[Mr.T]

"Randy Yates" wrote in message
...
Why trust intuition when objective measurement is possible without
a whole lot of effort?

Yes measurements are usually very easy. Calibrating them so they actually
have some meaning has proven more difficult for you it seems.

MrT.

[Mr.T]

"isw" wrote in message
...
But that said, what I was talking about earlier was not that 115 dB was
not loud -- of course it is -- but only that 115 dB of *clean* sound is
not perceived as being as loud as 115 dB of distorted sound. Perhaps the
reason you think that level is so loud is because you're hearing
distortion.

Not me, I don't like distortion either. I once owned a JBL Paragon, so I'm
not unfamiliar with horn loaded systems, their capabilities, and
limitations. There are better ways of achieving high SPL, low distortion,
and linear frequency response these days though.

Of course, even when the *average* output level is more reasonable,
triple-forte peaks can rise into the 110+ dB region pretty easily, and I
don't like it when speakers clip any more than I do when amplifiers do
it. Klipshorns won't even break a sweat at that level, and neither will
the amplifiers that are driving them.

Nor will many other systems. Let's not compare K-Horns to el cheapo 2 way 6"
woofer boxes though!

All speakers -- more correctly all *types* of speakers -- have their
problems and their strong points. You decide what's important to you and
what makes sense to you, and then you make your choice.

Something we agree on it seems.

I prefer the
characteristics of bipolar radiators and horns (they have a lot in
common) much more than direct radiators.

Your perogitive.

YMMV.

Indeed.

MrT.

[Mr.T]

"isw" wrote in message
...
Even with efficient speakers, it's interesting just how big an amplifier
is needed to avoid clipping on peaks. That problem was bad enough with
vinyl source, and it's far worse with the extended dynamic range of CDs.

Well it might be *IF* CD's actually used more dynamic range, but even then
the problem is with your background noise floor, peaks over 115dB are still
not really required unless you are, or want to be stone deaf. In that case
however, it is far easier to achieve the desired result with good
headphones, and your neighbours won't be calling the police!

MrT.

[Eeyore]

Bret Ludwig wrote:

because most classic designs were
iteratively tweaked to run with amps with high output impedances, or in
some cases off 70 or 100 volt distribution and stepdown transformers,
this is an improvement sometimes.

That is complete garbage !

Graham

[Eeyore]

isw wrote:

Even with efficient speakers, it's interesting just how big an amplifier
is needed to avoid clipping on peaks. That problem was bad enough with
vinyl source, and it's far worse with the extended dynamic range of CDs.

Really ?

Do tell more.

Graham

[Eeyore]

"Mr.T" wrote:

"Randy Yates" wrote

Why trust intuition when objective measurement is possible without
a whole lot of effort?

Yes measurements are usually very easy. Calibrating them so they actually
have some meaning has proven more difficult for you it seems.

Making the relevant measurements requires considerable knowledge too.

Graham

[Eeyore]

isw wrote:

Eeyore wrote
isw wrote:

One of the interesting things about speakers that are capable of
reproducing high volume levels *cleanly*, is that they don't sound as
loud when compared to less-capable speakers.

This is absolutely true. The same can be said about the amplifier too.

DJs often seem to like running their systems into clipping since it sounds
'louder'.

It's infuriating.

Paul Klipsch used to tell a story about that. Seems he was demo'ing a
pair of his horns to a rock group, using a pair of 100 watt Futtermans
to drive them. The band said the sound was very nice, but not loud
enough (!).

Paul told the local dealer to take the guys to lunch while he worked on
the problem.

When they came back, he ran the demo again, the band guys clapped their
hands over their ears, and yelled "Wonderful. But turn it down; it's way
too loud now!"

Paul had replaced the Futtermans with a pair of ten-watt PA amps, and
added back-to-back diodes across the inputs to ensure the signal was
heavily clipped (and so severely distorted).

Crazy isn't it ?

You may be interested to know that I reckon the very best high SPL 'PA' systems
for bands were actually in the late 1970s.

I well recall a superlative sound in the local 'arena' for Manfred Mann's
Earthband using a Martin rig with their classic huge 'W bins' in fair numbers.

I was knocked out by the clarity of the sound but I only realised just how loud
it was when ( on the balcony no less, at some distance from the stage - easily
50 feet ) I turned to talk to my girlfriend and she couldn't hear me ! There was
no sense whatever of a 'nasty sound'. It was quite awesome.

In more modern times 'PA' aka SR rigs ( as we call them now ) concentrate on
being as light as possible for fast rigging and de-rigging so as to please the
bean counters. They're a shadow of their former best examples.

Graham

[Randy Yates]

"Mr.T" MrT@home writes:

"Randy Yates" wrote in message
...
Why trust intuition when objective measurement is possible without
a whole lot of effort?

Yes measurements are usually very easy. Calibrating them so they actually
have some meaning has proven more difficult for you it seems.

False.

What is true is that I do sometimes have difficulty identifying a
troll, especially when they masquerade as a rational person who in
reality is simply waiting for the opportune moment to make a
derrogatory assault.
--
% Randy Yates % "Midnight, on the water...
%% Fuquay-Varina, NC % I saw... the ocean's daughter."
%%% 919-577-9882 % 'Can't Get It Out Of My Head'
%%%% % *El Dorado*, Electric Light Orchestra
http://home.earthlink.net/~yatescr

[Arny Krueger]

"Eeyore" wrote in
message
isw wrote:

Even with efficient speakers, it's interesting just how
big an amplifier is needed to avoid clipping on peaks.
That problem was bad enough with vinyl source, and it's
far worse with the extended dynamic range of CDs.

Really ?

Being an old coot, I had about 25 years experience living with old tech
equipment and LPs.

In the days of 30 wpc tube power amps, most speakers were only about 90 dB/w
efficient. 30 watts is about 15 dBw so even if you sat right on top of the
speakers (1 meter) 105 dB was about it. 105 dB is only about 60 dB above a
typical household noise level, so 60 dB was about it for dynamic range. A
really quiet LP can beat that by about maybe 5 dB.

Again, this presumed you sat right on top of the speakers, which is
generally impractical. In practice, it took more like 100 dB/w speakers to
actually exploit the dynamic range of a really good LP, presuming you used
typical tubed power amps.

While we have a lot of 85 dB/w speakers, 90 dB/w and even 95 dB/w speakers
are a practical reality. 95 dB/w speakers that can handle 100s of watts,
maybe even a killowatt or more, for musically-significant amounts of time
are also a practical reality. 1,000 watts is 30 dBw, so now SPLs on the
order of 125 dB are thinkable. Working against residential background noise
levels, upwards of 80 dB dynamic range are possible.

While 125 dB SPL sounds like a recipe for ear damage, if the system has
signfiicant response in the octave below 30 Hz, it is not as dangerous as
some might think.

At least with the larger home audio systems, we've moved well past anything
that was thinkable with the LP format, but are still well within the limits
of the CD audio format.

In fact, we're square up against the dynamic range limits of real-world live
music, and the best venues for recording, which is more like 75 dB or less.

[Arny Krueger]

"isw" wrote in message

In article
. com,
"Bret Ludwig" wrote:

Peter Larsen wrote:
Karl Uppiano wrote:

If anything, the problem with my old ElectroVoice
SP12B-based building-block speakers is that they are
too sensitive for today's high-powered amplifiers.

A 12 dB attenuator on the input of the power amp, or
after the volume control if an integrated, can be very
useful.

Now this quote make more sense: "What this country
needs is a good 5-watt amplifier" -- Paul Klipsch


In many cases when working with horn loudspeakers and
very big modern amplifiers the place for the pad is
between amp and speaker. This reduces the damping
factor, but because most classic designs were
iteratively tweaked to run with amps with high output
impedances, or in some cases off 70 or 100 volt
distribution and stepdown transformers, this is an
improvement sometimes.

Damping factor is not particularly important to any
speaker, and that is even more true of horns. According
to Beranek, horns perform best (and most efficiently)
when driven from a matched impedance source.

Beranek never had the final word in audio technology. With due respect to a
great man, Beranek's most important contributions were to architectural
acoustics.

By my own test, a Klipschorn (not a "perfect" horn)
delivers equal output whether driven directly from a
low-impedance amplifier, or with a 16 ohm resistor in
series.

Makes sense, because output is more likely to be limited by the mechanics of
the driver and its enclosure + wavguide. However, this does not address
frequency response which is also important.

Fact of the matter is that Klipsch horns should not be confused with the
modern art in subwoofers. The most effective K-horn-based system that I am
familiar with was *modernized* with a large direct-radiator subwoofer more
than 10 years ago.

[Edwin Hurwitz]

In article ,
isw wrote:

In article ,
"Mr.T" MrT@home wrote:

"Bret Ludwig" wrote in message
ups.com...
In many cases when working with horn loudspeakers and very big modern
amplifiers the place for the pad is between amp and speaker.

But then you need high power resistors or a jug element or something that
can handle the extra power you feel it is necessary to dissipate.
Far better, cheaper and easier just to use a lower power amp in the first
place.

Even with efficient speakers, it's interesting just how big an amplifier
is needed to avoid clipping on peaks. That problem was bad enough with
vinyl source, and it's far worse with the extended dynamic range of CDs.

Isaac

I would agree with that if most of my CDs had anywhere near the dynamic
range of most of my vinyl. It's beyond ironic that now that we have a
delivery medium capable of realistic dynamic range, everything is
squashed to within an inch of its life.

Edwin

[[email protected]]

Bret Ludwig wrote:
Eeyore wrote:
Bret Ludwig wrote:

because most classic designs were
iteratively tweaked to run with amps with high output impedances, or in
some cases off 70 or 100 volt distribution and stepdown transformers,
this is an improvement sometimes.

That is complete garbage !

I first heard rumors to this effect roughly 20 years ago, because a
local Klipsch/Mcintosh dealer got caught putting L-padding inside
K-horns so the Mc meter needles would show some responnse in his small
demo rooms without driving the suckers, i mean clients, out. Repeated
experiments have proven it true. It sometimes improves the overall
sound of horn speakers when huge outsize amps are used, either by
making the amps work harder or by cutting the damping factor or both.

Or, more likely, having a significant source impedance
driving a most assuredly non-flat impedance results in
a significant change in the frequency response. Theories
like "making the amp work harder" and such, to put it
bluntly, are nonsense.

The fact is that the overall frequency response of the
speakers WILL change, and most likely in an audible
fashion. That alone is more than sufficient to explain
any differences.

[Mr.T]

"Arny Krueger" wrote in message
. ..
While 125 dB SPL sounds like a recipe for ear damage, if the system has
signfiicant response in the octave below 30 Hz, it is not as dangerous as
some might think.

The number of speakers that can produce 125dB at 30Hz is severely limited!
(and certainly not the K-Horns)
Regardless, 125dB SPL's *are* a recipe for ear damage, unless you are
seriously suggesting that someone should buy a system just to do it once as
a party trick?

MrT.

[Mr.T]

"Eeyore" wrote in message
...
Why trust intuition when objective measurement is possible without
a whole lot of effort?

Yes measurements are usually very easy. Calibrating them so they
actually
have some meaning has proven more difficult for you it seems.

Making the relevant measurements requires considerable knowledge too.

Not at all. Simply turning on a RS meter and reading the figures displayed
requires no skill at all.
Understanding what you are actually measuring, measurement uncertainty,
sources of error etc is what requires knowledge. But that's not something
that has been considered in the current discussion from what I have read.

MrT.

[Mr.T]

"Randy Yates" wrote in message
...
Why trust intuition when objective measurement is possible without
a whole lot of effort?

Yes measurements are usually very easy. Calibrating them so they
actually
have some meaning has proven more difficult for you it seems.

False.

No evidence shown of any test procedures, calibration data or measurement
uncertainties given, that I have seen?

MrT.

[Mr.T]

"Edwin Hurwitz" wrote in message
...
I would agree with that if most of my CDs had anywhere near the dynamic
range of most of my vinyl. It's beyond ironic that now that we have a
delivery medium capable of realistic dynamic range, everything is
squashed to within an inch of its life.

It's simply because the rest of the system used by most people for listening
can not handle 90dB+ dynamic range, and they wouldn't want that much even if
it could.
But I do agree modern music seems to have gone much too far the other way.

MrT.

[isw]

In article ,
Eeyore wrote:

isw wrote:

Eeyore wrote
isw wrote:

One of the interesting things about speakers that are capable of
reproducing high volume levels *cleanly*, is that they don't sound as
loud when compared to less-capable speakers.

This is absolutely true. The same can be said about the amplifier too.

DJs often seem to like running their systems into clipping since it
sounds
'louder'.

It's infuriating.

Paul Klipsch used to tell a story about that. Seems he was demo'ing a
pair of his horns to a rock group, using a pair of 100 watt Futtermans
to drive them. The band said the sound was very nice, but not loud
enough (!).

Paul told the local dealer to take the guys to lunch while he worked on
the problem.

When they came back, he ran the demo again, the band guys clapped their
hands over their ears, and yelled "Wonderful. But turn it down; it's way
too loud now!"

Paul had replaced the Futtermans with a pair of ten-watt PA amps, and
added back-to-back diodes across the inputs to ensure the signal was
heavily clipped (and so severely distorted).

Crazy isn't it ?

You may be interested to know that I reckon the very best high SPL 'PA'
systems
for bands were actually in the late 1970s.

I well recall a superlative sound in the local 'arena' for Manfred Mann's
Earthband using a Martin rig with their classic huge 'W bins' in fair
numbers.

I was knocked out by the clarity of the sound but I only realised just how
loud
it was when ( on the balcony no less, at some distance from the stage -
easily
50 feet ) I turned to talk to my girlfriend and she couldn't hear me ! There
was
no sense whatever of a 'nasty sound'. It was quite awesome.

I've done the same thing in my living room, when a friend brought over a
Crown DC-400. He thought something was wrong with it because when he
drove it to clipping on his Bose 901's, it still wasn't all that loud.

After I hooked it to the K-Horns, he went out and bought some real
speakers.

Isaac

[isw]

In article om,
"Bret Ludwig" wrote:

Eeyore wrote:
Bret Ludwig wrote:

because most classic designs were
iteratively tweaked to run with amps with high output impedances, or in
some cases off 70 or 100 volt distribution and stepdown transformers,
this is an improvement sometimes.

That is complete garbage !

I first heard rumors to this effect roughly 20 years ago, because a
local Klipsch/Mcintosh dealer got caught putting L-padding inside
K-horns so the Mc meter needles would show some responnse in his small
demo rooms without driving the suckers, i mean clients, out. Repeated
experiments have proven it true. It sometimes improves the overall
sound of horn speakers when huge outsize amps are used, either by
making the amps work harder or by cutting the damping factor or both.
However, using a properly gauged amp works even better.

Unfortunately, in many cases that works because so many amplifiers have
very poor distortion performance at very low levels. Published numbers
are often measured at near-maximum power, and some mechanisms that cause
distortion are nearly constant, regardless of output power (crossover
distortion is one such). At high output, the contribution is minuscule,
but at low output it becomes very significant. Padding the output gets
the amp up out of its nonlinear region.

Back in the late 60's, I designed my own power amplifier to use with
K-Horns for exactly that reason. The one I did showed well under 0.1% IM
and THD at less than 25 milliwatts, even though it was capable of near
50 watt output.

Isaac

[Peter Larsen]

Bret Ludwig wrote:

[my comment]

A 12 dB attenuator on the input of the power amp, or after
the volume control if an integrated, can be very useful.

In many cases when working with horn loudspeakers and very
big modern amplifiers the place for the pad is between amp
and speaker. This reduces the damping factor, but because
most classic designs were iteratively tweaked to run with amps
with high output impedances, or in some cases off 70 or 100 volt
distribution and stepdown transformers, this is an improvement
sometimes.

Hmmm ... thanks, interesting concept.


Merry Christmas

Peter Larsen