looking for a good beginning kit for a good headphone amp or a DAC

[NeilR]

Be sure to post pictures. We always like to see the results of our hard work

 

[soloz2]

lol. yeah, I definately learned a few things for next time... like get metal jacks, and I wish I had a drill press... lol.

I did notice that my amp pops when I turn it on and off. When I read the troubleshooting on tangent's site he said that it is probably caused by dc offset or something like that.
however, I measured from the IG to the outputs and didn't get hardly anything.
with my multimeter set to 2000m DC it read about 6, which I think was alright

 

[soloz2]

can anyone help me diagnose this pop when I turn the amp on and off?

 

[NeilR]

Quote:

Originally Posted by soloz2 can anyone help me diagnose this pop when I turn the amp on and off?

I don't think a pop necessarily indicates a problem. All of my amps make some sort of noise (mostly a click or pop) when they are switched on and off. I guess that is one reason AMB made his soft start board, although the main reason may have been to eliminate DC offset problems with certain amps such as the Millet Hybrid.

It may be a difficult thing to diagnose without actually hearing it and most likely it is normal.

 

[soloz2]

alright, did I measure the DC offset correctly?

 

[NeilR]

Just follow Tangent's troubleshooting guide.... measure IG to OG and that should be very low. measure OG to OR and OG to OL.

If you are getting 6mV offset from IG to OR and/or OL, as you are suggesting, that is a little high but not alarmingly. What opamps did you decide on?

 

[soloz2]

ad843's I'll measure again

OG to OR: -6.1
OG to OL: -4.2

IG to OG: -0.1

that's what I get

 

[soloz2]

And the moment that everyone has been waiting for!

both ends are off here, but it'll give you an idea of things...

the front

A closeup of the internals and front panel

The top after everything is put together

Front

Rear

And it's new home... my desk is a bit cluttered at the moment, but oh well

 

[NeilR]

Glad to see it all came together!

I wouldn't worry about the small offset you're getting.

 

[soloz2]

well I just got a package in the mail today with some OPA627bp op-amps in it

so I went to swapping the AD843's for opa627's!

the sound is not radically different, but I can tell there is some added detail to this amp. So far I've got about 6 hours on the new op-amps and I'm enjoying them very much. I think the fact that there wasn't a large difference could be that the AD843's are supposed to be smooth for AD op-amps... also and my source... x-fi xtreme music

I do have some extra opa627's though, so if someone needs some let me know