Knotty

Opamp Burn-in (Huge 2520 Build)
« on: March 18, 2017, 12:42:40 PM »
So, I just built up 30 new opamps for a ton of API 212s I'm rebuilding (and getting ready to build up 25 more). Just had a couple questions on Burn-in. I know that API amps and others go though a burn-in process before they ship (like lost of electronics). My question is what that process looks like. I would imagine that it would just have them powered up and running then for a period of time. Maybe running a tone through it as well? Not sure if it's really that necessary sonically, but it would be nice to know they're all running strong before I try and run a session on them.
Knotty


gar381

Re: Opamp Burn-in (Huge 2520 Build)
« Reply #1 on: March 19, 2017, 09:57:32 PM »
you mean something like this ??  I can burn in 20 at a time
using an old console PSU.  There is also a selector switch
that allows me to listen to them in Stereo pairs.

GARY
RETIRED.....  from 51yrs in Show Biz

gar2520, gar1731 and gar918 DOAs at  http://capi-gear.com/catalog/index.php?cPath=71_72
NEW Sphere section added http://gar381interests.com/gar381interests.html

pucho812

Re: Opamp Burn-in (Huge 2520 Build)
« Reply #2 on: March 19, 2017, 11:51:06 PM »
burn in is to ensure nothing fails upon first power up, if there are any problems(parts in backwards ,or a failed transistor, whatever), it will show up during the burn in phase.   having worked for companies that use DOA's liberally the burn in phase for them  was just having the opamps powered for a few hours. From there when they were used in any unit,  is when any audio testing, calibration, etc was done.
Every mic has a purpose it might be a door stop or a hammer, but every mic has a purpose.

Knotty

Re: Opamp Burn-in (Huge 2520 Build)
« Reply #3 on: March 20, 2017, 11:56:28 AM »
Wow that jig is killer!! I need to build one of those! Yeah as of now I just bought one of those fivefish opamp test jigs. So I can test poor and signal on them all before I pop them into a preamp. Just onlY one at a time haha But I may just have to do. I don't think I'll be making enough in my lifetime to build a more intense jig. But all that info on burn in is killer to know! thank so much guys!!
Knotty

Re: Opamp Burn-in (Huge 2520 Build)
« Reply #4 on: March 20, 2017, 03:53:56 PM »
you mean something like this ??  I can burn in 20 at a time
using an old console PSU.  There is also a selector switch
that allows me to listen to them in Stereo pairs.

GARY

Do you ever have pairs that don't work together?  Just curious how consistent you've found the opamps to be.  I've put "identical" VP312's together but had deviations in frequency and dynamic response.  Nothing too bad, but for an OCD jackass like myself, it drives me nuts.  I just have to tell myself if I wanted things THAT precise, i should just stay ITB.  :)

gar381

Re: Opamp Burn-in (Huge 2520 Build)
« Reply #5 on: March 20, 2017, 05:53:02 PM »
James

With the tight tolerances of modern parts,  the gar DOAs
sound amazingly consistent.  The failure rate is also less than 1% :)

What is fun to do with this rig is to compare
different DOA types set up in stereo pairs for A/B
Sound comparisons.

GARY
RETIRED.....  from 51yrs in Show Biz

gar2520, gar1731 and gar918 DOAs at  http://capi-gear.com/catalog/index.php?cPath=71_72
NEW Sphere section added http://gar381interests.com/gar381interests.html

kosi

Re: Opamp Burn-in (Huge 2520 Build)
« Reply #6 on: March 20, 2017, 07:23:55 PM »