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Which amps for new McIntosh ATMOS/DTS:x system?

S

scanido

Active Member
Hey All,

Would like some advice and your experience to help me put a finger on which McIntosh Models to get to expand my current HT from 7.1 channels to the next gen 7.1.4 based system.

I am currently constructing a dedicated cinema room and although I will continue to use my MX150 for a 7.1 system, I do plan on installing overhead speakers for a future 7.1.4 setup. So the issue i have is deciding on an ideal amplifier(s) to drive my center channel, and surrounds for the current planned setup and one that can expand to support later Dolby Atmos/DTS:X formats.

I currently have the following speaker setup:
B&W 802D2 fronts
B&W HTM2D2 center
B&W CWM8.3 surround
B&W SCMS rear surrounds

Driven today by 2x MC601 amps for fronts, and MC205 for the remainder.

I plan to get two pairs of B&W CCM682 for overhead channels as recommended by B&W. So I have the following end options:

OPTION 1
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- 2x MC601 for fronts
- MC303 for center, surrounds
- MC207 for rear surrounds, overhead channels

Therfore, would add MC303, and I would have to sell my MC205 for a MC207 for this setup.

OPTION 2
======
- 3x MC601 for fronts and center
- MC302 for surrounds
- MC207 for rear surrounds, overhead channels

Therefore, would have to add another MC601, MC302, and trade MC205 for MC207. This option is the most costly, and wondering if this is worth the expense considering the MC601 will be overpowering my center rated at 300w. Obviously this would be the ultimate setup, but will Option 1 suffice?

Thanks for your recommendations.
 
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I like Option 1. I've played around with Mc amps on the surround channels since before Dolby had "Pro Logic" - think David Hafler surround. I just don't think you need as much amp on the surround channels as what everyone proclaims.

FWIW, I'm also considering such an upgrade in the future. I'm looking at options for amplification as well . . .
 
You need as much power for the center if not more and its important to have have everything be equal as possible. So you need one 601 for the center. Then I would get another MC205 to match what you have now. You ought to to be able to find a 205 that's been pre owned and possibly a 601 if that doesn't rub you the wrong way. Then you would have two channels left over, for the future or in case one of your 601 crashes.
 
Any theater/presentation system needs to be designed from the center out if you have any expectation of getting paid. Passing the AllCons test was always a part of the contract. Without a prperly designed full range center "stack" you had no chance of getting it right.

Surround sound is like the sizzle of a steak presented in a good steakhouse.....yea the sizzle makes for a great presentation, maybe even fun, but if the steak is tough, it can't fix that.

Amateur home theater, without at the very least, 3 identical full range speakers across the front will always be a compromise.....

The B&W literature I remember always had 3 801s across the front......

Remember in pro theaters, where movies are designed to sound right, use dozens if not hundreds of surround effect speakers.
 
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I am going to use the MC8207 for the front, center and surrounds for my Atmos set up.

I really wanted the MX160 but since the unit keeps getting pushed out, I purchased a Marantz 7702 for now.

I am going to use a C2500 for music and use the bypass for home theater. My plan in the future is to get a dedicated two channel amp for music but will need to wait a while as we are in the middle of a home remodel.
 
Guys, let's get real here. Three identical speakers across the front with equal power simply isn't realistic in most domestic settings - nor is it necessary. I JUST watched Mad Max Fury Road in one of the nicest movie theaters in the state of AZ (Picture Show in Prescott, AZ). While the audio was indeed impressive (with exception of very low bass), my multi-channel system is equally as impressive in a far smaller environment.

I've always tried to have equal power for the center and surround channels. I've had up to 8 times as much power for the L&R, since they're also my 2-channel audio speakers. If one runs 100 wpc into the center and surround channels and then has 800 wpc on the L&R, really what you have is 100 wpc with 9 dB of headroom on the L&R.
 
Well, I did some testing last night and disconnected my L&R speakers from the system to see how much material was actually being output to the center. What I found was quite surprising. On some of my fav movie tracks like, Tron, The Avengers, X-men on more demanding scenes, the amount of effects coming from my HTM2D was extensive. In addition to the main duties of presenting accurate dialogue, the center channel is also required to be able to reproduce a lot of dynamic effects. I emphasize on the dynamics because what I heard

So this finding has really answered my own question in that the center channel amp, as most of you alluded to, can justify the same level of performance as the main channels. I'm strongly leaning towards adding another MC601 at this point.

Any more suggestions on the two options is most welcome.

Thanks all.
 
c_dk said:
Any theater/presentation system needs to be designed from the center out if you have any expectation of getting paid. Passing the AllCons test was always a part of the contract. Without a prperly designed full range center "stack" you had no chance of getting it right.

Surround sound is like the sizzle of a steak presented in a good steakhouse.....yea the sizzle makes for a great presentation, maybe even fun, but if the steak is tough, it can't fix that.

Amateur home theater, without at the very least, 3 identical full range speakers across the front will always be a compromise.....

The B&W literature I remember always had 3 801s across the front......

Remember in pro theaters, where movies are designed to sound right, use dozens if not hundreds of surround effect speakers.
Click to expand...


What is the AllCons test?
 
scanido,
It's all about the LCR channels and the center is actually the most important, so I'd go for option #2 and even consider a lesser amp for the height channels if budget becomes an issue. I can say having three 601's for LCR is an excellent option. Besides, it looks good in the stack. :)
DSC_2699_edited-2_zpsa4d30ddc.jpg

Tom
 
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I run equal power to my fronts and center, and 60% as much for the surround and back speakers. Seems to work just fine. 60% isn't some sort of magic number, it just is because that's how the amp's ratings aligned in the series.

In my system the surround and back speakers are about half the distance to me as the fronts and center and are of same/similar sensitivity. So, less power for them is quite OK.
 
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@W9TR.... What is goin on with your 151 there? Just curious as I have had mine for almost a year and not sure what you did there... maybe I missed a page in the manual??

Doug
 
If you want to hit reference levels for movies, you want to look at amplifier power as a single piece of the puzzle. Combined with sensitivity ratings, you can see what you need.

The HTM2D2 is rated for 90dB sensitivity. You need 300w of power at a distance of 10ft to get to 105dB peaks which is equivalent to "reference level." So, you'd need to double the power to get reasonable headroom--600w. Unfortunately, the speaker is not rated for anywhere near that power and you'd likely be risking damage with regular usage.

Music and movies are two different beasts. Option 1 makes a whole lot more sense to me; you're simply risking damage to your very nice center channel if you power it with a 600w monoblock.
 
Doug,
I have an MX 135 that wishes it were an MX 151. But it's not. :)
I just named the Blu-Ray player BLUE so it would be easy for the family to figure out.

nalthien,
wow, that's a lot more power than I've ever seen calculated for 105 dB SPL from a 90 dB speaker at 10 ft. Curious about the set of assumptions you're using wrt room size, alpha, etc.

Tom
 
I think a lot of folks, myself included, have far more powerful amps than we'll ever need to achieve our goals. In my case, I think I've got at least 10dB of headroom at my loudest listening levels.

Back when I listened loud (in my 20s), we measured 126 dB in my living room on Alan Parsons' The Gold Bug. This was at a distance of about 15 feet from the loudspeakers. My buddy Mike looked at me and said . . . and he's a man of very few words in such a setting . . . "Man, that's loud as hell!" He was correct. To date, I've never heard a system in a movie theater, night club, or any domestic setting that was any louder. I have attended a few rock concerts that bested that.

We survived as did our ears. To us, it was crystal clear. Unfortunately, the crossover network in one of the Altecs did not survive. It was toast the next morning.

When we watch a movie on Bluray today as a family, I'm blown away by the dynamic range that's available. In my living room, one can achieve call the police levels with a bit of ease. In my 20s, I'd of been turning that **** UP. Now, I'm racing to turn it down.

My how things change.
 
whoaru99 said:
I come up with ~150W to hit 105dB peak @ 90dB/W/m @ 10ft distance.
Click to expand...

You probably used an SPL calculator that assumes 2 speakers which will give a 3-6dB gain depending on the placement of the speakers. Since we're talking about a center channel here, it's a single speaker.
 
No, the center is typically a single speaker so that's what I used. My guess is your calculation didn't include any reflected sound reinforcement.

I've found the results of this calculator and actual measurements in my room align pretty well.

http://myhometheater.homestead.com/splcalculator.html

I used the "near a wall" placement option, which adds 3dB for reflected sound.
 
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whoaru99 said:
I used the "near a wall" placement option.
Click to expand...

That explains the difference, then! I'm using the same calculator.

Depending on room configuration, I think it's probably unlikely that the placement is "near a wall." I could be wrong, but for a single, directional speaker, the wall "behind" the speaker doesn't really count in my book since the frequencies that are going to hit the center channel are going to be directional as well. I doubt that one would see 3dB of room gain for vocal frequencies from a rear wall.
 
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