Peter Aczel's Audio Legacy

[Swtoby]

I wonder, does anyone have any info on why he was against “monkey coffins”? Would be interesting to understand his reasoning.

From the Audio Critic webzine: "Loudspeakers are the only sector of audio where significant improvements are still possible and can be expected. I suspect that (1) further refinements of radiation pattern will result in the largest sonic benefits and (2) powered loudspeakers with electronic crossovers will end up being preferred to passive-crossover designs. In any case, one thing I am fairly sure of: No breakthrough in sound quality will be heard from “monkey coffins” (1970s trade lingo), i.e. rectangular boxes with forward-firing drivers. I’ll go even further: Even if the box is not rectangular but some incredibly fancy shape, even if it’s huge, even if it costs more than a luxury car, if it’s sealed or vented and the drivers are all in front, it’s a monkey coffin and will sound like a monkey coffin—boxy and, to varying degrees, not quite open and transparent."

 

[andreasmaaan]

Haha yes, I mean I'm aware of the standard criticisms of box speakers, all of which IMHO can be (but usually are not) addressed without getting rid of the box.

But I was curious as to what Aczel's specific criticisms were, and why he thought these were unable to be adequately addressed under any circumstances. All I can find on it from him is what @Swtoby quoted, which offers nothing by way of explanation.

 

[Swtoby]

Haha yes, I mean I'm aware of the standard criticisms of box speakers, all of which IMHO can be (but usually are not) addressed without getting rid of the box.

But I was curious as to what Aczel's specific criticisms were, and why he thought these were unable to be adequately addressed under any circumstances. All I can find on it from him is what @Swtoby quoted, which offers nothing by way of explanation.

To me he seemed to be saying the technology was just at its limit with that type of speaker. He really liked the Linkwitz Lab speaker and other manufacturers like Vandersteen are incorporating active bass management systems to help integrate better with the room. Stuff the "monkey coffin" will never do.

 

[mansr]

And are you the @mansr from CA forum? If so, warm welcome to the forum.

Yes, that's me.

 

[andreasmaaan]

To me he seemed to be saying the technology was just at its limit with that type of speaker. He really liked the Linkwitz Lab speaker and other manufacturers like Vandersteen are incorporating active bass management systems to help integrate better with the room. Stuff the "monkey coffin" will never do.

Ok, maybe. To me he seems to be specifically criticising box speakers though (at least, that's what I understand the standard definition of "monkey coffins" to be), regardless of questions of active vs passive, bass management etc. Hard to tell with the limited info...

 

[Blumlein 88]

Yes, that's me.

Glad to see you here mansr. Hope you'll be regular participant.

 

[Ayreonaut]

Linkwitz Lab:

In a reverberant room, the listener not only hears the direct sound but also the reflected sound, i.e. the off-axis radiated sound ... The speakers must be free from spurious resonant radiation and their off-axis radiation must follow their on-axis frequency response for the reverberant sound to be neutral. The polar radiation pattern must be essentially either omni-directional, cardioid or dipolar, aiming for constant directivity. The speakers must be acoustically small, yet capable of realistic volume levels at low non-linear distortion.

 

[oivavoi]

On box speakers, there are some potential sources for «boxiness» that I can think of:

Edge diffraction
Stored energy inside the box that has an unnatural decay
Uneven directivity with frequency

I don’t think any of these problems are insurmountable. Some of the best speakers I’ve heard have been boxes.

 

[svart-hvitt]

I am in agreement with what he says, except the bit about monkey coffins.

"In any case, one thing I am fairly sure of: No breakthrough in sound quality will be heard from “monkey coffins” (1970s trade lingo), i.e. rectangular boxes with forward-firing drivers. I’ll go even further: Even if the box is not rectangular but some incredibly fancy shape, even if it’s huge, even if it costs more than a luxury car, if it’s sealed or vented and the drivers are all in front, it’s a monkey coffin and will sound like a monkey coffin—boxy and, to varying degrees, not quite open and transparent."

Does this mean we need planar or open baffle speakers or does having a rear firing driver or two fix everything?

Take a look at this article by AES Fellow John Watkinson for a perspective:

https://www.thebroadcastbridge.com/...part-15-a-catalogue-of-shortcomings?cat_id=63

So I guess one can make a strong theoretical argument that the monkey coffin is not the perfect design.

 

[Purité Audio]

Yes, that's me.

Welcome Mans, I enjoyed the articles on your site.
Keith

 

[Ron Texas]

He hates monkey coffins because he didn't have any dead monkeys in the fridge.

 

[sergeauckland]

Take a look at this article by AES Fellow John Watkinson for a perspective:

https://www.thebroadcastbridge.com/...part-15-a-catalogue-of-shortcomings?cat_id=63

So I guess one can make a strong theoretical argument that the monkey coffin is not the perfect design.

I went to a couple of AES meetings at which John Watkinson demonstrated his Celtic Audio loudspeakers, including the strange Caber device. Interesting ideas, not without merit, but hardly mainstream.

S

 

[Sal1950]

Take a look at this article by AES Fellow John Watkinson for a perspective:
https://www.thebroadcastbridge.com/...part-15-a-catalogue-of-shortcomings?cat_id=63

Now here's a quote you can live by.
"Bad Speaker Design Is Seldom Lethal"

 

[svart-hvitt]

I went to a couple of AES meetings at which John Watkinson demonstrated his Celtic Audio loudspeakers, including the strange Caber device. Interesting ideas, not without merit, but hardly mainstream.

S

FWIW,

how did the speakers sound?

They’re on the smeller side, right?

And dispersion?

 

[Ron Texas]

Now here's a quote you can live by.
"Bad Speaker Design Is Seldom Lethal"

ROFLAMO.... How about a pair of those Magnepan room dividers?

 

[sergeauckland]

FWIW,

how did the speakers sound?

They’re on the smeller side, right?

And dispersion?

One pair were based on the Quad ESL63 with Celtic's add on stand/woofer/active crossover much like the Gradient sub in principle. It sounded pretty decent, in a fairly large meeting room. The caber was strange. Imagine a 15-20cm pipe, some 2m long, with a driver in each end, driven by an amplifier described as an analogue computer, and placed horizontally at ear height, like a monstrous sound bar. Within the limits of an AES meeting I really couldn't decide whether it was brilliant or not. Interesting design, but the meeting was more about design than performance.

S

 

[JJB70]

Peter Aczel could be quite provocative at times, which in fairness was one of the reasons his articles were so interesting. He was one of those writers who could make you question your own views and really think. On speakers, I tend to think he is correct in his prediction that we will see the end of the hi-fi amplifier and the dominance of active speakers. I tend to think we will see the digital speaker with wireless connectivity become dominant.

 

[mansr]

Now here's a quote you can live by.
"Bad Speaker Design Is Seldom Lethal"

Unless it's a high-voltage electrostatic thing gone wrong.

 

[melic]

Does anyone know what David Rich, the technical editor for The Audio Critic, is up to these days?

 

[Blumlein 88]

Unless it's a high-voltage electrostatic thing gone wrong.

Well there was that time working with high voltage on an ESL, I zapped a spark to my thumb. It hurt less than I expected. It did burn and cauterized a tiny hole in the skin of my thumb right down to the bone. If it had come from the panel there wouldn't have been enough current for that. But it was directly from the voltage doubler. Ouch!

Then there was the errant spark from a high voltage ignition system on a gas fired industrial boiler system I was trouble shooting. That one burned a similar hole in my palm, but felt like my whole arm/shoulder was paralyzed, fried and aching like I'd always imagined a phaser on stun would feel. I amended the troubleshooting procedure after that for our boilers. Oh and that was the problem. The step up transformer had come loose from the mount due to vibration and was letting voltage get places it wasn't supposed to be.