Denon 3801 to drive SVS subwoofer?

Discussion in 'Archived Threads 2001-2004' started by Purnam, Aug 5, 2001.

  1. Purnam

    Purnam Auditioning

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    I am planning to purchase a Acuras 200x3 to power my front and center channels. I also have a 3801 (105 watts per channel x 5), and will use 2 channels on the 3801 to power my 2 rear speakers.
    Can I use one of the 3 remaining front channels on the 3801 to power an SVS cs-20-39 subwoofer? i.e. Take the subwoofer out and feed it into, say, the Center channel on the 3801. The 3801 product literature has each channel rated at 105w/channel 8ohms, 150w/channel 6 ohms, and 220w/channel "dynamic".
    Any issues? Will this work?
     
  2. John Kotches

    John Kotches Cinematographer

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    It depends.
    The SV Subwoofer is a 4 ohm load, and I doubt seriously the Denon 3801 is designed to drive a ohm load for any length of time.
    Regards,
    ------------------
    John Kotches
    Contributing Writer
    Secrets of Home Theater and High Fidelity
     
  3. John_RK

    John_RK Extra

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    OK, I'll confess to thinking that a receiver rated at 100 watts per channel into 8 ohms would deliver considerably more than that into 4 ohms without any problem. Apparently, there are other issues to consider.
    My plan was very much like Purnam's except that I was planning to use an Onkyo TX-SV 828 to drive one or possibly two SVS subs. In an e-mail, Tom from SVS said the Onkyo would work fine "if it can handle a 4 ohm load". That caveat, along with John's comment, have me concerned.
    This may be a dumb question (never stopped me before) but how do I know if the receiver can handle a 4 ohm load? I've taken a look through the owner's manual without any revelations. Can anyone provide some insight?
     
  4. Ron Stimpson

    Ron Stimpson Stunt Coordinator

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    I have NEVER seen a receiver, no matter how cheap or how old that could NOT power one of our "4 Ohm" CS subwoofers fantastically.
    Keep in mind a few things. First, subwoofer transients are fairly fleeting. The can draw ALOT of power, but only for bursts. Also, an impedance of any driver is something of a nominal rating. The actually impedance/draw is very dynamic and will vary by frequency. You will usually have a higher than 4 Ohm load.
    Nearly any commercial gear can handle the limited requirements of a woofer like the CS, and as already noted, an amp rated at 100 watts into 8 Ohms will provide far more than this into a CS sub. You do need to exercise some restraint as you set up and calibrate a system with a receiver as the sub amp but really it's childs play.
    Tom did a good bit of listening with a PAIR of 25-31CS subs driven by a $80 KLH stereo receiver (the cheapest thing he could find at the time for this test) and with "only" a 100 watt rating it blew him away. Certain you are not going to max out the capabilities of the CS line this way, but as long as the amp/receiver doesn't get too warm and shut down you can expect to get a lifetime out of such a rig.
    A spare channel of a Denon receiver should do fine as long as you can figure out the signal routing (with pre-outs and low level ins etc.). With excellent used amps going for so little though you might consider just finding something like and old Carver, SAE, Soundcraftsmen, etc too.
    There are countless old stereo amps/receivers that are begging to get a second life out of them, this is the main reason we make the Cylinder Series subwoofers!
    Ron
     
  5. Joseph Kim

    Joseph Kim Agent

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    Purnam,
    I know the 3801 has 7.1 channel (6 channel 8 channel external input) input for an outboard processor, and I know it has pre-outs, but I'm pretty sure it doesn't have main-ins. I know my 4800 doesn't. So how would you hook up a passive sub to the reciever? Now on the other hand, you could use your sub pre-out on the reciever and hook it up to one of the channels on your acuras. I may be wrong, but just make sure you can do it on the 3801.
    joe
    [Edited last by Joseph Kim on August 06, 2001 at 06:46 PM]
     
  6. Nicholas A. Gallegos

    Nicholas A. Gallegos Stunt Coordinator

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    Hmmm, correct me if I'm wrong, but wouldn't the amplified terminals for the front and center channel speakers be completely overriden (i.e. disabled) if you were already using the pre-outs for those same channels?
    Even if what you wanted to do did actually work, you'd have to set the receiver to route the LFE signal to the main speakers (seeing that these would be ones your sub would be attached to). This would effectively route the LFE signal to ALL mains (even the ones attached to your power amp).
    I would be a lot simpler (albeit more expensive) if you got a separate monoblock to power your CS. But if want a pre/pro setup, I would actually just invest a 5-ch. power amp and be done with it.
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  7. Purnam

    Purnam Auditioning

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    Thanks for all the advice....I'll have to look more at this feasibility.
    cheers,
    Purnam
     

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