Does an D-Stile Amp need time to burn in?

[JD0x0]

Yeah it would be pretty interesting if somebody could do a study like that.
The thing about tubes is, as I understand it fresh tubes have a much better treble response than tubes that have a lot of hours on them.
Particularly power tubes.
As they wear the highs start rolling off.
But they wear slow enough that we don't really perceive the loss because we will simply turn the knobs a bit more to get the tone we are familiar with.

Ive noticed this recently. I switched from JJ 6L6's to Shuguang EL34's. at first they seemed to have much more presence, which i didnt like, then i started to like the better treble response, then i noticed they became warmer and i miss that treble response

they soound great thoughh, i hate 6l6's

[Structo]

I found this reading today.
This guy dispells many of the audiophile myths and urban legends.

http://sound.westhost.com/madashell.htm#burnin

[M Fowler]

I prefer 6L6 and 5881 over EL34s anyday.

[Luthierwnc]

As usual, I'm getting in late on this but if amps I've built didn't sound right after a certain amount of TLC, they went into the pot on Sunday. I don't play enough to wince through 50+ hours of substandard tone in hopes that it will improve. From a manufacturing point of view, that's like putting out a car with a squeaky axle hoping it will grind enough steel into the grease that the noise goes away. I seem to remember shoe salesmen telling me, "Oh, they will stretch out in no time."

Dogs don't leave the bench, sh

[Zippy]

I found this reading today.
This guy dispells many of the audiophile myths and urban legends.

http://sound.westhost.com/madashell.htm#burnin

Anyone that cites (as he does) "agitation of copper molecules" has no credibility. There is no such thing going on in cables. There are no molecules of copper.

That he ascribes a typical aging curve to the life of a tube amp is utter garbage.

[Structo]

Can you elaborate on this?

[talbany]

As usual, I'm getting in late on this but if amps I've built didn't sound right after a certain amount of TLC, they went into the pot on Sunday. I don't play enough to wince through 50+ hours of substandard tone in hopes that it will improve. From a manufacturing point of view, that's like putting out a car with a squeaky axle hoping it will grind enough steel into the grease that the noise goes away. I seem to remember shoe salesmen telling me, "Oh, they will stretch out in no time."

Dogs don't leave the bench, sh

I wouldn't consider an amp fresh off my bench with no burn in time substandard and certainly wouldn't call it a dog...Does the tone change over time (in your opinion) and do you like that change..
Everything changes with age..


Tony

[AcePepper]

Hi,
I'm surprised that noone has mentioned forming filter caps. I've been told that it takes some time to fully form the electrolytic in the filter caps and this has a pretty big effect on tone. I have seen amps that sounded like a** at first that got much better after a couple days of burning-in. I've got a new D-Type build now that's a bit harsh. I'm hoping it'll mellow after a burn-in and the E-caps get good and formed.

[BobW]

Hi,
I'm surprised that noone has mentioned forming filter caps. I've been told that it takes some time to fully form the electrolytic in the filter caps and this has a pretty big effect on tone. I have seen amps that sounded like a** at first that got much better after a couple days of burning-in. I've got a new D-Type build now that's a bit harsh. I'm hoping it'll mellow after a burn-in and the E-caps get good and formed.

Ace, My earlier post addresses this where parameter changes such as ESR and ESL change over time, whether or not if you form caps. I agree the parameters do become more stable when the caps are formed, but a formed cap doesn't imply you will like the tone of a formed vs. non- formed. A better determination of caps for best tone is to use caps that were pre-formed properly before in-circuit comparisons .

[Structo]

I didn't think it was necessary to form new caps.

I know guys that get old amps that haven't been powered up in a long time that reform them with good results but, I thought when new caps are first powered up the process happens and it's all good.

Can you point me to some documentation that supports that idea?

From my notes I have this:
A new capacitor should rapidly take a charge right to rated voltage, in which case only a small voltage drop will appear across the resistor.

[67plexi]

As transformers age from, magnetic fields, current flow, heating and cooling, resistance in the copper windings, iron core, mechanical breakdown from vibration, moisture and heat.
Ever notice a guitar amp sounds best just before the transformer dies. I have.
My best sounding amp builds; I used vintage transformers from the wise advice from Ken Fischer.
Lucky me I just scored forty year old Fender twin transformers for my #124 build.
Tony has been 100% correct take note.

Steve.

[Zippy]

Can you elaborate on this?

Which part? The "molecules of copper"?

Copper doesn't form molecules - wrong bond structure.

"Agitation" - electron flow in the form of current doesn't excite the copper atoms - it occurs in the electron "cloud" surrounding the atoms. Yes, copper migration has been demonstrated but is not appropriate to this context - copper migration occurs in thin films experiencing intense DC flux.

Making an "aging curve" is too general. It ignores any physics in the system and is nothing more than a schematic globalization, a hand waving, smoke-blowing cartoon substantiated by nothing.

Could we go back to talking about the influence of insulation color?

[ER]

Speakers and trannys do benefit from break-in, passive components not so much.

E caps are always worth reforming, you never know how long that thing sat on the shelf, I always start up old unknown equipment or new build with a light bulb limiter just in case.

After 30 years or so drawn copper has relaxed back into it natural orientation, that's why silver face and now 1980's amps are starting to sound better.

Hang on to those boogies/laneys/peaveys they'll start sounding good any day now...

You can do an A/B test for insulation color by turning the lights on and off, wire doesn't know what color it is in the dark, and usually sounds better.

-E

[Structo]

Heheheh, yeah I'll buy some of that.

How about the theory that old vacuum cleaner cords makes good speaker cable?
Something about the heavy current flow through the copper does something to the copper.
Don't know if that is true either.


Zippy, sorry the internet didn't make me sound sincere which I assure you I was.
Thanks for the better explanation.

I remember being in semi-conductor theory class years ago when the instructor was going over hole theory.
I probably looked like a deer in headlights.

I understand electron flow but sometimes conventional teaching can make me scratch my head as in electron flow or current flow.

Time for me to hit the books again.

[talbany]

Hi,
I'm surprised that noone has mentioned forming filter caps. I've been told that it takes some time to fully form the electrolytic in the filter caps and this has a pretty big effect on tone. I have seen amps that sounded like a** at first that got much better after a couple days of burning-in. I've got a new D-Type build now that's a bit harsh. I'm hoping it'll mellow after a burn-in and the E-caps get good and formed.

IC had a really good PDF on the subject.. (Cant' find it) It basically said Forming filter caps was primarily maintance/safety practice used back in the day when the shelf life of caps was much shorter than modern caps/ materials used today or like Tom says if the amp has been sitting long periods of time( although this was called reform).. Many techs adopted the technique thinking it helped prolong the caps life (although this was never actually proven) at the voltages we run..nor has it been proven to enhance or change the sonic character of the amp.. At least not that we can hear..It's one of those things that won't hurt to do just don't expect your amp to sound or perform better..

Lucky me I just scored forty year old Fender twin transformers for my #124 build.

Steve congrats on the find..
Tony :