1. Please take 30 seconds to register your free account to remove most ads, post topics, make friends, earn reward points at our store, and more!  

Looking for advice on an ampeg SVT 4 pro

Discussion in 'Amps and Cabs [BG]' started by wolfkeller, Sep 11, 2016.


  1. wolfkeller

    wolfkeller Supporting Member

    Aug 11, 2013
    detroit
    I just picked up a USA svt4p. I didn't get alot of time to play it as all my gear is in a trailer and I had a gig sat. So, I ran it onto 2 svt 810e cabs on stereo obviously. I have to say, it just didn't seem to be very loud. I have read about bass sucking power, I was mindful of that but it really sounded weak unless I used the ultra bass. I had the gain nearly maxed and the master at noon to get a decent level. Mind you, I play on a loud band with a very hard hitting drummer and no, theyre not gna turn down lol. I don't even bother with monitors since they usually screw it up.

    So, I like a good drive and a nice thick tone, I play a variety of basses but it was IMO, weak. I just came from using 2 GK 800rb and they sounded better at 300w each.

    My first thought is the preamp tubes. Maybe a new set with something more suited to overdrive? I need this thing loud and powerful and not sure how to proceed. Appreciate any input.
     
  2. wolfkeller

    wolfkeller Supporting Member

    Aug 11, 2013
    detroit
    I should add that I ended up putting my BDDI into before we went on as it just wasn't cutting it
     
  3. Arthur U. Poon

    Arthur U. Poon

    Jan 30, 2004
    SLC, Utah -USA-
    Endorsing Artist: Mike Lull Custom Basses
    I owned a 4-Pro for a bit, but I ran mine bridged into a pair of 4-10's. I absolutely loved it's sound, but I couldn't make it loud enough, either. I don't think I ever tried the Ultra Lo switch.

    I've read a couple of SVT4-Pro threads here, where the same lack of volume concerns are stated , and there's longtime 4-Pro owners who shed light on how they set the preamp gain and how to eq the amp to get the most out of it.

    Google SVT4-Pro lacks volume. I think you should be able to find the threads I'm talking about. I wouldn't change your preamp tubes until you read through the threads.

    Take care.
     
    wolfkeller likes this.
  4. JimmyM

    JimmyM Supporting Member

    Apr 11, 2005
    Apopka, FL
    Endorsing: Ampeg Amps, EMG Pickups
    What were your gain and master set at? Turn the gain up to as far as it can go before distortion. Last time I used a 4 Pro, it was with a PJ and I had the gain at somewhere around 3:00 and it wasn't distorting and it was blasting the 810e pretty darn good. Of course, I can't use it with the band at that volume, but I darn sure tried it at soundcheck!
     
  5. See that "Peak" light? Stick a piece of black electrical tape over it and forget it is there.
     
  6. wolfkeller

    wolfkeller Supporting Member

    Aug 11, 2013
    detroit
    I had the gain at near full and the master about 12. I has a solid red light on gain and I was seeing yellow on master
     
  7. BasturdBlaster

    BasturdBlaster Supporting Member

    Feb 19, 2012
    Crandon WI
    Mine needs the gain at least at 3 o'clock and I would say the master needs to go past noon for serious volume. New preamp tubes wont bring more "heft", I already tried that with mine, hehe:D
     
  8. What kind of EQ were you using? With two 4 Ohm cabs you have 490 watts on each side of your amp.
     
  9. wolfkeller

    wolfkeller Supporting Member

    Aug 11, 2013
    detroit
    Well, I had the graphic off. I'm gna pull it out later and get a pic of how it was set
     
  10. beans-on-toast

    beans-on-toast Supporting Member

    Aug 7, 2008
    It's an old amp and needs to be checked out by a tech to ensure that it is preforming to spec.. Low volume is not normal.

    In particular, have them check the power supply voltages and caps, the tubes, the power tube bias. The tube sockets and jacks contacts should be cleaned (with Deoxit), especially the shunts in the effect send and receive jacks. This is all basic maintenance.
     
    Last edited: Sep 12, 2016
    Bass 45 likes this.
  11. wolfkeller

    wolfkeller Supporting Member

    Aug 11, 2013
    detroit
    I will probably do that, but this is a 4pro, no power tubes or sockets
     
  12. beans-on-toast

    beans-on-toast Supporting Member

    Aug 7, 2008
    Oops. I should know better.

    The power transistor bias should still be checked to optimize performance and cleaning the jacks is very important. An oxidized jack contact in the signal pathway is like putting a resistor inline. It reduces the signal and prevents the amp from putting out the power that it should. Likewise for checking out the power supply.

    Here is a link to the 4Pro schematics. It can help to have a set if your tech doesn't have a copy.

    Ampeg SVT 4 Pro schematic needed
     
    Bass 45 likes this.
  13. wolfkeller

    wolfkeller Supporting Member

    Aug 11, 2013
    detroit
    Highly appreciate it!
     
  14. mpdd

    mpdd neoconceptualist

    Mar 24, 2010
    LA
    I've only experienced these twice, but in each time they were brutally loud, therefore I'm perplexed about this issue coming up again and again
     
  15. spaz21387

    spaz21387

    Feb 25, 2008
    Portland oregon
    I think thats common with 4 pros. I have tried 3 different ones and all 3 didnt have enough volume even though i was running them into an 8x10... my 8x10 and a v4b or svt is insanely loud. I tend to stay away from any ss or hybrid ampegs. I love their all tube amps though.
     
  16. wolfkeller

    wolfkeller Supporting Member

    Aug 11, 2013
    detroit
    Here is how it was sat. The ultra high and low are on as it sounded crappy otherwise. The limiter defeat is engaged as well. IMG_20160912_152742808.jpg
     
  17. JimmyM

    JimmyM Supporting Member

    Apr 11, 2005
    Apopka, FL
    Endorsing: Ampeg Amps, EMG Pickups
    Not near enough gain. Crank that puppy! With a Precision I have to crank to like 4:00 before I start hearing distortion. That's your problem...unused potential.
     
  18. Ditch the ultra High and Low. That is just scooping your mids. Turn the GEQ off. Turn your mid selector down to 1. Turn the gain up. After you get your volume sorted, you can turn the GEQ back on to adjust the final tonal changes.


    Yep, turn that sumbitch up.
     
  19. Hoss Groovealot

    Hoss Groovealot

    Jun 12, 2015
    I have an issue where my master is 12:00 and higher to get good volume too. It seems like it should be that loud at much lower knob positions. Also, try backing that compressor down. On mine that knob really cuts my volume.
     
  20. wolfkeller

    wolfkeller Supporting Member

    Aug 11, 2013
    detroit
    I killed the graphic cranked the gain and killed the ultra low, waaay too fuzzy and I LIKE gain!
     

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.