Different case materials=different sound...ummm...explain.

[Doovieman]

I've been reading a lot of these threads where people make really beautiful amps. I'm quite impressed by the workmanship and thought that goes into these boxes, but what I don't understand is why you think that a chassis made of brush wood from Africa that is dried for 15 years will cause the amp to sound better/worse than an amp with a plain aluminum box. As an engineering student, I must say that none of that makes sense. If you were building a speaker, fine...but an amp? I'm going to guess that most of you who believe in this stuff will jump on this thread and say, "try it first then knock it." I'm not trying to insult anyone, but coming from an engineering background, this doesn't make sense to me. Anyone care to share a quantitative explanation? Thanks a lot,

Doovieman

[cowanrg]

every time i build and amp or have something open while playing, i tap on the caps, case, etc, and generally rattle the thing around a little bit.

i sleep better knowing i cant hear a bit of difference while doing that...

[jcarr]

Certainly the conductivity of the casing/chassis has an effect in phono cartridges (although I reckon that the effect in cartridges is more significant than in power amplifiers).

Surf to Google and type in

induced current lenz effect

or

induced current lenz law

hth, jonathan carr

[Doovieman]

Turntables/tube amps is one story. I want to know about semiconductor amplifiers. I don't beleive that the lenz effect has anything to do with a semiconductor. Thanks for the info though.

Doovieman

[mozikluv]

i am in consonance with dovieman that putting an amp in a wooden casing or aluminun casing would make a difference in audio sound. but am willing to try this style, i have a class A amp 20w per channel which i have build and am very much satisfied with its performance and its cased in aluminun. will let you know guys of the result. i know how this amp sound in my music room.

[Steve Eddy]

Originally posted by mozikluv
i am in consonance with dovieman that putting an amp in a wooden casing or aluminun casing would make a difference in audio sound. but am willing to try this style, i have a class A amp 20w per channel which i have build and am very much satisfied with its performance and its cased in aluminun. will let you know guys of the result. i know how this amp sound in my music room.

Hey, even if it doesn't have any effect at all, it LOOKS DAMN GOOD!

se

[analog_sa]

Why don't you just try different platforms under SS amps and listen to their effect? All components are bloody microphonic one way or another. If you can hear difference between caps and wire you posess ears with sufficient resolution to distinguish between different construction materials. If not - The engineering explanations might not be very convincing, but so what?

[Colin]

If we're talking about purely microphonic effects, it probably depends on how loud you play and how close to the speakers the amplifier sits, how it's coupled to the floor (via any shelves or supports), how well the components are mounted inside the case. Does it make more of a difference with the Gainclone because the components are usually hard wired and may be more prone to structural vibration than pcb-mounted components?

It's interesting that so many systems seem to sit between the speakers. Apart from any vibration effects, in my experience, anything between the speakers tends to detract from the imaging to some extent.

Colin

[AudioFreak]

Of course, if you use a case made of non conductive material the RFI / EMI shielding will be severely effected.

[analog_sa]

If we're talking about purely microphonic effects,

I haven't found room positioning with respect to speakers to have any meaningful effect. Structural vibration seems more important than air-borne. Also a lot of components actually produce vibrations when passing signal. I am also suspicious about the importance of RF shielding - some of the best sounds i've heard originate from amps with no amount of screening whatsoever, but admittedly they are all valve designs.