Pyschoacoustics and the LAS vs. Khorn debate

[edwinr]

Hey, Doc. I really enjoy your posts and I always make a point of seeking out any threads you have written in. While I like the way you write, I enjoy looking for holes in your argument. I understand the thrust of what you are saying vis a vis measurement verses black magic. I can see the scientist coming out when you attempt to explain what you are hearing by applying a model or even a mathematical description to explain an anomaly. But you admit the acoustic models we are discussing are imperfect...

Moving along, my suggestion is that acoustic models and relevant measurment methodology may be difficult to apply to the Klipschorn. The graphs and specifications that have been thrust at us by Klipsch (?) appear, not misleading, but... incomplete. There is no frame of reference for me to read and understand how these graphs relate to the Klipschorn - and certainly not what I have heard in my home. If you pull the Klipschorn out of it's room for measurement, it's like pulling a motor out of a car - measuring the power output of the motor in isolation is not going to tell you how fast the car will lap a racetrack. There are lots of other considerations.

So why do manufacturers include what I consider to be meaningless specifications and graphs in their product blurb? Maybe the public expect that. Maybe they like to compare specifications without actually listening.

Allow me to raise the low powered SET amplifier debate which has raged on in these pages for an eternity, and will continue to do so. Amplifier topology aside, I am a keen supporter of 'more power is better' when driving Klipschorns and La Scalas. My ears tell me that the Klipschorns responds very well to more power than most SET amplifiers can provide.

BUT, to merely look at the specifications that most SET amplifiers feature, and then discount them because of the published figures, is to do well designed SET amplifiers an injustice. I have heard things with SET amplifiers driving very sensitive horn loaded loudspeakers, that cannot be fully explained by measurements alone.

Is it because the measurements provided are inadequate? Is it because we don't know how to measure what we hear? Or is it because we don't know what to measure? Is it all three?

[DrWho]

...Is it because the measurements provided are

inadequate? Is it because we don't know how to measure what

we hear? Or is it because we don't know what to measure? Is

it all three?

I must confess that is one of the things that drives my interest in

audio...It's a most fascinating topic and the best part is you're

likely wrong in the end anyway. (but who cares if it sounds good,

right?) [H]

[Loudisbeautiful]

Hi all.....great thread,

OK.....This is how Brain Cheney (who's work I respect very much) of VMPS hears horns:

Other people in the High End insist on resurrecting old technology and promoting it as new technology. In speakers, this means above all, HORNS. Bruce Edgar builds a $20,000 horn, that French outfit a $65,000 horn. Horns?? With phenolic drivers? Many milliseconds of delay? The megaphone effect (reflections within the horn throat that make everybody sound like Rudy Vallee)? Yes, the efficiency is amazing, as is the sound pressure. Yes its impactful and sounds better with those 5 Watt single-ended triode power amps. Yes the overall sound quality is marginal to dreadful. No, theres nothing you can do about it: change the driver, change the horn throat, equalize, use better materials. Nothing really helps. Dont listen to horns, theyre bad for your aural health.

Reference: http://www.vmpsaudio.com/dc32.htm

Personally, the dynamic impact of a horn and the emotional content is worth the slight horn effect.....

Now can this indeed be modeled into a computer program and measured?.......

[Rivendell61]

Jeff,

I see the 'throat distortion' comments on lots of other forums when ever horns come up. What I would be interested in is some actual quantification of it. We know all speakers have distortions.

Mark

[DrWho]

The way I've come to understand it is horn theory relies on the air

behaving like an ideal gas (you know, a "pure simple compressible

substance"). It's an assumption made to make the math a whole heck of a

lot easier. Anyways, the model doesn't hold true because there is

friction along the edges of the horn and the air doesn't compress

linearly. You've got the venturri principle to worry about and the

pressure on each side of the horn throat is always changing, so the air

in the middle "gets confused" (gets turbulent). There's some other

factors too, but it was so long ago and I'm probably already butchering

the article I read. I'll have to go see if I can find it again.

But in the end, horn throat distortion is something that can be greatly

minimized....like reduced to a level far below any of the other

distortions (which are also greatly reduced by the presence of the

horn).

It sounds to me like that Cheney bloke is trying to sell something...oh wait, he actually is. go figure

(if anything is "2D" sounding it would be those ribbon tweeters he's using...) []