Roadster cracklingpopping in all channels

[Skanabanugan]

Hey just bought my roadster a couple weeks ago off craigslist so I don't know how long this problem has been going on. I have recently been using the effects loop and the channel switcher pedal and noticed that every channel crackles and pops even when no guitar cables are plugged in nor cables in the back besides speaker cable. I have tried changing all the preamp and power tube and it's still there(not talking about the pop when changing channels). But the crackles and pops go completely away when the switch on the back labeled hard bypass loop,solo and output controls is turned on instead of flipping it down so the loop is on. Is the loop dirty(weird since it still makes the crackling/popping without cables in the send/return)? solo or output pots shot? I have no idea and I need the loop for all my delays they sound like crap in front of the amp. Any help would be appreciated.Also does anyone have a schematic for the pre-amp tube layout I can't find one anywhere and don't see it on the amp like the manual states. Thanks _Shane

 

[domct203]

Congrats on your new Roadster and Welcome to The Boogie Board.

The pre-amp tube layout is the same as the RKII. V1 is the preamp tube closest to the input jack. There should be a metal plaque inside the headshell (or combo) that shows the tube layout. It's black and blends in with the shell so you have to really look for it, use a flashlight.

If the crackling goes away when you hard bypass the loop, concentrate on the FX loop jacks and / or the V5 tube. Clean the jacks with a good quality cleaner like DeOxit. Even without anything plugged into the loop, the jacks have contacts in them that complete the circuit when there is nothing plugged in.

If that doesn't help you may need to clean the tube socket for V5, or less likely, the FK loop send pot.

(is this your first tube amp?)

Hope this helps.

Dom

 

[Skanabanugan]

Hey thx for the reply! This my third tube amp I have a 6505 head(before that had a 5150 combo). Yeah Ill have to try the contact cleaner but have noticed it actually makes the crackling/popping when the loop is hard bypassed to. Guess that's the only option left before I bring it in to boogie because I've changed the power tubes and preamp tubes with good ones and the same thing still happens. I see If i can find that tube schematic also. Also since I'm miced and can't crank it is it better to run the individual channel masters higher or the master higher.Thx-Shane

 

[domct203]

You can download the RKII manual from Mesaboogie.com.

As far as output vs masters IMO try to get the channel masters to at least 9:39-10:00 and use the output for final volume. I would also use the 50W settings, tube rectified, spongy power settings first and see if that gives you the tones you are after. This will allow you to crank the output a little more with reasonable volume.

Dom

 

[Skanabanugan]

Cool thx for the tips.-shane

 

[cheameup]

Is it on every channel ? I find I get odd crackles and pops on my 3 channel DR clean channel at very, very low volumes . never happens at a decent level

 

[Skanabanugan]

Yea it's on every channel and I had the master at 12 o'clock to yesterday and was still doing it. I don't really notice it when I play but because Im miced @ church I can't have it popping/cracking when Im not playing especially since the only way to stop it it is to put it back in standby. _Shane

 

[domct203]

Yea it's on every channel and I had the master at 12 o'clock to yesterday and was still doing it. I don't really notice it when I play but because Im miced @ church I can't have it popping/cracking when Im not playing especially since the only way to stop it it is to put it back in standby. _Shane

If the popping/crackling is still happening even when using the mute function of the footswitch the problem is in the output (power) section for sure. does it do it in the 50W setting? If so, swap the inner and outer pairs of power tubes and see if it continues in the 50W setting. You may just have a bad power tube.

Dom

 

[Skanabanugan]

First off thx for your continued help. Actually I didn't think of trying the tuner mute button but tried it and it eliminates the crackling/popping. Tried the 50w mode and still there plus I already switched out the tubes with other ones I had from my 5150 that work fine in that head. Weird because when I play it sounds fine, maybe because its so loud I can't here the popping/crackling but once I stop its there(second thought yea its cause the playing drowns it out.) thx-Shane

 

[Skanabanugan]

Bummer so I tried deoxit in every jack on the roadster and cab let it dry and still has the crackling/popping.

 

[Metaghius]

the same thing happened to my triple rectifier and the Mesa tech had to replace 6 of the J175 FET's, very cheap items 2-3 dollars each...could be similar to my problem...

 

[Skanabanugan]

Dropped my roadster off @ mesa boogie Hollywood and they fixed my problem :mrgreen: Apparently they had to replace 120k resistor in the v5 b circuit. Works awesome now just hope nothing else weird pops up. The guy said that they very rarely encounter the problem I had.