Chassis Material

[MarshallPlexi]

I'm working on a small chassis (13x7x2) and for space sake I need to place the PT on one end of the chassis and the OT on the far end with the choke in the middle.

I'm a little concerned about OT being that close to the input section, but I have seen this done in the SLO 100 and this is amp no where near that level of gain.

So with that in mind, I'm trying to decide on a chassis material. It's either going to be 0.125" Aluminum for weight savings, or roughly 0.0625" mild steel. I'm concerned that the aluminum will not shield the input section from the OT and I'm concerned that the steel might magnetically couple to the PT and OT. Which problem is more realistic?

At the end of the day, I want the amp to be quiet which is more important than weight to me.

Thanks for the advice!

[defaced]

If you haven't already, check this thread out;
http://music-electronics-forum.com/s...ad.php?t=10216

As for weight, you're looking at a difference of a little under a pound with aluminum being lighter (3.11lb vs. 2.29lb). I didn't take into consideration the pieces that will be removed from the corners to make the box, but it's a good rough order of magnitude estimate.

I also shaved down the thickness of the steel to 0.0589, which is the actual thickness of 16ga steel, which is more than likely what it'll actually be made of (not that 0.0036" makes a whole lot of a difference).

[MarshallPlexi]

Great article thanks! I'm really leaning toward steel. It's cheaper, stronger and will shield the components from the magnetic fields that the iron puts out. I'm not really worried about the conductivity of the material since I'll be using a star ground with only two grounds on the entire amp. Thanks man!

[defaced]

Careful about the strength comparison, there's more to it than perception.

If you get this made of aluminum, we'll figure you'll be using 6061-T6, it's extremely common and available in the thickness you're working with. If you get it made of steel, it'll probably be 1008 which is common sheet steel. Figuring the same material thickness, the 1008 is weaker by about ~20% but is about 200% stiffer than the aluminum. Now considering that you'll be using aluminum that is 2x the thickness, the aluminum chassis will be alot "stronger" than the steel chassis. But it's an amp chassis, either material and thickness will work.

[daz]

My OT is fairly close to the first stages and even tho the amp is very high gain it's very quiet.As quiet as any production amp i've owned ! My chassis is aluminum.