Do I need to amplify all of my channels?


Gurus:

I have recently moved to a new house that has a media room, into which I am trying to harmonize my current equipment. My existing setup consists of a McIntosh MHT-100r, a pair of Bowers and Wilkins 803s, and a Bowers and Wilkins HTM2 center channel (wall mounted and left in the old house were the surrounds - decent klipsch).

My new media room includes high end front in-wall speakers (not audiophile but top of the consumer range that I may move to sides or rear), above average consumer in-wall sides and rear speakers, and a decent wall mount Sonance center channel that I will sell. There is also a solid Velodyne sub that I intend to use (I am writing from an American Airlines inflight wifi connection and cannot remember the model).

I have long believed that my MHT-100 (80w at 8ohms) is underpowered for my B&Ws. My desire is to add an amplifier to my system, but I don't know how many channels I really need. The MHT-100 has 5.1 incorporated amplified channels, but can pass 7.1 (for which my media room is wired) to an amplifier. The MHT does not have balanced outputs.

My primary goal for this room is media, though it is the best equipment in my house - so i will listen to Andreas Vollenweider Caverna Magica on this system.

So the questions are: do I just need 3 channels of amplification for my B&Ws or do I need 7; if I use an amplifier for just three channels, how does the system work (ie volume control) and how do I hook it up; if I use a 7 channel amplifier, will I overdrive my sides and rears (they are rated at 100w, I think); and any other questions I haven't considered.

I'd also appreciate any options that amyone would like to suggest, such as "get the Outlaw 7 channel 200w" or "McIntosh MC-x is the only way to go with the equipment you have." I am trying to do this on a smart budget, as media room furniture is also needed and money isn't endless. However, I want the right equipment so I don't have to buy it twice.

I appreciate any feedback/suggestions/advice/criticisms.

Thanks in advance,
Mark
msetexas
Srwooten

Thanks for the thoughts, yes the MHT100 is a bit of a wimp. When it bought it, the MHT was a great compromise for me - excellent quality, but not separates. I knew that I would eventually add an amp and still have a great processor - that time has come. I am leaning toward 7 channels as my room is wired for such and the MHT produces 7.1 if it is offloaded to an amp.

Is there any particular logic related to amps whose power doubles into 4 ohms? Are there particular Marantz models recommended?

Also, I am not opposed to a used amp, in fact, I may go that way - I know there are several bargains (quality versus price depreciation) in older models.

Thanks
Mark
your room and listneing levels should give you an idea on your power needs.... However, generally speaking, having BW about, think of power, as your friend. your best friend.

Certainly speakers need power. BW speakers do well with a lot of it, I've had 5 sets.

I don't feel it necessary to stay 'same - same' with processor & amp either. With speakers, that approach works indeed, across the front 3, with rears & surrounds, mattering much less.

Assuming here you have a processor - AV multi ch preamp, or receiver on hand and further, it has main pre outputs, DEFINITELY adding an amp is IME a necessity with BW.

As to how many channels? you pick. Flavor? Again, that's on you too. Figure EVERY ch in the amp will drive one speaker and the proc will drive the powered sub. Simple.

I'd look for a smooth top end in whichever amp first. Secondly, 200 wpc or so, or in that area. I'd bet the ATI 2505, or one of the newer 1805, or 2005, ATI amps would be a good match.

Another thought too is your note on using your existing gear/space for 2 ch. audio. Perhaps TWO amps would be a better approach. One for center surrounds and rears and one for the main 803s. This would be my choice at some point if not initially. Naturally, for a more cohesive sound field, the optimum fix is same speakers all around, and the same flavor power all about too. ?? Well, it is a goal, but not always done 100%. Truth be told you can do pretty well with some compromises to that theme too.

Try also to minimize other diffs too if a pair of amps is sought out... like interconnects and power cables & speaker wires.

I went your route somewhat but in reverse. Adding a two ch amp first. Then, felt for myself, a multi ch amp would be best and as above, more congruent given my speaks are closely mated all around. My current 5 ch amp however will only drive 3 ch of my system, L, C, & R, WITH the initial SS amp driving my rears in a 5.1 affair.

Why? Two reasons... it has a better sonic thumbprint than the Odyssey Stratos Plus +, and it allows for more coherence in the important area. A third aspect is that with many multi ch amps, and mine in particular, using less of the ch at one time allows for a higher power output across fewer channels.

What about the other two ch of the 5 ch amp? I really am not sure how I'll use them.

Good luck.
If you want to 'wake up' bass in your speakers I suggest to look to power them up in 500w/ch amplification range.
I've got my itchy hands to upgrade to Wyred4sound SX500 monos from BCarver Sunfire SRA(250W/ch) which I also can recommend to you.
BTW if you're interested in Sunfire SRA(which is much better match then your current amp) drop me a note with possible offer(open).
I though Marantz made a multi channel amp in its' reference series, but I was wrong. Here is a great 3 channel amp that would sing with your B&W's:
Krell 3 channel

"Is there any particular logic related to amps whose power doubles into 4 ohms? Are there particular Marantz models recommended?"

It shows good power reserves when your amp can double its 8 ohm power rating when going to 4 ohms.

msetexas
>

IMO & IME... power amps which have great power supplies with an abundance of power storage capacity, are as good or better than those which double down their power with regard to impedance drops.

For ex. Krell vs. BAT amps.... Krell doubles output with a halved impedance load.. My KAV250 went to 500wpc at 4 ohms.

My previous BAT VK500 W/BAT pack opt.... put out the initial 250 as the Krell, but at 4 ohms less than 500wpc.

Theoretically you possibly could drain or use the total 500 or 440 wpc from each amp... but logically, with 89-90Db speakers like BW 803s, continuous power outputs of those levels simply won't occur with logical use.

Even some incidental peaks of high freq under sane listening conditions should fall short of the top rated output of either amp.

So there's that... simple doubling of power output is not indicative of any amp being considered either good or bad. Theres more to it. I sold off my 9NT + kav 250 due to it's sonic signature. Not due to power issues.

The BAT vk500 sounded worlds apart better.... and should have perhaps if $$$ means anything. The Krell then was about $3K new. The BAT was about $5.9 new.

Other than sound, I feel it was the power supply and design topology of the BAT which made that diff for me. KAV 250 = 45lbs.... BAT vk 500 = 105lbs. Where's the beef? it's in the power supplies or isn't. digital amps aside.

If you like Marantz' sound maybe you should look into McIntosh, odyssey, Butler, or ATI. Of those only ATI doubles down power with halved imp, though. All however sound very good.