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Running at 2 Ohms...

Discussion in 'Amps and Cabs [BG]' started by Mike, Mar 20, 2003.


  1. Mike

    Mike

    Sep 7, 2000
    Cali
    I'm thinking of selling my Eden WT 300 with the recent acquisition of my Sans Amp RBI and picking up a Carvin 600 watt power amp. I will continue to use my EBS 2x12 (4 ohms) but may entertain adding another some day.

    The Carvin is designed to handle a 2 ohm load but that's a lot of juice for any amp. Anyone around here running a 2 ohm load? How is your power amp holding up? Any problems in warm, humid or other adverse weather?

    Thx.
     
  2. Turlu

    Turlu Supporting Member

    Sep 11, 2000
    Ottawa, Ontario CANADA
    I am running my Peavey T-Max head at 2 ohms no problem. I use 115 cabinet and a 212 cabinets, both 4 ohms and I never noticed any defects with my Peavey, which is a great amp by the way.
     
  3. BillyB_from_LZ

    BillyB_from_LZ Supporting Member

    Sep 7, 2000
    Chicago
    I'd compare the power ratings at 8, 4 and 2 ohms and see how close the power supply is to being out of juice.

    If the 2 ohm power rating is nearly twice as much as the 4 ohm rating (make sure the power ratings are determined at the same level of distortion, freq range etc.) then you'll know that the amp has plenty of reserves. If it's only a little more, then something is running out of steam...either the power supply or the output devices.
     
  4. Slater

    Slater Bye Millen! Hello?

    Apr 17, 2000
    The Great Lakes State
    Me too!

    My T-Max laughs at 2ohms :D !
     
  5. Mike

    Mike

    Sep 7, 2000
    Cali
    All righty... Tech guy I am not.

    If it simply splits the 600 watts at 300 per channel with a 2 ohm load, is it running out of power? I'm assuming no. There really isn't a boost in power with less resistance in this case it only divides it. Of course, it will do that if it is not bridged anyway.


    Is this what you were covering?

    Thx.
     
  6. Richard Lindsey

    Richard Lindsey

    Mar 25, 2000
    Metro NYC
    Forgive me if I'm belaboring the obvious but ... note that the Carvin, like most amps, will NOT handle a 2 ohm bridged load. That would be basically equivalent to a load of 1 ohm per side. The amp is rated down to 2 ohms *per side*. So if you got another cab like your first, you could not bridge the amp into both of them. You would have to either (1) run one off each side (4 ohms a side, for about 225/225 W, IIRC) or (2) run both off one side (2 ohms on on side, nothing on the other, for about 300/0 W).

    A suggestion too: if you buy a Carvin amp, why not spend a few extra bucks and get the 1000 W version? It's only $40 more, and more headroom is good to have.
     
  7. Hey paleale how are you liking your EBS now?I'm still liking my 12s.I'm using the RBI with a Carvin R 1000,bypassing the preamp so it's like having the 1000 watt power amp.My 210XLT and my SWR 212 are both 4 ohm and when I use them together the 350 watts to each works real well.And they both really like it when I bridge the amp at 1000 watts and just use one standalone.I don't think I'd want to try running each at 225 watts when running both,not enough head room.Nice choice for a preamp!:D
     
  8. Eric Moesle

    Eric Moesle Supporting Member

    Sep 21, 2001
    Columbus OH
    Be sure you're running two ohms UNBRIDGED. That amp won't bridge at 2 ohms.

    FWIW, just two weeks ago I drove my QSC PLX at 2 ohms for a long, loud gig, and it didn't barely get warm. I think you'll be alright.
     
  9. BillyB_from_LZ

    BillyB_from_LZ Supporting Member

    Sep 7, 2000
    Chicago
    I was looking at carvin.com...

    The ratings are:

    125 watts per channel into 8 ohms
    225 watts per channel into 4 ohms (almost double...so far so good)
    300 watts per channel into 2 ohms (not much more than at 4 ohms...something is reaching capacity...probably the power supply)

    Bridged, it's rated 450 into 8 ohms, 600 into 4 ohms.

    Personally, I wouldn't run it at 2 ohms in the stereo mode or at 4 ohms bridged.

    I've bridged my PLX2402 and run it at 4 ohms. I felt its hot breath on the back of my neck (we played way too loud in a tiny bar with a small stage and since I'm "only" the bass player, I had to stand in back). I never ran it bridged again.
     
  10. bentem

    bentem

    Oct 18, 2002
    Rockville, MD
    is there a difference between bi-amping and sterio( or full range?)
     
  11. BillyB_from_LZ

    BillyB_from_LZ Supporting Member

    Sep 7, 2000
    Chicago
    Difference from what perspective?
     
  12. bentem

    bentem

    Oct 18, 2002
    Rockville, MD
    well, i thought i understood one concept, which was that a sterio poweramp has two poweramps, and each can be sent to a sifferent speaker cabinet, and there is a control knob that controls at what frequency the signal is split.

    but people keep using all theese different terms
     
  13. BillyB_from_LZ

    BillyB_from_LZ Supporting Member

    Sep 7, 2000
    Chicago
    A stereo power amp does have two separate power amplifiers in one box. You can run them "dual mono" where you have one input (like from a bass preamp) and send each output to full range cabinets. This works well for cabs on either side of the stage as you can control their levels independently.

    Biamping refers to splitting the output of the preamp into two frequency bands with an electronic crossover then sending the highs to one channel of the power amp (which powers the high frequency cabinet) and the lows to the other channel (which powers the low frequency cabinet).

    Most stereo amps can be "bridged" where they are converted into a single channel power amp which can produce a lot more power.

    Hope this helps:)
     
  14. bizzaro

    bizzaro

    Aug 21, 2000
    Vermont

    A suggestion too: if you buy a Carvin amp, why not spend a few extra bucks and get the 1000 W version? It's only $40 more, and more headroom is good to have.



    Yea, What Richard said:bassist:
     
  15. Here is what you can do with that amp. (I've got the 1000 model)
    1. Run 1 or 2 (8) ohm cabs bridged mono
    2. Run 1 (4) ohm cab bridged mono
    3. Run 2 (4) ohm cabs parallel mono or bi- amped but not bridged.

    Good luck
     
  16. Mike

    Mike

    Sep 7, 2000
    Cali
  17. DRN

    DRN

    Mar 17, 2002
    Las Vegas
    I have a crown K2 (heat sink no fans) I was running a sound gig for an all day outdoor gospel show. The temperature got up to 99*F and they had no tents for the gear and no tents for the stage. The K2 (running at 2 ohms stereo) was at the bottom of a 18 space shock mount flight case that was filled.
    I ran that thing all day, all out and it did not even flinch. I did have a small house fan on the back of the rack but that was it.
    The bands were not so lucky. Keyboard displays etc started to fail. They were putting damp towels over the equipment trying to stop the sun from killing everything.

    Go ahead run it at 2 ohms it just has to be stereo.

    Drn
     
  18. jcadmus

    jcadmus

    Apr 2, 2000
    Me too, also, too.

    T-Max, two cabs, 2 ohms.

    No problem.

    I love this rig.