Behringer EP1500 problems

Discussion in 'Amps and Cabs [BG]' started by seanm, Nov 10, 2005.

  1. seanm

    seanm I'd kill for a Nobel Peace Prize! Supporting Member

    Feb 19, 2004
    Ottawa, Canada
    I know, I know, but I need a cheap power amp for using once a week... But my Behringer mixer has been reliable...

    Short version: Bridged I could not get near enough volume before clipping the amp. So I ended up one side maxed out into a CXL-112. This was adequate. What did I do wrong? (Except buying a Behringer).

    Long version:So I bought an EP1500 and brought it home. It is huge, but not real heavy. I setup the amp to run bridged and plugged a passive P bass straight in. Both channels show signal so I think I have it bridged correctly. FYI: I could practice in the bassment(sic) at this level.

    So I plug in my ARTs Mic Pre. Volume seems ok. But then I run my iAMP at less than 1 in the bassment. Found out the cab I wanted to use has a bad speaker :( Switch to CXL-112, a very efficient cab.

    So I go to practice. This is a fairly loud rock trio. I set the mic pre to just before clipping and start up the amp. And I carefully turn up the volume, and up, and up, until the amp starts clipping :scowl:

    So I turn down the pre and crank it higher. I could not get enough volume :bawl: So I turned off bridged mode and ran one side (260W). I was now able to run the pre much hotter. This was just *adequate* with the amp cranked and the pre set as high as I can before the amp starts clipping.

    After practice I turned bridging back on and tried using the XLR out from the pre to the XLR in on the EP1500 and it worked better, but I still did not get much volume compared to my iAMP.

    Bridged:
    DIP: ON OFF OFF OFF OFF ON ON OFF OFF ON
    or
    DIP: ON OFF OFF ON ON ON ON OFF OFF ON

    Unbridged:
    DIP: ON OFF OFF OFF OFF OFF OFF OFF OFF ON

    Am I doing something wrong, or is the amp fragged?
     
  2. Justice

    Justice

    May 24, 2002
    Houston TX.
    Check the settings or your preamp, does it have a -10 +4 switch? How is it set? It sounds to me like your pre is not putting out enough signal to drive the amp.

    If you think the amp may be bad, take it back and test it at the store and get an exchange if it is bad. My band has 3 of the EP series amps (the EP1500 in my rig, which I have had for over 2 years since they were first introduced) and 2 EP2500s in our pa, they have all been nothing short of solid, reliable amps.
     
  3. seanm

    seanm I'd kill for a Nobel Peace Prize! Supporting Member

    Feb 19, 2004
    Ottawa, Canada
    Actually, the pre seems to have *too* much output. My problem was clipping the amp, not the preamp. This is a mic pre that also works as an instrument pre. It can provide 70dB+ of gain!

    Yeah, I am starting to think I just got a lemon. Sh*t happens.
     
  4. andruca

    andruca

    Mar 31, 2004
    Madrid (Spain)
    I also use the EP1500 on my bass rig (not bridged, one cab per channel, inputs in parallel on the switches). I didn't have a single problem with it (almost a year now). It's reasonably loud. But I discovered that maxing the volume on the power amp and controlling it at the preamp (I use an RBI) often made me run out of headroom. What I do now is set the preamp almost maxed (3-4 o'clock) and then control the level with the power amp's knobs. I put them at 9 o'clock when rehearsing and it's huge (I ran 2 Hartke cabs -4.5XL + 215XL-). I never had to go further than 11 o'clock live. I also read that this also helps reduce the noise floor. One more thing. The fact that the red "peak" leds light from time to time doesn't mean that audible clipping is taking place. I found this in live situations where the led went on all the time without any effect on sound. Good luck!

    ANDRUCA

    EDIT: Although I also have a good experience with this power amp, I'm not that confident. I'll save for a Peavey or Yamaha power amp and leave this as a pretty decent backup. I mean, a power amp is a critical enough piece of gear not to mess with inconsistent QC issues. I have other Behringer gear and has proven reliable too, but I cannot shut my ears to other people's experiences.
     
  5. seanm

    seanm I'd kill for a Nobel Peace Prize! Supporting Member

    Feb 19, 2004
    Ottawa, Canada
    Interesting. In this case the clipping was *very* noticable. Sort of a staccato "da da da da da".
     
  6. Justice

    Justice

    May 24, 2002
    Houston TX.
    I run mine bridged mono to 2 8ohm cabs....never clips

    one of our 2500s clip lights come on on one side (durmmers monitor) I think it is due to the fact that he is using a single 8ohm cab where as the the other side of the amp is running 2 8ohm monitors for my guitar player and myself.


    Take the amp back and get another, they really are good amps.
     
  7. seanm

    seanm I'd kill for a Nobel Peace Prize! Supporting Member

    Feb 19, 2004
    Ottawa, Canada
    So I took the amp back to the store. The sales guy asked me how I setup the amp. When I said I used the speakon to connect the speaker he said "And did you rewire the connector?" :eek:

    So I have not tried it yet, but it looks like user error. I would use the emabarassed smilie here except:

    1. It looks obscene, not embarassed.
    2. I am so used to making mistakes I don't get embarassed that easy :D
     
  8. seanm

    seanm I'd kill for a Nobel Peace Prize! Supporting Member

    Feb 19, 2004
    Ottawa, Canada
  9. Justice

    Justice

    May 24, 2002
    Houston TX.
    Doh, that would definitly make a difference! I didn't think about the speakon being wired wrong since the last time i hooked up mine with the wrong cable end, i got NO sound, and you were getting sound, and I wasn't thinking...blah blah..

    Let us know the results of your next test ^^
     
  10. Passinwind

    Passinwind I know nothing. Commercial User

    Dec 3, 2003
    Columbia River Gorge, WA.
    Owner/Designer &Toaster Tech Passinwind Electronics
    I was just reading though this thread, waiting for that shoe to drop. It seems to happen couple of times a week on Talkbass. :cool:
     
  11. seanm

    seanm I'd kill for a Nobel Peace Prize! Supporting Member

    Feb 19, 2004
    Ottawa, Canada
    Moi aussi! Since I was getting output, I assumed the cable was right.

    I hooked it up with the right connections in the bassment. I can now put tons of gain on the preamp without a flicker of clipping. The volume also seems way higher. I think it is working :D

    Now if I can get the speaker fixed, I am good to go!
     
  12. gilbert46

    gilbert46

    Sep 21, 2004
    Sacramento, CA
    I did this same thing with my crown amp. The wires inside the speakon need to be switched around. be prepared for loudness.....
     
  13. bazzanderson

    bazzanderson

    Oct 7, 2002
    Austin, TX
    I got a custom +1/+1 speakon to 1/4" cable from Procables-N-More. (might have been +2/+2...I don't know the jargon)...I do know that if you're bridging and mono a typical speakon cable (most are wired +1/+2...something like that) won't work. Some of amp savvy guys can correct the above attempts at the technical side. I do know that once you get this sorted out you are going to be surprised. I run mine bridged mono into a Peavey 2X15 (soon to be replaced with a Peavey Pro 410). It's loud as hell. I drive it with an RBI. I've used the RBI's level as master and the channel 2 level on the 1500 as master. I get much louder results when setting the RBI level at max and using the power amp's channel 2 volume as master. Play around with it...with a pre/power there are endless possibilities.
    -Bazz-
     
  14. seanm

    seanm I'd kill for a Nobel Peace Prize! Supporting Member

    Feb 19, 2004
    Ottawa, Canada
    I decided to go with banana plugs. I use speakons for all my speaker cables and was worried that in a hurry I would use the "bridged" cable with a non-bridged setup.

    For a preamp I am using an AMZ mini-boost (Fulltone Fatboost is a copy of this). No gain, no volume, no tone controls, just plug and play.
     
  15. seanm

    seanm I'd kill for a Nobel Peace Prize! Supporting Member

    Feb 19, 2004
    Ottawa, Canada
    Ok, a followup. Took the amp/cab and two preamps to practice two weeks ago. The first preamp is one I made myself, the second was an ARTS MP as a backup.

    Well the cab had a bad speaker so I plugged into an old 2x12. Not enough volume with my preamp. With the ARTS I had the gain dimed, the +20dB switch engaged and the volume at full and it was adequate, but just!

    70dB of gain seems a bit much. Many "real" preamps such as the Tech21 RBI have less than 20dB of gain. So I make some mods to my preamp. Try it again last week, still not enough, but if I max out the amp I can use it :scowl:

    Well, to make a long story short, it turns out to be an impedance mismatch! My preamp needs at least a 100k input impedance and prefers much higher. The ARTS also wanted a high input impedance (I should have used the balance out). The EP1500 has a 10k input impedence. So I added an output buffer to my preamp and now I have too much gain :D

    At tonights practice I had the power amp at 9:00 and was loud enough :bassist: Plus, I fixed the cab. So I am now one happy camper.