Another Noob with a tube question.....

[Cygnus X1]

The caps have to be discharged, and a lead clipped in
to make sure they stay discharged.
"One hand in the pocket" is a good guideline but it won't keep
you from being severely shocked if you don't follow other
safety rules.

If in doubt, don't open it up!

[Scooter]

http://www.tone-lizard.com/Table_Of_Contents.htm

Thanks for the link Cyg, I have read for 2 days now. Last night I swapped my tubes, and just fot the hell of it I put a set of GT and a set of EH in. Drove my buddies nuts last night changing tubes. Anywho, not to stir up a shitstorm of debate, but I will (at least for this head) say that "tubes are tubes," none of us could tell a major difference in the sound of the amp. I'm ordering a matched quad of JJ's to try also, but so far Ruby, Electro Harmonix, and Groove Tubes sound the same to me (in this head.) Maybe the pre-amp tubes would make a difference? I don't get the sound I want without a processor anyway. Meh, more reading to do.

[Spivonious]

Yes, I've found that different brands of power tubes make little difference unless you're really cranking the amp (enough to overdrive the power tubes). 6L6 tubes have such high headroom that I doubt you could ever push the amp hard enough.

Preamp tubes will make an instant difference in sound. More/less gain, more/less compression, brighter/darker sound.

[tomanyjacksons]

The caps have to be discharged, and a lead clipped in
to make sure they stay discharged.
"One hand in the pocket" is a good guideline but it won't keep
you from being serverely shocked if you don't follow other
safety rules.

If in doubt, don't open it up!

+1:idea:

[marcus]

It's not the power amp class. The manufacturer calls it "tri-mode rectification". It has the aforementioned bridge rectifier, which is used when the switch is in SS mode and a 5AR4 tube which is used in A and AB mode. I had my friend who fiddles with amps look at the schematic and he pointed out the correct switch. I'm still confused how a single tube can be operated at anything but class A.

That is interesting. A rectifier can't really run in class A anyway so this is probably just some mode nomenclature that the amp manufacturer came up with that doesn't have anything to do with the operating class.

[Spivonious]

That is interesting. A rectifier can't really run in class A anyway so this is probably just some mode nomenclature that the amp manufacturer came up with that doesn't have anything to do with the operating class.

If you're interested, PM me with your email and I can send you the schematic. It's a little beyond my comprehension skills.

[Cygnus X1]

I found the schem and looked at it.
It has a "mode" switch on the power tubes.
Pin 8 (cathode) on two of the 5881'S.

[Spivonious]

Ah, so the switch goes like this:

Solid State -> bridge diode rectifier, power class AB
Class AB -> tube rectifier, power class AB
Class A -> tube rectifier, power class A

?

I stink at reading schematics.