DC-30 sounded harsh tonite-Tubes or something else?

Discussion in 'Amps and Cabs' started by zekmoe, Sep 19, 2006.

  1. zekmoe

    zekmoe Member

    Messages:
    10,102
    Joined:
    Jan 27, 2004
    Location:
    Troy NY
    Playing thru my usually reliable Matchless Dc-30 tonite , and noticed the sound was unusually brite and harsh. Like a hard, SS breakup. No snap as usual. I haven't played this amp lately and have been favoring a couple of others, but I certainly didn't like the sound I was getting on any of the channels. Would you say, Powertubes, pre-amp tubes, both or something else would be the cuplrit. Hard to describe as it was plenty loud, but just cutting and stiff. Nothing like it used to be. Suggestions?
     
  2. oxtone

    oxtone Member

    Messages:
    4,779
    Joined:
    Sep 14, 2005
    Location:
    Edina, MN
    Always check the tubes first - that seems to solve alot of amp problems. If not them, then it's someting else, of course.

    Try tapping on the power tubes lightly with the amp on, and the volume low. If you hear a loud thump, then it's likely the tube. Also tap on the preamp tubes, if you can. If you hear a thump, it may be microphonic.

    I'm not a tech, but have used tube amps for 35 years. Good luck.

    Maybe you could call the guys at Matchless...
     
  3. illinimax

    illinimax Gold Supporting Member

    Messages:
    1,582
    Joined:
    Aug 17, 2002
    Location:
    Chicagoland
    The fact that both channels don't sound right suggests a problem with output tubes or rectifier tube(s).
     
  4. bluesmain

    bluesmain Member

    Messages:
    5,168
    Joined:
    Sep 5, 2006
    Location:
    Brandon, MS
    Remove all the tubes and then reinstall them (after they cool) lol .Sometimes that works for me when I have weird amp noises.
     
  5. teleamp

    teleamp Senior Member

    Messages:
    3,508
    Joined:
    Aug 22, 2006
    Location:
    Central Texas
    DC-30s sometimes go south, it's a write-off. pm me for my address, I'll pay shipping to take the bad amp off your hands.

    MikeY
     
  6. monstermike

    monstermike Member

    Messages:
    1,292
    Joined:
    May 31, 2005
    Was it at a gig, or at least a different room? I had a Chieftain that was hypersensitive to wall power differences...
     
  7. bluesmain

    bluesmain Member

    Messages:
    5,168
    Joined:
    Sep 5, 2006
    Location:
    Brandon, MS
    What rig are you using live ? :JAM

     
  8. bluesmain

    bluesmain Member

    Messages:
    5,168
    Joined:
    Sep 5, 2006
    Location:
    Brandon, MS
    Not that I have room for another amp :Spank

     
  9. Lasiurus

    Lasiurus Member

    Messages:
    22
    Joined:
    Aug 22, 2006
    Location:
    Burbank, CA
    i have an hc30 and ive been having the same exact issue, both channels sound very harsh and bright. =(
     
  10. riffmeister

    riffmeister Gold Supporting Member

    Messages:
    16,509
    Joined:
    Jan 4, 2003
    Location:
    near Philly
    right, that's what I was thinking, too.

    if it is not a tube problem, then probably it was lower than usual voltage from the AC outlet. lowering the voltage will make the amp less snappy and reduce clean headroom.
     
  11. zekmoe

    zekmoe Member

    Messages:
    10,102
    Joined:
    Jan 27, 2004
    Location:
    Troy NY
    I'll check the outlet voltage, but it's probably ok. We tend to have too much rather than not enough power at the plugs in my house.
    It's probably the tubes as suggested. Any good source for a full set? I may as well replace them all. It's been a couple of years, or longer on some.
     
  12. Lasiurus

    Lasiurus Member

    Messages:
    22
    Joined:
    Aug 22, 2006
    Location:
    Burbank, CA
    tried it and it worked! then replaced the power tubes this morning with a new set of jj. hc30 harshness gone. :)
     
  13. jspax7

    jspax7 Member

    Messages:
    2,232
    Joined:
    Dec 16, 2005
    Location:
    CA
    Check the line voltage with a power conditioner. (Furman) If it fluctuates or dips below 120 your tone will suffer as a result. A voltage regulator will keep things consistent. Every club is different.
     
  14. jspax7

    jspax7 Member

    Messages:
    2,232
    Joined:
    Dec 16, 2005
    Location:
    CA
    Line voltage at my home varies from 116 to 122. There is a big difference in tone when I see anything less than 120. JJ's may tame a bright amp, but without adequate voltage tone and dynamics will suffer.
     
  15. illinimax

    illinimax Gold Supporting Member

    Messages:
    1,582
    Joined:
    Aug 17, 2002
    Location:
    Chicagoland
    Nicely done! The JJs work great in this amp.
     
  16. zekmoe

    zekmoe Member

    Messages:
    10,102
    Joined:
    Jan 27, 2004
    Location:
    Troy NY
    Where's a good place to order these JJ tubes? I want to order a complete tubeset for this amp.
     
  17. zekmoe

    zekmoe Member

    Messages:
    10,102
    Joined:
    Jan 27, 2004
    Location:
    Troy NY
    I ordered most of the new tubes, except the ef86. The place I ordered from said that the sovteks dosn't sound good and the ones that do are expensive. They gave me a price of like $90 for one! Ouch. I did a search and found some even more. Like a Gold Lion or something like that for $150. I've always had some issue with those EF86's like pinging, but that seems like alot. Has anyone tried one of those higher end tubes in this amp?
     
  18. Killa-B

    Killa-B Member

    Messages:
    516
    Joined:
    Jul 13, 2005
    Location:
    Razorback Country
    I always liked the 5V4 rectifier tubes in my old DC-30. Seemed to sweeten the response. If the amp still sounds harsh, I recommend a telefunken ef86 and smooth plate 12ax7s. I had mine sounding very smooth with that tube compliment.
     
  19. Miles

    Miles Member

    Messages:
    3,975
    Joined:
    Aug 14, 2006
    Location:
    Colorado
    I know they're great amps, but the only one I played sounded harsh all of the time. I tweaked, turned, played differently, and it was still an ear piercing amplifier. Chances are, I played a bad apple, but it was full of custom expensive mods, and the geezer was just cocking his head loving the sound of it as I played. We all have different tastes in what sounds good.

    I only mention this because sometimes, we outgrow amps. It is possible, and it can happen. Our ears just aren't impressed by the sound as it may not be the right instrument for our creative direction or changes in your playing style. It just depends.

    Having said that, it probably has something to do with a pot needing biasing or worn tubes.

    Good luck.
     
  20. zekmoe

    zekmoe Member

    Messages:
    10,102
    Joined:
    Jan 27, 2004
    Location:
    Troy NY
    I agree Miles that our ear and taste changes. I'm liking my DrZ Maz18 since it's not as forward as my Matchless, even when it was sounding good. I'm wondering if I'm a candidate for a fancy channel switcher, like a Deziel? I've heard those can be smooth and even without being piercing.
     

Share This Page