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DIY Stompboxes => Building your own stompbox => Topic started by: bwanasonic on May 12, 2004, 02:40:47 PM

Title: Opamp Burn-In?
Post by: bwanasonic on May 12, 2004, 02:40:47 PM
Following a link to Black Lion Audio in another post I found the following assertion in a article about modding the  Bellari MP105  :

"Now you’re finished. The AD826 opamp takes a while to burn in, anywhere from a few hours to a few weeks."

Is this assertion based on any sound electronic principle or real data? Or this just more audiophoolishness? Sounds a bit fishy to me.

Kerry M
Title: burn
Post by: StephenGiles on May 12, 2004, 04:36:44 PM
It depends, if used with a bass at sea..............
Title: Opamp Burn-In?
Post by: aron on May 12, 2004, 04:39:44 PM
Damn.... no wonder my pedals seem different after a few weeks! :)
Title: Opamp Burn-In?
Post by: Paul Marossy on May 12, 2004, 06:19:18 PM
Maybe that's why those vintage JRC4558s on ebay are worth so much and have magical qualities!  :wink:
Title: Opamp Burn-In?
Post by: Hal on May 12, 2004, 06:34:20 PM
_could_ there be any validity to this ?

Aren't PC CPU's "burned in" for a while when tehy're first used ??
Title: Opamp Burn-In?
Post by: Paul Marossy on May 12, 2004, 06:49:07 PM
Maybe for memory chips or CPUs, but opamps? I dunno...
Title: Opamp Burn-In?
Post by: brett on May 12, 2004, 07:37:36 PM
QuoteAren't PC CPU's "burned in" for a while when tehy're first used ??
As I understand it, it's more a check that they don't BURN OUT.  
So if your op-amp doesn't burn out, then it's burned in. :D
Title: Opamp Burn-In?
Post by: Paul Marossy on May 12, 2004, 07:41:54 PM
Burned in, but not burned out. Sort of sounds like an oxymoron...
Title: Re: Opamp Burn-In?
Post by: Paul Perry (Frostwave) on May 12, 2004, 10:12:16 PM
Quote from: bwanasonic"Now you’re finished. The AD826 opamp takes a while to burn in, anywhere from a few hours to a few weeks."
Is this assertion based on any sound electronic principle or real data? Or this just more audiophoolishness? Kerry M
My vote is for phoolishness.
It is true that for electronic de3vices, the probability of failure is highest just after manufacture, then declines, then rises again at some much later date (this is called the "bathtub curve" in the trade, and the early failure is called "infant failure mode".. how picturesque!)
But modern op amops are so good, that spontaneoud failure is virtually unknown.
Title: Opamp Burn-In?
Post by: moosapotamus on May 13, 2004, 12:10:12 AM
What about burning in new vacuum tubes, tho?
That mod Kerry is referring to also involves changing out the tube.

~ Charlie
Title: Opamp Burn-In?
Post by: bwanasonic on May 13, 2004, 01:39:00 AM
Quote from: moosapotamusWhat about burning in new vacuum tubes, tho?
That mod Kerry is referring to also involves changing out the tube.

They do specify the opamp, but it shows what a sucker I am for tube mumbo-jumbo that I would not have blinked had they claimed the tube needed to burn in, even though I'm not sure the evidence for this is any greater than for opamps. I just think it's funny to assert that "this opamp sounds different than it did a few hours ago" and assume that it's the opamp that's changed. An awful lot of variables in that equation to jump to that conclusion, I would think, chief among them being your brain chemistry. How does one tell a burnt in opamp from a *virgin* one?

Kerry M
Title: Fishy
Post by: StephenGiles on May 13, 2004, 08:19:22 AM
I'd better explain - bass at sea.............sea bass - never heard of it?
Title: Re: Fishy
Post by: moosapotamus on May 13, 2004, 01:32:04 PM
Quote from: StephenGilesI'd better explain - bass at sea.............sea bass - never heard of it?
Not sure, yet... it's still burning in...  :lol:

~ Charlie
Title: I'd buy Tube Burn in...
Post by: petemoore on May 13, 2004, 01:48:24 PM
Tubes wear out. [transistors do too? not so fast anyway].
 I think my amp mellowed a bit, but alot of that is the speaker cone suspensions loosening up.
 IIRC I read about tubes having a burn in period...not that I have noticed any problems with nice new tubes.. :D
Title: Opamp Burn-In?
Post by: R.G. on May 13, 2004, 02:02:46 PM
Burning in an opamp is the purest, most highly refined crap ever hoisted above the horizon.

There are two possible reasons someone might say this.
(1) they don't believe it and somehow profit from convincing you that it's true, either monetarily or in some perverse emotional way

or, more sadly,

(2) they actually do believe it and have managed to delude themselves that it's true.

This is in the same realm as "burning in" cables.
Title: Opamp Burn-In?
Post by: Ansil on May 13, 2004, 02:44:37 PM
you can get nice death trhows from a chip if you nuke it for like a milisecond..
Title: Opamp Burn-In?
Post by: dosmun on May 13, 2004, 04:07:04 PM
QuoteThis is in the same realm as "burning in" cables.


I buy those cheap molded patch cables and after being properly burned in (Approx 15 years) they turn into George L's :wink:
Title: Opamp Burn-In?
Post by: Brian Marshall on May 13, 2004, 10:24:14 PM
opamps under normal use in pedals never get 'hot' unless you are trying to drive a speaker with it.

the physics of capacitors leads me to belive they may be capable of 'burn in' and resistors too to a lesser extent, but in the case of resitors it is probably more like burning out.
Title: well; "IN"
Post by: petemoore on May 14, 2004, 12:09:30 AM
"IN" Sounds alot better than down, up, or out.
 If I had to have a claim made on my opamp about burning, "IN" would be the best choice.
Title: Opamp Burn-In?
Post by: zachary vex on May 14, 2004, 07:03:08 AM
rust never sleeps...
Title: Oh Yeahh
Post by: petemoore on May 14, 2004, 09:06:29 AM
I got some OA's that were 'burned in'....[also Up and Out]
 You can have 'em for shipping and handling.
 Some are already branded/piggybacked...
 Others output LOTS of heat at some point in their history, to the point where you can't touch 'em...I don't theink theres a working OA on this earth that got THAT hot.
 I have some other OA's, with a dead guys fingerprints on them too...this makes them one of a kind, no other opamp will perform, when dusted for prints, like these do.