DC-5 Dual Caliber Fuzz problem

[bjmccool]

Hey guys! I'm a newbie to this forum so please be gentle. I'm a guitar player of about 20 years now and my DC-5 is the first tube amp I've ever had the pleasure of owning. The problem is that I don't know much about it! I purchased it from a friend of mine about 2 years ago or so and have had no problems with it whatsoever.
What's happening is there is a fuzz (that's the best description I have) type sound coming out of it now. It's not there all the time, like when I'm not playing, or when it's on standby. It works the way it always did except now there is a fuzz on top of everything and it seems a little flat all around. I have replaced the power tubes with the same Sovtek tubes that were in it and it seems to have improved, but it's still there. It's not a speaker issue as I have tried it through a cabinet, and it's the same. I'm guessing that preamp tubes are the next step but I just wanted to throw this out there to some people who know something about this and get some advice on where to go next. Thank you in advance guys!!!

 

[cb101]

Hi bjmccool!

And welcome to the board! There a many posts and threads on this issue for all of the Mesa amps. Do a search on tubes and noise issues and have fun reading. I learn something new here everyday!

That being said: It sounds to me like a preamp tube issue. Most of the noise and fuzziness problems can be traced to the preamp tubes, assuming nothing is electrically wrong with the amp or power source. Get some new preamp tubes and start experimenting with them in various positions. There are some really experienced and brilliant people on this forum and I hope they will chime in. Check out some of the posts for Monsta-Tone, Chris McKinley, Charles Reeder etc.

Again, welcome to the world of Mesa!

 

[MrMarkIII]

It's usually best to replace pre-amp tubes one at a time in order to isolate the problem. If you just pull and replace all the tubes at once, you may actually fix the problem, but if it reoccurs you'll be buying another complete set to fix the problem a second time.

 

[bjmccool]

Okay cool, thanks guys! I've done a few searches on the subject and it seems that the preamp tubes may indeed be the culprit. Now, are the preamp tubes all the same? Or do they all have different values? I understand that each one has a specific purpose, but am not sure if they are all the same tube. I have to apologize for my lack of knowledge, but I've just never had to venture down this road before! That being said, I'm finding it all very interesting and am looking forward to experimenting once I understand a little more! Thanks again for the help!

 

[MrMarkIII]

Some light reading:
http://www.mesaboogie.com/manuals/Dual%20Cal%20DC-5.pdf
(The owner's manual)
Welcome to the club!

 

[edward]

Hi bmj ...welcome!!!

Huge +1 on reading through the manual ...some very good info there.

Of your preamp tubes, the V1 is the most critical in terms of noise floor. Also go at each preamp tube position one by one, as advised: more time consuming, but the right way to determine what does/doesn't need replacing.

You could easily get a Mesa tube and be done with it. Or you can experiment with a variety of other tubes ...lots there in terms of +/-- but it's another way of "fine tuning" the tone to you liking. The design of the DC5 is such that specific tubes are dedicated to specifics of each given channel, so should you want to experiment with tone, say, only ch1 but leave ch 2 alone, you can do that, vice versa, or swap tubes that affect the amp globally.

Check out the archives ...lots there to read and weigh opinions. To be sure, if you want to just replace with Mesa stock to get her back to square one, that's good too. But if you'd like to try the former, I've used http://www.kcanostubes.com for a while now. No affiliation other than being a very satisfied customer. Mike is also a frequent contributer at TheGearPage, and is very well respected there, FWIW. And I found that in doing so (with some experimentation, remember) I ended up with a DC5 that is "custom" tailored to fit my tone and style perfectly; she's a keeper to be sure! ...Just some food for thought

Edward

 

[bjmccool]

Thanks so much guys, you've really been helpful. I can't tell you how much I appreciate this. I don't know alot of people around here who I trust enough to mess around with my Mesa so this has been great! I'm gonna do a little reading and I'll let you all know how I make out Thanks again!!!

 

[Monsta-Tone]

Welcome, great choice & +1,000 to everything that has been said already.

Change them 1 at a time to find the culprit. I usually lay my combo on it's face on the floor so that I can see the tube sockets more easily. I also remove the wood panel and metal bar across the back.

Be gentle when swapping tubes. The sockets or tube pins can be damaged otherwise.

If it's a head, turn it upside down on a rug or towel. This will let you see the tube sockets more easily. I'm pretty sure that I had to remove the power tubes on my DC-5 when it was a head too.



The manual is a great place to start understanding your amp. There is a lot of good information in it.