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Two PowerAmps as monoblocks?

BTC3

pfm Member
Hi all
Wonder if I could have the benefit of your wisdom and experience, please?
My current set up uses a dac as pre-amp, connected to a Rotel rb-1552 mk2, and into some b&w DM2 speakers (which have single connection posts leading me to think bi-amping isn’t going to be possible).
I’ve been offered a second, identical amp by a friend who’s emigrating, and while I’m happy to help clear their stuff, I’m trying to work out what to do with it. The dac has balanced XLR outputs, and the amp the corresponding inputs, could I just wire up an amp for each channel? Am I likely to notice any difference/improvement in sound?
Thanks
 
I am thinking that, if you want to maintain a stereo image you have to wire each left hand output of each amp to the left speaker and the corresponding action for the right channel. But wouldn't you be doubling the current to each speaker? And wouldn't it possibly create a feedback from one amp into the other? Needs someone cleverer that me to answer your question.Intuitively something sounds wrong about it, as in...."Don't cross the streams !! "


 
The DM2's have a low sensitivity but the Rotel is a powerful amp and should drive them with ease.

I would say it is unlikely to make any noticeable difference.
 
I was intent on trying this some years ago with a pair of nap 250s I rang Dave at flashback to make me up a cable and he talked me into bi amping them ie using 1amp for the tweeters and I amp for the bass drivers. Really nice and they were old chrome bumper amps that had never been serviced well worth trying imho cheers Paul
 
I was intent on trying this some years ago with a pair of nap 250s I rang Dave at flashback to make me up a cable and he talked me into bi amping them ie using 1amp for the tweeters and I amp for the bass drivers. Really nice and they were old chrome bumper amps that had never been serviced well worth trying imho cheers Paul

How did the wiring at the speaker end work, were there two sets of posts? I had assumed that since my speakers only had two posts, not four, per speaker, bi-amping in the way you suggest was not possible.
 
How do you bi-wire a speaker with a single set of connectors?

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Interesting; thought any speaker was bi-wireable (depending on the amp), not that there'd be much or any benefit. Bi-ampable, though; different matter as possibly that's what the o.p. was toying with. Could be wrong, though.

As above /\. Any speaker can be converted to bi-wireable... at some expense and effort.. Hence I have bi-wireable Celestion UL6's and somewhere is a pair of MkI Spendor SP1's which are bi-wireable... 'cos I did it! Bi amping is bi-wiring with a separate power amp for each driver.
 
Interesting; thought any speaker was bi-wireable (depending on the amp), not that there'd be much or any benefit. Bi-ampable, though; different matter as possibly that's what the o.p. was toying with. Could be wrong, though.

The idea of bi-amping (one amp for the highs, the other the lows) was knocked on the head early on given the speakers aren’t made for it. Ditto bi-wiring, although past experience suggests to me it’s not that interesting. The idea here was to take two identical power amps, and have one drive the left speaker, the other the right.
The $64k question is whether there’d be any difference/improvement in sound quality. Answers here would suggest not.
 
The OP Question was about MonoBlocking, not biamping. So.. The important question is:

Can the Rotel amp be bridged to become a single channel monoblock?

If they can then it is do-able. I am not at all sure that you would see much benefit - you are only adding a few db of headroom on musical peaks and running more power from the main to do so.
 
The OP Question was about MonoBlocking, not biamping. So.. The important question is:

Can the Rotel amp be bridged to become a single channel monoblock?

If they can then it is do-able. I am not at all sure that you would see much benefit - you are only adding a few db of headroom on musical peaks and running more power from the main to do so.

They could be bridged or paralleled but if not built to do so (ie switches on the back to enable it) then it takes electronics expertise and there is some risk of damage as the some amps just don't like it and could go unstable and blow up....
 
I have been told by Emotiva that running a stereo amp as a balanced monoblock is possible, but some amplifiers just dont like it.

Yoy can buy or make XLR to to RCA adapters and try. Run the speakers from the two red terminals. Use at low power to minimize potential damage.

I have used this with tube buffers and it works fine. Power amps are a different kettle of fish.
 
I always think there is an effortless quality to large amplifiers driving speakers with just a fraction of their output. A lack of strain, an impression of lots of dynamic power in reserve.....
 
I always think there is an effortless quality to large amplifiers driving speakers with just a fraction of their output. A lack of strain, an impression of lots of dynamic power in reserve.....
I drive my Eminent Technology 8Bs with two monos per side, 600 and 1Kw.
 
just use one channel from each ampifier, less crosstalk.
... and “more power supply per single channel” (pls excuse the sophisticated terminology) : I did this with a pair of LK100 power amps & it worked well.
 


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