peavey vmp2 tube switch / upgrade

Discussion in 'Preamps / Channel Strips' started by mikE@THECAVE, May 24, 2004.

  1. Skeetch

    Skeetch Guest

    Bought mine used so it's got whatever tubes came stock with it probably. Haven't cracked it open yet so I'm not sure. I've got some Ruby's, Sovtek's and some GT's lying around that I figured I'd experiment with. Haven't gotten around to it yet but I'm kinda getting the itch to try it.

    Pretty hard to go wrong with Mullard's and Telefunken's. Thing is, there's more to tube pre's than the tubes. Lots of other stuff in front of and behind the tubes that all have an impact on the sound and performance. IIRC, Jim's mod swaps a number of the caps to film versions to make the pre "faster" - basically it responds quicker to incoming signals I think. So just changing the tubes may not have a big impact on how the thing sounds. Just guessing here, though, since I've not tried it yet.
  2. mikE@THECAVE

    mikE@THECAVE Guest

    I've talked to Jim and he said its alot clearer with the mod .And thats before you turn up the high Eq.--Also i found out on the Net that the 1/4 in. outputs bypass the output transformer and give you a much better signal.Dont close it up in a rack cause it gets to hot .I heard one caught fire.
    You probably have the china tubes in yours,thats what mine has in it.Are you gunna have the MOD done .Why dont you go for it???I cant see that id ever sell it even without the mod.Ill bet with the Mod it would be like a 3000$ unit
  3. Skeetch

    Skeetch Guest

    Cash availability is on the short side right now or I probably would do the mod. As I mentioned earlier, Jim mod'd my Masterlink and it's a whole new machine. Sounds incredible. Use it for two-track mixdowns at 24/96 off my board and it's just amazing.

    I've got my VMP racked but it's got 2U worth of space above and below it and the rack is well vented. It does indeed get toasty but I've not had any problems with it over heating. This thread has definitely got me interested in trying some different tubes though. Got a session later today and if I've got some time I might throw the Ruby's in for grins.
  4. mikE@THECAVE

    mikE@THECAVE Guest

    Just wondering --what did jim do to your masterlink and what model does he upgrade.Can i get an older model with the same sound quality.I was thinking of getting one for the same 96k mixdown.
    Let me know what the tube change does for the sound.Is one tube for input one for high eq -one for low eq and one for output.Is that the way it works.
  5. Skeetch

    Skeetch Guest

    Not sure if this is what you meant, but there's no tubes in the Masterlinks. Jim's Masterlink mod improves the A/D conversion on the units pretty significantly by replacing certain components with better quality ones. Specifically, here's what Jim does the the ML's:

    - install National LM6172 dual opamps at 3000/us slew rate.

    - install larger Rubycon Z series electrolytic caps to extend the low end (and did it ever!!)

    - install .01 uf wima poly caps on the input, MIT's on the output.

    - increased the power supply bypass caps and installed .1 uf mono ceramic bypasses.

    - Bandwidth limiting caps were used on certain stages.

    - The opamps used as followers were cut and changed to closed loop buffers.

    The mod is $200.00 (plush shipping to and from Audio Upgrades). I believe it can be done to any ML but I'd recommend you verify that with Jim.
  6. mikE@THECAVE

    mikE@THECAVE Guest

    boy that sound like a cool upgrade.Let me know if you get the vmp2 sounding better with some new tubes

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice