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Power Amp

Discussion in 'Amps and Cabs [BG]' started by spalka621, Oct 8, 2005.


  1. spalka621

    spalka621

    Jul 26, 2005
    Sioux Falls, SD
    This might be a stuid question but is there any way i can make a power amp with two channels feed into one cab.
     
  2. That is called bridging the amp. Many power amps are configured to allow this kind of operation. If you tell us what amp you are talking about we can give you specific advise.
     
  3. spalka621

    spalka621

    Jul 26, 2005
    Sioux Falls, SD
    o is that bridging, well the manual says its not a good idea but anyway its a samson servo 260
     
  4. Looks like the 260 doesn't support bridging, only the servo 550. Which means no, there is no way to combine the outputs of both your power amp channels into one speaker.

    Randy
     
  5. If the amp doesn't support bridging, which is what steve is saying, this moves things beyond the "not a good idea" realm, into the "definately don't do it!!" category.... :D

    Sorry about that, my old Hartke is in the same category. Two channels, can't be bridged.
     
  6. tadawson

    tadawson

    Aug 24, 2005
    Lewisville, TX
    You used to be able to get external phase inverters to run amps which don't have onboard bridge mode to run bridged. I haven't seen one in a while, but bridging is nothing more than inverting one channel, and then the load sees the voltage difference. Unless there is an unusual power supply or amp config (I have seen a few amps that were true differential, and those will NOT bridge - each channel effectively already is . . . ) you could probably do it this way, but be careful if you try until you are sure that it will work. Also, be aware that a bridged load is seen by each channel as half the total connected load, IE if you power a 4 ohm cab bridged, each channel MUST be able to drive a 2 ohm load or the amp will get hurt . . . . .

    - Tim
     
  7. There are several schemes available to make an amp bridgeable, such as the external inverter. The Elliott Sound web site shows how to use the long-tailed pair to invert one amp's signal. http://sound.westhost.com/project20.htm Not as simple as it sounds, though. And as you mention, if the amp can't run a 2 ohm load on each channel, it can't run a 4 ohm load bridged (my dilemma, so I gave up on converting my hartke to be bridgeable)
     
  8. Even if you could bridge it on your own with the inverter, you'd only get 260W at 8 ohms. Just not worth it.

    If you need more power, get a more powerful amp or one that supports bridging. You can easily find amps more powerful than that even when they're not bridged. That's a pretty small amp, all things considered.

    Randy
     
  9. +299

    That's how much American Musical wants for a QSC RMX850.

    830 watts bridged into 4 ohms. For $299 including shipping.... :cool:
     
  10. fdeck

    fdeck Supporting Member Commercial User

    Mar 20, 2004
    Madison WI
    HPF Technology LLC
    There can be many reasons why a stereo amp is not bridgeable, most notably if each channel is already configured as a bridge amp in its own right. Even if you could bridge this amp, you would be running it under conditions where it will generate absolutely the most heat. This is how you will find out if Samson makes a credible bass amp. There is a reason why most 300-Watt class-AB bass amps have cooling fans.