Mc452 - multi taps outputs

[kurnitb]

Hi guys, this might be a silly question but would I be able use the the multi taps outputs for bi-amping? Thanks.

 

[Adam]

I don't know if you can do it, but the owner's manual and wiring diagrams make it clear that it's designed to only use one output terminal per channel. They show a bi-amped system using two MC452's.

 

[fmw]

Hi guys, this might be a silly question but would I be able use the the multi taps outputs for bi-amping? Thanks.

I have no idea but, since you ask, I have to guess you may not understand bi-amplifying very well. In order to bi-amplify speakers, you need to disconnect the crossover network inside the speaker cabinets and connect the drivers directly to an active crossover with an amplifier for each driver. It is very uncommon in home audio to do this and, for most applications, it is pointless. B&W is perfectly competent in the area of speaker voicing. I'll bet you would have a tough time improving on their work. Are you trying to combine two amps into each speaker? You have a monstrous amplifier. Assuming that drives your mains, you have way more power than your speakers can take without destroying themselves. What on earth do you want to accomplish?

 

[TLS Guy]

Hi guys, this might be a silly question but would I be able use the the multi taps outputs for bi-amping? Thanks.

Absolutely not. The taps are auto transformers for matching the amp to the load. Mac love the idea. I'm not sold on it and I'm certain it is inferior to a well designed direct coupled output stage.

Any way only one tap can be used at a time to balance one loudspeaker to the output stage.

To have any benefit from biamping, the passive crossovers in the speakers need to be removed, or the speaker designed for biamping form the ground up.

Then you need to design active electronic custom crossovers, or use achieve the same use units such as Mini DSP. Then you need an amp for every frequency band the speaker requires. That means two amps for a two way speaker and 3 amps for a three way speaker.

Biamping via the speakers passive crossovers, gets you no benefit, just expense and complication. It won't sound better and could well sound worse.

 

[markw]

Dude, bi-amping is done before the power amp, not after.

 

[PENG]

I am not referring to the question about using the taps, but to the responses about how biamping means disconnecting crossovers, done before the power amp etc. IMHO, it depends on how you define biamping. Until someone can show me that there is in fact a standard definition universally accepted by the industry, I would respectfully disagree with the notion that biamping means the internal crossovers must be disconnected/before power amp etc. As far as I know either way are referred to (or loosely defined if you like to call it that) as biamping, one being described as active the other passive. Whether biamping in whatever form improves sound quality is an old endless debate that I have no intention getting into.

 

[markw]

I am not referring to the question about using the taps, but to the responses about how biamping means disconnecting crossovers, done before the power amp etc.

I'd really like to see some, or even one, example where biamping is not done before the power amp stage. To say it's not implies it's done after.

 

[slipperybidness]

Absolutely not. The taps are auto transformers for matching the amp to the load. Mac love the idea. I'm not sold on it and I'm certain it is inferior to a well designed direct coupled output stage.

Impedance matching is certainly a very important concept.

However, you are certainly correct that there are better ways to go about it, like a well-designed output stage.

Is this Mac a solid state amp with impedance matching transformers??? WHY???

EDIT: Now that I look at some pics, it does indeed seem to be SS with impedance matching transformers. For that kind of $....doesn't make any sense.

 

[PENG]

I'd really like to see some, or even one, example where biamping is not done before the power amp stage. To say it's not implies it's done after.

So by "before", you meant connecting each power amp to the preamp using a Y connector? If so obviously I must agree. Whether external crossovers are used or not, both amps need to be fed.

 

[Irvrobinson]

Is this Mac a solid state amp with impedance matching transformers??? WHY???

EDIT: Now that I look at some pics, it does indeed seem to be SS with impedance matching transformers. For that kind of $....doesn't make any sense.

For the same reason the Corvette still has transverse leaf springs, the Porsche 911 still has a rear engine, chronograph wrist watches still have tachymeters, Accuphase pre-amps still have tape monitor loops and wooden cases, guitar amplifiers still use tubes... I could go on and on... because companies believe that some arcane technology or design choice is a part of their legacy and they're afraid to leave it behind, or they actually convince themselves they are positive differentiators. In the case of tube guitar amps it's probably more the customers than the suppliers, but the McIntosh's autoformers remind me more of the Corvette's leaf springs - do buyers really care?

 

[markw]

So by "before", you meant connecting each power amp to the preamp using a Y connector? If so obviously I must agree. Whether external crossovers are used or not, both amps need to be fed.

Yes, that was my meaning. Either with a a "Y" connector (passive biamping) or via an electronic crossover (active biamping).

This, as opposed to using the speaker outputs on the power amp as was the OP's original question/intent.

 

[PENG]

Yes, that was my meaning. Either with a a "Y" connector (passive biamping) or via an electronic crossover (active biamping).

This, as opposed to using the speaker outputs on the power amp as was the OP's original question/intent.

Sorry, I misunderstood.