empirically i must agree: musical enclosures outside paradign of most engineers

Daygloworange · « **Reply #40 on:** 3 Jul 2007, 12:36 pm »

Quote

I do agree with your two examples , my point of view still holds, so what is your point?

I feel that I made my point already.

Cheers

1000a · « **Reply #41 on:** 3 Jul 2007, 07:39 pm »

I have absolutley nothing to post to the thread at this time, but I am totally captivated and learning new things by leaps and bounds. Andy the signal wire sizes inside the gear was especially insightful. Please keep this one rocking.

Builder Brad · « **Reply #42 on:** 4 Jul 2007, 04:43 pm »

very interesting thread.

Gave me a reason to improve the way I mounted the main pcb in my GK 1R. I was never happy with the way it was fitted into my aluminum case - the pcb was floating, and this could not have helped the performance in any way, so I have now made 2 substantial blocks from some scrap walnut I had lying around and have securely fitted these to the chassis which then holds the pcb in place with some insulated stand offs.

My only problem with this is that the 2 tubes are now in contact with part of the walnut blocks - does this present any fire risks? I am trying to minimise my carbon footprint!

Brad

kyrill · « **Reply #43 on:** 4 Jul 2007, 07:13 pm »

i would chip or mill a bit from the wood to make room for the tube and in the beginning you will smell roasted walnut, but fear not to handle that see:
Chilli Chicken Wings with Roasted Walnut and Anchovy Salad http://www.abc.net.au/brisbane/stories/s269619.htm

the air heated between tube and wood can "escape" i presume

doug s. · « **Reply #44 on:** 5 Jul 2007, 12:28 am »

alfa romeo, eh? alfas have been my daily drivers for fifteen years, now. they ARE better!

doug s.

Quote from: Seano on 2 Jul 2007, 10:19 pm

Kyrill, without putting words into Jules' mouth I suspect we were both thinking much the same thing.

A wooden doesn't necessarily sound better than a metal box. It just sounds different.

'Better' is a value judgement. It's subjective. Jules' comment re beauty has it nailed - if it looks better then it must be better. This is something we all understand isn't always true but we are all victims regardless (Alfa Romeo comes to mind for some reason ).

'Different' is my attempt at an objective judgement.

kyrill · « **Reply #45 on:** 5 Jul 2007, 08:23 am »

i still drive my beloved 164 v6 form 1990, only standard garage checks

Seano · « **Reply #46 on:** 5 Jul 2007, 11:41 pm »

:lol:don't for a moment think that I'm not a fan of Alfa Romeo....they've flitted in and out of my life before......it's just that sometimes they are a prime example of beauty over quality & function.

...but I'd still like a Brera for Xmas.

AKSA · « **Reply #47 on:** 6 Jul 2007, 12:14 am »

A good friend is a highly trained mechanic, and works exclusively on prestige cars.

He told me recently of a V6 Alfa motor he worked on. The cylinder head studs are strain torque bolts; you set them at around 40Nm then turn them a number of degrees on from this point to set up a strain base entirely on thread pitch.

The twist is, IIRC, TWO FULL TURNS!! Manny told me he thought the bolts would break off, or fracture in the block..... this 1 helluva setting!! My old Toyota MX83 is only 80Nm in total; a very low stressed fitting.

I'm told the Alfa V6 is one of the most exhilirating motors to drive that's ever been built.... but there are some question marks over its longevity. In my experience even a firecracker motor like a BMW will last very well if the oil is changed every 5000 kms and it's warmed up carefully from cold.

The Toyota 2JZ inline 6 is how being used in the US turbocharged to 40psi for Pro Stock Drag racing, and has seen 1700 bhp - not bad for three litres!! Wonder if the Alfa could beat that?

Cheers,

Hugh

kyrill · « **Reply #48 on:** 15 Jul 2007, 11:07 am »

quote Yves Bernard Andre, the designer of YBA amplifiers, told me and a friend 14 years ago (as retailers of his product) that his amps sounded better with the tops off and even better with all casework gone - the only reason he had metal casework was the market demanded it and he felt he would go out of business if he went that far!

Denis Moorecroft (DNM) is about the only other manufacturer that comes to mind who consciously avoids metal casework.

I think the subject needs re-examining.
unquote http://www.audiocircle.com/index.php?topic=36765.20

andyr · « **Reply #49 on:** 15 Jul 2007, 11:11 am »

Quote from: kyrill on 15 Jul 2007, 11:07 am

quote Yves Bernard Andre, the designer of YBA amplifiers, told me and a friend 14 years ago (as retailers of his product) that his amps sounded better with the tops off and even better with all casework gone - the only reason he had metal casework was the market demanded it and he felt he would go out of business if he went that far!

Denis Moorecroft (DNM) is about the only other manufacturer that comes to mind who consciously avoids metal casework.

I think the subject needs re-examining.
unquote http://www.audiocircle.com/index.php?topic=36765.20

And yet I just read an article on the Stereophile website than Ken Shindo makes all his amp cases out of steel as he doesn't like the sound of aluminium!

Regards,

Andy

kyrill · « **Reply #50 on:** 15 Jul 2007, 11:17 am »

hi Andyr

well steel sounds better than alu
alu must be one of the worst sounding objects
but he must have commercial market after thoughts as well

coz many things sound enormously better than steel

kyrill · « **Reply #51 on:** 4 Nov 2007, 11:50 am »

hi
found some nice photoos of what i consider as one of the masters of present audio development:

"For his own use, Salabert uses stripped-down electronics in wooden casings where capacitors are denuded and as many synthetics removed as practically feasible. While of modest origins, these modifications rather elevate the gear's performance beyond original sales costs."

Bernard's CD player in a box

Bernard Salabert is designer and producer of PHY speakers
http://www.phy-hp.com/English/Products/Products.html

i was reading a bit an review and stumbled on this:

".... All we had to do was unscrew the bottom plates and take out two jumpers per amplifier. That remedied the auto reset protection. Ten minutes later, the amps were playing upside down without bottoms for easy access just in case. Gone was the problem but there was something else. The sound has changed into a just slightly rounder version of the sound before the miniature surgery. We closed up the aluminum boxes again and proceeded to listen. Again something had changed. The roundness was gone again. A little gentle bite was reintroduced, acoustic guitars seemed to be played with a harder nail or pic, violins bowed more on the bow's edge. Was it the amplifier's chassis?
We removed the bottom plate again. Back was that roundness. In the end, we left a few screws out from the bottom and got what to our ears was the best sound.
Is it the enclosure that has so much influence? It must be. Other Class D amplifiers we heard had some zing in their sound, a metallic edge. Few sounded different in a positive way, most notably the Red Dragon Leviathan. Is it the latter's wooden chassis that exerts such a positive influence? Now that we thought about it, the big brother of the MP150, the MP350, does have a lot of wood covering its electronic innards. An interesting test would be to wrap a Trends Audio Class D miniature amp in wood."
fromhttp://6moons.com/audioreviews/kharma2/matrix.html

photoos from
http://6moons.com/industryfeatures/phy/phy.html

Srajan Ebaen · « **Reply #52 on:** 4 Nov 2007, 03:20 pm »

Eduardo de Lima of Audiopax compared his original Model 88 amp inside aluminum, steel and brass enclosures. Brass won even though applying ripple-less chrome to it proved a royal pain in the arse. So brass it was. He had no good scientific reason (and this is a very humble designer who very clearly distinguishes between what he knows and doesn't) but his ears plainly told him and he followed suit even though it was not the practical thing to do.

Another manufacturer with advanced know-how in composites already has done such experiments years ago where he took a stock CD or amp circuit from a good make, say Arcam level, discarded the stock bent sheet metal casing and stuck the innards into various enclosures made from non-traditional materials, including some which allowed organic rather than rectangular forms.

His assessment? HUGE differences. If I understood him correctly, he felt the primary reason had to do with resonant behavior down to the circuit level.

Many Japanese underground designers for years have advocated wooden platforms, wooden enclosures. Yamamoto sticks his custom capacitor inside an ebony sleeve rather than plastic. Duelund does the same for caps and resistors. Then there's the whole MDI/triboelectric effects angle which apparently looks at synthetic materials as culprits for ultrasonic micro discharges which are avoided when using organic materials (say silk, paper, cotton for cable dielectrics).

From what I've seen and heard, there seems to be a huge segment still barely tapped by the mainstream commercial sector. It could be a combination of resonant and "micro-electrical" behavior. There are circuit designers who believe that "electroncs don't like sharp corners" and accordingly lay out their traces such as to make organic bends rather than right angles...

Kevin Haskins · « **Reply #53 on:** 4 Nov 2007, 04:21 pm »

I prefer Legos and Silly Puddy. Their modular construction allows easy modification. Silly Puddy has great dampening properties and you can always make bouncy balls with it too.

AKSA · « **Reply #54 on:** 4 Nov 2007, 08:55 pm »

Ah, yes,

Golden ears v. EEs. Always a feisty debate!

For myself, fence sitting has given me huge discomfort over the years......

Hugh

Srajan Ebaen · « **Reply #55 on:** 5 Nov 2007, 05:41 am »

What Kevin's gentle ridicule and your comment perhaps overlook is that those who have and continue to experiment with the effects of enclosure and cable materials include EEs and engineers with degrees in related areas. For anyone interested in this subject, it would certainly be easy enough to take the guts of an amplifier and listen to it in a variety of enclosures, including wood, corian, steel, aluminum, carbon fiber, acrylic, glass, natural stone and such. Then one might also try strategic resonance control by not altering the material of the chassis but its geometry.

If you then have the inclination to pursue *why* things don't sound the same, nobody will hold you back. If you simply decide to use the material and geometry that sound best to you, audiophiles will forgive you.

Dennis Morecroft who has been mentioned in this thread is one of the pioneers on avoiding metals in the enclosures of electronics. He also has done work with cables and capacitors.

Relatedly, why reviewers and non-writing listeners who trust their ears continue to be referred to as golden ears is another one of life's mysteries. Perhaps some believe to be unusually endowed in that regard. Those I know do not and do not think of themselves as golden-eared.

jules · « **Reply #56 on:** 5 Nov 2007, 06:24 am »

In an audio world where similarity rules, I found Kyrill's latest post a great inspiration to alternative approaches. The apparently simple physics behind the arm on the TT still has me thinking [beyond all the wood of course] ... great stuff. It could be mad, it could be inspired ... excellent mind food.

Quote

If you simply decide to use the material and geometry that sound best to you, audiophiles will forgive you.

I would hope the "audio community" would not be quite so patronizing.

What do you actually think about wood in audio gear Srajan?

jules

Russell Dawkins · « **Reply #57 on:** 5 Nov 2007, 08:06 am »

I think that experimenters are lucky that what may be the best sounding material for chassis and cases happens to be the most accessible and easiest to work with (and arguably the most attractive).

Wood.

I say "may be" because I have not experimented with the difference.

Those who have, including in addition to Dennis Morecroft and Bernard Salabert, Yves Bernard Andre (YBA) and the designer of Mission in the 80s (the Cyrus I and II both had non-metallic cases) and, presumably, Charles Altmann, seem all to have decided to avoid as much metal as feasible. The chassis is one part that often forces a compromise for practical reasons, especially with conventional power supplies requiring large transformers.

andyr · « **Reply #58 on:** 5 Nov 2007, 08:31 am »

Quote from: Russell Dawkins on 5 Nov 2007, 08:06 am

The chassis is one part that often forces a compromise for practical reasons, especially with conventional power supplies requiring large transformers.

Much as I like the idea of having a wood enclosure rather than a metal one, I worry about the lack of RFI shielding.

So I think if you're gonna do this, you need to do what I think it was Jens who did with his GK-1 ... coat the inside of the wood panels with copper foil so he was able to make up a Faraday shield, yet only had a very thin layer of copper whose properties would not have "upset" the pure wood case much.

Regards,

Andy

Russell Dawkins · « **Reply #59 on:** 5 Nov 2007, 08:48 am »

Quote from: andyr on 5 Nov 2007, 08:31 am

Much as I like the idea of having a wood enclosure rather than a metal one, I worry about the lack of RFI shielding.
So I think if you're gonna do this, you need to do what I think it was Jens who did with his GK-1 ... coat the inside of the wood panels with copper foil so he was able to make up a Faraday shield, yet only had a very thin layer of copper whose properties would not have "upset" the pure wood case much.

Regards,

Andy

I think the thin layer of copper brings us right back to the concerns re: eddy currents voiced on page 2 of this thread, and are what I am talking about avoiding through the use of non-conductive materials in the proximity of conductors carrying signal.

I wonder how important RFI shielding is in the analog domain (except for small signal carrying conductors such as those from microphones and phono cartridges) - even for switching amps that are properly designed.

regards,
Russell