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Speakon questions

Discussion in 'Amps and Cabs [BG]' started by Dan Molina, Jul 23, 2005.


  1. Dan Molina

    Dan Molina TalkBass Secular Progressive

    Jul 17, 2002
    Murr Town, California
    I just got my new QSC poweramp and I have a few questions about the speakons.

    1. When running bridge mono do I need 2 speakon cables wired for bridge mono for connecting to 2 8ohm cabs?

    2. Do I need another two cables for running my cabs in parallel (I think I worded that correctly)

    3. Will my 1/4 jack pop out of my cab if running in bridge mono?

    Thanks guys I'm new to this power/pre setup.
     
  2. To fully answer your question, I need to know what inputs are on your cabs.

    As far as running the amp in bridge mono - check your dip switch settings on the back of the amp....I believe 4-9 need to be to the right. The clip limiting and filter switches for channel two need to be to the "off" position (left). Then, all you need is a speakon (or banana) to ? cable to go to the first cab, then a ? to ? cable from the first cab to the second cab. You would then be running both cabs (in parallel) for a 4-ohm load (read, LOTS of watts from a 2450). You do not need special "dual" cables for this setup.

    - If, however, you'd like to run the amp in parallel (actually a nice solution here as you'll still get something like 450 watts a channel (per cab), you need to set up your dip switches for parallel (look at the legend on the back right side of your amp - or look in the manual). Once set up, all you need is to patch your preamp to channel one. You then need two cables from your amp - one to each cab from respective channels. The way I do this is have channel 1 run my 2x10 (with the 50 hz filter on) and channel 2 runs my 2x12 (with the 30 hz filter on). This gives me 700 watts for each cab (my cabs are 4-ohms) as well as some nice filtering to allow the cabs to work best with their driver's basic frequencies.

    Hope this helps.

    Jay
     
  3. Dan Molina

    Dan Molina TalkBass Secular Progressive

    Jul 17, 2002
    Murr Town, California
    I have two 1/4 jack imputs on both of my cabs.

    so I do need 4 cables? 2 regular and 2 wired for bridge mono?
     
  4. pbd

    pbd Commercial User

    Jul 17, 2003
    Metro Detroit
    owner Procables N Sound
    You could buy two cables, banana to 1/4". These would be able to bridge mono or stereo for you. Using the banana's across the two red posts will bridge it (plus the dip switches set properly). Using the banana's each side would, of course, give you a stereo setup. The speakon needs to be wired 1+/2+ for bridged mode so this type cable would only work for one situation...bridged.

    ...Will my 1/4 jack pop out of my cab if running in bridge... mono?
    Anything is possible!
     
  5. Dan Molina

    Dan Molina TalkBass Secular Progressive

    Jul 17, 2002
    Murr Town, California
    That's a scary though.

    Thanks Jay and pbd. You guys were very helpful.
     
  6. Munjibunga

    Munjibunga Total Hyper-Elite Member Gold Supporting Member

    May 6, 2000
    San Diego (when not at Groom Lake)
    Independent Contractor to Bass San Diego
    Using Speakons for bridged mono means wiring them specially for that. As pbd said, the Speakons need to be wired 1+/2+, but that's just at the amp end. The speaker end should be wired 1+/1-. You must always use it connected in that way, if you connect it the other way, it won't work. You can make your own cables with the appropriate connectors, with a Speakon on one end, and a 1/4-inch plug on the other. These would be wired 1+/2+ on the Speakon, and tip-sleeve (either way) on the plug end. Call Sweetwater customer service, and they can have ProCo make this for you. They made some Fat Max cables to my specs for me.

    In bridged mode, you can use one Speakon cable from the amp to a speaker, and then just daisy chain to the next speaker. In stereo mode, you cannot use the cable you use for bridged mono. You need two other cables wired 1+/1- at both ends.

    If you're using banana plugs on the amp end, then you can use that cable and one other, since you'd just plug an ordinary banana plug into the two red posts for bridged.

    Oh, and I don't see any reason why a 1/4-inch plug would up and pop out of your speaker. That's weird.
     
  7. Time Divider

    Time Divider Guest

    Apr 7, 2005
    I don't mean to hijack the thread, but I have a speakon question of my own. The other day I was at GC (gasp) and asked if they had a 3-foot speakon for running from my amp to my speaker cab. They didn't have one.

    Does anyone know if they exist, and if so, where I can get one?
     
  8. Dan Molina

    Dan Molina TalkBass Secular Progressive

    Jul 17, 2002
    Murr Town, California
    Thanks Munji.

    I read about the 1/4 popping out in an older thread on this forum. I read the preasure builds up inside the cab and pushes the 1/4 out.
     
  9. Dan Molina

    Dan Molina TalkBass Secular Progressive

    Jul 17, 2002
    Murr Town, California
  10. Monomer

    Monomer

    Jul 22, 2005
    I would out speakon connecters at the cab end.

    1/4 plugs arnt all to good with current, and they don't lock into place like Speakon does.

    (Taken straight from the manual) Use ch1's front panel controls, and output. Wire the speakon 1+ as positive on the speaker, 2+ as negitive on the speaker's end.



    be sure NOT to drive anything lower than a four ohm load. (no 2 ohms)
     
  11. I'm extremely skeptical of the "1/4 inch poppong out of the connection because of the pressure" concept.

    If I do my math right...a 1/4 inch connector has an area of .05 square inches. If it takes 5 punds of force to pull the connector out, that means...5 divided by .05...equals 100 psi of pressure in your cabinet.

    A wooden speaker cabinet would explode instantly with 100 psi of air pressure in there.

    Suppose it only takes 1 pound of force to pull the connector out. That's still 10 psi of pressure in there, which is far more than the paper speaker cones could withstand.

    So the mathc says there ain't gonna be enoguh pressure in there for this to happen. Now, maybe if the plug wasn't pushed in all the way, or the jack was really messed up, there wouldn't be anything securing the plug, and the cord's own weight might pull it out of the jack.
     
  12. Lots of great information here, but as the original poster asked a fairly simple question, and he's let us know that he has two 1/4" jacks on the back of his cabs, let's get back to basics on how he can run his cabs in bridged mode or in parallel:

    - Bridge mode - As Munji said, your simplest solution would be to set up your dip switches for bridged mono, use a banana to 1/4 cable (put the banana across the red terminals of the power amp; positive usually on channel 1, negative on channel 2). Then simply run a 1/4 to 1/4 inch speaker cable from the first cab to the second cab. That will allow the amp to see a 4-ohm load and produce all 2400 watts. Probably a good idea to set the 30 hz filter dip switch on as well.

    - Parallel mode - this mode allows a single input to drive both channels, however, each channel retains it's own filter, gain, and clip limiting settings. This way you can tailor the amp for your cabs on each channel while at the same time driving BOTH channels from a single input to channel one.

    How to do it: As PBD said, set up your dip switches for parallel operations (recommend 50 hz filter for your 2x10, 30 hz filter for your 2x12). Patch your preamp to your channel one input. Use one banana to 1/4 inch cable from channel one to one cab; use another banana to 1/4 inch cable from channel two to the other cab....voila' - you're in business.

    These would be the simplest ways to do this...obviously the advice above is great for working with speakon cables in bridge mode, but if you want a "right now" plug and play solution, just get a couple of banana to 1/4 inchers (and a 1/4 inch to 1/4 inch for the bridged mode setup) and be done with it.

    Take care,
    Jay

    always IME and IMHO
     
  13. Thunderfunk

    Thunderfunk

    Mar 27, 2004
    McHenry, IL
    I haven't seen them in a long time, but Switchcraft use to make a 1/4" phone plug with a knurled ring on the end that would screw onto the threads of the jacks to keep them from pulling out.
     
  14. Munjibunga

    Munjibunga Total Hyper-Elite Member Gold Supporting Member

    May 6, 2000
    San Diego (when not at Groom Lake)
    Independent Contractor to Bass San Diego
    Sure. Sweetwater has them. I've got several with different ends on them. They're also very easy to make, since there's no soldering involved. Just get a couple Speakon connectors and some 12-gauge, two-strand speaker wire. Strip the ends of the wire about 3/8 of an inch, stick the ends into 1+/1-, and tighten the screws. Done.
     
  15. Dan Molina

    Dan Molina TalkBass Secular Progressive

    Jul 17, 2002
    Murr Town, California
    the 1/4 to 1/4 is just a regular speaker cable right? or does it need to be midified?
     
  16. pbd

    pbd Commercial User

    Jul 17, 2003
    Metro Detroit
    owner Procables N Sound
    1/4's can only be wired one way.
    Though they tend to get weighty, the banana's can stack into each other. You could only have the two cables and be able to use them for both setups.
    A solderless setup would be you buying a 1/4 to 1/4 then cutting it in half and adding your own speakon's (which don't require solder). Then purchase another 1/4 to 1/4 and you'll be set.
     
  17. Dannyboy15,

    Yes, just get a normal (recommend 12 or 14 gauge) 1/4 to 1/4 inch speaker cable for patching the cabs together and you'll be set.

    Jay
     
  18. Monomer

    Monomer

    Jul 22, 2005

    you can wire a 1/4 two diffrent ways, one being 180degrees out-of-phase.

    tip is usually positive, sleeve is usually negitive.
     
  19. Monomer

    Monomer

    Jul 22, 2005
    And speakons can be soldered. soldering is better over the standered screw method, as the screw method isnt all to secure.
     
  20. catdriver

    catdriver

    Apr 19, 2005
    Park City UT
    I've not heard this specificaly, but I have heard that a large amount of current run across the very small contact between a 1/4 and it's socket can spot weld the connector in place...