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Marshall valvestate 8040 - how to change the valve?

The marshall handbooks don't mention this yet it's well known that valves need replacing every so often. What needs to be removed to find where the valve is located?

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Hi chagzuki, you are right, but only when the valves are used as outputs, You amp has transistorised outputs, and a single tube used for distortion/gain. You will get a very long life out of this tube also because its supply voltage that is is used in the valvestate preamps is really quite low. Just enough for it to work really, so the tubes life can be expected to be much longer than normal. It is also a preamp tube, not an output tube, so they rarely need changing. If you ever did want to change it(dont bother), it is located on the PCB inside the unit. You have to slide the sleeve off to get at it. Get yourself a JCM800=the best guitar amp ever built(imho), then yo got pure Marshall tone, and output tubes that need changing every 6 months or so. Now go RIFF OUT and dont worry about your valvestates' "valve"

regards
Graeme

Posted on Mar 22, 2008

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