Hooking a cabinet/speaker up to a combo.

Discussion in 'Amps and Cabs [BG]' started by Basroil, Mar 2, 2006.

  1. Basroil


    May 25, 2005
    Lake Forest, CA
    Just out of curiousity, would it work to hook up a combo to a cabinet? I dont see any real problem with it, except the volume. Would it just be a lot louder at 3 with a cabinet hooked up then without? Also would it affect the sound in anyway?
  2. That depends alot on which combo and which cabinet.
    How many watts is the combo?
    Does it have an external speaker output jack?
    What's the impedance of the amp? (ohms)
    What's the impedance of the cabinet you wish to connect?
    Is the combo's speaker disconnectable or is it hard wired into the amp?

    If the amp's impedance is the same or lower than the cab, it's safe to try. If the amp is higher than the cab, you run the risk of seriously damaging the amp.
    If the amp is 4 ohms and the cab is 8 ohms, it would work, but you'd lose a big chunk of your amp's wattage. If they are both 4 (or even 8) ohms, you'll get max wattage from the amp.
    Please don't try to connect a cabinet to the combo's output with the combo/speaker still connected unless you understand impedance and ohms.

    Realistically.. if the amp is (let's say) 100 watts RMS, and you're wanting to try a single 15" cab, or maybe a 2x10 cab, it might work out as long as the impedance is correct.
    How will it sound? Will it be louder? That's going to depend alot on the cabinet's sensitivity..
    How about more info on the combo and the cab you want to try?

  3. spectorbass83


    Jun 6, 2005
    What he said ^

    What kind of combo is this?? Some are built for extension speakers - Yorkville, GK, Yamaha Etc....

    My old Yorkville 200W 2x10 combo was 8 ohms and had a minimum impendence of 4 ohms. This meant I could connect a 2nd cabinet (either a 2x10 or 1x15) to the speaker extension jack so long as it was 8 ohms. It worked well and gave me more bottom end.
  4. Basroil


    May 25, 2005
    Lake Forest, CA
    I know all the bass terms but, Im no expert on amps. :meh: Ill just get a louder combo.

    Its a 60W SWR btw
    * 60W power into 8 ohms (internal)
    * 12" custom-designed speaker and piezo tweeter
    * Extended-depth cab for enhanced bass response
    * Classic SWR preamp and Aural Enhancer circuitry
    * Post-EQ line out/tuner output
    * Stereo headphone outs with speaker defeat for silent practice
    * Mix input for practicing with CD or drum machine
    * Edgemount handles for easy portability
    * 16"W x 16"H x 16"D
    * 39 lbs.

    i dont know extactly which cab id connect, probaly an ampeg though, louder than the amp.

    Thanks for all the feedback! :)
  5. spectorbass83


    Jun 6, 2005
    Usually an extension cab would not be recommended for a 60W combo. The combo you have would ideally be used as a stand alone unit for personal practice/ low volume rehearsals. But to answer your original question - yes it would probably be louder, provided that there is a way to hook up an extension cab. Bottom line - if you are looking for more volume consider looking into a head/cab configuration. Best to ya man:bassist:
  6. 62bass


    Apr 3, 2005
    That SWR is not designed to run at at an impedance lower than 8 ohms from what I see in the advertised specs. Many low powered combos aren't. You're better of getting something with a bit of power and better quality speakers. Don't buy the GK Backline series or the other entry level stuff that other manufaturers sell. You'll be disappointed.
  7. BillyB_from_LZ

    BillyB_from_LZ Supporting Member

    Sep 7, 2000
    Since SWR doesn't include an extension speaker cabinet jack on the LA series amps (I presume that it's an LA12) you're not supposed to connect one.

    Bigger amp time I guess...
  8. LesS


    Mar 3, 2006
    no longer a member
    You might want to have a ¼” switching jack installed for your amp output. (It is a ¼ mono jack that has three terminals instead of two.)
    This way when you plugged in an external cabinet, it would disconnect your internal speaker.
    This way as long as your external speaker was 8 ohms it would not be running your amp below its minimum 8 ohm requirement.
    Your current internal speaker cabinet volume is probably about 1.3 cubic feet – if you were to get a cabinet of 3 to 5 cu ft you would be amazed at the difference in deep bass.
    Just be careful that the amp is turned off before unplugging or plugging in the external speaker cabinet, so that you don’t risk damaging the amplifier. (I’m not sure if combo amps that are hard wired to their internal speaker have good protection circuits.)
    -Les S
  9. BillyB_from_LZ

    BillyB_from_LZ Supporting Member

    Sep 7, 2000
    That would work, but you'd probably void your amp's warranty.

    For the cost of the modification, you could probably find a good used Peavey head (run a signal to it from the SWR's line output) and have two amps!

    I've seen plenty of older/yet solid Peavey bass heads for under $100!