B&W DM605 S2 biamp?

[Blaa]

I was wondering would it harm my speakers in any way if I biamped my B&W DM605 speakers?

I just got a new receiver Denon AVR-3806, and here I have an option to biamp the front speakers. And I want to try this but not if it harms my speakers in any way..

[Stoney]

Blaa; I also have a pair of 605 S2. I would be interested in knowing how they are wired internally. They have two sets of binding posts so bi amping would be possible and, as far as the speakers are concerrned, there would be no more possibility of damaging them than if you used one amp or bi-wired them. I wonder how the built in sub would work? Have you ever listened to them with the sub power off? All bass and what seems to me as most mid range drops out. I am assuming the crossover to the mid range is very high since a lot of the mids and all of the bass is cut out when the sub amp is powered off. If that is the case, a lot of the mid and bass frequencies are being handled by the internal amp and I wonder if bi-amping would be a waste of the external amp used for the lows. I wonder if an e-mail to B&W asking these questions would be answered?
Anyway, to answer your question, I don't think you would damage the speakers, but it may be wasted effort bi-amping if the internal amp does the low and mid work anyway.

[Stoney]

Have sent this to B&W through their web site.

Regarding DM605 S2. What are the crossover frequencies? What frequencies are handled by the internal amp? What would the effect of using a Bi-amp configuration with these speakers?

[asrovnal]

Hi Blaa, I have a Denon 3806 and have my 703s bi-amped as directed in the manual using 40hz as the sub woffer setting. Be sure to select mains+LEF. Had them bi-wired which was of little or no value. Bi-amping and selecting a crossover setting for your speakers should open them up - they still paly there designed low freq's and the sub woffer picks up the remainder. Most noticable on 2ch listing, there is more on the cds then one thinks.

[Stoney]

Are the 703's also internally amped? The 605's have an internal amplifier that drives the two low freq. speakers.

http://www.bwspeakers.com/downloadFile/speakerModel/DONE-product_info_DM605S2.pdf

I am not sure if the two sets of binding posts would drive the Mid and tweet or if most of the frequencies on the low set of binding posts would be directed through the internal amp.
The top set of posts is labled HF and the bottom LF/MF.
The manual lists the crossovers at 230 & 4kHz. Does that mean everything below 230 is going through the internal amp? Then it would be kind of useless having a separate amp driving the internal amp. Basically the system is bi-amped allready with the internal amp driving the mid/bass and your external amp driving the highs.

[Stoney]

By the way asrovnal, I'm also in Rio Rancho. Small world!

[asrovnal]

1. Not to my knowledge. 2. How do the 605 get there power via a power cord or through speaker wire. Not a smart a.... question, I just have never seen a pair of 605s.

I was just about to ask that - drop me a private line I think that is possiable through this forum but I have never done it. Tony

[Stoney]

Sorry, I edited my post above a few times.
Yes, the 605's have a plate amp powered from the wall socket.
You can send a PM by left clicking on my name.

[Blaa]

I've spoken to B&W England, and I was told that the two lo-frequenzy woofers are only connected to the internal amplifer. The amplifer have both hi and lo level input, high level throught the speaker terminals and lo level through the RCA inputs.

So the lo freq woofers will only be fed with the power from the internal amp, 130W at 8 Ohms. While the tweeter and midrange are normal passive speakers. So if you give these speakers 200W in you'll give the tweeter and midrange 200W while the two active woofers will get 130W from the internal amp. This might lead to the speakes beeing a little top heavy.

I've biamped my Denon 3806 and feel that I got much more clearity in the sound that way, and since I also have the ASW2500 subwoofer I don't mind that the active speakers are just 130W..

I feel that this was written in a very sloppy type of language, but please forgive a Norwegian..

[Stoney]

Good to hear that you got an answer back from B&W.
I bi-wired mine from a Denon AVR-3801 and felt I got more clarity and better separation, but it may have been more due to the new cables than the bi-wire itself.
Did B&W happen to mention what the crossover to the mid and tweet are? When I switch the internal amp off, it sounds like a lot of the mids drop out also. I'm not really sure what sounds fall below the 250z crossover point that they list in the manual.
I have been wanting to place a bung in the flowports of mine to see if it cures some of the room resonances I get that cause some boominess when listening to two channel music.
By the way- I see absolutely no problems with your English!