Reverb buzz in Mesa Blue Angel

Discussion in 'Amps and Cabs' started by Mincer, Feb 8, 2008.


  1. Mincer

    Mincer Member

    Messages:
    3,231
    Joined:
    Nov 25, 2006
    Location:
    Tampa Bay area, FL USA
    I have a Mesa Blue Angel- for those that don't know, this was an interesting non-MV amp from the 90s...2 sets of power tubes, 2 6v6s, and 4 EL84s, which can be used separately or together. Mostly I use it on the 6v6 setting.

    Lately, when the reverb is turned on, I get a progressively louder buzz as it is turned up. The reverb is still working, just with this hum alongside it.

    My Blue Angel is silent when the reverb is at 0, turn it up and there is a noticable buzz/hum. When it happens, it is on any power tube setting, at any volume. The ground switch doesn't fix it. The guitar signal is amplified as always, with this added hum which gets louder as I turn the reverb up. In fact, if I turn the volume to 0, the buzz from the reverb still comes through, as long as the reverb is on anything but 0.

    I need reverb. Especially the reverb on this amp, it rocks. Well, I switched out every preamp tube, including the reverb driver and reverb mix, with several sets. Same result. This didn't always happen, in fact, the amp was fine for several years- this is pretty recent.
    This happens even with no guitar plugged in. So, what can I check next? Anyone with the same experience? What to check next?
     
  2. billy11

    billy11 Member

    Messages:
    3
    Joined:
    Jan 17, 2008
    Location:
    Pacific Northwest
    Hi Mincer,

    I would start by swapping or replacing the 12ax7 that runs the reverb which I think is V3, but check the blue prints here;

    http://www.tubefreak.com/mesa.htm#angel

    Hope that helps.
    Billy11
     
  3. mild

    mild Member

    Messages:
    2,117
    Joined:
    May 11, 2006
    Location:
    Bottom of the World
    OP says he swapped the reverb driver tube.

    Could be a bad connection to the reverb tank/springs itself? If its not the tube, then that certainly narrows it down. You're more than likely going to need to take it to an amp tech, that's what I'd be doing in your shoes. Good luck!
     
  4. dumeril7

    dumeril7 Member

    Messages:
    177
    Joined:
    Jul 23, 2003
    Location:
    Austin, TX
    Yeah, I would make sure those cables to/from the reverb tank are in good shape and the connections are solid. I had a Blue Angel head that was somewhat prone to having the reverb cables pulled when I stuffed the power cable into the back. Beyond that, and since the reverb driver tube is clearly not the issue, I think you'll have to take it to a tech....

    D7
     
  5. Mincer

    Mincer Member

    Messages:
    3,231
    Joined:
    Nov 25, 2006
    Location:
    Tampa Bay area, FL USA
    Funny, if I unplug the reverb tank, the buzz still comes through when the reverb knob is up. It is quieter through the amp itself, and louder through the 'slave out' jack in the back.
     
  6. Miles

    Miles Member

    Messages:
    3,974
    Joined:
    Aug 14, 2006
    Location:
    Colorado
    Dude, I have the same thing, I swapped V3 and everything, it's just part of the beast. The blue angel is anything but its name. It's actually a moody succubus that takes the piss out of your playing.

    Having said that, I love the tubby tone it has with just about any guitar, and I will probably end up buried with mine. Some people hate the 'honk' it has with OD/FUZZ pedals, but I really like it. It cuts through the way I want it to.

    So, yeah, I live with that buzz. It shouldn't be too bad though, it should only be pretty minor, but noticeable.

    I've never been bothered by things like 60 cycle hum and such, just a waste of time. I love records that have amp hum on them. It makes it sound more believable to me.

    I love my blue angel.
     
  7. myles111

    myles111 Member

    Messages:
    2,955
    Joined:
    Nov 19, 2003
    Location:
    Los Angeles CA

    It sounds like you are talking about the head and not the combo? This is very common in the heads as the reverb tank is so close to the transformers that hum is a natural end result. If you think it was fine for years you may have just become less tolerant as it is always there with the reverb to any usable level in the head version of the amp.

    Short of pricy mu-metal shielding there is little that can be done. Just the nature of the amp.

    Don't forget that turning the mid control past 10:00 or so adds more gain to the amp and this will make that reverb issue more noticible.


    [​IMG]
     
  8. Mincer

    Mincer Member

    Messages:
    3,231
    Joined:
    Nov 25, 2006
    Location:
    Tampa Bay area, FL USA
    Actually, this is the 1x12 combo...and this just satrted happening a week or so ago. If I turn the reverb off via the footswitch, the buzz goes away.
     
  9. myles111

    myles111 Member

    Messages:
    2,955
    Joined:
    Nov 19, 2003
    Location:
    Los Angeles CA
    Get the amp to a good tech.
     
  10. Miles

    Miles Member

    Messages:
    3,974
    Joined:
    Aug 14, 2006
    Location:
    Colorado
    I also have the 1x12 combo and again, same thing. The blue angel is everything except a pristine polished sound. It runs loud, it hisses, it honks, etc.... It's not a super quiet amp that you would tour with Michael Bolton with. It's kind of a swampy blues grind that you bang blues or rock chords or leads on. Look at some of the famous players that use this amp, they are not soft pickers...generally.
     
  11. Mincer

    Mincer Member

    Messages:
    3,231
    Joined:
    Nov 25, 2006
    Location:
    Tampa Bay area, FL USA
    Strange, because I am...I play softly, and let the amp do all the work- I don't really bang on it at all- the band is more of a jazzy blues band. Anyway, the problem being is that it isn't inherent in the amp, it just started doing this.
    If I use the footswitch to switch out the reverb, the humming stops.
     
  12. chaz

    chaz Member

    Messages:
    1,560
    Joined:
    Jan 11, 2005
    Location:
    Wisconsin
    Maybe it's actually an issue with the footswich? Does it make noise with the footswitch disconnected?
     
  13. Mincer

    Mincer Member

    Messages:
    3,231
    Joined:
    Nov 25, 2006
    Location:
    Tampa Bay area, FL USA
    Yeah, even without the footswitch. Someone I know might have an identical reverb pan, which I may try...my guess is that is one of the next steps.
     
  14. The Whiz

    The Whiz Member

    Messages:
    4,742
    Joined:
    Mar 18, 2004
    Location:
    5 7 5
    My blue angel did that until I realized that the strap in the bottom of the combo that holds the tank in place was restricting the movement of the tank while in operation, so I just pulled it out from under the strap. The other thing I did which really improved it was replaced V3 and V4 (reverb send and reverb return/effects loops IIRC) with 12at7's.

    Way better. The reverb is no noisier than the rest of the amp. Another way to clean up the amp's tone is putting a lower gain tube in V2 (not V1, John Phillips can explain this better than I). I had a GE 5751 in there and it was very nice and the amp's background noise was reduced.
     
  15. The Whiz

    The Whiz Member

    Messages:
    4,742
    Joined:
    Mar 18, 2004
    Location:
    5 7 5
    bumping this

    Mincer, did you try replacing the 12ax7 in v3 with a 12at7?
     
  16. smallcrap

    smallcrap Member

    Messages:
    332
    Joined:
    May 17, 2005
    Hey Mincer, how did you make out with this problem?

    I have the exact same problem, that seems to have developed recently. Extremely loud buzzing (not normal mesa/gain associated hiss that changes with volume or other EQ...) that is completely isolated/controlled by the reverb knob alone; reverb at zero, noise is gone.

    I tugged at the reverb wires and pulled out the tank completely and found nothing weird. I'm not a tech though, so outside of hanging, broken wires or a dead mouse, I wouldn't know what to look for.

    I'm going to try to change some of the preamp tubes as noted in other posts/threads and see what that does.
     
  17. Mincer

    Mincer Member

    Messages:
    3,231
    Joined:
    Nov 25, 2006
    Location:
    Tampa Bay area, FL USA
    no i hadnt done this...how would that change the sound of the reverb? i did eventually replace the tank, which cut the noise in half...it is still there, just not so loud. Official word from Boogie: the reverb buzzes...not the answer i wanted.
     
  18. smallcrap

    smallcrap Member

    Messages:
    332
    Joined:
    May 17, 2005
    What kind of tank did you replace with and how much did it cost?

    I have another question for John Phillips and/or other Blue Angle owners; do the tubes sockets run left to right V1-V5 or vice versa. Mesas have had it both ways among models and it's not in my manual or the one on Mesa's site.
     
  19. Mincer

    Mincer Member

    Messages:
    3,231
    Joined:
    Nov 25, 2006
    Location:
    Tampa Bay area, FL USA
    i used the exact same accutronics unit that came with it...bought it on ebay for about $30US. the newer one has about 1/2 of the hum as the old one...its still there, but unless you have a good mic right against the speaker and listen to the amp in isolation, you don't hear it...live you certainly dont. as far as tubes, i think there is a sticker inside the chassis..the amp is at rehearsal, so i can't verify. i had replaced all of my tubes with the Eurotube kit, but it didn't make a difference in the hum from the reverb...also, my tube kit had 3 bad tubes in it- not to trash Eurotubes, but it was my experience.
     
  20. smallcrap

    smallcrap Member

    Messages:
    332
    Joined:
    May 17, 2005
    Thought I'd post an update for anyone who may also run into this. Mine ended up being the reverb tank also. I finally got around to swapping it with the one (same accutronics model #) in my Subway Blues and sure enough that was it. I also made sure to test and rule out the cables as well.

    This is not hard to do, we're talking about 5 or so screws and maybe some pliers to pull of those stubborn metal rca style plugs.

    So for 24 bucks my new tank is on the way.
     

Share This Page