b&k or Bryston or McCormack?


Greetings. I am purchasing the new Martin Logan Ascent (replaces the SL3)loudspeakers.My quandry regards amplification. My budget is limited following the speaker purchase but I need amps. The B&K Reference 4420 is on closeout at my local retailer for $800 (225 watts @8 ohms x2). I was originally considering buying either the Bryston 4b-st, of the McCormack 225. However for less than the price of one of those amps, I can buy two B&Ks and bi-amp. My room is 27 ftx 18 ft, speakers are for music primarily, but will see some HT action. My musical tastes are varied but primarily alt/classic rock. I don't really have the luxury of an in-home audition, so I thought I would turn to the web for some wisdom. Thank you all in advance for your thoughts and consideration, I really appreciate your input.
mspencerod2cd0
I've owned the B&K 4420. It was very nice but I bought a pair of Hales Rev 3s that are a difficult load. Mr. Hales (speaker designer) suggested the Aragon 4004 or 8008 for their effortless ability to drive difficult loads. I havn't listened to the Bryston but many people compare the sound of the Bryston with the Aragon. If I didn't have the Hales I would have been very happy with the B&K and saved some cash. Don't let what is currently popular change you decision. The B&K will do the trick unless you have very difficult to drive speakers.
Mspencerod: Sorry, I should have looked at your speakers more carefully. I just checked the Martin Logan web site and your speakers might be a difficult load. (4 ohms, 1.2 ohms at 20kHz) You might want to look for a amp that doubles down (ie. doubles wattage when halfing the load). Ignore the power ratings, especially at 8 ohms. The B&K is rated 225 watt/8 ohm but only 350 at 4 ohms. To double down it would need to go from 225 to 450. You might want to call Martin Logan and see if they can suggest some amplifiers (after all they designed the speaker).
By separating the high frequencies from the low frequencies, you effectively double the power reserve of each amplifier and increase its stability. Since he would have a dedicated amp to deal with the "low current" sections ( panels ) at the reactive high frequency points WITHOUT having to deal with the high current demands of low frequency reproduction, he should be fine. In turn, the current demands needed for low frequency reproduction would not be affected by the tweeters reactance at very high frequencies, letting it concentrate on supplying power where it is needed most. As mentioned, an electronic crossover would further increase the efficiency of the system and allow fine tuning / tailoring to meet the tonal balance of ones' room. Kev's suggesting about contacting Martin Logan is a very valid one though and would surely be worth the time and money. Sean >
The Ascent is no big deal to drive, a 1 ohm dip at high frequencies will not present a problem and is not a difficult load. There are not huge impendance swings with this speaker -- this is the real challenge -- so, without question, any of the amps you mention should be fine. Why am I so sure? I'm driving CLS's with a McCormack DNA1 Deluxe and am quite happy. (Can I do better? "Yes". But this the amp I had on hand. There's more possible with a high current/voltage tube amp and a REL sub-woofer -- my next moves -- but since this amp drives the speakers without effort, images well and makes damn fine holographic music I have no doubt whatsoever that whichever of the amps you mention will do a good job.) Just pick the one that sounds best to you. The person who advised bi-amping (imho one amp for the panels and one for the woofers is the way to go) is right on. This makes a huge difference with the Logan hybrids and gives you a great deal of flexibilty -- pick the best sounding amp for the panels and another for the bottom end. By the way, I hear that the Ascents do a much better job of integrating the woofer and panel than the SL3. Let us know how you make out.
I have owned the DNA1, B&K, and the Bryston 4BST. In my system, the Bryston was the most controlled in the bass and the most transparent in the midrange. The DNA1 was close. The B&K was warmer however. A very fine color, but pleasant. Almost tubey. You should use a tube preamp to get a little warmth also. The amp I would use with that speaker is the Aragon 4004 or the 8008 I think they call it now. The 4004 has worked well with ML speakers and can drive that wicked load. If you can find an ARC D300, that is a good amp with that speaker also. Even better than the Aragon, but more money. Try before you buy.