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ampeg 2010 svt heritage

Discussion in 'Amps and Cabs [BG]' started by juggernaut1, Dec 21, 2014.

  1. Dec 21, 2014 #1
    juggernaut1

    juggernaut1

    Jul 5, 2007
    Maryland
    FYI for SVT heritage owners.
    My 2010 svt heritage #005 broke down, goes into fault mode. Searching the net, I found this thread on another site.

    http://music-electronics-forum.com/t38027/

    Quote from Ampeg's Hodgy:
    "Hmmm, this one was from the first year's production run in 2010 (before I got my dirty mitts on them). Looks like there's an ECO from April 2011 that states "AMPEG SVT - Harmonize all screen resistors", so I'm guessing that's where the change happened. What's really bizarre, is that the TSB to change those resistors from 22 to 220 came out in June of 2001. I can neither confirm nor deny that someone was napping on their desk when revisiting the BOM for the Heritage line."

    The cause of failure from the thread was this:
    "6550 glass fracture from hold-down clamp spring, arc'd, blew screen resistor
    After spending the time to drill out the broken screw on the AC Mains PCB assy, re-threading the standoff to accept a shorter screw, I inspected the 6 power tubes, wondering if I'd find a crack in any of the 6550's. Sure enough, one of tubes had a small crack all the way thru the glass, just above the chipped surface from direct contact with the late-generation stiff hold-down clamps' spring/clamp joint. 3 of the six tubes had noticable surface abrasions from those clamp spring joints. I set the amp up on end, giving access to the cathode resistors for checking the individual currents. Here, I started with one pair at a time, first biasing up for 24mA per tube. Having marked the suspect tube, I left that one for last. Four of the tubes were all within a couple mA of the setting established for 24mA. Fifth tube read 10mA higher, at 34mA. Set that one aside, and then put the suspect tube into place."
     
    Last edited: Dec 21, 2014
  2. Dec 21, 2014 #2
    JimmyM

    JimmyM Supporting Member

    Apr 11, 2005
    Apopka, FL
    Endorsing: Yamaha, Ampeg, Line 6, EMG
    Well here's the good news: Ampeg now sells low profile power tube clamps that are much better:

    2013HeritageSVT-CL_zps5c97cd3d.jpg

    This is my 2013 Heritage SVT-CL, the very first one made using those clamps. They are now stock on the Heritage, and they retrofit any SVT-CL, 2 Pro, or VR with the big clunky spring retainers pretty easily:



    Contact Ampeg's service dept. at 1-800-898-3211 or [email protected] if you're interested, and I can't think of any reason not to be interested. They're a million times better than the spring retainers.
     
    juggernaut1 likes this.
  3. Dec 26, 2014 #3
    Bluzeman90

    Bluzeman90

    Jan 24, 2013
    St. Louis, MO
    Those are sweet! I got my heritage last November and it's got the springs. #85. Kinda wish they had already switched over :sorry:
     
  4. Dec 26, 2014 #4
    JimmyM

    JimmyM Supporting Member

    Apr 11, 2005
    Apopka, FL
    Endorsing: Yamaha, Ampeg, Line 6, EMG
    If I had one with the springs, I'd be on the horn with Ampeg yesterday getting the new clamps.
     
  5. Dec 26, 2014 #5
    Bluzeman90

    Bluzeman90

    Jan 24, 2013
    St. Louis, MO
    They're closed till the second of January, but I already sent an email. I just really hope it doesn't cost anything:unsure:. thanks for the info though, Jimmym; hope they respond quickly and in my favor
     
  6. Dec 26, 2014 #6
    Mastermold

    Mastermold

    May 5, 2008
    Orange County, California
    I may get them someday but the old springs work just fine in mine and "if it ain't broke" etc.. But thanks for posting this, will definitely keep in mind for the future.
     
    Last edited: Dec 28, 2014
  7. Dec 27, 2014 #7
    beans-on-toast

    beans-on-toast

    Aug 7, 2008
    Vintage amps had a 22 ohm screen resistor. The modern SVT's use 220 ohm. It helps the 6550 tubes operate in a way which helps with tube life. Could be why they made the change on the Heritage CL amps.

    The spring retainers can be hard on some tubes. Adding some high temp silicone rubber tubing over the springs can help be preventing them from running on the glass envelope and damaging the tubes.
     
    Last edited: Jan 24, 2015
    juggernaut1 likes this.
  8. Dec 30, 2014 #8
    juggernaut1

    juggernaut1

    Jul 5, 2007
    Maryland
    Thanks Jimmy. I'll get the clamps. The amp is at ProTech in Silver Spring MD now. I'll post the cause of breakdown when I find out what it is.
     
    JimmyM likes this.
  9. Feb 18, 2015 #9
    Phantomfears

    Phantomfears

    Apr 1, 2012
    Seattle
    I believe I am having the same or similar problem with my Heritage SVT as the fault light stays on and I have the springs. Mine only has about 3 hours of playing time. I took it to the authorized Ampeg service center here in a Seattle (American Music) and am waiting to hear from them. I'll post what they advise when I hear back. Juggernaut, did you find out what the issue was with yours?
     
  10. Feb 18, 2015 #10
    beans-on-toast

    beans-on-toast

    Aug 7, 2008
    Those are very nice clamps for amps. Similar ones, made by Birtcher, were used in the vintage SVT's. I wish that all tube amps came equipped with them.
     
    Last edited: Feb 18, 2015
  11. Feb 18, 2015 #11
    juggernaut1

    juggernaut1

    Jul 5, 2007
    Maryland
    Power tube failure was the culprit. They replaced 8 resistors with 220 ohm FP resistors. Performed TIB0003 and a polyswitch replacement bulletin. Receipt also says that they re-flowed solder.
    Next step is to get the clamps. Good luck with yours Bassman5001.

     
  12. Feb 18, 2015 #12
    Phantomfears

    Phantomfears

    Apr 1, 2012
    Seattle
    Thanks for letting me know. Was this covered by warranty?
     
  13. Feb 19, 2015 #13
    juggernaut1

    juggernaut1

    Jul 5, 2007
    Maryland
    Yes, everything was covered by warranty except for the tubes of course.