Bi-Amp workaround question

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RVJII
RVJII Posts: 167
edited November 2003 in Speakers
Question for bigsexy1 or one of you other really knowledgeable guys. I saw this on another post and wondered if it would really work. I've currently got a 7 channel (140 per) and am not using zone 2. I've got RTi12's bi-wired right now. Anyway, just wanted some comments on the below post:

"No, not the A/B functionality. If the HK AVR 8000 has multi-room capability (i.e., zone 2), then you can use those two amps to biamp your Rti150s. From here on out, multi-room = zone 2. Since you can select what the source is for the zone 2 independently, you can actually biamp your RTi150s using your receiver. Here are some fundamental steps for doing so:

1. Connect just the top posts of the RTi150s to your receiver.
2. IMPORTANT! Remove the jumpers between the top and bottom posts on your speakers.
3. Run a preout from the front channels to any unused input (I use the tape input).
4. Select this input as the source for your multi-room/zone 2 input. This may require you to select these amps to be used for zone 2 instead of rear surround, as they can be switched.
5. Connect the bottom posts of your RTi150s to the zone 2 outputs.
6. Enjoy twice the amount of power you were getting before.

I am leaving out one crucial step, however. And that is calibrating the zone 2 volume to match your receiver's volume. On mine, this equals a -2 dB setting (I believe) on my zone 2. It takes a little more typing to go into how to do this. But here's a big hint: it involves hooking up your speakers to the front exclusively, and then to the zone 2 exclusively, comparing the volume, and making adjustments to the zone 2 level to match. Thankfully, you'll only need to do this once. Let me know if you need more detail.

The only caveat with biamping in this fashion is that you must turn on multi-room when you switch on your AVR to get any bass. It's not a problem really, just an extra step. I have macroed my remote to do this on startup, as well as shutting off the zone 2 on shutdown.

As I said, I do this with my HK 525 and it works wonders. Hope this helps."
A lack of planning on your part does not constitute an emergency on my part...
Post edited by RVJII on

Comments

  • HBombToo
    HBombToo Posts: 5,256
    edited November 2003
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    I have the h/k 520 and have never thought of this configuration. Pretty damn clever in my opinion. While reading through it I was thinking what a pain it would be everytime you fire the h/k you would have to turn on zone 2 but the writer worked his way through that also. Good job to whomever wrote that!

    BTW I am a believer in bi-amping and am on the side that thinks bi-amping is more effective than bi-wiring for what its worth.

    HBomb
    ***WAREMTAE***
  • EnoughOfThis
    EnoughOfThis Posts: 10
    edited November 2003
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    In response to RVJII, it does really work. Like I stated in my original post -- I have been using this configuration on my HK 525 for some time now. Try it, and enjoy!
  • bigsexy1
    bigsexy1 Posts: 557
    edited November 2003
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    Note: I've never actually did this myself, as I haven't ever really had too, but if the situation was right, I would do it in a hearbeat. If you have a receiver with 7 powered channels, of which you are only using 5 of them, and your mains are biampable/biwireable, it would be almost foolish not to take advantage of this. Especially since it is so easy to do and virtually free. Plus, there will be no gain difference issues whatsoever to worry about by doing it this way.


    It CAN be done, at least on a Denon 5803 (and I would assume, on a 3802/3803 and 4802 also in the same manner) as follows:


    Bi-Amping on a Receiver?

    You betcha! True all of the benefits of bi-amping cannot be realized without eliminating the passive crossovers in the speaker system and actively bandwidth limiting the signals line level, but adding more clean power to a system is usually a good thing and something I happily welcome. The initial phase of my listening tests were to be conducted in 2 channel and 5.1 multi-channel surround and audio. I thought to myself, why let those two hulking 170 wpc amps that would normally power the back surround channels go to waste. I figured I could simply route the preouts of the main channels into the pre-ins of the rear back channels and boost my headroom by 3dB for the front channels and go to bed with a smile on my face that I had a receiver pumping 340 watts to each of my main speakers.



    Well it didn't quite turn out that way as Denon did not provision preamp couplers for this task. A quick phone call questioning “why?” to Denon's fabulous tech support revealed that they did this for a very good reason, eliminate a path for noise. Ordinarily I would have questioned that, but the very fact that year after year, Denon products, namely their receivers and DVD players always measure some of the lowest noise floors in the industry as illustrated by their exceptional Signal to Noise (SNR) measurements in all modes of operation conducted by various audio publications.



    After some thought, Denon tech support gave me the info on how to accomplish the bi-amping task. Here is how to do it. Note this will only work if you don't plan on using the amps for surround back channels or multi zone 2 applications.



    Bi-Amp Configuration of Main Channels

    Step #1: Connect a pair of analog RCA cables from the preamp outs of the “Front” channels to an unused input of the AVR-5803 (In my case, I chose VDP).

    Step #2: Select the chosen input as the source for Multi Zone 2.

    Step #3: In the Multi Zone Control menu, select power amp assignment for “Multi Zone 2”.

    Step #4: Using the internal test tones of the AVR-5803, position the SPL meter (slow response,
    C-weighted) at the listening position and increase the master volume control until each speaker
    reads about 75dB.

    Step #5: Disconnect the speaker level connections from the “Front” channels at the AVR-5803 and
    reconnect them to the appropriate “Multi Zone 2” speaker level connections.

    Step #6: Repeat Step#4 while varying the “Multi Zone 2” volume level. I found nearly unity gain
    correlation between the “Front” channel and “Multi Zone 2” amplifiers to be at the “Multi Zone 2”
    volume level setting of +2dB.


    Note: It would have been nice if the channel trim for this volume level control had +/-0.5dB precision, as all of the other channel trims of this receiver had, for better precision. Better yet, it would have been even nicer if Denon had a unity gain strap for this exact application so I could have avoided the pains of this set-up. Hint Hint. During my operation of the receiver in this set-up, I was always a little concerned if the wife or my daughter were to accidentally press a few wrong buttons on the remote and screw things up. However, if I couldn't audibly notice if this problem occurred, then I probably didn't deserve to worry about it.



    Step #7: Remove the jumpers on the back of the main speakers (you would be amazed at how many people forget to do this, Yikes!)

    Step #8: Connect a set of wires from the “Front” channels of the receiver to the highs section of each of your front speakers and a set of wires from the “Multi Zone 2” channels of the receiver to the lows of your front speakers.


    All of the basic audio calibrations were now complete, with a sign if relief, I was filled with anticipation to begin my subjective listening testing of two channel and 5.1 multi channel audio.



    BTW RVJII, refresh my memory here, what receiver do you have? Is it a HK 7200? Or a Denon 4802 maybe?
  • RVJII
    RVJII Posts: 167
    edited November 2003
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    I've actually got an Onkyo TX-NR900 7.1 (Used to be an HK fan until my last one...enough said.)

    I've got the RTi12's as mains with the CSi5 and FXi3's on order. Went with the FXi3's rather than the FXi5's due to availability in white. For a surround speaker (roughly 15% of HT audio) I can't see it making a huge difference. (5.25" vs. 6.5" driver is the only difference.)
    A lack of planning on your part does not constitute an emergency on my part...
  • RVJII
    RVJII Posts: 167
    edited November 2003
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    bigsexy1...

    If I did choose to go with a true bi-amp approach, any suggestions as to what would match up well with my Onkyo?
    A lack of planning on your part does not constitute an emergency on my part...
  • bigsexy1
    bigsexy1 Posts: 557
    edited November 2003
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    I would say the Onkyo M282, I think, is the model #. 100 watts per channel X 2.
  • ohskigod
    ohskigod Posts: 6,502
    edited November 2003
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    i dont think you can get the m282 anymore (unless used). you can get the INTEGRA ADM 2.1. its the same as the m282 (better cuircutry inside supposedly). I use one to power my surround channel, and sometimes use it in 2 channel mode as a spare system when needed. I can say it is a sweet sounding amp for its 300.00 price tag. I dont think there is a 300.00 amp new that can touch this thing. might want to consider it.
    Living Room 2 Channel -
    Schiit SYS Passive Pre. Jolida CD player. Songbird streamer. California Audio Labs Sigma II DAC, DIY 300as1/a1 Ice modules Class D amp. LSi15 with MM842 woofer upgrade, Nordost Blue Heaven and Unity interconnects.

    Upstairs 2 Channel Rig -
    Prometheus Ref. TVC passive pre, SAE A-205 Amp, Wiim pro streamer and Topping E50 DAC, California Audio Labs DX1 CD player, Von Schweikert VR3.5 speakers.

    Studio Rig - Scarlett 18i20(Gen3) DAW, Mac Mini, Aiyma A07 Max (BridgedX2), Totem Mites
  • ohskigod
    ohskigod Posts: 6,502
    edited November 2003
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    it is supposed to be an exact tonal match to the integra dtr 7.1 reciever. (i;m sure you know this, but integra is a spinoff company of onkyo, from onkyo's old integra line.)
    Living Room 2 Channel -
    Schiit SYS Passive Pre. Jolida CD player. Songbird streamer. California Audio Labs Sigma II DAC, DIY 300as1/a1 Ice modules Class D amp. LSi15 with MM842 woofer upgrade, Nordost Blue Heaven and Unity interconnects.

    Upstairs 2 Channel Rig -
    Prometheus Ref. TVC passive pre, SAE A-205 Amp, Wiim pro streamer and Topping E50 DAC, California Audio Labs DX1 CD player, Von Schweikert VR3.5 speakers.

    Studio Rig - Scarlett 18i20(Gen3) DAW, Mac Mini, Aiyma A07 Max (BridgedX2), Totem Mites
  • RVJII
    RVJII Posts: 167
    edited November 2003
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    I guess my next question is, can you "slave" the zone 2 volume control to zone 1? Otherwise you are going to have to adjust 2 independent controls each time you make a change.
    A lack of planning on your part does not constitute an emergency on my part...
  • EnoughOfThis
    EnoughOfThis Posts: 10
    edited November 2003
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    Since you are using the preout from the front channels as input into your zone 2, you will not need to do any independent volume control. Only during the initial setup will you need to touch the zone 2 volume.

    EOT
  • Ceruleance
    Ceruleance Posts: 991
    edited November 2003
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    man, who doesn't have 7.1 by now anyways? get on the bandwagon!
  • RVJII
    RVJII Posts: 167
    edited November 2003
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    EOT...thanks for the information.

    FYI: I do have a 7.1...so, I guess that I am on the bandwagon.
    A lack of planning on your part does not constitute an emergency on my part...