Untill it glue the coil in the gap ;-)A little ferro-fluid would take care of that problem
kgrlee;3275361I said:It's sad that so few people bother to conduct Listening Tests properly. 😡
Indeed - the first error they make is calling it, and treating it as, a 'test' when listening is purely for pleasure. Of course its not actually 'sad' rather ignorant, and as Ricardo remarked 'profits are made from differential stupidity'.
JC, continually baits us with statements likeOr are you baiting John again. He already said no to any testing of his personal equipment. Just wondering.
Also his pontificating on how important certain tests are but there is no need to conduct these on his own designs.I am constantly confronted by my critics that this is 'reality' and that my 'extreme' efforts are just a waste of time, but I haven't gotten any takers as of yet.
But Christophe, Jay, Frank, your good self and many others have brought up important points on the conduct of Listening Tests which would be useful to summarize in the context of Blowtorch.
FWIW, it's likely many of JC's designs would come up with a NULL result when compared with an evil 4558 design, even in the most carefully conducted and stress free Blind Listening Test. 😡
But Blowtorch is of such unique quality that I really believe it will NOT produce a NULL result but show significant differences in a Blind Listening Test that would be picked up by very good listeners. 🙂
My hope is that this (sadly hypothetical) test will reveal these differences clearly and that the results will also be beyond criticism by everyone. Surely this will further enhance JC's exalted reputation? 😉
I WANT a positive result in a test of Blowtorch and for this, I will do my best to get the very best ears on this, hence my choice of John Atkinson. If some trans Atlantic/Pacific travel is possible, we may be able to bring 5 of the very best ears to this test instead of just 2. plis xskus mi rithmetik.
There is absolutely no intent to denigrate or show up JC's ancient ears. Being old myself, I am well aware of the problems. Instead, I have several times urged him to suggest true golden pinnae among his friends to take part. They may be even more discriminating than my 5 especially when listening out for the merits of Blowtorch.
What we would appreciate from JC, is some help to make sure Blowtorch is performing at its best; ancillaries, cables, room etc.
If he just lent us his spare Blowtorch, we would still miss his expertise in the above. Perhaps he could nominate someone who's competence he trusted.
kgrlee,
Why not just get the schematic and build a copy and then test it. You would have to make a perfect copy though and use virgin aluminum for the chassis.......🙄
Why not just get the schematic and build a copy and then test it. You would have to make a perfect copy though and use virgin aluminum for the chassis.......🙄

I love the term, "Rub & Buzz distortion" ... one of the cheap speakers in my system actually suffers from this when cold, at one stage I was fooling around a bit with the MATT track for assessing speakers and this made it obvious. The interesting thing is that driving the speaker hard effectively "lubricates" the problem area, you can hear this distortion steadily disappearing as the suspension or whatever warms up.
I wonder whether other speaker drivers behave the same way ...??
Frank
All of them exhibit usually undefined artefacts.
One of my best experiments:
Take any driver .......
In a quiet room lay it on the table in front
of you.
Drive it to just less than xmax @ ~ 10Hz
Listen carefully ..........
What we would appreciate from JC, is some help to make sure Blowtorch is performing at its best; ancillaries, cables, room etc.
Don't you have to pick a decent source first? What's it to be - vinyl, tape or DAC or all of the above?
how could vinyl or tape be on any list of "technically decent" source? - or even "audibly transparent" - both vinyl and tape have clearly audible defects in addition to the numbers
But ... have you tried doing that with the driver dead cold, and then compared that to the same unit after it's been installed in a carcase and driven hard for an hour or so with real music material, removed immediately and laid on the table again ...?All of them exhibit usually undefined artefacts.
One of my best experiments:
Take any driver .......
In a quiet room lay it on the table in front
of you.
Drive it to just less than xmax @ ~ 10Hz
Listen carefully ..........
Frank
You forgot cassette tape on your list.......
Because I was only talking about decent sources Steven 🙂 That one's neither decent nor technically decent.
😀 You could have faked a troll by interpreting 'tape' as 'cassette tape' rather as jcx interpreted my word 'decent' 😉
Frank, if it's a small speaker, get a pack of Cotton Wool from the chemist and try wedging a lump behind the cone and the chassis. Try not to move the cone forward or backward.... one of the cheap speakers in my system actually suffers from this when cold, at one stage I was fooling around a bit with the MATT track for assessing speakers and this made it obvious. The interesting thing is that driving the speaker hard effectively "lubricates" the problem area, you can hear this distortion steadily disappearing as the suspension or whatever warms up.
It's not a permanent solution cos the Cotton Wool eventually falls off.
If you play a sine wave while pressing gently on the cone surround, you can work out which way you need to nudge the cone.
On a big speaker, turning the unit round often works. What happens is that heat/humidity allows the cone/coil assembly to creep and tilt.
I know all this cos that's how I get the computer speakers I rescued from the tip to work.
both vinyl and tape have clearly audible defects in addition to the numbers
Not disputing that for a moment. Current digital implementations have clearly audible defects IME too even though standardized numbers don't as yet exist for them. But I have no doubt they'll come in due course.
One of the most important facets of the test is that the subject picks the music and the source.Don't you have to pick a decent source first? What's it to be - vinyl, tape or DAC or all of the above?
If JC, was doing the test, he uses his own CDs, vinyl, SACD etc. And he MUST be happy with the player; .. not a problem if the test is conducted at chez Curl.
But if his nominated golden pinnae wants cassettes, presumably this august person has a good cassette player he could lend us. Alas, all of mine are dead even if the termites haven't eaten them.
Abra, this is another important facet; that the subject 'enjoy' at least one presentation.Indeed - the first error they make is calling it, and treating it as, a 'test' when listening is purely for pleasure.
We ensure this by letting the subject listen to his preferred system while he can see what it is first so he is happy it is functioning correctly.
There is no doubt in my mind that Blind Tests are stressful. IMHO, this is the MOST important criticism of most Blind Tests. I spent nearly 2 decades working on this problem with some success.
It's only when you manage this that you have any chance of finding the true golden pinnae. If you are lucky enough to find them, be prepared to be amazed at what some people can pick out.
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OK, sounds a tad more promising than the usual tests 🙂 I guess that could be because you're not (as in the case normally) expecting a null result?
Is anyone seriously interested in yet another NULL test result? At best, it would rate a single line in a Stereophile editorial. Certainly not worth an AES paper from the Dynamic Duo.OK, sounds a tad more promising than the usual tests 🙂 I guess that could be because you're not (as in the case normally) expecting a null result?
But if some people can reliably distinguish between Blowtorch and an evil 4558 device, this would be NEWS. It would answer Jay's Question 1.
Only if the answer to this is YES, can we answer his Question 2 Which one sounds better?
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