Bi Amp or Dual Monos

[JMac]

I'm currently running 2x MF M1PWR amps in mono mode so that each amp sees the one speaker. However, I'm thinking of switching them stereo mode and buying two more runs of speaker cable and giving them a try bi amp'd. What would peoples expectations be, better, worse or no difference?

 

[Al ears]

You don't mention speakers that they are connected to.

In my opinion you already have them connected in the best configuration and probably would not hear any difference connected otherwise. Better to spend funds on more music *biggrin* or, indeed, imporove your pre-amp (which you fail to mention).

 

[Vladimir]

This way you are providing all of the amplifier power reserves for the speakers to 'decide' how much each driver will take (the bass units will certanly eat over 80%). If you split the power reserves 50% available for HF and 50% for LF, the bigger watt guzzling drivers may end up lacking power.

Dual mono bi-amp: 50% (one amplifier) of total power available per speaker.

Stereo bi-amp: 25% (one amplifier channel) of total power available per HF/LF section.

This may or may not make an audible difference, depending on the speakers. They are the boss in your system, the amp is just a reservoir.

 

[davedotco]

Using stereo amplifiers in dual mono mode usually means that some form of bridging is taking place, this is fine except that the amplifiers 'load tollerance' is halved. Ie a stereo power amplifier that is optimised for 8 ohm speakers, when mono-ed will now be at it's best into 16 ohms.

The issue here is low impedence speakers, for the mono-ed amplifier to be capable of driving down to 4 ohm (say) the same amp in stereo would have to be capable of driving down to 2 ohms and few are.

Obviously the manufactures know this so are not going to fit a mono switch to an amplifier with poor load tollerance but it is generally best to avoid speakers with low impedences in such situations.

The Musical Fidelity rather fudges this information with unspecified power specs and suggests that in mono mode, the 200watt 4 ohm rating is "transient peak capacity", not rms.

Choose the right speakers though and it doesn't much matter, the power delivery will be substantial and providing you take on Vlads explanations earlier in the thread, both setups should work fine,

 

[JMac]

Pre amp / DAC is a MF SDAC, speakers are Tannoy DC6

The reason I was going to try it was that I read somewhere that amps with switching mode (stereo/mono) often sound better when run in stereo mode as that this is the main running mode for the speaker (i.e. most people will only use one amp running in stere) and designed this way as priority. The fact that they can run in mono is something of a lesser consideration.

 

[davedotco]

Pre amp / DAC is a MF SDAC, speakers are Tannoy DC6

The reason I was going to try it was that I read somewhere that amps with switching mode (stereo/mono) often sound better when run in stereo mode as that this is the main running mode for the speaker (i.e. most people will only use one amp running in stere) and designed this way as priority. The fact that they can run in mono is something of a lesser consideration.

This is sort of correct, but it is the way the stereo and mono-ed amplifier handle the speakers rather than any specific design criteria that makes the difference. Generally I do not think bi-amping in this way to be worth the effort and cost, but you have the amps so should gice it a go. Should be fun and it will broaden your hi-fi knowledge and experience.

 

[Vladimir]

Unless each block is true dual mono by itself, it's really pointless to do channel separation with stereo biamp. This M1PWR isn't true dual mono, it has a shared PSU for each channel. Only two of these amps each set for mono will consist a dual mono configuration. Otherwise you have nothing better than two normal integrateds biamping.

 

[JMac]

Thats what I do have, two of them switched to mono operation for dual mono. I was wondering if switching them back to integrated and running them bi amped would make an improvement but seemingly not.

I have also considered picking up two more and running four mono's so effectively one for each drive unit on the speaker as the amps can be picked up used for around £250-300 quid but I think I'd probably see more of an improvement in selling the existing two I have, throwing in the extra and getting an M6si or similar.

 

[Vladimir]

Going from dual mono with two amplifiers to biamped stereo or just normal integrated stereo is technically downgrading. If you find the stereo biamp sounding better, you most likely enjoy channel crosstalk, more distortion or just plain placebo. What you already have is excellent.

What is it that you find lacking in the sound you already have? Which speakers and preamp are you using?

 

[JMac]

Musical Fidelity M1 SDAC for DAC and pre amp and Tannoy DC6 stand mounts for speakers

It just seems to be lacking in overal dynamics, excitement, is a little bass light (not massively tho) and generally sounds a little 'flat' to me. Maybe I have unrealistic expectations or maybe I need to play around with sources and connections (the optical connection is supposed to work better than the USB on the SDAC) .

I have considered recently upgrading to the DC6T SE which are on offer at a lot of places right now as there some things I like about the Tannoys e.g. imaging, but I cant say I love them.

 

[Vladimir]

There is your bottleneck right there. Small speakers, excellent sound quality, but small.

Everyone has gone all obsessive over sonic details, as if you need to hear the conductor's freshly ironed shirt wrinkling in order to enjoy music.

What is first thing you notice when you go to a concert?

The immense POWER!

Blast of huge sonic energy making you gasp for air and driving you into tears. Experience bigger than your lowly self. A grand scale of artistic expresion and uninhibited emotional drive.

SPL. Sound Pressure Level.

 

[davedotco]

There is your bottleneck right there. Small speakers, excellent sound quality, but small.

Everyone has gone all obsessive over sonic details, as if you need to hear the conductor's freshly ironed shirt wrinkling in order to enjoy music.

What is first thing you notice when you go to a concert?

The immense POWER!

Blast of huge sonic energy making you gasp for air and driving you into tears. Experience bigger than your lowly self. A grand scale of artistic expresion and uninhibited emotional drive.

SPL. Sound Pressure Level.

Gosh.

When did you see the light Vlad.......?

 

[Vladimir]

Gosh.

When did you see the light Vlad.......?

 

[Al ears]

Gosh.

When did you see the light Vlad.......?

Nice..... is that a Cerwin Vega?

 

[JMac]

lol, and how do you balance that with room size and maximum distance available to sit away from the speaker?

 

[Vladimir]

When you need a good sound wallop for a private party or just simply to rock out, those CVs are you best bet. I also had these JBL Eon 15 to get my kinks. But those fun days are over.

Now, if you want large SPL with accurate,undistorted fullrange sound with fast transient response... that is not going to be cheap.

 

[Vladimir]

lol, and how do you balance that with room size and maximum distance available to sit away from the speaker?

Putting large well behaved and neutral closed box speakers in small room is better than using small bokshelf speakers with bass ports and huge midbass humps.

 

[davedotco]

lol, and how do you balance that with room size and maximum distance available to sit away from the speaker?

If you are worrying about things like that then you are missing the point.....*biggrin*

Seriously though, the whole lack of presence and impact that is the norm with most hi-fi can be a real problem for some people, I very much include myself in that.

In an ideal world I would have a big pair of 'foxtrot oscar' studio type speakers in an otherwise normal but decent room. I don't play very loud but I like a bit of presence.

Choosing hi-fi is about the compromises that you make to try and deliver a satisfying experience that is consistent with your living conditions.You might choose to play quietly, or simply not to play large scale classical or rock and roll at all, it depends on you.

A few years ago we spent a winter in our newly completed apartment in a block that was very sparsely populated, much of the time there was no-one close by at all. I played as loud as my modestly powered system could manage but really missed my old JBL 4333s.