Cyclic debates and moderation

[Alan Sircom]

I agree. A dome tweeter with readily identifiable distortions that sit above levels identified by many well conducted studies as being audible is a different matter entirely to the differences between many (though not all*) capacitors which are orders of magnitude lower.

There are also many equally well-conducted studies that show those 'readily identifiable distortions' are well below the threshold of what we can perceive. Davis and Foster (1978) was effectively the 'move on' moment for the audio engineer when it was shown that significant differences in drive unit performance and even cabinet coloration could be effectively dialled out by EQ.

The problem is the assumption that because one branch of audio is less than perfect and therefore benefits from a subjectively based trial and error process, that all other areas deserve the same treatment.

This is special pleading. The trial and error process (which magically only appeared in your discussions today; prior to today it seemed to be just a numbers game) is not predicated on any objective requirement unique to loudspeakers. From a purely objective standing, we are all loopy audiophool nut-jobs for thinking there's a difference between a pair of good loudspeakers and a cheap soundbar, and daring to deploy some trial and error listening tests to justify that position.

If you've solved it, bag it and move onto the next problem because there are plenty of areas that would benefit.

Which is why there isn't much of what you or I might call 'audio' going on at the Audio Engineering Society these days. The loudspeaker is a fully resolved problem, just like everything else in the signal chain we use. The solution to that problem is achievable without the need for trial and error and the trial and error process is simply audiophool OCD, inventing solutions for problems that do not exist. It's why I likened the difference in capacitors (a relatively uncontentious piece of 'foo' for the objectivists in the room) to the difference in tweeters (which is claimed to make a difference by the same, but even that difference is contentious by those who take a more rigid view of objectivity in audio).

 

[Cereal Killer]

I think its about time for a milk break and some group hugging.

 

[Alan Sircom]

Before I form an opinion on that, I would like to see the numbers, both on the loudspeaker with the different tweeters and the amplifier with the different capacitors. I would expect, (but would be interested to be proved wrong) that there was rather more difference changing the tweeters than changing the capacitors.

S.

You miss my point. The engineering argument justifying PTFE caps is built on their better dielectric absorption properties, compared to electrolytics or polyprops. Electronics engineers outside of the audio world would dismiss this as vastly over-engineering the project because polyprop caps are good enough for the task in hand, and our hearing mechanism is not refined enough to hear the difference between the two types of cap. The same has been said for swapping out one tweeter with another; it's over-engineering and our hearing is not refined enough to hear the difference.

 

[Alan Sircom]

I think its about time for a milk break and some group hugging.

I came here to drink milk and kick ass. And I just finished my milk!

 

[Cereal Killer]

Cool. Kick away It's refreshing an'it.

I made some Main cables t'other day. Sounds better IMO. Just changed the isolation pads between the speakers and stands too....So that's new;
Balanced XLR's with Neutrik Gold's & Sommer carbokab-225, BKS 1.5mm 3 core with schurter 15A IEC's and HQ mains plugs, and new pads. Didn't cost much and i like the none measurable difference.

 

[Fox]

I came here for ass

and some big speakers

 

[Cereal Killer]

Is that whats known as a bootie call?

 

[Tenson]

There are also many equally well-conducted studies that show those 'readily identifiable distortions' are well below the threshold of what we can perceive. Davis and Foster (1978) was effectively the 'move on' moment for the audio engineer when it was shown that significant differences in drive unit performance and even cabinet coloration could be effectively dialled out by EQ.

There is a lot to be said for that, actually. FR and resonances are often linked, so if you fix one you fix the other. However, that doesn't touch on non-linear distortions, nor dispersion.

If we go by the old <0.1% THD is inaudible, then the distortion of most tweeters is audible, although subtle. Dispersion is still considered important among every bit of writing I have seen; we have yet to reach the ideal.

 

[Cereal Killer]

There is a lot to be said for that, actually. FR and resonances are often linked, so if you fix one you fix the other. However, that doesn't touch on non-linear distortions, nor dispersion.

If we go by the old <0.1% THD is inaudible, then the distortion of most tweeters is audible, although subtle. Dispersion is still considered important among every bit of writing I have seen; we have yet to reach the ideal.

Bingo!

 

[Paul R]

From a purely objective standing, we are all loopy audiophool nut-jobs for thinking there's a difference between a pair of good loudspeakers and a cheap soundbar, and daring to deploy some trial and error listening tests to justify that position.

I've obviously missed something somewhere.

Paul

 

[sergeauckland]

You miss my point. The engineering argument justifying PTFE caps is built on their better dielectric absorption properties, compared to electrolytics or polyprops. Electronics engineers outside of the audio world would dismiss this as vastly over-engineering the project because polyprop caps are good enough for the task in hand, and our hearing mechanism is not refined enough to hear the difference between the two types of cap. The same has been said for swapping out one tweeter with another; it's over-engineering and our hearing is not refined enough to hear the difference.

I think this is where we disagree. Swapping out the capacitors, even if it makes a measureable difference (which I doubt) will be unlikely to make any sort of audible difference. Swapping out the tweeters will most probably make an audible difference because, even if the frequency response remains identical (which clearly it won't do), even if the distortion parameters are identical, there's still the issue of dispersion and therefore the in-room result will be different. Listening to the two systems in an anechoic chamber, if the frequency response and distortion characteristics are identical, then probably would not sound different, but in a room, with different absorbtions in different directions, the dispertion characteristics will create a different sound-field.

S.

 

[Robert]

This is special pleading. The trial and error process (which magically only appeared in your discussions today; prior to today it seemed to be just a numbers game) is not predicated on any objective requirement unique to loudspeakers. From a purely objective standing, we are all loopy audiophool nut-jobs for thinking there's a difference between a pair of good loudspeakers and a cheap soundbar, and daring to deploy some trial and error listening tests to justify that position.

Not at all. The process chosen to assess depends on the level of understanding and the magnitude of the differences under investigation. What's 'loopy' is thinking you should adopt a one policy fits all attitude because it completely disregards the fact that progress and understanding isn't uniform across all aspects of audio.

There is no mystery in seeing no mention of trial and error.
These discussions are invariably around electronics and cables, if you ask me about the electromechanical elements within the chain you'll get a different answer, as you have.
That's mostly because the subjective 'I like or I dislike' response is more common for those parts of the chain.

 

[Alan Sircom]

Not at all. The process chosen to assess depends on the level of understanding and the magnitude of the differences under investigation. What's 'loopy' is thinking you should adopt a one policy fits all attitude because it completely disregards the fact that progress and understanding isn't uniform across all aspects of audio.

There is no mystery in seeing no mention of trial and error.
These discussions are invariably around electronics and cables, if you ask me about the electromechanical elements within the chain you'll get a different answer, as you have.
That's mostly because the subjective 'I like or I dislike' response is more common for those parts of the chain.

But if the difference between device A and device B is in the same order of magnitude as the difference between device C and device D, shouldn't you evaluate them on a level playing field?

The fact that A and B might be loudspeakers and C and D are amplifiers is immaterial if it all takes place behind the curtain.

I've performed tests of amplifiers blind and tests of loudspeakers blind. Unless you stack either deck (say throwing the odd SET amp into the mix, or evaluating full-range behemoths next to bookshelves that start rolling off at 100Hz) the differences are in the same ball-park magnitude.

Ultimately, it's that crucible of blind testing that convinced me that either the differences between electronics are larger than the nay-sayers claim they are, or the differences between loudspeakers are smaller.

 

[Alan Sircom]

I think this is where we disagree. Swapping out the capacitors, even if it makes a measureable difference (which I doubt) will be unlikely to make any sort of audible difference. Swapping out the tweeters will most probably make an audible difference because, even if the frequency response remains identical (which clearly it won't do), even if the distortion parameters are identical, there's still the issue of dispersion and therefore the in-room result will be different. Listening to the two systems in an anechoic chamber, if the frequency response and distortion characteristics are identical, then probably would not sound different, but in a room, with different absorbtions in different directions, the dispertion characteristics will create a different sound-field.

S.

The dispersion characteristics of a ribbon tweeter and a dome will be very different, which will create a distinctly different sonic presentation. And I forgot the Audiosmile now has a ribbon tweeter, in fairness. But the dispersion characteristics of two fabric dome tweeters, from a measured perspective, are often 'good enough for government work'. They wouldn't necessarily be interchangeable, but if you crank up the Discriminator 5000 Blindtestatron to the point where you can't hear differences in amplifier performance, these speaker difference might be too subtle, too.

 

[Alan Sircom]

I've obviously missed something somewhere.

Paul

Hey, I'm an audio journalist. I get paid to exaggerate. I must have told you that like a billion times.

 

[Tenson]

The dispersion characteristics of a ribbon tweeter and a dome will be very different, which will create a distinctly different sonic presentation. And I forgot the Audiosmile now has a ribbon tweeter, in fairness.

It's had one since the beginning. Only a single prototype pair was ever made with a dome, and never seen by the public.

 

[Alan Sircom]

It's had one since the beginning. Only a single prototype pair was ever made with a dome, and never seen by the public.

Sorry, my bad. In fairness, I do see a lot of speakers.

 

[Cereal Killer]

Simon, It doesn't matter if you made 1 or 1000; the point is, after designing the speaker you changed it because you didn't like the way it sounded, not because the spec wasn't good enough but your subjective instinct told you it wasn't good enough.

 

[sergeauckland]

The dispersion characteristics of a ribbon tweeter and a dome will be very different, which will create a distinctly different sonic presentation. And I forgot the Audiosmile now has a ribbon tweeter, in fairness. But the dispersion characteristics of two fabric dome tweeters, from a measured perspective, are often 'good enough for government work'. They wouldn't necessarily be interchangeable, but if you crank up the Discriminator 5000 Blindtestatron to the point where you can't hear differences in amplifier performance, these speaker difference might be too subtle, too.

Agreed. The differences I was referring to was indeed between a dome and a ribbon.

I also agree that the differences between comparable loudspeakers, whilst greater than that between comparable amplifiers, are smaller than many would have one believe. Whilst I don't think that two different loudspeakers would pass an AB test, an ABX test might be more difficult.

I wonder whether this convergence of performance is in any way responsible for some new loudspeaker designs deviating from the desideratum of a flat frequency reponse far more than would seem to be accidental. The rise at HF seen with some of today's designs, compared with the flat, or slightly drooping HF response of a few years ago might be a way of making purchasers "listen to all that detail".

In the way that the valve revival could be seen as a reaction to "all SS amps sound the same", I wonder if that sort of thing is now going on with some loudspeaker manufacturers who might struggle otherwise to persuade purchasers there's a reason to change their 'speakers.

S.

 

[john dolan]

I think the valve revival was more to do with CD sounding cold and sterile compared to records.