[aeriyn]

Just out of curiosity, I tried rolling my AD8620 opamp out of my PIMETA for an OPA2227 that I've got around. So, I power the amp off, pull the existing opamp, set it in an anti-static bag, then plunk the OPA2227 in.

Power on, play song... CRUNCHCRUNCHCRUNCH. Clipping... What? Put old opamp back in. CRUNCHCRUNCHCRUNCH. More clipping.

It was working fine just a few minutes ago. o.o Any ideas?

 

[enemigo]

I had a similar experience once. After a LOT of troubleshooting I found out I had loosened a (poor) solder joint for the opamp socket.

Knut

 

[aeriyn]

Oh boy. Just what I wanted to hear. X.x;;;

Guess I should get checking, then.

Supply voltage checks out though, 18V. Hrm...

 

[Edwood]

Is there really loud popping noises when you plug in your headphones regard less of volume?

Make sure you put the OPAmpst in correctly. Oriented correctly.

Also, be careful not to plug in Ground OPamp into LR and vice versa. I fried a pair of OPA627's by putting them in the Ground one by accident. Either that or they were DOA to begin with.

-Ed

 

[aeriyn]

No, it's just clipping. Like it's not getting enough power. Distortey, crunchy clipping.

Offset on the outputs is <2mV, so whatever it is hasn't messed the circuit up enough to produce offset voltage.

The correct opamps are in the correct slots. lol

 

[skyskraper]

what happens when you put your old op amps back in? another thought may be that the opa2227 isn't seated correctly in the sockets....

 

[aeriyn]

Quote:

Originally Posted by skyskraper what happens when you put your old op amps back in? another thought may be that the opa2227 isn't seated correctly in the sockets....

I said in the first post that the old opamp clips too. Both the OPA2227 and the AD8620 are clipping now. -.-'

Voltages on the pins look correct, though.

 

[myself, aka me]

dead bug? maybe you fried 'em both.

Maybe some wire is fooling around with another conductive piece of the amp. Could be a ground wire has come loose.

 

[enemigo]

So, it wasn't the socket, too bad...

Check for lose ground wires perhaps...

Knut

Edit: Not quick enough, "myself, aka me" beat me to it

 

[aeriyn]

Quote:

Originally Posted by myself, aka me Could be a ground wire has come loose.

Bingo. This is what I get for hand tightening my panel mount RCA jacks.

Tightened them up with pliers. No more "clipping."

 

[enemigo]

Good!

Any thoughts on the differences between the 2 opams? Just got the OPA2227 myself. I'm having problems finding the AD's up here.

K

 

[aeriyn]

Quote:

Originally Posted by enemigo Good! Any thoughts on the differences between the 2 opams? Just got the OPA2227 myself. I'm having problems finding the AD's up here. K

From my little test right now, the OPA2227 sounds very good for a 3 dollar opamp, very good even compared to AD8620. It's not quite as nice to my ears as the AD8620, but it's very close match. Has a slightly different sound signature... not as "in your face." More mellow. Works better with brighter headphones, like Grados. My Beyers appreciate the high-end lift the AD8620 gives them though.

 

[Jazper]

Quote:

Originally Posted by aeriyn Just out of curiosity, I tried rolling my AD8620 opamp out of my PIMETA for an OPA2227 that I've got around. So, I power the amp off, pull the existing opamp, set it in an anti-static bag, then plunk the OPA2227 in. Power on, play song... CRUNCHCRUNCHCRUNCH. Clipping... What? Put old opamp back in. CRUNCHCRUNCHCRUNCH. More clipping. It was working fine just a few minutes ago. o.o Any ideas?

did you knock or short anything?

edit: damn, I'm slow off the mark tonight

 

[Edwood]

Whew!

This is the "fun" type of troubleshooting where it's just something simple that has come loose.

Not the other "fun" type of troubleshooting where you have to replace dead components.

-Ed