didn't have one then, although I have used many DBX products over
the years. Not sure I've ever had to put up with a 10% loss of voltage
though, not that I know of anyway. 100% loss a few times! :-(

Trevor.

[Phil Allison[_4_]]

Trevor wrote:
>
>
>
> > BTW;
> >
> > dbx160s had another endearing characteristic, they would enter switch
> > off muting if the AC supply voltage dropped suddenly by 10% or more.
> > The whole FOH system would suddenly go dead for 5 seconds and then
> > re-appear.
> >
> > Drove operators mad and they never suspected their dbx160s were the
> > cause.
>
> Glad I didn't have one then, although I have used many DBX products over
> the years. Not sure I've ever had to put up with a 10% loss of voltage
> though, not that I know of anyway. 100% loss a few times! :-(
>

** Just to be clear, the voltage drop that triggered the 160's muting system was about 20V in 240V happening suddenly and maybe briefly. You could simulate it on the bench with a Variac with a quick wrist flick.

At a venue, where the AC power was being stretched, by the lighting rig coming up fast or the refrigeration system cycling on. Running the same PA on a modest generator or on board a boat was near impossible.

Of course, a simple enough mod fixed the silly problem.


..... Phil

[Scott Dorsey]

Les Cargill > wrote:
>I remember the pianos from all those Brubeck records. That's
>pretty much canonical now - people may not squeeze them that much,
>but it's still a thing.


>
>I can't reliably tell 320 KBPS mp3 from full linear. Perhaps that's
>just a lack of training. Perhaps it's the playback chain. But in this
>day and age, 320 is affordable for most connections.
>
>--
>Les Cargill


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

[Scott Dorsey]

In article >, Luigi > wrote:
>Ralph Barone wrote:
>> The world would be an infinitesimally nicer place if dynamic range
>> reduction and file size reduction didn't both use the same term
>> "compression".
>
>layman here... I've always thought 'compression' as part of the
>recording process is also misleading (ie. it would be a third meaning),
>as it leaves the initial attack alone and only reduces what comes after
>the attack.
>
>Or is my understanding wrong?

Depends how you set it. You can do that if you want (and it's a good way
to make snares pop out). You can do the reverse too, with an exaggerated
decay and the attack almost completely chopped off. You can also set some
compressors so that they lock at level when the input is silent, so
you specifically avoid pumping up the beginning of each word or note.

There are a hell of a lot of really useful things you can do with compression.
There are, as noted, some evil things you can do too. Tools are like that.
--scott

>


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

[[email protected]]

Scott Dorsey wrote: "There are, as noted, some evil things you can do too.
Tools are like-SHHHHH Scott!!

There are some on here who get really IRKED if their
trade secrets are revealed. ;)

[None]

< thekkkma @ omnibus-brevis.edu > wrote in message
...
> Scott Dorsey wrote: "There are, as noted, some evil things you can
> do too.
> Tools are like-SHHHHH Scott!!
>
> There are some on here who get really IRKED if their
> trade secrets are revealed. ;)

And dummmmmmmm****s are tools. There's one dumb**** here who lays the
whip to his hobby horse, but all it does is decompose, because he rode
it to death long ago. Norman Bates and his mother; Dumb**** Theckma
and his hobby horse. The hobby horse was rode hard and put away dead.

FCKWAFA. AASBDFTOC.

[[email protected]]

Scott Dorsey, geoff, et al:
"< thekkkma @ omnibus-brevis.edu > wrote in message
...
- show quoted text -
And dummmmmmmm****s are tools. There's one dumb**** here who lays the
whip to his hobby horse, but all it does is decompose, because he rode
it to death long ago. Norman Bates and his mother; Dumb**** Theckma
and his hobby horse. The hobby horse was rode hard and put away dead.

FCKWAFA. AASBDFTOC."


See what I mean? This guy's obviously an
industry insider. But nice way for a "professional"
to act, eh? Probably does stuff to his clients'
projects without consulting them. Class act!
Too bad - you've been exposed, just by the
way you react on here.

[[email protected]]

> >
> >Or is my understanding wrong?
>
> Depends how you set it. You can do that if you want (and it's a good way
> to make snares pop out). You can do the reverse too, with an exaggerated
> decay and the attack almost completely chopped off. You can also set some
> compressors so that they lock at level when the input is silent, so
> you specifically avoid pumping up the beginning of each word or note.
>
> There are a hell of a lot of really useful things you can do with compression.
> There are, as noted, some evil things you can do too. Tools are like that.
> --scott
>
>

I see some of the new (digital) compressors have a new control HOLD

So for timing adj you have:

ATTACK... HOLD.... DECAY..

Setting the HOLD to 10 ms or more should prevent any distortion due to gain modulation down to 100 Hz.

M

[Don Pearce[_3_]]

On Tue, 12 Jan 2016 06:15:45 -0800 (PST), wrote:

>
>> >
>> >Or is my understanding wrong?
>>
>> Depends how you set it. You can do that if you want (and it's a good way
>> to make snares pop out). You can do the reverse too, with an exaggerated
>> decay and the attack almost completely chopped off. You can also set some
>> compressors so that they lock at level when the input is silent, so
>> you specifically avoid pumping up the beginning of each word or note.
>>
>> There are a hell of a lot of really useful things you can do with compression.
>> There are, as noted, some evil things you can do too. Tools are like that.
>> --scott
>>
>>
>
>I see some of the new (digital) compressors have a new control HOLD
>
>So for timing adj you have:
>
> ATTACK... HOLD.... DECAY..
>
>Setting the HOLD to 10 ms or more should prevent any distortion due to gain modulation down to 100 Hz.
>
>M
>

Any change of gain at any point causes distortion for the duration of
the change. The hold functions just delays its onset.

d

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

[JackA]

On Tuesday, January 12, 2016 at 9:09:34 AM UTC-5, wrote:
> Scott Dorsey, geoff, et al:
> "< thekkkma @ omnibus-brevis.edu > wrote in message
> ...
> - show quoted text -
> And dummmmmmmm****s are tools. There's one dumb**** here who lays the
> whip to his hobby horse, but all it does is decompose, because he rode
> it to death long ago. Norman Bates and his mother; Dumb**** Theckma
> and his hobby horse. The hobby horse was rode hard and put away dead.
>
> FCKWAFA. AASBDFTOC."
>
>
> See what I mean? This guy's obviously an
> industry insider. But nice way for a "professional"
> to act, eh? Probably does stuff to his clients'
> projects without consulting them. Class act!
> Too bad - you've been exposed, just by the
> way you react on here.

I have to admit, I enjoy his use of, "short bus". Use it myself now. See, usenet is of value!!

Jack :)

[JackA]

On Tuesday, January 12, 2016 at 9:31:29 AM UTC-5, Don Pearce wrote:
> On Tue, 12 Jan 2016 06:15:45 -0800 (PST), wrote:
>
> >
> >> >
> >> >Or is my understanding wrong?
> >>
> >> Depends how you set it. You can do that if you want (and it's a good way
> >> to make snares pop out). You can do the reverse too, with an exaggerated
> >> decay and the attack almost completely chopped off. You can also set some
> >> compressors so that they lock at level when the input is silent, so
> >> you specifically avoid pumping up the beginning of each word or note.
> >>
> >> There are a hell of a lot of really useful things you can do with compression.
> >> There are, as noted, some evil things you can do too. Tools are like that.
> >> --scott
> >>
> >>
> >
> >I see some of the new (digital) compressors have a new control HOLD
> >
> >So for timing adj you have:
> >
> > ATTACK... HOLD.... DECAY..
> >
> >Setting the HOLD to 10 ms or more should prevent any distortion due to gain modulation down to 100 Hz.
> >
> >M
> >
>
> Any change of gain at any point causes distortion for the duration of
> the change.


But how little distortion can humans detect? And, let's say it's an electric guitar, how can you tells it's distorted when distortion is already added, say by Jimi Hendrix?

Personally, I see the value of compression for those who mix audio tracks.

Jack

> The hold functions just delays its onset.
>
> d
>
> ---
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus

[Angus Kerr]

There are many uses for compression - effect, and convenience. Distortion is pretty much the same.

I used to do tracking with some compression. One artist that I recorded - played acoustic guitar, and he used to hit the body and smash the strings and do all sorts of stuff that no matter what I did with the gain, would max out the converters and get digital clipping. So I ran his track through a compressor with a high threshold, fast attack and fast release and high ratio, so that the majority of his performance was uncompressed - passed straight through essentially, yet the loud bits didn't clip my converters. Which is really a peak limiter.

For effects, you can use a compressor to pump, wheeze, distort, whatever you want.

For mixing, say a dense rock track, you would need to compress the vocals fairly heavily so that they 'sit' in the mix. You will find that without compression, you need to ride the fader or program fader automation to get the vocal to sit right. I think the art to vocals is to compress them in a way that they do not sound compressed, so they sound airy and natural. Compressing tends to change the character of the sound of the instrument though. However, uncompressed tracks in a dense mix of distorted guitars tend to pop up and down in the mix because the underlying instrumentation is already compressed. Singing particularly is a very dynamic, so compression is justified. It does produce a thickness to the sound.

However, in a airy jazzy track with a good singer who knows how to control their dynamics, you might find that light to no compression may do the trick.

Distortion, is another issue.

What I think they mean by 'distortion' is that the compressed version of the mixed track is substantially, audibly different from the final mix, in not a good way. The final released version of the product sounds very different to the mix that the producer signed off on. Distorted electric guitar on the other hand, is an intentional part of the track and arrangement. Nothing sounds better to me than a guitar amplifier where the tubes are just starting to get tickled into crunching slightly. But this distortion is part of the mix.

Lars's drums imho sound like cardboard being hit with a lead filled sock in the example in the article. To my ears, the overall sound definitely diverged and had way less punch than the GH version. But, hey, if you've been beating those drums in a metal band for the last thirty years, maybe you just can't hear that...

-A.

[[email protected]]

On Tuesday, January 12, 2016 at 9:31:29 AM UTC-5, Don Pearce wrote:
> On Tue, 12 Jan 2016 06:15:45 -0800 (PST), wrote:
>
> >
> >> >
> >> >Or is my understanding wrong?
> >>
> >> Depends how you set it. You can do that if you want (and it's a good way
> >> to make snares pop out). You can do the reverse too, with an exaggerated
> >> decay and the attack almost completely chopped off. You can also set some
> >> compressors so that they lock at level when the input is silent, so
> >> you specifically avoid pumping up the beginning of each word or note.
> >>
> >> There are a hell of a lot of really useful things you can do with compression.
> >> There are, as noted, some evil things you can do too. Tools are like that.
> >> --scott
> >>
> >>
> >
> >I see some of the new (digital) compressors have a new control HOLD
> >
> >So for timing adj you have:
> >
> > ATTACK... HOLD.... DECAY..
> >
> >Setting the HOLD to 10 ms or more should prevent any distortion due to gain modulation down to 100 Hz.
> >
> >M
> >
>
> Any change of gain at any point causes distortion for the duration of
> the change. The hold functions just delays its onset.
>
> d
>
>
A compressor creates distortion when the gain is changing __at the same frequency__ as the sine it is controlling. This obviously creates 2nd order.
ie if the signal is 100Hz and the gain is changing in step with the 100Hz, that is non-linear harmonic distortion that creates harmonics.

If the HOLD feature is implemented correctly, during the duration of the tone, the gain isn't changing. HOLD is like a retriggerable one shot....so no distortion.

After the tone ends, and after the HOLD time expires, during the decay time, the gain is increasing but at a steady rate not at a cyclic rate so again there should be no distotion.

I'm assuming the HOLD is set for a durarion longer than the lowest frequency.


I'm using the term distortion here in the pure sense i.e. harmonic distortion.
Squashing of the dymaic range may be good or bad but technically it isn't harmonic distortion.

M

[Don Pearce[_3_]]

On Wed, 13 Jan 2016 11:29:11 -0800 (PST), wrote:

>On Tuesday, January 12, 2016 at 9:31:29 AM UTC-5, Don Pearce wrote:
>> On Tue, 12 Jan 2016 06:15:45 -0800 (PST), wrote:
>>
>> >
>> >> >
>> >> >Or is my understanding wrong?
>> >>
>> >> Depends how you set it. You can do that if you want (and it's a good way
>> >> to make snares pop out). You can do the reverse too, with an exaggerated
>> >> decay and the attack almost completely chopped off. You can also set some
>> >> compressors so that they lock at level when the input is silent, so
>> >> you specifically avoid pumping up the beginning of each word or note.
>> >>
>> >> There are a hell of a lot of really useful things you can do with compression.
>> >> There are, as noted, some evil things you can do too. Tools are like that.
>> >> --scott
>> >>
>> >>
>> >
>> >I see some of the new (digital) compressors have a new control HOLD
>> >
>> >So for timing adj you have:
>> >
>> > ATTACK... HOLD.... DECAY..
>> >
>> >Setting the HOLD to 10 ms or more should prevent any distortion due to gain modulation down to 100 Hz.
>> >
>> >M
>> >
>>
>> Any change of gain at any point causes distortion for the duration of
>> the change. The hold functions just delays its onset.
>>
>> d
>>
>>
>A compressor creates distortion when the gain is changing __at the same frequency__ as the sine it is controlling. This obviously creates 2nd order.
>ie if the signal is 100Hz and the gain is changing in step with the 100Hz, that is non-linear harmonic distortion that creates harmonics.
>
>If the HOLD feature is implemented correctly, during the duration of the tone, the gain isn't changing. HOLD is like a retriggerable one shot....so no distortion.
>
>After the tone ends, and after the HOLD time expires, during the decay time, the gain is increasing but at a steady rate not at a cyclic rate so again there should be no distotion.
>
>I'm assuming the HOLD is set for a durarion longer than the lowest frequency.
>
>
>I'm using the term distortion here in the pure sense i.e. harmonic distortion.
>Squashing of the dymaic range may be good or bad but technically it isn't harmonic distortion.
>
>M

Sorry, but no. If the gain is changing, then the instantaneous voltage
one cycle later is not what it should be for linear operation. It
doesn't matter what the rate is. The result of this is that for the
duration of gain change, there is distortion. And I am also talking
about real distortion that produces harmonics and intermods.

d

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

[[email protected]]

> Sorry, but no. If the gain is changing, then the instantaneous voltage
> one cycle later is not what it should be for linear operation. It
> doesn't matter what the rate is. The result of this is that for the
> duration of gain change, there is distortion. And I am also talking
> about real distortion that produces harmonics and intermods.
>
> d
>
Don..

OK I guess we will have to agree to disagree.

If you take a pure 100 Hz sine wave and put it through an ideal VCA that is changing gain at a steady rate of say 1 dB per second (with no 100 Hz component in the control), then no 200 Hz component will be generated and I would call that no distortion.

Mark

[Don Pearce[_3_]]

On Wed, 13 Jan 2016 13:32:36 -0800 (PST), wrote:

>
>> Sorry, but no. If the gain is changing, then the instantaneous voltage
>> one cycle later is not what it should be for linear operation. It
>> doesn't matter what the rate is. The result of this is that for the
>> duration of gain change, there is distortion. And I am also talking
>> about real distortion that produces harmonics and intermods.
>>
>> d
>>
>Don..
>
>OK I guess we will have to agree to disagree.
>
>If you take a pure 100 Hz sine wave and put it through an ideal VCA that is changing gain at a steady rate of say 1 dB per second (with no 100 Hz component in the control), then no 200 Hz component will be generated and I would call that no distortion.
>
>Mark
>

You're right, there will be no 200Hz. The harmonic output is odd order
- so 300, 500 etc.

I've generated a pure 100Hz tone in Audition. Here are two pictures -
the first is tone with its spectrum as generated, and the second with
a steady, regular fade. You will see the difference:

http://www.soundthoughts.co.uk/look/no_fade.png
http://www.soundthoughts.co.uk/look/fade.png

d

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

[Phil Allison[_4_]]

wrote:
>
> >
> > I've generated a pure 100Hz tone in Audition. Here are two pictures -
> > the first is tone with its spectrum as generated, and the second with
> > a steady, regular fade. You will see the difference:
> >
> > http://www.soundthoughts.co.uk/look/no_fade.png
> > http://www.soundthoughts.co.uk/look/fade.png
> >
> >
> Wow interesting..
> I hadn't considered the 3rd and odd orders.
> The pics were a great way to demonstrate the point!
>
> So I leaned something new today...
>
> A STEADY rates of gain change, casues no EVEN order,
> but it DOES cause odd order distortion.
>

** But as the pics show, a slow fade produces inaudible (ie -108dB ) amounts of odd harmonics. It sounds completely clean - like a slow fade.

Far more concerning are the gain changes that happen during each cycle at low frequencies( ie 50Hz ) if the release time is not long enough. Distortion of the wave shape is highly audible, up to 30%.

Put simply, compressors see low frequency waves as a varying amplitude audio signals and try to compress them, which alters the wave shape.


.... Phil

[Scott Dorsey]

> wrote:
>
>> Sorry, but no. If the gain is changing, then the instantaneous voltage
>> one cycle later is not what it should be for linear operation. It
>> doesn't matter what the rate is. The result of this is that for the
>> duration of gain change, there is distortion. And I am also talking
>> about real distortion that produces harmonics and intermods.
>>
>Don..
>
>OK I guess we will have to agree to disagree.
>
>If you take a pure 100 Hz sine wave and put it through an ideal VCA that is changing gain at a steady rate of say 1 dB per second (with no 100 Hz component in the control), then no 200 Hz component will be generated and I would call that no distortion.

The effect Don is describing is real, and it's most evident when you have
a lot of sharp transients and a lot of bass in the same signal, and
compression results in the transients modulating the bass. You have to
set the compressor fast enough to respond to the transient but when you
do that, you get the distortion on the bottom end. Ironically the more
accurate the curve on the compressor the worse the distortion seems.
--scott

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

[Don Pearce[_3_]]

On Wed, 13 Jan 2016 18:52:43 -0800 (PST), Phil Allison
> wrote:

wrote:
>>
>> >
>> > I've generated a pure 100Hz tone in Audition. Here are two pictures -
>> > the first is tone with its spectrum as generated, and the second with
>> > a steady, regular fade. You will see the difference:
>> >
>> > http://www.soundthoughts.co.uk/look/no_fade.png
>> > http://www.soundthoughts.co.uk/look/fade.png
>> >
>> >
>> Wow interesting..
>> I hadn't considered the 3rd and odd orders.
>> The pics were a great way to demonstrate the point!
>>
>> So I leaned something new today...
>>
>> A STEADY rates of gain change, casues no EVEN order,
>> but it DOES cause odd order distortion.
>>
>
>** But as the pics show, a slow fade produces inaudible (ie -108dB ) amounts of odd harmonics. It sounds completely clean - like a slow fade.
>
> Far more concerning are the gain changes that happen during each cycle at low frequencies( ie 50Hz ) if the release time is not long enough. Distortion of the wave shape is highly audible, up to 30%.
>
>Put simply, compressors see low frequency waves as a varying amplitude audio signals and try to compress them, which alters the wave shape.
>
>
>... Phil

Yes, you really need to understand your sources and match the attack
and release to the lowest frequencies. A rule of thumb might be
minimum ten times 1/f at each end. A lot of sources won't allow that,
but it is amazing how much low cut you can get away with without any
loss of fidelity.

d

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

[Scott Dorsey]

Don Pearce > wrote:
>>Put simply, compressors see low frequency waves as a varying amplitude audio signals and try to compress them, which alters the wave shape.
>
>Yes, you really need to understand your sources and match the attack
>and release to the lowest frequencies. A rule of thumb might be
>minimum ten times 1/f at each end. A lot of sources won't allow that,
>but it is amazing how much low cut you can get away with without any
>loss of fidelity.

Well, that is the point of two-band compression.... you can have one speed
on the low end which is slow enough not to have substantial distortion, but
on the other hand you can have a faster compressor on the top end and not have
it affected by low frequencies. Reduced distortion on the bottom end, no
"pumping with the beat" on the top end. Very useful for things like
automatic gain controls and slow gain-riding systems which have wideband
program material going through them.
--scott

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