2. amps-preamps
  3. 127274-86341

Soft Start Circuits for Amplifiers

What are the pros and cons of soft start circuits for tube and solid state amplifiers? My VAC amplifiers do not have soft start circuits and are 200 WPC.  I do notice my lights dimming due to voltage drop at power up and would imagine it's inrush current is hard on the KT 88s and other electronics?  Your thoughts would be appreciated!

normie57
5 responses Add your response
mb1audio
151 posts
 
Its used in mostly solid state application to reduce warm up time.
Ag insider logo xs@2x
gdnrbob
2,421 posts
 
Probably the best person to contact is the manufacturer. 
Though if I recall my conversations with Pat at McCormack, it seems that such devices tend to degrade sound and so they ended up removing them when doing upgrades. 
facten
931 posts
 
My tube integrated amps, DAC and preamps all have soft start to benefit the tubes. My Modwright KWA100SE SS power amp does as well.
mb1audio
151 posts
 
After reading some of the other posts, I think I may have been mistaken. I was referring to something like they put on my Ayre V-5's. Certain parts of the amp still remain on after you shut it off. It reduces warm up time.  
erik_squires
5,268 posts
 
Soft start saves the power filter capacitors and the power transformer most of all, followed by the active devices (tubes and transistors). It may also prevent your panel breakers from tripping.

DIYAudio sells some boards to make your own.

No cons.

Erik
Log in to respond
More to discover
80x80
First Sound Presence Deluxe 4.0 MKII
80x80
TriangleART P200 Tube Phonostage Editors Choice Award
80x80
VAC Statement 450S