I have some decent tubes in my Carver C-19 pre/phono-pre.
These NOS Mullards are precious to me, a gift from the maestro who did the mods as directed by another maestro, Bob C.
A while ago I read this article from Perkins Electro-Acoustic Research Labs (PEARL).
As with many components, heat is THE enemy.
Tubes were a crucial component of the technology that preceded today's IC chips.
Their importance in the technology that was advanced at a blinding rate was paramount during the 2nd World War.
Used in all radar & communications, they were the backbone of the military & their reliability was paramount.
As such, there was extensive research conducted.
This article relates some of the results of those investigations.
Figure #3 on page 6 is of great interest to me.
Seemingly minor reductions in tube temp can result in significant increases in tube life.
I just placed an order for 4 Pearl coolers to wrap the 6922's residing in my C-19.
There may be additional benefits from the damping effect (microphonics).
I will update with my impressions once they arrive & I have time to do some comparisons.
These NOS Mullards are precious to me, a gift from the maestro who did the mods as directed by another maestro, Bob C.
A while ago I read this article from Perkins Electro-Acoustic Research Labs (PEARL).
As with many components, heat is THE enemy.
Tubes were a crucial component of the technology that preceded today's IC chips.
Their importance in the technology that was advanced at a blinding rate was paramount during the 2nd World War.
Used in all radar & communications, they were the backbone of the military & their reliability was paramount.
As such, there was extensive research conducted.
This article relates some of the results of those investigations.
Figure #3 on page 6 is of great interest to me.
Seemingly minor reductions in tube temp can result in significant increases in tube life.
I just placed an order for 4 Pearl coolers to wrap the 6922's residing in my C-19.
There may be additional benefits from the damping effect (microphonics).
I will update with my impressions once they arrive & I have time to do some comparisons.
Comment