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Using the 4100 as a preamp

Remove jumpers and run one RCA IC cable from each channel of the MAC's preamp outputs to each of the MC2200s. I believe the left input is used when the MC2200 is set up for mono parallel operation. Check the MC2200 manual for other connections/settings that need to be made.

Frankly, I question the reasoning behind arming the AR3a with 400 watts of capability when the 100 wpc (4 ohm) of MAC is already more than up to the task. It won't sound any better and this is a speaker that isn't designed to withstand anywhere near that kind of input. It's a fairly low sensitivity speaker so be careful with the volume control, especially since you'll be "flying blind" without meters. The PG of the MAC will limit power output to ~125 wpc (4 ohm) which is about the maximum the AR3a can handle- and only for short term peaks.
 
Thanks for the reply. I always read your posts with great interest.
I'm considering this only because a PAIR of 2200s have seemingly appeared, for what seems to be a VERY low price. I'm figuring, using the "Quantum Theory of Being Male", that more is better, especially at this price point (plus getting them back to spec). So... "Why not"? A 2205 or 2255 are actually my first choice. But the idea of all that brushed aluminum staring at me is appealing (2200s), maybe I'd just use one! But then again, you can't beat that Mac Blue and Meters!
 
So much for that idea... those amps are gone. When something seems too good to be true, it usually is. I would appreciate any further comment on upping the power a bit wit a Mac SS amp, be it metered or no.

Thanks.
 
ThreeWay said:
So much for that idea... those amps are gone. When something seems too good to be true, it usually is. I would appreciate any further comment on upping the power a bit wit a Mac SS amp, be it metered or no.

Thanks.
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It was God's way of saying just use the damn 4100. :biggrin:
 
damacman said:
Is it safe to assume that you are lighting the Power Guard lamps often when using the MAC4100 to drive your ARs?
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Ok, this gives me pause. I know its an old thread, but im bout to purchase a Mac 4100 receiver to run a pair of hungry AR 93S speakers. I thought 100wpc would duffice, but this thread makes me wonder. I didnt have any illusions of running my JBLs along as back speakers. Maybe i can amp it up later to add the power of the JBLs to the mix.

Still, everything i run the numbers thru, say the 4100 can drive the ARs. I hope thats the case.
 
If the numbers, 75wpc@8 Ohms / 100wpc@4 Ohms supports your use-case with your speakers, and the MAC4100 is properly serviced / operating as designed, there should be no worry. Typically McIntosh amplifiers can operate within the THD spec at 125% (or more) of rated power, and the PowerGuard lights indicate (IIRC) .5% distortion which should be at least 200% of spec (peaks) power, which only tells you that you’re beyond the ability of the amplifier section to provide enough power for your peaks and it is compressing those peaks to avoid significant distortion and the potential for speaker/amplifier damage.

You can pretty much drive any speaker hard enough to see the PG lights flash if that’s how you listen to music, It was designed to protect, and that it does, in most systems you wouldn’t notice anything until you get to audible distortion or smoke a tweeter in a McIntosh with PG you will see lights flash and probably not be able to hear the slight compression.
 
AR 93S specs show max continuous input of 125W; 87 dB sensitivity; 6 ohm impedance; 4.5 ohm minimum.

In real world testing, the MAC is good to 100 wpc into 8 ohm continuous; 120 wpc into 4 ohm. It's also designed to run up three pair of 8 ohm speakers at the same time which is only 2.67 ohm. Since it has PG circuitry, the amplifier can't be overdriven and the speakers are protected from clipping damage. It should be fine.
 
hamsterdam said:
Ok, this gives me pause. I know its an old thread, but im bout to purchase a Mac 4100 receiver to run a pair of hungry AR 93S speakers. I thought 100wpc would duffice, but this thread makes me wonder. I didnt have any illusions of running my JBLs along as back speakers. Maybe i can amp it up later to add the power of the JBLs to the mix.

Still, everything i run the numbers thru, say the 4100 can drive the ARs. I hope thats the case.
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There's much more to power amps than power output figures alone. As much as I like my MA6200 (let's call it a 4100 less the tuner), the power supply within it is multi-tasked. Whereas in a standalone power amp, the power supply is solely available for the amplifier. The more capable the power supply, the easier the amp can drive a wide variety of loudspeakers. Of course this adds cost.

I'll stray from the pack here - a 4100 wouldn't be my first choice for these speakers. Man, there are just so many choices for a McIntosh power amp that could run these speakers well - you may want to begin a new thread on it.
 
I'll say this...
When I got my near mint 4100 last year, it was to finally have a piece of McIntosh equipment in the rack I could afford. I was going "Vintage" and on a receiver jag. Only took about 50 years. I got it specifically to play vinyl and run my restored AR3a's and it sounded great - both the amp and the speakers. When an MC2150 showed up, I pounced, because more is better, Amiright? The combination of the 4100 pre and the 2150 also sounded great. No problems driving the AR's.
Life being what it is, I traded the 2150 on an MC2205, the 4100 for a mint MR77 and cash, and acquired a very nice C34V . The 2205 has been a 4 month litany of broken glass, shipping nightmares, ridiculous repair wait times, and dealer frustration. I get it Friday. As I have not blown my brains out over the whole mess, there will be a full report.
 

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ThreeWay said:
<<snip>>
Life being what it is, I traded the 2150 on an MC2205, the 4100 for a mint MR77 and cash, and acquired a very nice C34V . The 2205 has been a 4 month litany of broken glass, shipping nightmares, ridiculous repair wait times, and dealer frustration. I get it Friday. As I have not blown my brains out over the whole mess, there will be a full report.
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I recommend leaving the meter bezel in a safe place and running without it, I think it updates the 2205. I did that with the 2255 and really liked how it looked.

I have a feeling it’ll be worth the wait when you get to sit down and listen to the music.
 
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