S1 45 Combo: quiet whistling when idle?

[Craig2SM]

Hi all,

I've had my Series One 45 for 2 years now still on stock tubes. I'm a newbie when it comes to valve amps and just now my amp has developed a sort of whistling noise when I just do nothing on the Super Crunch & Crunch channels (sort of sounds like a Sonic Screwdriver from Doctor Who, if you get me) - does this mean I need to change the tubes? I've tried other guitars through it with the same effect, with my effects board, without my effects board and with different leads.

If I do need to change the valve, any recommendations?

Thanks.

[majikmojo]

since they are 2 years old the tubes would be the first place i looked - thats the culprit more than likely
as far as what kind...thats all up to you - its very subjective

in general i would stay with a good brand such as JJ,Tungsol,EH,Mullard

[ronnie robinson]

Sounds like a microphonic tube - with 2 years use its time imo to replace all the tubes - I tend to replace mine every year

[Bigsmudger]

My 45's about the same age but thankfully no issues like that as yet.
Def worth a change of valve - I'm looking at JJ Cryo when mine goes in for a service.
Watford valves were putting together a full revalve kit for the S1 a few months ago.
If I remember right it was gonna consist of Harma Cryos and cost around £100.

One further thought - don't suppose it's picking up some external interference?

[WildBillMojo]

Sounds like a dodgy tube to me. You can sometimes see them glowing extra hot when they're on their way out; have a look inside the back when it's warmed up.

I had a poor experience of JJ's on a previous amp. When I needed to change 'em on my S1-45 I used Electro-Harmonix (only 'coz they were not that expensive) and absolutely love them; much better than the stock tubes IMHO. Warmer, sweeter and less brittle, particularly at volume.