Marshall Amp Forum - View Single Post - Preamp Tubes?

ts31966 · 05-02-2009, 10:49 PM

I have found exactly the same thing Marty. V1 and V2 makes the amps tone. The rest of the tubes just need to be quiet. But the 5150 is set up a little differently than most amps. Channel 1 and 2 are similar but channel 3 has its own voicing.

I haven't bought a tube tester. I need to learn more. I want the amplitrex but I don't know if it is worth it for me.

Tell me this Marty, I have this tube that sounds great but on channel 3 with the gain maxed out and the guitar volume maxed out the tube starts freaking out. It makes all kinds of weird noises and the distortion from the tube is all over the place. The tube is not microphonic. The tube is a black plate brimar labeled raytheon.

Also Marty what do you know about 12dt7's. I have a whole bunch of black plate raytheons. They sound great for channel 1 and 2 but channel 3 doesn't have as much gain with them in the v1 and v2 position.

I am thinking that both triodes do not have the same gain in this tube and this is lowering the output on channel 3. I am going to have to call fender Monday about that.

Most of my tubes are old. They sound great but I think they need to burn in. Have you guys had experience with tubes settling once you leave them powered on for awhile?

05-02-2009, 10:49 PM	#225 (permalink)
ts31966 Junior Member Join Date: Apr 2009 Posts: 17	Re: Preamp Tubes? - Who, What, When, Where, Why, and How? I have found exactly the same thing Marty. V1 and V2 makes the amps tone. The rest of the tubes just need to be quiet. But the 5150 is set up a little differently than most amps. Channel 1 and 2 are similar but channel 3 has its own voicing. I haven't bought a tube tester. I need to learn more. I want the amplitrex but I don't know if it is worth it for me. Tell me this Marty, I have this tube that sounds great but on channel 3 with the gain maxed out and the guitar volume maxed out the tube starts freaking out. It makes all kinds of weird noises and the distortion from the tube is all over the place. The tube is not microphonic. The tube is a black plate brimar labeled raytheon. Also Marty what do you know about 12dt7's. I have a whole bunch of black plate raytheons. They sound great for channel 1 and 2 but channel 3 doesn't have as much gain with them in the v1 and v2 position. I am thinking that both triodes do not have the same gain in this tube and this is lowering the output on channel 3. I am going to have to call fender Monday about that. Most of my tubes are old. They sound great but I think they need to burn in. Have you guys had experience with tubes settling once you leave them powered on for awhile?