The Audiophoolery Thread.

[The General]

In my day job I work in the R&D facility of one of the major motor manufacturers. One of my responsibilities is audio sound quality & we carry out subjective listening tests on prototype vehicles. All our listeners have an engineering background (as do I) & we generally get pretty consistent results despite us all liking different music genres (for the record, I like rock & 50s). None of us subscribe to the audiophoolery snake oil theories.
I was Googling some info & found a link to this website: http://wathifi.com/ a collection of pseudoscience from audiophile mags. Worth looking at for a chuckle, it amused me for a half hour or so.
I liked the comment stating that double blind tests may be OK for pharmaceutical companies, but had no relevance for hifi....
One link also said that A/B/X tests were meaningless, because when you do them, 'all amplifiers sound the same'
Enjoy....
Mark

Much cheaper than fancy wires even if you do feel like muck in the morning.

The secret is to stay drunk!

[mark_in_manc]

Just thought I'd mention that a few years ago Bech and Zacharov was a good text for getting into psychoacoustic testing, and Roederer was a good intro to psychoacoustics in general.

I had a few students do ABX projects in an IEC-spec listening room on fancy speaker cable vs long lengths of bell wire, sometimes left on the reel! They used reasonably-sized (and sometimes audiologically-screened) test panels, and messed around with all sorts of fancy stats, ANOVA etc etc. No-one ever showed a repeatable difference (let alone preference) once the extraneous variables were controlled. But you knew all that - this is one of those 'science has shown us the obvious' stories. Luckily it was student work, and no-one had defrauded the EPSRC over it.

[Cobaltblue]

I did all my Phoolery almost 40 years ago turns out what I was really interested in all along was content.

Didn't matter if the quality wasn't perfect turns out the music was what I enjoyed.

I often listen to content on youtube through tinny PC speakers the Radfords Quad etc all idle, I dont even have a decent system in my flat during the week.

Does it diminish my enjoyment for something that takes my fancy at that moment not a bit of it

Don't laugh last night I was listening to Slade, I dont suppose that was ever produced with HiFi in mind, and I enjoyed it with a total lack of Fi.

Mama weer all crazee now

Back in the late 70's I was listening to this on a system that cost me well over £1000 even then. I dont remember enjoying at any more than I did last night but the memory dims.

Cheers

Mike T

[Radio Wrangler]

I someone comes up to me and says "I like the xxxxx phono cables and use them everywhere because they are well made, won't fall apart, have a nice finish, won't corrode, and are made from materials I feel are special", well I'll probably agree with them. Said cables could possibly start their car (or tow it) and be somewhat overkill, but that's not a problem in itself. I'd get worried if he was living off only baked beans in order to pay for them.

If someone comes up to me and says "I use xxxxxx phono cables because I can hear a difference. It's small, but it's there." Then I'll wonder if there is a real difference. Maybe it's illusory and he hasn't tested in a way which neutralises wishful thinking. Maybe it's real and I've missed something interesting. I don't worry whether or not he's been exploited, he's happy, just so long as he isn't having to live off only baked beans in order to pay for them.

If someone comes up to me and says "I use xxxxxx phono cables because I can hear a difference. It's awesome, I've listened to all my records and heard lots of things I never knew were there." This exceeds what I'm prepared to believe without very careful checking. The only way for this to be real is if whatever he compared them to were surprisingly bad. I strongly suspect he's been led up a garden path. My feelings are like those I felt on learning that a 98 year old neighbour gave her bank details to a nice cold-caller.

If someone comes up to me and says "I use xxxxxx phono cables....etc, etc because they use single-strand silver and that not only prevents sonic smearing caused by strands touching, it also avoids factorisation distortion - after all, 'There is no number more prime than one' " Then the gloves come off. This guy is infected with serious pseudoscience and total bull. He's not a victim, he's a carrier!

David

[Refugee]

Originally Posted by dseymo1

The tubes would have to be exactly the same length. Mercury delay lines are, I think, fairly well known. Any difference in the tubes would result in the signal to each speaker arriving out of phase with the other. But then what about the small but surely audible difference in timing between the axis and the radius of the mercury columns...

Would those cables not turn into a load of squashy poisonous ball bearings and roll away if they got damaged

[Refugee]

I have been wondering if anyone has thought of having a ferrous metal chassis close to the transformers making the amplifier sound magnetic?
Then you have the issue of cast or sheet non-ferrous metal?

[Radio Wrangler]

Mercury delay lines are well known, but are acoustic in operation. Electrical signals travel through the stuff at quite normal speeds.The difference might not be important in the logic of audiophoolery which would give even Velikovsky a run for his money.

David

[Farzooks]

I've always just used what speaker wire came to hand. Currently I'm working my way through a 100m drum of 2.5mm stranded I bought at least a decade ago. In the past I've used some fairly nondescript stuff and can honestly say I've had perfectly good results from 1.5mm T&E when I had to. That T&E installation lasted for years until I sold the house and I never felt the need to change it.
I noticed with some alarm yesterday my 100m reel is showing signs of depradation - why, it might only last another 15 years at this rate.

[Craig Sawyers]

The only thing that cables effectively do is manage RFI. Say what?

The problem is that we live in an increasingly RF polluted environment, from mobile phones to digital cordless phones, to LED lights, to ethernet over mains, to bluetooth etc etc.

The main effect on audio is that when high frequency RF gets into audio electronics, unpredictable effects can happen. I'm sure we've all heard our mobile doing a station seek, when the sound system goes zzt-zzt..... . That is high hundreds of MHz getting in and being rectified by junctions in your audio gear, mainly the preamp section. Even the BBC is not immune to this - I've certainly heard that when a guest has their phone on while being interviewed.

That these effects are real underlies the no-phones in aircraft and hospitals.

And if RF is picked up by your speaker cables, it gets into the feedback loop of the power amp with very unpredictable effects, dependent on the design of the amp.

Anyhow, my system is balanced in and out, with due consideration of the pin 1 problem. I use studio grade screened twisted pair cable from Canford Audio, which is about £1 per metre. I use Neutrik EMC series XLR's. My only audiofoolery is the speaker cables - for which I use Kimber. This is a woven construction, with very low inductance and very high capacitance - so it inherently acts like an RF filter - although another way of skinning the RF cat is just to use a Zobel at the speaker end.

Also mains cables need careful consideration to manage the junk that comes out our mains, particularly in these days of ethernet over mains. Once inside a chassis, that can radiate via anything that looks like an antenna. Mains filters a-la Shaffner are next to useless since they are only specced to operate up to 30MHz (or occasionally to 60MHz), and can often resonantly amplify interference at higher frequencies.

I believe that when listeners report different sound quality between cables, they are mainly hearing the difference in RF characteristics when linked up to their particular system, in their particular location.

Craig

[GrimJosef]

Do you know of a link to any hard numbers on this Craig ? I would guess that signals from a mobile phone are, by some way, the strongest free-space RF fields that audio equipment is ever exposed to. Perhaps the radio signals from passing taxis/emergency services come next (obviously very dependent on how close the nearest road is) ? Then Bluetooth and domestic wi-fi ? Then, considerably further down, the broadcast stations ?

Cheers,

GJ

[Valvepower]

Hello,

Current production hi-fi equipment should comply with the EMC susceptibility limits as set out in BS EN 55020. This includes conducted immunity of the all connected audio and mains leads. I’ve had instances where a unit suffered susceptibility and emission issues during EMC testing and when a modified and compliant unit was subsequently listened to by those who ‘listen’ it was said to have improved the sound

Please, please can I tactfully and politely point out that not all people who work in the hi-fi and audio industry are audiophools – some are cracking engineers doing their job in manufacturing, during these challenging times for British manufacturing.

Regards
Terry

[Craig Sawyers]

It is on my measurement bucket list; I have the kit to do it - a 7L5 and 7L12 spectrum analyzers and current probes to 1GHz.

[Craig Sawyers]

Originally Posted by Valvepower

Current production hi-fi equipment should comply with the EMC susceptibility limits as set out in BS EN 55020. This includes conducted immunity of the all connected audio and mains leads. I’ve had instances where a unit suffered susceptibility and emission issues during EMC testing and when a modified and compliant unit was subsequently listened to by those who ‘listen’ it was said to have improved the sound

Please, please can I tactfully and politely point out that not all people who work in the hi-fi and audio industry are audiophools – some are cracking engineers doing their job in manufacturing, during these challenging times for British manufacturing.

I totally and utterly agree with all that.

But alas not all audio gear, including professional audio, has had EMC susceptibility even considered. I think your word "should" suggests that might be the case.

[stevehertz]

Originally Posted by Ilikevalvesme

In my day job I work in the R&D facility of one of the major motor manufacturers. One of my responsibilities is audio sound quality & we carry out subjective listening tests on prototype vehicles. All our listeners have an engineering background (as do I) & we generally get pretty consistent results despite us all liking different music genres (for the record, I like rock & 50s). None of us subscribe to the audiophoolery snake oil theories.
I was Googling some info & found a link to this website: http://wathifi.com/ a collection of pseudoscience from audiophile mags. Worth looking at for a chuckle, it amused me for a half hour or so.
I liked the comment stating that double blind tests may be OK for pharmaceutical companies, but had no relevance for hifi....
One link also said that A/B/X tests were meaningless, because when you do them, 'all amplifiers sound the same'

Mark, it's always a joy to read a post from someone - with professional audio experience - whose feet are firmly on the ground, and to some extent whose tongue is firmly in their cheek. I too had to 'lol' when I read that last sentence! You just couldn't make it up could you?!!! No, for sure, ABX testing puts the fear of death into most audiophools. It's akin to holding up a cross or garlic to a vampire.

I've been to many an audiophool's house and listened to their XX thousand pound systems. And you know what? I haven't heard a good one yet, or one that would approach what you could (intelligently and with good 'audio knowledgeable' ears) put together for less than a grand. And the reason in most cases is that they are using esoteric speakers that cost a fortune and are designed and made by some bloke out in the desert in California or Spain who eschews accepted speaker theory and practise. Such speakers are usually along the lines of multiple, unmatched drive units and highly polished, exotic wood, odd shaped cabinets. But the hifi mags rate them very highly. Yeah, so they must be great.. You can always tell an audiophool on a forum by looking at their avatar where their hfi set up is listed. It's usually a collection of weird names (cottage industry one man bands normally) that are hard to pronounce, extremely expensive and very 'prestigious' to those in the know.

[stevehertz]

Originally Posted by Craig Sawyers

The only thing that cables effectively do is manage RFI. Say what?

The problem is that we live in an increasingly RF polluted environment, from mobile phones to digital cordless phones, to LED lights, to ethernet over mains, to bluetooth etc etc.

The main effect on audio is that when high frequency RF gets into audio electronics, unpredictable effects can happen. I'm sure we've all heard our mobile doing a station seek, when the sound system goes zzt-zzt..... . That is high hundreds of MHz getting in and being rectified by junctions in your audio gear, mainly the preamp section. Even the BBC is not immune to this - I've certainly heard that when a guest has their phone on while being interviewed.

That these effects are real underlies the no-phones in aircraft and hospitals.

And if RF is picked up by your speaker cables, it gets into the feedback loop of the power amp with very unpredictable effects, dependent on the design of the amp.

Anyhow, my system is balanced in and out, with due consideration of the pin 1 problem. I use studio grade screened twisted pair cable from Canford Audio, which is about £1 per metre. I use Neutrik EMC series XLR's. My only audiofoolery is the speaker cables - for which I use Kimber. This is a woven construction, with very low inductance and very high capacitance - so it inherently acts like an RF filter - although another way of skinning the RF cat is just to use a Zobel at the speaker end.

Also mains cables need careful consideration to manage the junk that comes out our mains, particularly in these days of ethernet over mains. Once inside a chassis, that can radiate via anything that looks like an antenna. Mains filters a-la Shaffner are next to useless since they are only specced to operate up to 30MHz (or occasionally to 60MHz), and can often resonantly amplify interference at higher frequencies.

I believe that when listeners report different sound quality between cables, they are mainly hearing the difference in RF characteristics when linked up to their particular system, in their particular location.

Hmm, interesting stuff Craig, I've learned from that. Just one point, wrt your very high capacitance speaker cables, how does that work when you are effectively putting that 'very high capacitor' in parallel with the speakers' crossover unit? it must screw things up terribly surely? In particular, a reduction of the high frequency content of the audio signal reaching the speaker/crossover.

Also, you mention that mains cables need careful consideration but you do not provide an answer as to what you think does work/is good, only what won't work. Thanks.

[Craig Sawyers]

When I was in charge of Wharfedale's R&D and product development, we most definitely used ABX. Speakers behind an acoustic curtain the entire width of the listening room. You had no idea what was behind there. You just had a switch box and a sheet to write your comments. It was always fascinating to find out what my devious team had put behind the curtain! Actually in practice it was often used to optimise crossovers and cabinet construction details. Almost always a mono test to prevent confusion with listening to stereo.

An ABX test, I have to say is very difficult to do in practice as a test subject!

Regarding speakers, I use the LX521, designed by the ex-Hewlett Packard spectrum analyzer developer Siegfried Linkwitz. Based on hard technology http://www.linkwitzlab.com/ .

Craig

[Radio Wrangler]

Originally Posted by Craig Sawyers

speaker cables - for which I use Kimber. This is a woven construction, with very low inductance and very high capacitance - so it inherently acts like an RF filter - although another way of skinning the RF cat is just to use a Zobel at the speaker end.

We don't often disagree, Craig, but I think you've missed something.

The full Zobel network on the output of an amplifier consists of two sections. One is a series R-C pair which shunt the output of the amplifier. Together these provide a nice, resistive load to the amplifier at frequencies above audio, without burdening it significantly in the audio range. This is nice but isn't terribly important with well designed amplifiers.

The second part of the full Zobel network is a parallel indictor-resistor in series with the output (after the Zobel shunt). The job of this part is to prevent capacitive loads (exactly like those woven speaker cables) from creating excess phase shift in the feedback loop by the load capacitance and the output impedance of the output transistors creating an additional pole in the loop. The amplifier is isolated at RF from the cable/crossover capacitance and it sees the series resistor instead. This takes the cable/crossover C out of the loop.

Some high faluting amps of the nineteen eighties eschewed the series path Zobel network (presumably on religious grounds) and were renowned for taking off at RF when confronted with high-C interwoven cables. Smoke and large bills followed.

So high-C speaker cable isn't an alternative to the full Zobel, it is something which needs the full Zobel.

The business of running feedback amplifiers and feedback controlled voltage regulators into capacitive loads is a classic problem in design. The maths of loop stability scare a lot of people, but the problem is real.

David

[Craig Sawyers]

Originally Posted by stevehertz

Hmm, interesting stuff Craig, I've learned from that. Just one point, wrt your very high capacitance speaker cables, how does that work when you are effectively putting that 'very high capacitor' in parallel with the speakers' crossover unit? it must screw things up terribly surely? In particular, a reduction of the high frequency content of the audio signal reaching the speaker/crossover.

Also, you mention that mains cables need careful consideration but you do not provide an answer as to what you think does work/is good, only what won't work. Thanks.

Speaker cables of such construction are a double edged sword, because some amplifiers object to an almost perfectly capacitive loading. Typically 500pF/m but only 100nH/m inductance..

But it does not impact the crossover at all provided the amplifier is unconditionally stable.

I specifically did not mention mains cable types; I have to declare an interest, since a range of EMC attenuating cables of my design is on the market on a royalty basis for prices that would make your eyes water.

I hesitate to mention a good alternative that sounds great, but is dirt cheap. I did on another forum and was excoriated so completely and repeatedly on the basis of safety that I quit the forum. So I remain stum on that - sorry.

[stevehertz]

Understood. So, put another way, in looking out for such a unit, what kind of specs should one be looking out for; what are the essential features (and figures) to look for?