Dismiss Notice

Psst... Ready to join TalkBass and start posting, make new friends, sell your gear, and more?  Register your free account in 30 seconds.

Bridging primer for idiots (like me)?

Discussion in 'Amps and Cabs [BG]' started by Planet Boulder, Dec 6, 2002.


  1. Planet Boulder

    Planet Boulder Hey, this is a private residence...man Supporting Member

    Nov 10, 2001
    6,482 feet above sea level
    I once had impure thoughts. Oh, and I pluck my ear hair.
    Okay, first of all the obligatory apology if a similar thread exists elsewhere. I hate duplicate threads as much as the next guy, but I searched for a thread which starts from square one for bridging, but only came up with threads which begin decidedly higher than square one.

    So here's the deal:

    I have never bridged an amp and I am utterly clueless as to how to go about doing so. I am looking to bridge a Carvin FET-1000 power amp into one 8ohm 4x10 Avatar using my Trace Elliot AH200 (with 12 band) as the preamp (while using one of the channels on the TE to run direct to an 8ohm 2x10 cab.

    The power amp itself features 2 1/4" outputs and two outputs to be used for bridging which resemble your standard stereo speaker hookups (yes, I am THAT friggin' clueless!!). My questions are as follows:

    - What the hell is a "speakon"?
    - How do I bridge this thing using those speaker outputs mentioned above?
    - What additional accessories do I need to be able to do this?
    - Who invented liquid soap and why?

    Apologies again, both for the possibility of duplicating and for my sheer, utter and embarrassing ignoarance on this subject. I've simply never done this before.

    Many thanks!
     
  2. FretNoMore

    FretNoMore * Cooking with GAS *

    Jan 25, 2002
    The frozen north
    OK, I'll take the easy one, please... :)

    Speakon is a connector for speaker cables, go to http://www.neutrik.com and look in their products section.
     
  3. FretNoMore

    FretNoMore * Cooking with GAS *

    Jan 25, 2002
    The frozen north
    ...and the last one too! :D

    William Shepphard first patented liquid soap on August 22, 1865

    All according to The History of Soap and Detergent

    Thank God for the Internet! :p
     
  4. And I'll try the other two:
    I don't see a manual for the old FET1000 on the Carvin site, but if it's like my Mackie, you need a speaker cable with a banana plug on one end (to plug into the amp) and a 1/4" phone plug on the other end (to go into the cabinet). Or, you could use a regular speaker cable and a banana-plug adapter that looks like this (part #AD42 in the Carvin catalog):

    [​IMG]

    For taking the output of one amp channel, you'd plug the banana plug into the black and red outputs (the ones that look like stereo speaker hookups) for that channel. There will be a ridge on one side of the jack that indicates which side should go into the black (ground) side. To bridge the output, though, you plug the banana connector into the red half of the output for both channels, to combine the output of both. The jacks
    are usually labelled which one one the "ground" in bridge mode. Also, there's usually a switch on the back of the power amp to change it from stereo, mono (both sides amplifying the same input), or bridge mode--be sure that's in the right position.

    Aside from the banana-1/4" speaker cable, you'll probably need a short XLR-XLR cable to take the DI output from your Trace and use it as an input to the power amp. You definately do NOT want to use a speaker output from the Trace to connect to the power amp!

    Mike
     
  5. Planet Boulder

    Planet Boulder Hey, this is a private residence...man Supporting Member

    Nov 10, 2001
    6,482 feet above sea level
    I once had impure thoughts. Oh, and I pluck my ear hair.
    Many thanks, Mike and Anders - you guys gave me exactly what I needed!

    Just ordered that converter from Carvin, so I should have what I need.

    Thanks again!
     
  6. Planet Boulder

    Planet Boulder Hey, this is a private residence...man Supporting Member

    Nov 10, 2001
    6,482 feet above sea level
    I once had impure thoughts. Oh, and I pluck my ear hair.
    So I've done everything outlined in mikezimmerman's post above with respect to properly bridging the amp and running my TE as the preamp.

    I'm getting sound, but not nearly enough. It's running mono (using the channel 1 selector as the volume) and there is virtually no sound at all until it hits about 3-4. It tops out at a very relatively quiet volume, almost as if it just was not getting enough juice. The amp itself possesses quality sound, just without the quantity, so to speak.

    The question is, could this be due to the outlet itself? We're talking 700w output when bridged. Has anyone else had this issue?

    Moronically yours,
    PB the Halfwit
     
  7. If your TE is like my SWR the balanced line out is line level (what ever the bass pickups put out is all that is getting to the power amp) if you have an effects send output on the back try that. That output is post pre-amp, the gain control and effects send knobs on your TE will now affect the volume.

    Good luck, John
     
  8. The only thing that comes to mind off the top of my head is that the output from the TE isn't hot enough to drive the Carvin power amp properly. What sort of output jacts does the TE have--does it have a DI XLR out jack? And does the Carvin have signal strength LEDs that might indicate how hard the amp's being driven?

    Mike
     
  9. Planet Boulder

    Planet Boulder Hey, this is a private residence...man Supporting Member

    Nov 10, 2001
    6,482 feet above sea level
    I once had impure thoughts. Oh, and I pluck my ear hair.
    mike - yep, I'm running a direct out with an XLR and it has the signal lights, which are being lit.