LSC Power Tube Rules

[Musical123]

Hi,

I recently bought a used LSC v1. Are there any rules, written or un-written in regards to the Power and Rectifier tubes?

What I mean by this is can you replace just 1 tube at a time? Do it in pairs? mix and match manufacturers? Whic two are for 50W etc...

Any advice or stories in regards to power tubes is appreciated.


Regards

 

[djw]

I think Power Tubes and Rectifier Tubes are two different categories... the tubes used in these stages are definitely not interchangeable. As far as replacing the rectifier (5U4GB) goes, most of folks seem to wait until it starts to fail before replacement; tonal advantages to upgrading a functioning 5U4 seem to be limited. YMMV.

As to power tubes, it's best to work with pairs, and the pairs match the two inners and the two outers... so if you look at the four power tubes and number them L-R 1,2,3,4, the pairs are 1 & 4, and 2 & 3. The outers (1 & 4) are your 50 watt setting drivers.

 

[MrMarkIII]

Rectifier tubes perform a totally different function than the power tubes.
Their sole job is to take the A/C from the wall and convert it to the D/C used by the amp. Tube rectifiers are very old-school, having been phased out 50 years ago, as when Fender went from Tweed to Blackface. They are inherently more inefficient than their solid state replacements, so were re-introduced in the "booteek" market to achieve the elusive vintage sound.