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Ampeg B4-R and it's many power output options...

Discussion in 'Amps and Cabs [BG]' started by Phyrexian, Jan 8, 2003.

  1. Hi there,
    I've looking around for a new amp. I gave up on distortion in the amp and went for a decent overdrive pedal.
    That said, I just want a good sounding rock-amp.

    My eye felt on the Ampeg B4R.
    It's got many options and I know some of you guys up here own this amp and use it exstensively.

    This amp is a bi-amp model.
    The manual says the next thing:

    1350 Watts Mono-Bridged @ 4 Ohms (1000 Watts Continuous)
    840 Watts Mono-Bridged @ 8 Ohms (680 Watts Continuous)
    2 x 675 Watts @ 2 Ohms (500 Watts Continuous)
    2 x 420 Watts @ 4 Ohms (340 Watts Continuous)
    2 x 255 Watts @ 8 Ohms (205 Watts Continuous)

    There's 3 bi-amp options. I'm not yet interested in the mono-bridged options, but I might be in the future.
    In the beginning I'd like to use this amp with one Cabinet. Coudl I use only use ONE of the two 4 ohm channels? That way I could easily drive a 4x10 cab (somthing around 400watt power handling) with one of the two 340watts channels.
    My question is: is this good for this amp? I mean, can I use one of them two channels when in stereo mode without breaking the amp? Or does this amp always needs or two cabs connected, or one cab that can handle the huge power from the mono bridged mode?

    Could someone clear this issue out?
  2. After reading through the manual:
    It doesn't say you can't and it doesn't say you can. I've been playing a 400W cab with a 1000W amp for sometime now. If it were me, I'd just bridge it and run it into 1 cab. As long as you don't expect your cab to handle full power you should be fine. I use a Alesis nano compressor on the input side. I set the ration to 1:infinity and I set the sensitivity to kick in when I slap the strings with my hand. It doesn't come on unless I really bang the bass or :mad: accidentally drop it.
  3. alexclaber

    alexclaber Commercial User

    Jun 19, 2001
    Brighton, UK
    Director - Barefaced Ltd
    It should be fine, but if I were you I'd bridge the amp and just be sensible with the volume knob. (And if you're sharing your rig, switch it to just one channel for other bass players who may have less restraint).

  4. cb56


    Jul 2, 2000
    Central Illinois
    I have the B4r and have run only one channel several times with no problem. Since it is solid state and each power section is separate I don't think it will hurt anything. But then again, why not just bridge it into your 8 ohm cab at 680 watts and enjoy the extra head room? Either way you will enjoy the Br4. BTW if it's a small amout of distortion (overdrive) you want. Try pushing in the texture button and turning up your pre amp gain. See if you like the way that sounds.
  5. CB56,
    thanks, I was looking for an answer like yours.
    I would like to bridge such an amp, but I don't have the money to buy a bigger cab. If I'm careful a lower rated cab should handle the monobridged output but yeah... :)

    Yeah I like a small amount of distortion. That texture buttons seems nice for that purpose. Otherwise for a more grindy tone I'm using a distortion/overdrive pedal.
    I wanted a ProCo RAT; so I tried it out at a local shop. I found out it sucked out almost all of the low end out of my tone, so I'll wait until ProCo shows up with its RAT for Bass (I hope it'll come out eventually? Any news about it?)
    For now I'm using a DOD Bass Overdrive FX91. I noticed there's like no-one on this board that likes this pedal... :D BUT I DO! It gives me the mild overdrive I was looking for. I tried a Boss ODB-3 but that gave too much. I wasn't looking for guitarlike distortion or fuzz at all, but just a grittier tone.
  6. CraigV


    Jan 8, 2002
    I run an SVT-4PRO into a PR-410HLF , which is basicaly just a slightly bigger brother to the B-4R with a tube pre-. I run it bridged and use restraint on the master volume. However, Ampegs seem to have a nice feature....instead of giving you 90% of volume in the first three clicks of the dial (the old, "I'm blowing the doors off and it's only at 1 on the volume!!") the Ampeg rolls the volume in slowly, ramping it up more sharply after about 2 o'clock.

    Between a conservative setting and the use of the limiter, you should be able to enjoy plenty of volume and relative safety. Just be sure to get a good quality cabinet.
  7. Hi,
    thanks CraigV!

    What about a compressor. I know it cuts peaks and alters lows. But could it also be used for keeping the power output low? Like putting a break on the 1000 watt output at 500 so i can safely drive a 500 watt cabinet? Or is there another 19" tool for something like that?
  8. CraigV


    Jan 8, 2002
    Compression will help, but it's no firm solution, so don't go running out to buy one just for this (besides, good compressors cost more than good cabinets!). The limiter on the amp will stop clipping power from reaching the speakers. But, if you try to dissipate 1000 watts into a 500 watt cabinet, there will always be a chance of damage. The best solution is the free one...keep the volume down. There's not a lot of volume increase from "driven fully" to "blown", so be careful.
  9. cb56


    Jul 2, 2000
    Central Illinois
    I always wondered about that. I think that's why alot of people think (perceive) that Ampegs are underpowered when they are not. Gee my Hartke 7000 with the volume knob set at 3 is louder than my Ampeg B4r set at 6 .....

    Also thanks for mentioning the limiter on Ampegs. Always leave it on and let it do it's job especially if you are a heavy handed player like me.

    As far as 680 watts into your 400 watt cab, do a search on overpowering cabs and you will see that most folks here would rather overpower a cab than underpower one. Really do the search on tis and you'll get all the details. It's been explained alot better already on this board than I could explain it :confused: But it does make sense.....Hope I am :D
  10. CraigV


    Jan 8, 2002
    The under- vs over-power issue is a little misleading. While you can overdrive an amp and cause it to both produce much more power and cause that power to be of a 'dangerous' waveform (clipping, asymmetric, etc), the fact remains that overdriving a 200 watt amp to produce 400 clipped watts is only marginally more 'dangerous' than running a 400 watt amp at its rated maximum, in that if either amp is connected to a 200 watt speaker, its life expectancy is measured in minutes or at best hours.:D
  11. cb56


    Jul 2, 2000
    Central Illinois
    I guess the difference would be that you wouldn't be running your 400 watt amp at full volume into your 200 watt speaker.