[hongman]

Hi all,

Using tangent's instructions and awesome diagrams, I've been getting my hands dirty building my first amp. I've built the power supply and the actual amplification portion. However, when I test the amp (using my iPod with a passthrough linked to clips, which are linked into the amp, which are then linked to the headphone), I get great sound out of the right channel, but nothing out the left. I've actually built two prototypes, and the second time, the case was reversed, in that the left worked but not the right.

What are some possible problems that could cause this? I've tried using a different OpAmp, and that didn't fix it. There doesn't seem to be any solder bridges that I can see, and the caps and OpAmp are cool to the touch when the thing's been on for about a minute. I'm not very familiar with using a DMM, but what are some of the characteristics I should be getting for voltage, etc?

Any help would be greatly appreciated. Please let me know if you need more info. Thanks!

Chris

 

[blip]

What opamps are you using? Have you checked that the actually sent you a dual opamp? They probably did, but it never hurts to check.

 

[hongman]

I'm using a OPA2132PA dual op-amp. I ordered it from Digi-key using the part number on Tangent's site, so I'm pretty sure it's correct, but I'll check on that when I go home. Could there be any other possibilities?

 

[JMT]

The 2132s are dual. Double check the pin layout (from the datasheet) as well as how you have the input and output wired.