#1
I've been thinking about putting new tubes in my amp and what ive noticed is that all the power amp tubes seem to come in matched pairs or quads, whereas the preamp tubes all seem to come separately

does this mean that you can buy a couple of preamp tubes separately (but i guess it would be like batterys how you dont mix new ones with old ones ) and they'd be fine?

thanks guys, also while i'm here, what would make the most significant difference to tone, a speaker swap or a tube swap? im very happy with my new amp but if i could tighten up the bass a little more and smooth out the highs a bit that would be great, or should i be looking at an EQ pedal instead?
#2
tighten up the bass? sounds like you need a new speaker although speakers and tubes both have a pretty small effect on the overall sound by themselves. you also need an eq pedal with 6-10 bands. if you master the eqs use you master the manipulation of electric guitar sound.
#3
yeah i thought a new speaker would probably be the first port of call for tightening up the bass and i've been looking at EQ pedals for a while now.

even though new tubes probably arent the best solution, just for future reference does anybody know if the preamp tubes do have to be matched?
#4
power tubes have to be matched because in a class B or class AB amplifier, each of the power tubes is kind of doing half of the work, and in the bit the cross over they have to cross over nicely, because if they don't bad stuff can happen to your tone and your amp (its like an unbalanced see saw, one side would have to work way more than the other)

preamp tubes don't matter, most amps have circuitry that has more or less all the preamp stages separate so you can go and mix brands and everything

the slight exception might be the phase inverter tube, which some people say should be matched to itself for optimum performance (because each 12AX7 tube has got 2 seperate sections in it)...but I don't think most people bother


on the other thing: I'd get an EQ pedal first (that Danelectro one is like $30, no harm there even if it doesn't work)
then a different speaker, you're going to hear way more change in frequency response than from just a different set power tubes
Last edited by seljer at Nov 2, 2008,
#5
Quote by seljer
power tubes have to be matched because in a class B or class AB amplifier, each of the power tubes is kind of doing half of the work, and in the bit the cross over they have to cross over nicely, because if they don't bad stuff can happen to your tone and your amp (its like an unbalanced see saw, one side would have to work way more than the other)

preamp tubes don't matter, most amps have circuitry that has more or less all the preamp stages separate so you can go and mix brands and everything

the slight exception might be the phase inverter tube, which some people say should be matched to itself for optimum performance (because each 12AX7 tube has got 2 seperate sections in it)...but I don't think most people bother


on the other thing: I'd get an EQ pedal first (that Danelectro one is like $30, no harm there even if it doesn't work)
then a different speaker, you're going to hear way more change in frequency response than from just a different set power tubes

thanks a lot for that description man, now i get whats going on

an EQ pedal is starting to sound like a real good idea, they sound best when you put them in the effects loop don't they? i think i heard that from somebody
#6
Quote by MichaelOfCanton
tighten up the bass? sounds like you need a new speaker although speakers and tubes both have a pretty small effect on the overall sound by themselves. you also need an eq pedal with 6-10 bands. if you master the eqs use you master the manipulation of electric guitar sound.
Speakers and preamp tubes have a significant effect on an amps tone. What are you talking about?
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