Variac after cap upgrade

[Kevin McCready]

I wonder if anyone can tell me if I should bring my Bryston 4B to life, after a power supply cap upgrade, with a variac. I know it is suggested for tube amps but is it a good idea with solid state. I have heard the arguments for using the variac as allowing the caps to form to the applied voltage slowly when exposed to voltage for the first time. Also how fast should I ramp up the voltage on turn on? Kevin McCready

 

[Nelson Pass]

Variacs are some of the best spent mony in audio.

Highly recommended for initial fire-up, and be certain to
monitor the current when you do it.

 

[Kevin McCready]

Variac

Thanks for the response Nelson. The best thing about this variac is that it was free. I spotted it in the trash where I was formerly employed.I do have a question about how long I should spend on the turn-on voltage ramp time. There are some guitar amp rebuilders who suggest that you increase the voltage in increments of 10 volts per hour. This seems excesive because I am sure the cap will charge to 95-99% of applied voltage in 5 time constants.I am also conserned about the amp not liking low voltage for an extended amount of time, similar to a brown out. I am thinking 2-3 minutes would be fine. I may be wrong. Kevin McCready

 

[MRehorst]

If you put new caps in the amp, you don't need to worry about ramping up the voltage. If you put old caps in, then ...

MR

 

[Kevin McCready]

come again

Say What? Did you have a stroke in mid sentence? Hello are you still with us?

 

[Jocko Homo]

If you have a variac, then by all means use it. If not, they are a good investment if you do a lot of work.

Jocko