FX loop issue

[ChunkMonkey72]

Hopefully I can get some info here, as there seems to be alot of mesa knowledge on this site. I have been having a fx loop issue on my 3 chan triple rec. I really want to be able to use my effects loop as I prefer the tone I get when the v4 12ax7 is in use (and being able to boost volume via solo) but I am having the following problem, every thing sounds good for a few minutes then the volume and tone drop right off and its very quiet and flat, and if I switch the loop off then back on its all good again for a few minutes. I have tryed numerous mix and send levels ( even with just a cable between the send and return), I have tryed changing out my v4 12ax7, I have tryed cleaning the 1/4 inch inputs on both send and return and nothing has helped.

On a side note it must have something to do with the send end of things as I have tryed running a old peavey rockmaster pre that I have into the return and a dummy cable on the send, basically using the mesa as a power amp and the rockmaster as the pre and it runs fine no drops what so ever.

If anyone can think of something I have overlooked to rectify this issue thanks so much in advance, I have a few very small shows (won't be able to open the volume up enough type shows) coming up and don't currently have a attenuator to tame this beast down (will have to go bug MrHo soon) and would like to get a little extra tone where I can for the time being.

 

[ChunkMonkey72]

Also if I am running a cable between the send and return (ie no effect delay etc) and using a active loop what is the recommend send and mix settings to avoid overloading the v4 tube etc. I want to give it another shot at practice tomorrow. I just want to make sure its just not user error on my part but there sure seems to be alot of loop issue posts with mesa recs from what I have seen.

IE should I be noon send and 10% mix or noon or 100% etc, and if I can stop this drop from occuring I will most likely add a eq to the loop to shape the tone as I find my distortion a tad fizzy. I have been playing with my rec to one cab and my rockmaster and classic 60/60 to another and the peavey seem so fill the void in tone that my un looped mesa is giving me, but I would love to fill in the mesa side a bit more if at all possible (and to be honest I just can't stand that its not working right more then anything) it just seems wrong that a high end amp would have issues like this.

 

[ChunkMonkey72]

OK I tryed things out again tonight at practice (swapped out all 5 12ax7s and sprayed a 1/4 inch cord with contact cleaner and plugged it in and out a bunch of times) , i put a eq in the loop and set the loop to footswitch and balanced out my volume to the same level as I normally play and it sounds so much better less flub on the bass end and less fizz but again about 2/3s through a song the volume just drops to a very faint level.

And its harder to get back now too, I used to be able to switch loop off then back to on and it would work again for a bit now I actually have to hit standby and then when I turn it back on it works again for a short while.

This is driving me nuts, I get short lived tone that fails mid song (which is not a option), or flubby bass and fizz that works all night long (still sounds decent but its painfull to know that your amp can sound so much better if it was working correct.

PS i was using send about 60% and the mix at 10% as I find the more I turn the mix up the more brittle it starts to sound, ie the fizz seems to take over again.

 

[ChunkMonkey72]

I practiced again last night and set a eq in the loop turned to footswitch and didn't even turn the loop on, I still got a better tone to my and my band mates ears, but I am still getting drop out part way into a song, and as soon as i go into standby and back on it work again for a few minutes. This is driving me insane

 

[ibanez4life SZ!]

Sounds like some component in the preamp is going south...if it's fluctuating in and out like that, it is on its way out.

Take it to a Mesa tech....probably a small fix, and if you still have the warranty, Mesa will take care of you.

Eric

 

[mikey383]

Sounds like some component in the preamp is going south...if it's fluctuating in and out like that, it is on its way out.

Take it to a Mesa tech....probably a small fix, and if you still have the warranty, Mesa will take care of you.

Eric

Yep. If you've swapped out all the preamp tubes (especially V4), you've done your part.

The 3 channel heads have a boatload of stuff in the fx loop circuit. Your best bet is to have a tech look at it.

 

[ChunkMonkey72]

Thanks for the replies, I was hoping there was something I may have overlooked and could give it a shot, but I kinda figured in for repair was my next option, its past warentee as I bought it used about 3 years ago but hopefully its a cheap fix. There is a good mesa approved repair shop close to me fortunately, in Ho's electronics. But unfortunately I will not have time to take in before upcoming shows. So I will have to deal with flubby bass and fizz without the loop in use until I can get it in. hopefully this problem does not get worse and start to happen without the loop active and drop during a show until I can get it in, but so far that has never happened, so I am knocking on wood in the mean time.

 

[Metaghius]

did you get it fixed yet? If so what was the cause. Im having the same problem and already had the J175's replaced in the loop circuit but still not right.