Roadster Channel 3/4 Volume loss

[lordvader]

Hi,

I posted a question on the tube forum a month ago asking about a problem I encountered regarding channels 3 and 4 on my roadster combo. Here's the link: http://forum.grailtone.com/viewtopic.php?t=26233&highlight=vol+volume+loss

Anyways, the problem I'm having is that I seem to have lost the volume on channels 3 and 4. I would have to turn the volume all the way to 12 o'clock just to hear something. I was beginning to think that it was a tube problem but I've only had my roadster since December 07. Anyone know if it's indeed the tubes or is it something else? Thanks for the help

 

[tele_jas]

If you've only had the amp a few months, I believe there is a 6 month warranty on the tubes and you should be able to take it to the place you got it and have them put new tubes in it to give it a try.

Tubes are a "gamble" sometimes....... You can get the best tubes manafactured today and still get a "dud" and have it go bad instantly or in 3 months, where normally they would last 2-3 years (or 20 + years for a preamp tube).

Something you can try is to pull all the tubes and putting them back in again, this may "jiggle" anything loose in the sockets out and make better contact. Another thing to try is to put a 1/4 inch signal cable in the FX loops in and out (a few times) to make sure it's not stuck (this happened to me once on an amp and killed the volume). Also disconnect the reverb and re-connect it to see if it's not a short in there. If you have a buddy with an amp with 6L6's, you could swap power tubes to trouble shoot......and more than likely his amp will have 12ax7 preamp tubes too, you could try those too. Last thing, check the speaker connecton to make sure nothing has pulled on it (if you can).....Oh, and make sure the send and receive levels are around 12:00 on the back.

That's all I got...... Good luck and keep us posted to what the problem is and how you fixed it?!?!

 

[miro]

I have the exactly same problem with my Roadster head and i have swapped all my tubes and it dosen´t get better.

 

[JW123]

Dont think Im trying to be a smart *** but the other night I was moving my Roadster and when I lifted the amp I switched one of the channels from 100 watts to 50 watts. It was the channel I use for leads, it freaked me out all night til I got back home and noticed the switch. Thinking about this if you were to engage the Rectifier tubes and go to 50 watts it would be a noticable decrease in volume. Just a thought.

 

[lordvader]

Just an update:

I replaced the 12ax7 tubes but still no good. I don't know if the power tubes have anything to do with it; shouldn't they also affect channels 1 & 2?

 

[andrewstcyr]

I've noticed a big volume loss on channel 4 between the modern setting and the vintage setting on my roadster??? what settings are you running your channels at?

 

[chriz_batman]

I had a volume loss between channel 3 and 4 on my road king. but i later found the reason why, which was that on channel 4 i had 4 6l6 and 2 EL34 and had it switch to diode. And when i which the tube selection to only using 4 6l6 then it became alot louder. i'm not sure why but other than that i dont hear any volume loss.... it might be your tubes

 

[Bill11]

I was beginning to think that it was a tube problem but I've only had my roadster since December 07.

Hi lordvader,

I hear what you are saying but one of my new Road King's 12ax7 tubes failed about 8 months after the amp was new/manufactured and after not very many hours of playing, so I never rule tube issues out.

And if you haven't called Mesa yet, do consider it. They have always been great to work with and may have some technical insight that could provide a simple solution.

Good luck and let us know what you find!