I've just finished my first DIY project; building a BantamDac (Not the best first project to pick... damn those SMD components).
I tested all connections with a mulitmeter to make sure I soldered everything correctly (and a few times I touched leads going into the chip... but it still worked and gave the same results before/after). The Dac gets detected in Windows and I tried playing some music.
While I don't have an amp yet, I was testing using the amp for my TV. The amp is nothing high-fi and the speakers are also quite cheap. The first time I ran it, I simply had an S-video cable that I hooked to the amp and the other end (a stereo connector... well it had 3 inputs) I simply tied a wire around and to the DAC. It distorted horribly.
The connection I got for the dac is a stereo miniplug, so I pulled it out, inserted the miniplug from the S-video into it and loosely connected wires to the leads and ran it. It played much better and I don't think I noticed any serious distortion (although the quality I can't judge on this hardware).
So then I went ahead and soldered the wires, single, tinned, insulated wires for the two channels and a braided exposed wire for the ground, wrapped around the other two wires and the whole thing wrapped in electrical tape with only the very ends exposed. When I ran it through the S-video cable, it distorted horribly again. There was evident clipping and an electrical/warbly/buzzy sound on the peaks.
I can't figure out what's wrong. When I tested the resistance of the wires from the miniplug connector to the pads, they all gave ~0.3 Ohms (the wire itself gave 0.3). There is no resistance across the signal path on both channels and they both distort equally bad. I think they are properly shielded and I checked the soldering on all the through-hole caps and they look good.
The only other things to mention are that the last two pins on the right side of the PCM2702 chip are bridged (they both go to ground) and the last two on the left side might be bridged.
Any help would be appreciated.
EDIT: I tried it out on linux and most of the distortion seems gone. It sounds OK, with some warbling still evident. I'm guessing this is because of the amp, and will try it with a mini3 when I build one.
I tested all connections with a mulitmeter to make sure I soldered everything correctly (and a few times I touched leads going into the chip... but it still worked and gave the same results before/after). The Dac gets detected in Windows and I tried playing some music.
While I don't have an amp yet, I was testing using the amp for my TV. The amp is nothing high-fi and the speakers are also quite cheap. The first time I ran it, I simply had an S-video cable that I hooked to the amp and the other end (a stereo connector... well it had 3 inputs) I simply tied a wire around and to the DAC. It distorted horribly.
The connection I got for the dac is a stereo miniplug, so I pulled it out, inserted the miniplug from the S-video into it and loosely connected wires to the leads and ran it. It played much better and I don't think I noticed any serious distortion (although the quality I can't judge on this hardware).
So then I went ahead and soldered the wires, single, tinned, insulated wires for the two channels and a braided exposed wire for the ground, wrapped around the other two wires and the whole thing wrapped in electrical tape with only the very ends exposed. When I ran it through the S-video cable, it distorted horribly again. There was evident clipping and an electrical/warbly/buzzy sound on the peaks.
I can't figure out what's wrong. When I tested the resistance of the wires from the miniplug connector to the pads, they all gave ~0.3 Ohms (the wire itself gave 0.3). There is no resistance across the signal path on both channels and they both distort equally bad. I think they are properly shielded and I checked the soldering on all the through-hole caps and they look good.
The only other things to mention are that the last two pins on the right side of the PCM2702 chip are bridged (they both go to ground) and the last two on the left side might be bridged.
Any help would be appreciated.
EDIT: I tried it out on linux and most of the distortion seems gone. It sounds OK, with some warbling still evident. I'm guessing this is because of the amp, and will try it with a mini3 when I build one.
