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

crossover = power amp ???

Discussion in 'Amps and Cabs [BG]' started by spidersbass, Dec 3, 2004.


  1. spidersbass

    spidersbass

    Nov 29, 2004
    Downtown L.A.
    when using a crossover to connect 410's speakers and 2 10" subwoofers, do you need a seperate power amp just for the subwoofers?
     
  2. NJL

    NJL

    Apr 12, 2002
    San Antonio
    not unless you have a 2 channel power amp

    :)
     
  3. spidersbass

    spidersbass

    Nov 29, 2004
    Downtown L.A.
    2 channel? whaddaya mean by that? my head can connect two cabinets if thats what you mean
     
  4. NJL

    NJL

    Apr 12, 2002
    San Antonio
    ah, i see

    i thought, for some reason, that you had a power amp/pre type set up like me. i have a qsc power amp coming from a ampeg preamp.....my power amp has two channels

    in re your questions on Bi-Amping, you may want to use the term "bi-amp" in the search area, i know there should be some info.

    good luck!
    :)
     
  5. nonsqtr

    nonsqtr The emperor has no clothes!

    Aug 29, 2003
    Burbank CA USA
    active crossover = goes "before" the power amp, and needs one power amp for each output (ie for each speaker)

    passive crossover = goes "after" the power amp, needs only one power amp, but it better be a big shoebox if it's going to handle live gigging power
     
  6. Eric Moesle

    Eric Moesle Supporting Member

    Sep 21, 2001
    Columbus OH
    I don't understand what you mean when you attempt to make a distinction between the 10's in a 4x10 and "subwoofer" 10's. There's really no difference. The only difference in a "sub" is the enclosure.
     
  7. Sundogue

    Sundogue

    Apr 26, 2001
    Wausau, WI
    A crossover does nothing more than seperate the frequencies. It allows you to send one group (say 100Hz on up), and another group (say, everything below 100Hz), to two different power output sources (power amps), that will then drive the cabs they are attached to.

    You have the HA4000, right? It is not a 2 channel power amp.

    It does have a built in crossover. Use the sub out and it will send everything below 100Hz to a seperate power amp that drives your seperate 210 "sub" cab.

    Note that just because you have a seperate cab and you might send everything below 100Hz to that cab, that does not automatically make it a good sub cab. As Eric mentioned, while some 10" speakers are more suited for use as a sub (such as Eminence HL10's), it's the cab design that makes the cab a true "sub" cab.
     
  8. spidersbass

    spidersbass

    Nov 29, 2004
    Downtown L.A.
    does that seperate power amp need a volume control??? cuz a buddy of mine has one, but it doesn't have a volume control. and how many watts should that seperate power amp be? my 2 10" subs are 600 watts each, and i connected them in series to higher the impedence to 8 ohms.

    any suggestions on a good power amp???
     
  9. Sundogue

    Sundogue

    Apr 26, 2001
    Wausau, WI
    Look for a power amp that is rated for about 1200 - 1800 watts at 8 ohms then.

    The sub cab would be rated at 1200 watts at 8 ohms (two 600 watt speakers). Your HA4000's ohm rating will not be affected by the sub cab then, because a different power amp will be driving the sub cab. So you should be running a 4 ohm cab out of your HA4000, or it will only put out 200 watts into an 8 ohm cab. It will only put out 400 watts into a 4 ohm load (a single 4 ohm cab, or two 8 ohm cabs).

    If your sub cab is 8 ohm, and your 410 cab is 8 ohm and you run both out of your HA4000, then the HA4000 will put out 400 watts. Once you get a new power amp for your subs and run it with the HA4000's "sub out", then the other amp will drive the 8 ohm sub cab, and the HA4000 will drive the 8 ohm 410 cab at only 200 watts.

    And, no...a power amp does not need a volume control. In fact, on power amps, it's not really a volume control, it's just an output gain (yeah, a volume control, but it really just allows you to cut back on the power).
     
  10. billfitzmaurice

    billfitzmaurice Commercial User

    Sep 15, 2004
    New Hampshire
    Owner, Bill Fitzmaurice Loudspeaker Design
    Judging by the 600 watt rating (probably not accurate) and 4 ohm impedance of your subs I'll go out on a very short limb and guess your subs are autosound. If that's the case you'll likely be very disappointed in their performance, as they are not designed to operate to low frequencies outside of the confines of a car and lack adequate sensitivity for live pro-sound applications.
     
  11. spidersbass

    spidersbass

    Nov 29, 2004
    Downtown L.A.
    the 2 subs are in a closed box with 2 holes on the bottom (called "downfiring"). my bro tried it on his stereo system, sounded (i mean "felt") pretty cool. so it should work for my bass

    thanks sundouge for the advice