Is the mesa V twin for real?

[Herr Masel]

I recorded a song with my band today, and I had to use a friend's mesa boogie v twin pedal, because I was stuck with nothing else. I thought it was too high gain and "metalic" but I managed to get a good sound with it. The thing is that the two preamp tubes that are in it didn't go on at any stage, not when I turned it on, not when I was playing through it, the only light in that area came from the red LED in between them (for aesthetic illusion). I didn't have time to open it up and look, and I haven't asked my friend about it yet but is there an explanation for this? I find it hard to believe (though why I don't know) that a company as big as mesa boogie would be selling an utter fake, or at least I've never heard anyone mention it before. Maybe these tubes are dead and are used in the circuit in a way that would allow it to function without them, but I don't really see the logic of doing that. Does anyone know?

[cd]

A perfectly functioning 12AX7 tube will barely "light" up.  Not even like a half-dead light bulb.  Especially if you use the kind with spiral heaters (the EH LPS). the heater filaments are almost hidden so they look "dead", but work fine.

As for the V-Twin, I don't have the circuit in front of me, but IIRC one tube is used for gain, the other is a cathode follower, and most of the distortion comes from clipping diodes.  In any case, trust your ears

[JimRayden]

You should see an orange "spot" towards the tip of the tube that is normally not there. That's the heater glowing.

Electron valves' heaters are designed to emit maximum heat at the lowest brightness. If you wanted your amp shine like a christmas tree on stage, you'll just put some light bulbs in it. Tubes amplify.

---------
Jimbo

[$uperpuma]

If you wanted your amp shine like a christmas tree on stage, you'll just put some light bulbs in it.

BWAHAHAHAHAHAHAHAHAHAHA

[The Tone God]

You might want to take a few seconds and do some research before you go around suggesting things you are not sure about.

Google is your friend.

search term: mesa boogie schematic

http://www.tubefreak.com/mesa.htm

Andrew

[fikri]

Dont trust too much on this thing, the distortion you've heard is coming from its op-amp. especially the red channel, full distortion is produced by the op-amp while the tube being used is only for colouring. It is a cathode follower driving a tone-control. I myself prefered the H&K Tubeman (especially the crunch channel). beside the tone, the price is right for me ! 

[TELEFUNKON]

to me, it`s D1-5 + V2A doing the clipment in the lower channel. Not the opamp. Notice the supply voltage.

[Herr Masel]

After I posted this I found the schematic but it was a little too advanced for me. However I am not completely clueless as some of you suggested, I know tubes aren't supposed to "light up" but there is always a small faint glow which was missing in the pedal. I didn't seriously suggest that the pedal was fake, if you read what I said I after that said that I think it might be used in a different part of the circuit, not being overdriven, and about that I was sort of right. In any case, I'm entitled to my dumb questions, thanks for answering.