Roadster FX loop crackling

[CAR-15]

I recently purchased a Roadster head. It sounds great! only problem I am having is that when I click the FX loop switch on the back to use my G Major 2 it "crackles" for lack of a better word. It does this on and off the whole time the loop is engaged. When it is off the amp is perfectly quiet. I tried moving the tubes around with no luck. I even tried some old tubes I had with no real change. Any suggestions?

 

[blackoutshred]

Well... like always.

1- double check on the v5 with a known good pre-tube.
2- connect a patch cable on the FX loop to narrow the issue.
3- take a look if this happend on every channel with the fx engage or only on the drive ch's, if only happend on the OD ch's the issue may be on the drive stages preamp tubes (v1-v2-v3).
4- try to disable the FX loop switches on the back of the amp and only enable it using the pedal.
5- cables, cables, cables.
6- check the fx unit in another amp just to be double sure that it works fine.

7- take it to a mesa tech.

ps: don't forget to post back your findings and eventual solution. hope the best for you.

Alan.

 

[CAR-15]

Over the last week or so I have tried everything that I can do to resolve the issue but unfortunately I can't get it fixed with tube swaps and I have swapped them all! Also, since I posted the OP the crackling and popping has gotten worse and is there in every channel whether the FX loop is bypassed or not.

I dropped it off this morning at a authorized Mesa repair facility to have a tech look at it. I am guessing it is a electronic issue with a FET or resistor or something!! I hope to get the head back next weekend, maybe a week after that. I will find out from him what it was and report back. I appreciate the help! The bad thing is I just got a Jim Root Telecaster yesterday! Now I am without an amp!!

 

[CAR-15]

Got the amp back from the repair guy all excited to get home and rock. Hook it up and it is still making the exact same noise. He said he replaced 2 resistors in the effects loop that were noisy. He said he played it and was fine. That is not the case. Bummed as hell, the head is going back first thing tomorrow. I'm sure it will be at his shop another 2 weeks. This sucks. All I want is to rock out with my rig and I keep having problems.

 

[Given To Fly]

Sorry to hear about your Roadster problems. I recently had the same problem but it was not limited to the FX loop, the crackling and white noise was present on all channels. After the amp warmed up for about 30 minutes the crackling stopped but that was not really a solution. While this was probably overkill, I simply bought a Roadster Tube Replacement Kit from Humbucker Music and upgraded all the 12AX7's to SPAX7 preamp tubes. I was tempted to try a different type of rectifier tube but chose not to this time around. The amp is back to normal, sounds great, and is dead quiet. I do not know if this would be a solution for your problem but I thought I'd mention it. I hope you get it sorted out!

 

[CAR-15]

Thanks man, I appreciate it. I took it back this morning. I was literally there the moment he opened the door. He was surprised to see me. I asked him if he could put it on the bench so he could hear it himself. Fired it up and heard the noise immediately. Told me "That is a tube". I told him it wasn't. I had tried different tubes and it wasn't any different. He swapped tubes while I stood there and different tubes made no difference. He said it was strange. He said he would get with Mesa on Monday and get the info. Said it probably was a resistor. We'll see how it goes. I'm bummed. Wondering if I made the best decision buying this amp. I love Mesa gear but this amp is hurtin' feelings.

 

[Given To Fly]

I would be bummed too. Out of curiosity, did you buy the amp new or used? Also, how much confidence do you have in the amp tech you took the Roadster to? One reason I bought my Roadster was because if you buy Mesa tubes you do not have to bias the amp. I have no technical skills when it comes to building or fixing things. I changed the tubes in my Roadster twice now and once in my Rectifier Recording Preamp. If a problem still persists, I'm allowed to say "That's strange," not the authorized Mesa repair technician. :shock: And if he already replaced 2 resistors in the FX loop, he should not be saying "its probably a resistor" the second time around because that means he did not actually fix it the first time. :shock: Right? Or am I missing something?

All of my Mesa amps are out of warranty but the customer service I have received from Mesa has still been superb. If the problem persists, I would contact Mesa directly. If they tell you to take it to the nearest authorized Mesa Repair technician, box up the amp and send to the factory in California. I know that sounds drastic but "the squeaky wheel gets the grease." :wink:

 

[CAR-15]

I have lots of faith in the technician. He has a stellar reputation and does fantastic work. I think he didn't listen to me real well when I took it in the first time and thought it was just an FX loop problem. He fixed that but only played the amp on clean to test. The crackling and popping show up best on channels 3 & 4. We will see what happens but whatever it is I am confident he can fix it.

 

[CAR-15]

Got the amp back this afternoon. Hooked everything up and it seems good to go. Plugged in the G major 2 in the loop and it sounds great. Every channel is quiet and is finally like I expected it should be. He said that it was a resistor in the V1 path. Hopefully it stays this way. Had a helluva good time playing for about an hour earlier. Now I just have to figure out all of my MIDI stuff!! :shock: :shock:

 

[Given To Fly]

Good to hear! I was being hard on the amp tech because the musical instrument industry is not impressing me at the moment. However, seeing as you now have a fixed Roadster he obviously did know what he was doing and did I mention you have a fixed Roadster? :lol: Enjoy the heck out of it!

 

[CAR-15]

LOL, thanks man. Yeah, it is fixed but I find myself stopping and listening for any little noise now! Paranoid something else will go wrong. I just need to put it out of my mind and play the bitch!!

 

[bandit2013]

Your issue is easy to misdiagnose. Often times preamp tubes will begin to create noise, crackle as you say. I usually find this to be more prone with the Mesa branded JJ tubes, other brands are just as prone but I have encountered more issues with the stock tubes. So far I have had no issues with my Roadster to date. I have had issues with my Mark V (generally with all tubes) and a few with the Mark IV (typically noise as you mentioned), however, tube swaps usually cure the issue.

I can understand your frustration and I am glad to hear you are up and playing again though the Roadster.

 

[Shaun]

So that fixed it right up?
I've got a road King (2) and the EXACT same problem and symptoms. How much did it cost you to get fixed? It's been bugging the hell out of me for the better part of a year!

 

[andross182]

What ultimately wound up being the issue?

 

[peterdenny]

Guess I am lucky I dont have any issues with that via my FXLoop (RK2 combo). Now punjabi radio is another issue. I suspect someone is broadcasting a pirate station on the weekends and not sure where I am picking it up but seems tied to the ebtech between my g-system and the rest. I totally get your frustration in hunting down things. Glad you got it fixed. Never take no for an answer. Peter