5E3 build - switch-off noise

[icd]

I've just completed a Ceriatone 5E3 combo (excellent service and support from Nik Azam).

I notice that when the amp is on and standby is on, if I then switch off (power or standby first followed by the other, it does not make any difference) there is quite a loud pop/crack through the speaker. Apart from this, the amp works fine.

Any ideas on how to suppress the switch-off noise ? or is it a "feature" of the design ?

Thanks

[Alpedra]

Well... I have a Ceriatone 5E3 and I don´t have that kind of noise... I think... I always put the amp on standby before turning off...

[jimipage]

Try installing a .047uf/600v capacitor between one leg of the standby switch and star ground.

[s2]

A .01uF across the standby switch contacts should do the trick. Ceramics are commonly used for this purpose.

[95strat]

What causes this? The 18 watt I built does this and so does my old Bassman.

[icd]

I suspect that it is a switch quality or switch design issue. It has to do with arcing across the contacts as the contact is broken. A faster break will reduce this arcing to a minimum.

[liquidsuspension]

my 18w does that too. i'll have to try a cap on the switch.