Ohms, wattage, volume question

Discussion in 'Amps and Cabs [BG]' started by vegaas, Jun 13, 2005.

  1. vegaas


    Nov 6, 2001
    Hey Guys,

    I just bought a Mesa/Boogie M-Pulse 360. Here is the problem, I play in two bands, so I have been using my Eden RR 600 for both. I use the bridged feature to get the full 600 watts going to my 8 ohm cab.
    When I ordered the M-Pulse I knew it was lower wattage but I wasnt too concerned because the band I want to use it for is nowhere near as loud as my metal band.
    Just got the M-Pulse and noticed on the back that it is a recommended 4ohm with minimum of 2ohm. No bridged mode like my Eden has.

    So here is the question, if I get all 600 watts from my Eden into my 8 ohm cab by using bridged mode, how much wattage am I going to lose with this M-pulse? The M-Pulse is already only 360 watts, now without a bridged mode I know it wont be sending all 360 to my 8 ohm cab. Was it a mistake to get the 360? I am slightly concerned here. I love the power of full 600 watts of the Eden, with it I know I never get burried in the mix at shows. Did I make a big mistake by trying to save some money and getting the 360 instead of the M-Pulse 600? Is the 4ohm output into an 8ohm cab going to make a decernable difference?

    Ok, sorry for rambling, any info would be greatly appreciated.
  2. IvanMike

    IvanMike Player Characters fear me... Staff Member Supporting Member

    Nov 10, 2002
    Middletown CT, USA
    well for fun you can check out the FAQ sticky at the top of the forum and click on the link to the ohms FAQ.

    anyhow, you'll have to check with mesa to find out how many watts the amp will put into an 8 ohm load. It will probably be no more than 250. At that point, if mesa and eden rate their wattage the same way, you'll be losing about 3-4 dB.

    Of course, the 1st thing to do is test both amps together into the cab (one at a time) and see what the max volume of each is. You may find that the mesa just doesn't cut it, or you may find that the volume difference is acceptable.

    A solid state amp will be able to power any load at or above it's minimum impedance rating, so there's no problem with using an 8 ohm cab with the mesa
  3. The mpulse is a mono amp, so there is no bridging. So, into 8ohms, that amp puts out a very small amount of wattage.

    I hate to say it, but I think you might have made a mistake in not going for the additional wattage of the 600. The good news is, the Mesa line is very loud. If you can get that thing into a 4ohm load, you will probably be OK for all but the loudest situations.
  4. The good thing though is that if you get another 8 ohm cab, it will run at 4.

    *correct me if I'm wrong* Though I'm sure you don't plan on getting another cab anytime soon.
  5. If its rated at 360W into 4 ohms, its probably only putting out 225-250W into the 8 ohm speaker, like someone else said.

    But if will drive a 2 ohm load, make sure it isn't rated at 360w @2 ohms. Then it would be about 225-250w at 4 ohms, and no more than 150 or so at 8 ohms. That would be a pretty drastic cut in wattage from what you're used to.

  6. vegaas


    Nov 6, 2001
    Well, I just bought another 8ohm cab. Found a deal on an Eden 1X10 XLT to go on top. Its used, and looks a bit old, but sounds great. So that should take care of the ohm problem.

    Also, throughly scoured the owners manual for the M-Pulse, 4 ohms gives the optimal output, so the 360 is rated to 4ohms. In addition, they say the 360 is where it may start to clip, but it can go much much louder. For the 600 they it can peak at 1000, so I guess the 360 would probably peak at 500 or 600? Let me know if you have any insight to this.