[LingLing1337]

So I am poking my head into DIY territory, thinking about ordering parts for a CMOY. Can anyone point me in the right direction? I've been reading on the TangentSoft site a bit. Is this still the preferred parts list? Would building something like a Glass Jar Audio Mini3 kit preferable for a first-time build? Thanks.

 

[Ashkii21]

I've built a couple of Cmoys and I followed Tangents guide, How to Build the CMoy Pocket Amplifier. The only things I did different were my choices of opamps besides the OPA2132, I used a gain from 3 to 5 (resistor values) instead of the gain of 11, and I used different capacitors. This was my first real DIY project and that site was very helpful. I do plan on building a BantamDAC and a Mini3 in the future now that I have a little experience soldering and building a Cmoy amp.

 

[LingLing1337]

Very cool. How much did parts run you? What sort of case did you use? And of course, how does it sound?

 

[Tomo]

How about the original article?
HeadWize - Project: A Pocket Headphone Amplifier by Chu Moy

 

[Ashkii21]

The parts were about $30, I ordered most of the parts from Digikey. The most expensive part was the metal knob for the potentiometer. I cased my Cmoys in altoid tins. I think they sound good. I am only using a single 9V battery and I've tried the OPA2132, OPA2227 and TLE2072. I like the TLE2072 the best out of the opamps I've tried. I am using a 1000uf 10V cap for C1 and a .82uf 63V MKP cap (metallized polypropylene) for C2. And my R5 is jumpered (no resistor).

 

[fortney]

The Tangent site is fine regarding the CMoy, but remember that you do not have to build it as tightly packed as he does. He intends to fit it in a Altoids tin.

Be sure to use an op amp mounting device (?name) so you can change op amps if desired or if you damage one.

I used 0.47 uF input caps instead of 0.1. and 470 uF instead of 220 uF in the power supply.

You can buy plastic polycarbonate boxes to put it in. They are easy to work with when mounting contols and connectors: use the tip of a pencil shaped soldering iron to mark exactly where you want to drill, etc.

The gain default in his instructions is 11 if I recall. I think that is way to high unless your headphones require lots of voltage.

The Mini 3 is highly regarded, but some people burn their IC's when soldering them and have a very hard time getting them out to replace them. They are surface mount and require a different soldering technique.

Good luck.

F

 

[diff_lock2]

GWado - DIY CMoy / Grado RA1 Headphone Amplifier

not really a guide, but I followed this schematic. And a tle2426 vground thing.