I need quick help- Bi-amp Threshold/McIntosh

I was giving strong thought to bi-amping a set of B&W 802 Matrix Series III speakers presently running on a Threshold S350E single amp. I was going to go with a tube top amp bi-amped, and a guy I know is selling a McIntosh MC2700 amp (200 w/pc)which he thought was tube, and offered it to me for a reasonable price. However, in checking this amp out, I found it was SS. I still want to bi-amp this system, but I can get Thresholds for less used if I want to stay SS, and possibly verticle bi-amp if I can find an S350. Or is the MC2700 a great amp which would sound tube like? or even a great bottom bi-amp as my Threshold is silky smooth anyway? ASAP help would be great.... Thanks, Tom. I know nothing about McInstosh. I though they were all tube too.
Trich, in view of the very high probability that the MC2700 has a different input sensitivity than the Threshold amp, you will probably be creating a level-matching problem if you go that route. You would likely have to address this issue with any tube amp you would use on the top as well. It could be dealt with by inserting a passive preamp in line with the amp with the higher input sensitivity and then turning down the volume slightly to match the level of the less sensitive amp. Of course if you used another amp with the same input sensitivity as the Threshold there should be no need for the level matching.

My guess is that if your Threshold is "silk-smooth," you would derive little or no benefit from adding a solid-state McIntosh unit.
Altough I am not familiar with the 2700, all McIntosh amps that I know of have gain contols, so matching gain should be easy.
Also your statement that bi-amping will be of little or no benefit, is wrong. There are are many reasons why it will be of benefit. Two big ones are:
1. Twice the power (you can never have too much)
2. Either more separation between frequencies (each amp only having to handle limited bandwith with horizontal biamping) or more separation between channels (with vertical biamping)

I personally would probably use two Threshold amps rather than mixing with the McIntosh....but I am not a fan of McIntosh.
Sorry about that guys, it's an MC7200 SS amp. Thanks! Tom
I agree with sticking to Threshold.I don,t think its neccesary with the 802s.I tried it with the 801 matrix and preffered the single Threshold. ( s/300 series 2)
The McIntosh MC7200 does have an adjustable gain setting, which when I thought it was tube with that much power, would have been great for a top bi-amp. BUT, when the guy told me it weighed 53 pounds (him thinking heavy, and me thinking light), I started to wonder how what I thought would be a pretty massive amp could weigh so little? My research led me to find it's SS, and 53 lbs still seems light to me for a 200w amp. So I guess the new question would be; would it be worth buying it as a bass amp for the 802 Matrix series III? It would cost me more than the s/300 II I have been offered, as I seem to be unable to find another s/350E anywhere. Both the Thresholds are fairly similar in output, and since the FET 10E has only one balanced out, I could just use the s/300 II from one of the unbalanced pre outs (they are both active) for the bass biamp. Actually, I think I'm answering my own question here. It does seem to make more sence to stick with Threshold, even though the price on the 7200 was very fair. Any thoughts from any of you? Thanks, Tom
First of all, Richard is completely wrong in his statement that bi-amping would give you twice the power. It would only possibly do that if one amp was twice as powerful as the other one -- and only in the frequency band in which it was used. In a bi-amp configuration, the outputs of the two amps do not add together in a linear fashion. And in the case of the McIntosh 7200 vs the Threshold, if the McIntosh amp turned out to be the less sensitive of the two amps (this may not be the case, but it could be) then you would still need a passive volume control to turn down the output of the Threshold to match the 7200.

Trich, I think you have to look at what you're trying to accomplish here. Vertical bi-amping with an identical or similar amp could help a bit, but I don't think the improvements would be that large unless you went to an external active crossover and bypassed the speaker's internal passive crossover. You are likely to get about as much benefit from bi-wiring (if you're using the internal passive crossovers) as you would from biamping -- without the extra clutter and expense for the second amp.

Also, simply buying a single, higher-quality, more powerful amplifier (and bi-wiring) could work very well. Then you could sell the Threshold and hopefully not be out too much dough. Good luck to you. :)

As I said, you really have to examine what your goals are. It may take some experimenting for you to hit that right mix of elements. But that's the fun of this hobby, right?
Plato, thanks but would buying a larger wattage dual out (2 right, 2 left) do anything? I have often wondered why the more powerful T-400 and T-800 Threshold amps had 2 right and left channel outs. If you have two outputs from the same source, how could that benifit a bi-amp speaker? It would seem to me that you are just adding the great expense of a second set of speaker cables, granted with the added benifit of double the cable, but would it really be any different than running double cables off single outs in to a bi-wire speaker? Please fill me in, spare no details, I really want to understand the difference. Thanks much, Tom
Tom -- now you're confusing me... Perhaps you've misinterpreted something I said in my last post. If you're buying a more powerful stereo amp with two sets of outputs for each channel, the main benefit is the extra power. The additional outputs I believe, are just a convenience feature which makes it easier to biwire. I think what you want (correct me on this) is more slam combined with a more liquid and musical presentation. Those two things can be mutually exclusive but do not have to be. Possibly a high-powered hybrid amp (tube driver stage and MOSFET outputs) would give you what you seek. With the B&Ws, biwiring seems to work very well, so I recommend going that route. And I mean two separate sets of speaker cables to each amplifier channel -- definitely remove the straps between the woofers and the midrange section. I have a set of B&W CDM 9NTs and noticed a nice performance gain.

I don't know the power rating of your Threshold amp, but if it is 200 WPC or more then you might not need more power. I am using an InnerSound ESL amp to drive my B&Ws (300 WPC) and that plays them as loud as I stand. I am also using a Z-man ASE tube line buffer, which I picked up used for $120 and that gives me the sweetness and liquidity of tubes with the heft and slam of solid-state. The Z-man unit is excellent and the Musical Fidelity X10-D (for around the same price used) is supposed to be very good as well (but I haven't tried it). The Z-man is a small unit that uses one 12AX7 tube. So if you have enough power in the Threshold, try biwiring and get ahold of a Z-man or an X10-D. I think you'll be pleasantly surprised at how much the B&Ws perk up. Or you could spend a small fortune on a better amp and get no better results. :)
Plato, I think you are confusing bi-amping with bi-wiring:

I went from one 300watt/channel Krell amp to two 300 watt/channel Krell amps. Therefore, I went from 300 to 600 watts per channel. (or in my case with 4 ohm speakers, from 600 to 1200 watts per channel.)
In my case the result was the biggest improvement that I have ever made to my system, but to be fair, I also went form a passive to an active crossover. ... And it was worth every penny.

Now I'm confused. Running 300 watts to your tweeters and another 300 watts to your woofers does not make it 600 watts does it? I'm no engineer, but even my basic knowlege suggests this is still 300 watts? Tom
I think to easily understand the concept, consider the following:

Person Q uses one three hundered watt amp to run his two way speaker system. His speakers have a woofer and a mid-high speaker. The speakers have an internal crossover that devides the power to each amp. For simplicity, lets say each speaker uses the same power. So the 300 watt amp will have 150 watts available for each of them (woofer and mid-highs)

Now lets say person R uses the three hundred watt amp for his woofer and then went out and bought another 300 watt amp for the mid-highs. Person R now has available 300 watts for each of the speakers (woofer and mid-high).