Bi-Amping the Denon 3805

[sschen]

Hi

I am interested in Bi-Amping the Denon 3805 to output 240W to drive my main speakers. I am new to HT and am having some problems following the instructions posted by Clint on his Denon 3805 review, specifically Step 4 & 6 outlined below:

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 #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. Coincidentlally, there is apparently a similar preamp gain structure between the AVR-5803 and the Denon AVR-3805 as they both reached near unity with the Zone 2 volume at this position.

Step 4 refers to internal test tones of the AVR-5803, I guess Clint means AVR-3805? I don't have a SPL meter, I guess there is no other way for me to do this until I get hold of a SPL meter? Can someone kindly explain step 4 & 6 in lame man terms.

Clint also mentions the following:

Be sure to remove the jumpers on the back of the main speakers and then 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. Voila! You now paid only $1200 for a receiver that gives you 240 watts per channel to your main speakers where you need it the most.

I have a Dynaudio Audience 82. Since Dynaudio does not provide separate audio terminals for Bi-Wiring, is it okay to connect both set of wires from the "Front" and "Multi Zone 2" channels of the receivers straight to the audio input terminals of the main speakers?

Thanks
Stephen

 

[djoxygen]

I have a Dynaudio Audience 82. Since Dynaudio does not provide separate audio terminals for Bi-Wiring, is it okay to connect both set of wires from the "Front" and "Multi Zone 2" channels of the receivers straight to the audio input terminals of the main speakers?

Yikes!

Part (most, IMO) of the benefit of biamping isn't just to get more power to the speakers, it's to let each amp work exclusively on a certain range of frequencies. And then each amp is dedicated to pushing only one driver of a 2-way system. You get no benefit besides a little loudness (doubling your amp power gets you 3db of (barely) audible volume increase), and I'm not even sure you'll get all that with the amps working in parallel (I'm no electrical engineer).

 

[Jason Coleman]

Stephen-

If your speakers aren't set up for bi-amping (separate terminals for low end and high end connected with a removable jumper) then you definitely do not want to try to bi-amp. This process is intended for bi-ampable speakers. I don't know for sure, but you might run the risk of damaging your 3805 and/or your speakers.

If you need more power for your speakers, get a beefy 2-channel amp.

Jason

 

[mtrycrafts]

Hi

I am interested in Bi-Amping the Denon 3805 to output 240W to drive my main speakers. I am new to HT and am having some problems following the instructions posted by Clint on his Denon 3805 review, specifically Step 4 & 6 outlined below:

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 #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. Coincidentlally, there is apparently a similar preamp gain structure between the AVR-5803 and the Denon AVR-3805 as they both reached near unity with the Zone 2 volume at this position.

Step 4 refers to internal test tones of the AVR-5803, I guess Clint means AVR-3805? I don't have a SPL meter, I guess there is no other way for me to do this until I get hold of a SPL meter? Can someone kindly explain step 4 & 6 in lame man terms.

Clint also mentions the following:

Be sure to remove the jumpers on the back of the main speakers and then 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. Voila! You now paid only $1200 for a receiver that gives you 240 watts per channel to your main speakers where you need it the most.

I have a Dynaudio Audience 82. Since Dynaudio does not provide separate audio terminals for Bi-Wiring, is it okay to connect both set of wires from the "Front" and "Multi Zone 2" channels of the receivers straight to the audio input terminals of the main speakers?

Thanks
Stephen

What are you trying to accomplish here?

I think something is not right with the directions you were given.

First of all, I doubt you will get 240 watts a channel from that receiver. It is not so rated so you cannot.

By amping is not much of value without other considerations. You need a speaker that is capable of it. Even if it has two terminals on the back, one for low and one for high, you are still using the passive crossovers installed so all you would be doing is, as was mentioned above, is doubling power with is not much really.
To get the most benefit out of bi-amping is not to have a passive crossover but an active one to all drivers then driven by its own amp.

I would not consider it otherwisse.

Step 4 and 6 looks like level matching procedures.

 

[cam]

What are you trying to accomplish here?

I think something is not right with the directions you were given.

First of all, I doubt you will get 240 watts a channel from that receiver. It is not so rated so you cannot.

By amping is not much of value without other considerations. You need a speaker that is capable of it. Even if it has two terminals on the back, one for low and one for high, you are still using the passive crossovers installed so all you would be doing is, as was mentioned above, is doubling power with is not much really.
To get the most benefit out of bi-amping is not to have a passive crossover but an active one to all drivers then driven by its own amp.

I would not consider it otherwisse.

Step 4 and 6 looks like level matching procedures.

A familiar name, how are you doing mtrycraft. There is a great little feature on the 3805 that can enable you to bi-amp the mains. You first have to be using it as a 5.1 set up. The six and seventh channel can then be used to bi-amp your mains. It is a very difficult to understand procedure but rest assured the 3805 is designed to do such a thing. I don't have the 3805 but I have read about this feature in reviews before. I must have read the procedure half a dozen times and I still did not understand. I'm sure that if I had a 3805 in front of me I could figure it out.

 

[Jason Coleman]

The bi-amping process is difficult to understand while reading, but it makes sense when you're with your 3805 actually doing it. Once you've made all of the cable connections, to match the levels, simply use the remote and press Zone 2 and turn the volume up to +2dB. This seems to be the common number where people have found the lows and highs to balance out.

BTW, while I don't think the Denon was implicitly designed with bi-amping in mind, but it does do a hell of a job.

Jason

 

[gene]

Ok lets simplify the Bi Amping process by assuming we know the unity gain volume setting for the amps to be nearly balanced (+2dB):

Step #1: Connect a pair of analog RCA cables from the preamp outs of the "Front" channels to an unused input of the AVR-3805 (In my case, I chose the CD inputs).

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

Step #3: In the POWER AMP ASSIGN menu (5-1), select “Zone 2".

Step#4: Adjust the "Multi Zone 2" volume level to +2dB.

Step#5: Remove the jumpers from the speaker terminals of your front speakers.

Step#5: Connect the "Zone2" speaker level connections to the bass portions of your left and right front speakers and connect the "Front" speaker level connections to the mid/high portions of your front left and right speakers.

Step#6: Avoid confusion and overanalyzing this tweak in forums and enjoy

 

[Rob Babcock]

Make REALLY sure you do #5 on the list (well, the first #5 of the two! ) or risk something really nasty happening! Leaving the strap/jumpers on the speaker is any easy thing to overlook but will result in tears.

 

[mtrycrafts]

A familiar name, how are you doing mtrycraft. There is a great little feature on the 3805 that can enable you to bi-amp the mains. You first have to be using it as a 5.1 set up. The six and seventh channel can then be used to bi-amp your mains. It is a very difficult to understand procedure but rest assured the 3805 is designed to do such a thing. I don't have the 3805 but I have read about this feature in reviews before. I must have read the procedure half a dozen times and I still did not understand. I'm sure that if I had a 3805 in front of me I could figure it out.

I am well, thanks The previous place is changing too much so I may reside here until I am no longer welcome.

OK. now I see what they are doing, they are allocating other channels for biamping.
But as I posted further, not much of an advantage and after a few Tylenols to sooth the headaches figuring it out, one should give up?

 

[Unregistered]

don't

If your Dynaudios DO NOT have separate binding posts for bass and treble DO NOT CONNECT two separate amplification channels to the same terminals!! This will at the very least trip the protection circuitry and at worst fry your amp. Bi-amping/tri-amping is designed to work with crossovers which have totally separate circuits for bass and/or mid and/or treble. You would have to, in effect, re-work the crossovers and internal wiring and add a new set of biding posts on the back of your speakers or run the new wires through the bass port. This is do-able but you render your warranty useless. If your speaker's warranty has expired then no matter.

 

[barend]

Biamping

I obtained the best resultus by hooking up an extra amp i.e. Rotel RB981 to biamp the front bass sections.
Wonderful control and no power supply related power decrease.
Just feed the amp from the preouts and you're done.
BE CAREFUL BIAMPING WITH THE DENON INTERNAL AMPS!
Sometimes accidentally you adjust the ZONE2 volume instead of the MASTER VOLUME (Denon uses the same buttons on the remote and the same volume control on the fascia- stupid) only to find you blow a speaker gasket (so to speak).
This is why final amps have level controls on the rear or none at all...
(I can set the level of the Rotel with fixed 3dB RCA plug attenuators, but do not use the guitar amp sorts they're way too high impedance so attract hum).

And it may also be one of the reasons why Denon discourages biamping the 3805, besides the strange hum from the biamping channels.

Barend

 

[Jason Coleman]

Barend-

Have you actually heard that Denon is discouraging bi-amping? If so, what have you read/heard? Just curious how they are handling this.

Jason

 

[slmcdonald7]

surround A for bi-amping?

After I purchased my 3805, I called Denon's tech-support line to ask this very question (amongst others). On the other end of the line, the very polite and knowledgeable Tony recommended that I bi-amp them (I had previously mentioned in a different thread that he told me to "bi-wire" them, but I was confused on my terminology ), as he himself had done on the 3805 he used at home. I am not a representative for Denon (thus I can only speak for myself), but based on what Tony the tech said, even if they don't recommend it, they don't seem to be discouraging it.

Here's my twist on the 3805 bi-amping procedure line of questions...

In my discussion with Tony about this, I stressed that I wanted to use the zone 2 outputs for speakers in my office, and play them in conjunction with the bi-amped fronts. He suggested a way for me to do this using my surround A outputs (since I'm not using any surround speakers), but I don't remember the exact procedure he suggested, and I am too worried about blowing something up by doing it wrong.

Does anyone know how I could safely do this? Could I just follow the same procedure as used for bi-amping using the zone 2 outputs?

Also, once I bi-amp them with the surround A outputs, is there any reason I could not use my microphone for the "auto speaker set-up" function, or would I have to do it manually?

Thanks all,
Stephen

 

[mtrycrafts]

If your Dynaudios DO NOT have separate binding posts for bass and treble DO NOT CONNECT two separate amplification channels to the same terminals!! This will at the very least trip the protection circuitry and at worst fry your amp. Bi-amping/tri-amping is designed to work with crossovers which have totally separate circuits for bass and/or mid and/or treble. You would have to, in effect, re-work the crossovers and internal wiring and add a new set of biding posts on the back of your speakers or run the new wires through the bass port. This is do-able but you render your warranty useless. If your speaker's warranty has expired then no matter.

I am sure you meant this post to the original poster?

 

[djoxygen]

To all bi-amping:

Had a good discussion with a friend (who used to be my partner in recording studio) over the weekend about this stunt y'all are trying.

His thoughts paraphrased:

1) If you're amplifying the full range of frequencies upstream of the crossover (in this case the passive one inside the speaker box) the crossover is dissipating at least some of the amp's energy. (How much is math that's beyond us.) Bottom line: You're not getting the full 120+120 w.p.c. that you're hoping for out of this.

2) If you want to biamp the correct and complete way (active x-over) you'll almost certainly need to open up your speaker cabinet and bypass the internal crossover - there's no way to have the x-over auto-bypassed as with pro speaker cabinets. If you don't do this, you'll at the very least have a pronounced dip in FR if the crossover frequencies are the same between active and passive. If they're not set the same, you'll have very little energy in the frequency range between the two crossover frequencies.

3) Since there's a very small amount of consumer interest in biamping, there's little incentive for speaker mfrs to design easily bypassed passive cross-overs and for electronics mfrs to make active crossovers for use in HT systems.

(I'm cross-posting this in the "Tripp Lite Isolation Transformer" thread as well. Even though this is probably a better place for this discussion, there's a lot about it over there.)

 

[Jason Coleman]

DJOxygen-

I don't really think that anybody was expecting to get a full 240 watts (120 wpc x 2) through bi-amping. First of all, the Denon can't put out 120 wpc. Secondly, it's a no-brainer that you won't get the full 120 wpc (even if they were there) to both the highs and the lows.

This being said...this so-called "stunt" (I only quote it because this is how you have referred to this process twice that I've seen) has made a drastic improvement in my system and many others' as well. While we aren't doubling our power to our mains, we are increasing the power to each section and we are able to adjust the amount via the Zone 2 volume level which is actually a pretty damn cool option that you wouldn't normally have in a traditional setup. The bottom line is this...the bi-amping is a decent way to get some additional power out of the 3805 in a 5.1 setup...you can balance the sound out as you like with precise control over the low vs. high levels...the process only takes a pair of cables and about 10 minutes to do...etc. Is it "true bi-amping?" No. Do I really care when it makes such a noticeable improvement to my setup? No, again.

I'm not trying to be defensive, I'm just suggesting that you at least try it or see it done before passing such sweeping judgment. Maybe peek around at other forums and see what they have to say. Not many people at Audioholics seem to have tried it.

Jason

 

[djoxygen]

Likewise, I wasn't trying to be "offensive". My use of "stunt" is meant to indicate that this procedure isn't found in any user manuals and people who want to attempt it should be aware of all potential effects, both positive and negative.

If you are happier with the sound now than you were before, then you should keep your system rigged this way. Others should decide for themselves. I am a *huge* advocate of bi-amping, and all four of my monitors are actively bi-amped.

As long as everyone trying it is reading all available information here and elsewhere, (i.e. not trying it with speakers that have only one set of binding posts, not expecting a doubling of power, etc...), then no harm will be done.

 

[Audioholics]

Updated Denon AVR-3805 Biamping Instructions

Due to an inordinate amount of confusion resulting from the biamping instructions within the Denon AVR-3805 review we have removed them - JUST KIDDING.

We did, however, update the instructions for simplicity and to lessen the daily torrents of emails regarding this hidden "feature".

Enjoy!

 

[happy540i]

djoxygen is right. The correct way of bi-amping your system is by getting the output from the pre-outs, then it goes to an active crossover, then it goes to separate power amps, and finally your speakers. That's how I'm doing it with my Denon 5803A. I have M&K Pro speakers and it allows me to do that. You will get a much better sound with this setup.

 

[gene]

Happy that is correct. But our tweak is meant for the average joe who wants to easily utilize the extra 2 amps in their receiver to perhaps improve the performance of the system slightly.