300b lovers

 A Cornell Dublier engineer once explained to me that the difference between a 150V rated cap and one rated at 175V was the way the cap was formed up and nothing else. Forming is a process where voltage is applied to the capacitor with a target of the rated voltage; something that is done only once in the factory.

But the cap is almost never used at the forming voltage. Usually for best reliability, they are to be run at about 80% of the rated voltage.

So the cap is not as efficient at the new voltage when new. It takes time for the cap to 'form' to the new voltage. Its important to understand that electrolytic caps have some properties in common with batteries and so are fundamentally different from film caps in this regard. Charging them and polarity are two examples of this similarity. Forming is one way they are unique.

Anyway, when the cap forms up to the new voltage used inside the amp or preamp it will be a more efficient bypass. Its my theory this is what people hear during break-in. I've found it measurable too- the voltage once the caps are formed is every so slightly higher and the supply is less noisy.

@atmasphere 

So the cap is not as efficient at the new voltage when new. It takes time for the cap to 'form' to the new voltage. Its important to understand that electrolytic caps have some properties in common with batteries and so are fundamentally different from film caps in this regard. Charging them and polarity are two examples of this similarity. Forming is one way they are unique.

Anyway, when the cap forms up to the new voltage used inside the amp or preamp it will be a more efficient bypass. Its my theory this is what people hear during break-in. I've found it measurable too- the voltage once the caps are formed is every so slightly higher and the supply is less noisy.

Ralph, this is believable and logical.

I recently had a DAC built and delivered to me from Ukraine. The builder (Abbas Esoteric Audio) told me that it will require roughly 200 hours minimum of burn-in time to sound its best. He specifically cited the Blackgate capacitors utilization as the reason. He explained to me that it takes time for these excellent electrolytic capacitors (His opinion) to form.

Sounds right to me based upon my experience with his DAC.

Charles

Ralph,

Your comments on this this thread, as on any thread, are extremely informative.   I have not had the pleasure of hearing your new affordably-priced Class D monos and maybe they will be playing at the Seattle show later this month so I could hear them then.  

You have had a career as a designer and builder of tube gear.  You now are selling a Class D amp with the new GaN technology.  Don and Lynn of course are solidly tube amplification adherents, make no mistake about that, but you seem to be straddling the line between an affinity for tube gear as well as Class D amplification. 

Are you at the point where you feel your Class D amps are equivalent to your best tube amps?  I have long anticipated that the day will come where the march of technology might render tube gear obsolete, but in the main at the moment, my experience with Class D amplification is somewhat akin to the unwarranted adoption in the 60s of lousy sounding solid state gear (everybody made a variant of it) over tube gear that took a very long time for the industry to recover from.  Tube gear, like vinyl sales, are better than they have been for a long time, but I remain dubious that Class D amps yield the same sonic goodness after extended listen sessions, than the better/best  tube amplifiers.  But then I have not heard your new Class D monos. Comments?

Lynn…. I really appreciate two comments… illusion generator… and the layman disadvantage of not hearing individual part changes…. both of which help explain why many of us go through a bunch of gear trying over and over to improve the illusion. 

Are you at the point where you feel your Class D amps are equivalent to your best tube amps?

@whitestix Yes.  After extended listen sessions as you put it I don't find that our tube amps bring anything to the party that the class D doesn't. I really doubt that we're the only ones that can do this so this has led me to thinking that tube power amps are on borrowed time at this point- that is if sound quality is the only arbiter. People do like the glow of tubes- so do I. But I've found also that I don't miss them in the slightest, despite liking tubes so much as to make a business of them.