Chassis make and material

[JamesO]

Last week Funk's chassis offer confused me. I wasn't sure why someone would go for a $200 chassis set. Yesterday I was speaking with someone about what they're doing, and they're also using a thick chassis (not made of aluminum, but I don't want to give away what they're doing).

It made me start wondering: will the thickness or density of a chassis, or material that it's made out of, effect sound. I understand that a heftier chassis will have structural benefits that a thinner one won't, but what are some of the other benefits?

Allesandro amps is offering a 24k gold chassis upgrade for $40,000....

[odourboy]

Well I don't know about that gold upgrade! but aluminum is a desirable material for chassis building because it's conductive - thus providing a barrier to electric fields (Faraday cage concept) but it's non-ferris, so it does not conduct the magnetic fields created by the transformers and of course it's light weight.

Further, a 1/8 welded chassis is a damn sturdy and desirable base to build an amp on! Punched, powdered and with boards, you'd be extremely hardpressed to find a better deal.

[bnwitt]

Its been awhile since you've checked Allesandro's prices. The 24k gold chassis are up to $50k. Darn, I should have bought one. I could have made $10k buy now.

[Chad]

[quote="Further, a 1/8 welded chassis is a damn sturdy and desirable base to build an amp on! Punched, powdered and with boards, you'd be extremely hardpressed to find a better deal.[/quote] I myself would like to see if you could find a better deal. Chad

[bnwitt]

Last week Funk's chassis offer confused me. I wasn't sure why someone would go for a $200 chassis set. Allesandro amps is offering a 24k gold chassis upgrade for $40,000....

So what are you saying? It's a ripoff?

I myself would like to see if you could find a better deal. Chad

Then get with it pardner. Do yourself some research and you'll find that a chassis is $100, plates are at least $60 with you doing the artwork yourself, and a single unloaded board is $40 and up. That's already $200 and you're still missing other PC traced boards that are needed for the ODS. Be sure to share your findings with us all when you're done.

As it is now, Funk is providing a chassis, silkscreening and multiple boards for $195. Plus he's driving all over hell and half of Georgia to provide it. Until Mojo or Ted Weber hire some scummy child abuser in China to do this (and expose themselves to cease and desist orders from Mr. D) I guess we'll just have to pay the hard working American craftsmen in Colorado to do the job instead of those disadvantaged teenage farm girls in Chinese sweatshops. Of course once that happens we'll get cheap chassis that change colors over time like a 70's mood ring. A few years ago I bought a made in China brass saxophone. Guess what, It ain't brass no more. Oh and I can get a fantastic deal on Chinese dog food. But, I love my dogs.

Maybe converting a Valve Jr. is a better choice for the budget minded than taking on a precisely accurate Dumble ODS with the best of materials one can find.

One needs a dedicated passion to do this sort of thing. Sorry for stating the obvious.

[Funkalicousgroove]

Aluminum was chosen for it's conductivity and imperviousness to magnetism. the thickness was chosen so that we could use 100W transformers, and to keep it close as possible to the original.

Certainly doesn't compare to the quality of a Hammond box build though...

[JamesO]

So what are you saying? It's a ripoff?

It made me start wondering: will the thickness or density of a chassis, or material that it's made out of, effect sound. I understand that a heftier chassis will have structural benefits that a thinner one won't, but what are some of the other benefits?

Did you really miss this?

[bnwitt]

Did you really miss this?

Maybe it was the comparison to the rediculously expensive solid gold chassis and the query "why somone would go for a $200 chassis set..." that threw me. It certainly seemed by your remarks and the comparison you gave like you were saying $200 was a lot of money. Did I misunderstand your point? If so I apologize.

[skyboltone]

So what are you saying? It's a ripoff?

It made me start wondering: will the thickness or density of a chassis, or material that it's made out of, effect sound. I understand that a heftier chassis will have structural benefits that a thinner one won't, but what are some of the other benefits?

In case we missed it.

James, I saw your post in the beginning and decided not to reply because there is so much confusion and weirdness around these issues.

You can make a chassis out of wood. We used to do that with little one tube radio circuits when I was a kid. A metal chassis acts as a shield and a structure to isolate "hot" parts from the exposed parts like tubes, cap cans, transformers, etc.

As electronic circuits, especially high energy ones, radiate electromagnetic fields, I think that a fine ear would be able to discern differences between steel and aluminum chassis'. The size of the chassis will also create subtleties as well, given the differences in layout distances between components. In the DIY hi-fi, world, as in this one, a great deal of attention is paid to component types and construction because of the way the fields generated by components interact with one another. One of the first jobs in tweaking a new amp is to adjust wires and components so that interactions don't create sonically detrimental effects. In other words, try moving around the grid wires from the PI to the power tubs some day. Oscillation can be either started or stopped by that action alone.

Now, having said all that. Can one hear the difference between an .04 chassis thickness and an .09 one? I don't know, I doubt it. But drop a 50 or 100 watt amp made with these thickness' from 12" to a firm surface and the differences will become apparent quickly.

Trust me, I've some experience with this, Brandon's chassis are the very very best materials and workmanship. To duplicate it locally will cost you more. Lots more.

Hope this is helpful

Dan H

[Funkalicousgroove]

the benefits of aluminum:

Better conductor than steel-faster response/slew
Easier to work with- easier to punch/bend/drill
Lighter in weight- self explanatory
Impervious to magnetism-does not conduct transformer noise (this is a curse and blessing in that if you are playing near a power station you have no shielding from the transformers)

Benefits of thicker chassis:

More rigid/sturdy.
will support heavier trannies/components

[JamesO]

Did I misunderstand your point? If so I apologize.

Funk's chassis was the first time I'd ever seen a more expensive chassis. I understand more about that now. This post really isn't a passive agressive thing---I'd just like to learn more about it.

[JamesO]

Thanks guys. That's exactly what I was hoping for.

[brownnote]

There's another aspect that is often overlooked...microphony.

Vibration can be a problem in higher gain amps, from a mild annoyance to full out oscillation...the thicker chassis has a greater dampening effect.

Trainwrecks were built on a very lightweight BUD chassis, and you'll notice many of them have weatherstripping stuck to areas to reduce resonance.

[Chad]

I myself would like to see if you could find a better deal. Chad

Then get with it pardner. Do yourself some research and you'll find that a chassis is $100, plates are at least $60 with you doing the artwork yourself, and a single unloaded board is $40 and up. That's already $200 and you're still missing other PC traced boards that are needed for the ODS. Be sure to share your findings with us all when you're done.

No Barry I got a danm fine chassis from funk almost 2 years ago and I was saying that I DON'T believe someone could ever find something of this quality as what Funk is ofering now and if I wasn't so broke now I would deffenitly buy from him again.And if and when I do get $200 I hope Funk has 1 more for me. He has help me imensely just as you have on Hoffmans board and thoughout my amp building experience which now includes 8 of my faverite amps and I thank you all. Chad

[bnwitt]

Man I must have had a mini stroke when I was reading those posts. It seems like I missed everyone's point. What can I say, I'm an idiot.