TriAxis and GT-6 - phasing issues

[Jackie]

My TriAxis+2:90 + BOSS GT-6 in the loop has started acting up. Well, at least the FX Loop part.

I have weird phasing issues with my GT-6. There's a very pronounced phasing "cocked wah" type of sound when engaging the FX Loop, even with the BOSS on bypass or nothing engaged at all. This wasn't always an issue and while in the past it was intermittent at best now it's constant.

I have tried:
- different leads, guitars
- using only one channel instead of both
- using different output select settings on the GT-6
- using different output level parameters (output knob dimed+low master patch level vs. output knob around 50% and master patch level around 100 +/- 10)
- I once reseated (not sure if replaced) the V5 tube and it helped for a while but now it won't stop.

I haven't checked if there's a grounding issue but since I've ran the rig on this power strip all the time this shouldn't be a problem.

I also have to check if it's just the Lead 2 channel that's exhibiting this.

I'll do some more testing perhaps tomorrow if I find the time but until then, any suggestions?

BTW I'm also sure it's not the GT itself because I tried it with my other amp, no phasing.

 

[tonefordays]

Are you using balanced cables by chance for interconnections? If so, don't.

 

[Jackie]

Nope, all mono unbalanced guitar leads.

 

[Jackie]

I'll try replacing the V5 and see what happens. Turns out I didn't replace it the last time I did this. Since it's totally random I guess that tube's about to go. Will report once I can get my hands on my Mesa again.

 

[Screamindv]

I had a similar problem. Open your Triaxis on top and remove the ribbon cables and clean the contacts with deoxit or a similar agent 1 at a time. This should fix the problem.

 

[Jackie]

So I spent around 45 minutes jamming with different guitars and such and I couldn't recreate the problem. :?

Usually the problem appeared either right away or after some time (not more than 20mins or so). The only thing that was different was I used my 2x12 cab instead of my 4x12, any way that could be connected?

 

[Hodiamonti]

Hello to all,

Even though I read a lot on this great forum already, I did not register untill 15 minutes ago.

I have this same kind of problem. About 6 months ago I sold my Marshall JVM410H (which I regret somehow) so I could buy this 20/20 and TriAxis. Other units did not change, I just wanted to have everything packed and cabled in a rack for ease of use in live situations.

So this is my total setup:
- Mesa Boogie 20/20
- Mesa Boogie TriAxis (v1.0)
- TC Electronic G Major
- Marshall 1936 Vintage 2x12" Speakercab
- Morley Mark Tremonti Power Wah
- Voodoo Lab Ground Control Pro
- Shure SLX4 receiver & SLX1 transmitter

I always used to have the G Major in the effects loop with my JVM as mentioned in a sticky thread on the JVM forum. Worked perfectly and always sounded crystal clear. Note that I always had the loop engaged so I never had volume drops when switching different effects on or off separately or channels. Then I got this Mesa setup. First read the manual and some threads up here and cabled it via the FX loop of the TriAxis in stereo. In the TriAxis I have a Mesa Boogie SPAX7 tube for V1. The other four are loaded wih JJ ECC83S preamp tubes. Two out of four poweramp tubes died very soon after buying this. Replaced all of them for Bugera EL84's. However, problems weren't solved as yet.

So I got this same kind of problem and it only occurs when using the FX loop which freaks me out and gets me banging on my rackcase. Then the phasing / volume dropping and actually flipping on and off of the loop disappears... for some minutes. It comes back every now and then. Sometimes immediately after starting up (always waiting about 10-15 minutes to have the tubes warmed up) but sometimes after say 15 minutes, or 30 minutes. When I turn off the loop on the TriAxis the problem is all gone. So I thought it would be the V5-tube which is used for the FX loop. Swopped it out for a new JJ ECC83S, problem still there. Swopped back this tube so I have this new one as a spare. Nowadays I have my G Major hooked up with four cables between the preamp and the poweramp as mentioned in schema #3 in the TriAxis manual. However I don't like this as much as in the loop. There's remarkable more hiss en fuzz in the higer gain modes and settings.

I do not know a lot (or anything?) about technician stuff and I don't have a clue what this problem could be. It's not the tube. It only occurs with loop engaged. Could this be a jack input socket failure of the send or returns? I'm so clueless at this moment that I want to kick this thing out and buy a Roadster or back to a JVM.


Any advice appreciated!


Dennis

 

[Jackie]

For some reason my issue went away... Did two rehearsals and a gig with the Mesa and no trouble. :?

 

[Jackie]

Aaaaaand here it is again. One day before recording :evil:

I've established that the problem is definitely the FX loop itself. It doesn't work, or it works partially.

If I set up a mute patch (all levels on 0 and using the bypass/mute function) on the GT-6 when everything works normally, there is silence. DEAD silence. Or if I disconnect the GT from the FX loop so that there's even connected, there is also silence.

Right now, I get a clear sound that is just quieter than the signal with no FX loop engaged, which means that there's massive bleed going on somewhere.

The other thing that pisses me off with this issue is that it seems to sound bad too. It sounds like there's a huge lack of highs, an overly "soft" sound. Definitely not the way I set it up. Which means no Mesa in the recording room. ****.

I've yet to try what Screamindv recommended because I didn't want to poke around inside. I'll try that now probably, just blow the ribbons out since I don't have any contact cleaner at hand.

EDIT: finally cracked it. It's the POWER SUPPLY. I unplugged something that shares the same power outlet and all the problems disappeared.