Using a MAC4200 as an amp?

[70sMac]

Mac Board..... Although I thought about adding this question to another thread I participated in, I think that it's a better idea to open it up to the board.

As you can see (below), the MAC4200 seems to have been designed for both stereo and mono operation. We presently use ours to power a pair of B&W N805s in a pseudo-surround setup that involves the HALL MODE surround function on our Mac MX-130. In short, it delays the audio signal between our fronts (B&W N802s) and our rears (said N805s).

That being said, I have to assume that it can be used as a fully independent power amp. I realize that 75W into 8 ohms isn't earth-shattering amplification, but, when money is short, you've got to make the best out of what you've got.

Long story [a bit] shorter, we have a Mac MC300 to power the fronts in a 5.1 surround setup. Theoretically, we have the MAC4200 to power our rears in the same setup...so, if we can employ our receiver in this way, we're only lacking one channel of amplification, right?

We also need a modern pre-pro, but I'm trying to focus on one subject at a time: and the topic for this thread is amplification. If anyone would care to add their thoughts on the pros and cons of using our MAC4200 as an independent 2-channel amp (or otherwise), we would be very grateful for the guidance.

Thank you very kindly for your time ~ B&J

Specifications (Partial) for the MAC4200 Receiver

[Yamaki]

-The MC300 will do a good job of powering those N802 speakers. I don't see you replacing the amp or the speakers as there is no need to and your money will be better spent on what's needed for that 5.1 theater sound you are looking for. Sure, the amp driving the N802 speakers could be a bit more powerful but 300W is more than sufficient even at higher levels. Just don't turn it up to 11, OK?

-Given that you have something to drive the R & L main speakers in hand, I'd focus on amplication for the center and R/L rear surrounds and I perceive therein lies your question. The most important of the 3 positions is, IMHO, the center channel. That speaker carries most, if not all, of the dialogue and amplification for that channel is and is also key in conveying some of the background and special effects reproduction. The rears are important, for sure, but have a secondary role in 5.1 channel sound reproduction.

-You might use the AVR you pick be your amplification for the center and rear channels but you probably won't find an AVR that can power that HTM3S center channel sufficiently.

Alternatives:

-An alternative to powering all 3 of those center and rear speakers is to let the AVR power the rear channels and you get a monoblock capable of 200W - 250W @ 8 ohms to drive the center channel. That way you can give that HTM3S some power to achieve very clear dialogue and clear special effects by having sufficient power.

-You could trade in the MAC4200 for a monoblock amp that will power that center channel.

-You could trade in the MAC4200 for a multi-channel amp that has sufficient power for all three channels, such as the MC8207.

I assume the MX130 sends the audio signal to the MAC4200 currently?

[70sMac]

Originally Posted by Yamaki

-The MC300 will do a good job of powering those N802 speakers. I don't see you replacing the amp or the speakers as there is no need to and your money will be better spent on what's needed for that 5.1 theater sound you are looking for. Sure, the amp driving the N802 speakers could be a bit more powerful but 300W is more than sufficient even at higher levels. Just don't turn it up to 11, OK?

-Given that you have something to drive the R & L main speakers in hand, I'd focus on amplication for the center and R/L rear surrounds and I perceive therein lies your question. The most important of the 3 positions is, IMHO, the center channel. That speaker carries most, if not all, of the dialogue and amplification for that channel is and is also key in conveying some of the background and special effects reproduction. The rears are important, for sure, but have a secondary role in 5.1 channel sound reproduction.

-You might use the AVR you pick be your amplification for the center and rear channels but you probably won't find an AVR that can power that HTM3S center channel sufficiently.

Alternatives:

-An alternative to powering all 3 of those center and rear speakers is to let the AVR power the rear channels and you get a monoblock capable of 200W - 250W @ 8 ohms to drive the center channel. That way you can give that HTM3S some power to achieve very clear dialogue and clear special effects by having sufficient power.

-You could trade in the MAC4200 for a monoblock amp that will power that center channel.

-You could trade in the MAC4200 for a multi-channel amp that has sufficient power for all three channels, such as the MC8207.

I assume the MX130 sends the audio signal to the MAC4200 currently?

Yes, Michael, the MX-130 is presently the "heart" of all things audio in our house, including the delayed "hall mode" signal that's being amplified by our MAC4200.

Do you mind if I ask for a few more details about why you would trade the MAC4200 for something else?

I recall the first time I ever heard a piece of Mac gear. It was a MAC4100, just like the one we own, and it practically shook things off of the book shelves via a pair of Altec-Lansing studio monitors. In fact, the guy who owned the receiver was quite proud of the Power Guard (PG) circuitry: and he showed me why...In short, that PG protection demo is the reason we own Mac gear.

The point is that, even at 75W per channel, the power amp in the old MACXXXX receivers can rattle one's ear drums; hence, my thoughts on using the MAC4200 as a rear channel amplifier.

[Yamaki]

My rationale for trading in the MAC4200 is simply one reason... More Power!

[70sMac]

Originally Posted by Yamaki

My rationale for trading in the MAC4200 is simply one reason... More Power!

Gotcha, Michael, I definitely understand where you're coming from.

[Yamaki]

Such a glib answer is of no help to you, Bill. Sorry about that... So here is reasoning that was behind that reply.

Your HTM3S deserves power beyond your MAC 4200's ability to provide. That's not a knock on the unit but not every McIntosh unit can drive that speaker well.

A more powerful amp driving that speaker will enhance your movie experience. The center channel impact to the realism of a well mixed production is a substantial one. I firmly believe powering that speaker with an amplifier of the proper specification will be well worth the money spent.

[70sMac]

Originally Posted by Yamaki

Such a glib answer is of no help to you, Bill. Sorry about that... So here is reasoning that was behind that reply.

Your HTM3S deserves power beyond your MAC 4200's ability to provide. That's not a knock on the unit but not every McIntosh unit can drive that speaker well.

A more powerful amp driving that speaker will enhance your movie experience. The center channel impact to the realism of a well mixed production is a substantial one. I firmly believe powering that speaker with an amplifier of the proper specification will be well worth the money spent.

Michael..... I didn't take your response as being insincere at all. As I mentioned previously, 75W per channel isn't much power, especially when one considers the type of speakers we're using. I never really thought of the MC4200 as being the ideal power amp, I was simply thinking about using it as a "pinch hitter" until we can free up some funds. Please stick with us.

[damacman]

Keep in mind that the specs in right hand column of the cropped photo are the specifications of the tuner in the 4200, not the amplifier. The internal amplifier is stereo only.

[70sMac]

Originally Posted by damacman

Keep in mind that the specs in right hand column of the cropped photo are the specifications of the tuner in the 4200, not the amplifier. The internal amplifier is stereo only.

DaMacMan..... I wasn't really thinking about using the MAC4200 as a mono amp. I was thinking about using its power amp section as a 2-channel amp for our B&W N805 rear speakers. In a way, that's what it's being used for now, but I wanted thoughts on using it in a 5.1 surround setup.

If we can use it in this way -- at least temporarily -- we will only be short by one channel of amplification. We've seen some mono amps that seem to be pretty reasonably priced, so I trust that you understand why we're looking at all the possibilities.

[70sMac]

Mac Man..... As I have no other way of contacting you -- other than to hope that you read one of our threads -- I want to ask you a different question: If you were looking for a [used] multichannel power amp -- and you didn't have a fortune to work with -- which one would it be?

I'll qualify this question, a bit, by stating that we believe that 120W per channel into 8 ohms is the bare ragged minimum for our speaker group. You strike me as a Mac expert and, quite frankly, that suits both of us right down to the ground. We love our boat anchors, so please don't hesitate to suggest the old solid-state Mac gear. By the way, please don't hesitate to mention some of the older units to stay away from, either. We've looked at couple of Mac MC-7104s, for example. They look quite robust to us, but 100W into 4 ohms? That's simply not going to cut it with our stable of B&W 8 ohm speakers.