Anyone know how the AC30HW works on the inside?
Got a hum when on 30watt setting but it pretty much disappears when on 15watt setting which means it's most likely one side of a Output valve or 2?
It also has a loud hum on start up which comes in when the valves warm up for about a few seconds and then disappears, is that normal?
Vox AC30 hum issue
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- Reg18
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Re: Vox AC30 hum issue
Perhaps it only knows the words on the 15W setting.
I would try some new EL84's first, maybe just borrow some if you can to test it.
I would try some new EL84's first, maybe just borrow some if you can to test it.
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Re: Vox AC30 hum issue
Do you know how the wattage switch works?sizzlingbadger wrote:Perhaps it only knows the words on the 15W setting.
I would try some new EL84's first, maybe just borrow some if you can to test it.
I assume it either turns 2 off or lowers the power/volts getting to them or something along those lines.
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Re: Vox AC30 hum issue
Why don't you swap the inside tubes with the outside tubes and see if it's still happens?
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Re: Vox AC30 hum issue
Thanks for the tip, do you know how the half power switch works?TmcB wrote:Why don't you swap the inside valves with the outside valves and see if it's still happens?
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Re: Vox AC30 hum issue
On the AC15 it just a voltage drop in the power section. I haven't seen the schematic for the AC30 so can't be sure.
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Re: Vox AC30 hum issue
Well, I figure it's going to be either cutting two of tubes out or going from pentode to triode mode - those seem to be the most common ways of halving the wattage straightforwardly.Reg18 wrote:Thanks for the tip, do you know how the half power switch works?TmcB wrote:Why don't you swap the inside valves with the outside valves and see if it's still happens?
Moving the inner tubes to the outer space would troubleshoot if it was the former mode, and if there was no change I'd highly suspect it was the latter mode - in that case, it could be worth trying a known good or matched set and see if it still does it.
Family Music Store - http://familymusic.co.nzGrantB wrote:Tony, your taste is, as always, very refined. Or as HG would say, "bloody awful".