Ampeg SVT-4 Pro Inquiry

[faster40thanu]

Whenever I power up my SVT-4, in mute of course, it makes this strange sound similar to the sound of a cartoon bomb drop (from low to high--kinda like a whistle) for about 20 seconds until stopping.

Also, while I'm at it; it also makes a very strange distortion when I turn the gain up well before I get any clipping signal. Is this a sign to change the tubes?

 

[talktalk]

would love to get feedback on this too. mine started this as well. no change in sound or anything. just that whistle that makes my heart stop for a quick second..

 

[wizay]

is it a newer model?

 

[renniw]

I have the same thing on mine, seems to be the cooling fan controller doing this.

I have a recording of it somewhere if someone want to ear it and confirm...

PM me