[ozshadow]

I picked up a etching kit at a RS that was closing the other day for $4. I figured I would give it a try. It was a lot more work than protoboard, but a much cleaner result.

The amp is an A47 design running on 27 volts with two OPA2107 chips in it, and two 1000uf caps. It uses resistors to split the rails, as I had no railsplitter on hand, but I intend to build one of those soon with a different, smaller two sided design.

The amp sounds great. It has improved detail and soundstage over a similar cmoy, and the bass is tighter. I gutted a cmoy from that case, as I finally had something big enough to fill it. There is no noise to it whatsoever.

It must sound good, because my fiance stole it and has been listening to it ever since like, 3 minutes after I confirmed it was done.

Below is the initial transfer from a transparency.

Next, we have it with the copper removed.

And here it is with the copper cleaned off and the holes drilled - I could not find a 1/32 bit, so I had to use a 1/16, which required some creative soldering and hole placement.

Below, you see all the components added

The bottom, sorry its so fuzzy, but its already in the case, so no new pic, but let me tell you, there is some very precise soldering under the opamp sockets.

And finally, here it is COMPLETE and working ! It has a cool purple-blue light by the way, to match the midnight blue case.

I am very pleased with the way it turned out.

 

[Pars]

Nice job!

 

[AtomBoy]

Nice work- congrats!

What transparancy film did you use for the transfer and how was it?

I've been using inkjet photo paper and its a very squirrely process with the wrong brand. Staples Photo Basic item# 471861 is whats working best so far, but it could be better.

 

[ozshadow]

I had Kinko's copy it on their stock film. Next time, they need to go heavier on the toner than they did. I had to touch up the traces with a sharpie and draw about 1 inch of one completely.

 

[Voodoochile]

Nice job! The board (and amp) came out well.
What's up next?

 

[ozshadow]

A47 on duel sided etched board with railsplitter and buffer, and probably a couple PPAS's, all about the same time in August.

In the mean time, a few more Cmoys to give away.

 

[MisterX]

Not to bad.

It's a shame that BoyElroy is not around to see what you did with his artwork.

 

[ozshadow]

I really love the sound which is wider and more dynamic than the single opamp Cmoy, but I did not realize I can't experiment with combining two different opamps in this layout for combined sound signatures.

 

[Garbz]

nice now make it smaller

 

[ozshadow]

Ahh, I thought about making it smaller but I already had that case setup with a cmoy and have cmoys in mints, so it seemed kindof a waste to have one in that case. This gave me an excuse to use it.

I plan to squeeze an A47 in a mint with 2 9 volts soon using a different two side design, but up first, I am going to concentrate on a PPAS which will be going in a nice Hammond. I have two boards, so I may make one super tiny.