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idea.. using 2 amps for more power

Discussion in 'Amps and Cabs [BG]' started by a e i o u, Nov 10, 2003.


  1. ok. i had an idea. can i use both of my heads to make more overall power?

    i have:
    ampeg b2r 200w@8ohms 350w @4ohms
    peavey sessionbass 130w@8ohms 200w@4ohms

    they both have the whole pre amp input deal that i know next to nothing about, but i was thinking...maybe if there was a way to hook them up together to get a big wattage by using the pre+power amp of the ampeg, and also usign just the poweramp of the peavey? or am i total out of left field on this?
     
  2. Johnny BoomBoom

    Johnny BoomBoom Supporting Member

    Jun 8, 2001
    Glasgow, Scotland
    I think you'd find that if you tried to take the output of ampeg out inot the input for the poweramp, you'd be liable to blow something to pieces.

    Remember if you try it to get a friend to do it, stand well back, and let us know the results!:eek:
     
  3. wulf

    wulf

    Apr 11, 2002
    Oxford, UK
    I think Mr BoomBoom is right - amps are rated to give X amount of gain... but I think you'll also find that they are rated to recieve an input signal in a specified range as well.

    You could get more volume by running the two power amps in parallel (splitting the signal and driving two sets of cabinets) but if you try to run them in parallel, you're likely to end up with at least one broken amp, a fused power circuit and possibly a neat (but expensive and short lived) pyrotechnic display.

    I wouldn't risk it...

    Wulf
     
  4. BillyB_from_LZ

    BillyB_from_LZ Supporting Member

    Sep 7, 2000
    Chicago
    Geezzz guys, where's your sense of adventure?;)

    I looked at the owner's manuals for both amps on-line and came up with a few ideas....

    Make sure you keep the master volume controls of each amp (Master on the Ampeg, Volume on the Peavey) turned down when moving cables around.


    Idea 1 - Plug your bass into the Session bass and run an instrument cable from the Tuner Send Jack (Item 3 on page 4 of the manual) to the Input of the Ampeg (Item 1 on page 4 of the Ampeg's manual). The tuner output is an instrument level signal (no gain problems) and is buffered from the rest of the amp.

    Doing this you can use the EQ of both amps to dial in their respective cabinets.

    Idea 2 - Plug your bass into the Ampeg head run an instrument cable from the Effects send of the Ampeg to the Effects Return of the Peavey. As far as I can tell, both are designed to work at instrument level so there should be no gain issues there either.

    Doing this will allow the Ampeg preamp to control the tone of both speaker systems.

    As far as I can tell, the output volume controls on both amps (Master on the Ampeg, Volume on the Peavey) are located after the effects return. You should be able to use these two controls to balance the volume between them.

    Try interconnecting your amps both ways and see what works best.

    Please let us/me know how it works out...

    Have fun!!!!
     
  5. Johnny BoomBoom

    Johnny BoomBoom Supporting Member

    Jun 8, 2001
    Glasgow, Scotland

    Right, I picked up that our thread starter was looking to try to sneakily boost lots of power. And I think I have led wulf to that conclusion too.

    Maybe our thread starter can clarify his idea a bit further!

    What you are suggesting will more than likely work - you are just using the second amp as a slave amp! All sorts of people do that from time to time. If you have 2 amps, you might even have a pedal with stereo outputs and be able to do it that way!

    My concern was that an output from one amp - in 10s or 100s of watts was about to be plugged into an amp that is barely capable of generating that much power on it's own, and immediately saw health and safety implications:)

    a e i o u - can you clarify your idea please?
     
  6. xyllion

    xyllion Commercial User

    Jan 14, 2003
    San Jose, CA, USA
    Owner, Looperlative Audio Products
    If you are talking about using two amps that are powering two different cabs, then it is possible to take the preamp output of one and feed the power amp input of the other.

    If you are talking about taking the two power amps and trying to drive a single cabinet with them both at the same time, then the answer is NO, DEFINITELY NOT!
     
  7. No idea about the Peavey, but the B2R has both preamp outs and power amp ins that I have used. You can use it as a slave, or to drive a slave.

    If you have two cabs though, why wouldn't you just run the B2R at 4 ohms? That would produce about the equivalent amount of power wouldn't it? :confused:
     
  8. BillyB_from_LZ

    BillyB_from_LZ Supporting Member

    Sep 7, 2000
    Chicago
    The Peavey only has an effects loop. That's why I suggested the interconnection scheme that I did.

    I reread a e i o u's post and while you could read it that he wants to connect the amps together in an unsafe manner, I didn't think that that was what he meant. Once we get a clarification, we'll know for sure.

    If he used 4 ohm cabinets with both amps (in another thread he was talking about buying a 4 ohm Ampeg 4x10 IIRC) then he'd get maximum power from each.
     
  9. BillyB_from_LZ

    BillyB_from_LZ Supporting Member

    Sep 7, 2000
    Chicago
    Forgot to mention...I owned an SVT-350H, the head version of the B2R. One time I was bored and decided to take an output from the 350H's DI (switched to pre EQ) through a microphone impedance matching transformer into the front end of a 50 watt Marshall stack (with two 4x12s). The signal that the Marshall saw was fine (instrument level). I came to the conclusion that that Marshall didn't make a very good bass amp...it was thrashy though and the combo of the Marshall and my SVT350H/Ampeg 8x10 sounded pretty evil.
     
  10. wulf

    wulf

    Apr 11, 2002
    Oxford, UK
    Nope - a e i o u definitely sounds like he's looking for more volume, not a subtle combination of tones from the two amps.

    My advice would still be to split the signal and run both in parallel. The only reason I could see for hooking the two up is if a e i o u prefers the sound of the Peavey preamp but wants the added power of the Ampeg power amp stage (so hooking Peavey pre-out to Ampeg power amp in).

    Of course, assuming the cabs are both 8 Ohms (so a 4 Ohm load if run together) it might be worth contrasting the two amps in parallel with just the Ampeg amp running into a 4 Ohm load.

    What you can't do is take two power amps that each make the signal (say) ten times louder and expect them to make the signal 100 (10 x 10) or even just 20 (10 + 10) times louder by chaining them together. You can chain amps together (that's what the preamp / power amp combo does) but you have to avoid giving any of the amp stages more input power than it is expecting.

    Wulf
     
  11. I was looking to just use my ampeg as the main thing, but have the peavey as a boost for the ampeg, to ultimatly give the ampeg more wattage derived from the peavey.

    the entire process seems way too dangerous and confusing that it is almost might not be worth it.Im sorry for bringing it up, I was just assuming you'd use a cable to have both amps togehter and be go to go.
     
  12. xyllion

    xyllion Commercial User

    Jan 14, 2003
    San Jose, CA, USA
    Owner, Looperlative Audio Products
    Nope, you can't do that. Power amps aren't building blocks that you can piece together for more power. If you hook their outputs together, you will most likely end up destroying one or both of them.
     
  13. wulf

    wulf

    Apr 11, 2002
    Oxford, UK
    It was worth asking the question - now you know without ending up with a smoking puddle of plastic and metal where your amps once were ;)

    If you can split the signal, then you can experiment with the two amps in parallel - that will give you a much bigger sound. This isn't a new idea - it's what bassists like Doug Pinnick of King's X and Amy Humphrey of Clatter have been doing for a while - do a search on TalkBass for Clatter or for posts under Amy's screen name of Tosya for more information about her set up:

    [​IMG]

    Wulf
     
  14. The thing that's unclear to me in all of these posts is: one cab or two?

    two power amps into one cab? nonononono!

    two amps each to it's own cab? Yes

    two amps into two 8 ohm cabs each? yowsa that would be fun!

    BT

    p.s. nice hair Amy!
     
  15. it would be 2 amps into 2, 8ohm cabs
     
  16. Try running the cabs in parallel first, that would be the simplest. Then you can sell the session bass and get more stuff!
     
  17. Johnny BoomBoom

    Johnny BoomBoom Supporting Member

    Jun 8, 2001
    Glasgow, Scotland
    Best bet is just run the Ampeg into the two cabs - you'llget the 350 w @4 ohms that way!
     
  18. wulf

    wulf

    Apr 11, 2002
    Oxford, UK
    That would give you most volume - although it would still be fun to experiment with the two rigs run side by side, which might give more 'depth' (and you could use one 'clean' and one for a more dirty, effected sound).

    Wulf
     
  19. Greg R

    Greg R

    Mar 11, 2003
    Avonmore, ON
    What kind of cabs are they? If they have more than one speaker each, maybe you can do a little wiring and bring them down to 4 ohms AND run a parallel rig. You would have more volume and get the most out of the amps as already mentioned.
     
  20. Michael Yetton

    Michael Yetton

    Dec 11, 2000
    Essex, UK
    incidently, how do you link two of the same amps? Not that im really after a 1.5k rig, I'm just curious!:rolleyes: