Please help a rookie –used amps for magnepan 3.7?


This is my first post on any kind of audio forum, so I apologize in advance for my ignorance if I’m violating any convention/etiquette etc. I love music, but confessed to being overwhelmed regarding all the technical development since the days of tubes.

I am planning to buy some Magnepan 3.7 speakers. I don’t think I can afford to buy the ideal amplifier for my system right now, and would very much appreciate any advice or suggestions about what sort of used amplifier set up would be the best compromise between cost and sound quality for the near term.

I use both digital and analog sources and have Audio Research LS17SE tube pre amp and Bryston DAC and 8 year-old Rotel RB 980 BX amplifiler, which I believe is rated at 125 W. This set up has worked well with my current Vandersteen II ce speakers.

My local audio dealer told me that for the maggies I should get an amp with at least 200 W of power and suggested an Audio Research DS 225, which I could buy used for $3,900. This is a bit more than I would like to spend, however if the consensus of the group is this is the best option I could start saving towards this.

Alternatively, I was wondering if there might be a slightly less expensive amplifier suggestion somewhere closer to $2,500? (I might be able slip that one as my wife with minimal angst).

I’ve always been interested in the idea of separate mono block amplifiers. From my admittedly uninformed perspective, the logic of separate amps, potentially located closer to the speakers seem reasonable, however I have no idea if that’s accurate or even an option I should consider. Maybe I should consider getting another Rotel RB 980 like the one I have now, which I think should be fairly inexpensively – does that make sense?

I very much appreciate any and all advice and suggestions from the knowledgeable members of this community.

Thanks, Mike
mallen1010
Mallen1010,
I don't know much about Audio Research SS amps but wanted to let you know I just came across a (used) 300.2 that listed here today for $2300.00. Looks like 500 wpc into your Maggies.
The class D amps have a sound of their own, which you should hear of course before making any investment. Each manufacturer of amps with Class D power, sound different from one another so again you'll be wise to audition them.
Mallen ... My rig is centered around ARC gear. See my system description. Let me offer a few comments about ARC gear, subject to an important caveat which I will speak to below.

First, you post that "I was advised that my preamp has "balanced" inputs and therefore I should get an amplifier that has "balanced" inputs as well. I'm not really sure what these are, and don't know if that advice is sound." Respectfully, IMO the advice, if accurately reported, is a contradiction.

My Ref 5 SE linestage has both balanced (XLR) and SE (RCA jacks) inputs and outputs. In my case, my CD-8 CDP is tied into the XLR inputs of my Ref 5 SE, while my PH-8 phono pre is tied into the RCA inputs. Why the switch?? Because the PH-8 only has RCA output jacks. :)

However, my Ref 150 amp only has XLR inputs ... no RCA input jacks. So I use the XLR outputs of my Ref 5 SE to drive the Ref 150 amp. FWIW, the ARC website reports that the LS17SE main output is 12dB off the balanced outputs, but only 6dB off the SE outputs.

IOW, what I'm saying is that you are not restricted to going all XLR or all SE. You can mix and match.

Second point ... are XLR connections better, equal to, or worse than RCA connections?? That's a subject that is way beyond the scope of this thread. The opinions run the gamut of "Yes," "No" or "it depends."

IME, my bias (pun intended) is XLR all the way. In fact, if I ever get around to upgrading my phono pre to the ARC Ref Phono 2 SE, I'd use the XLR connectors. Ditto between my TT and the phnoo pre. But's just my opinion.

Third point ... yes, there are benefits of you using an ARC amp with your LS 17 SE. Reason: natural synergy when using ARC products because they are designed to be electrically compatible. Here again, component electrical compatibility (or lack thereof) is a topic that is way beyond the scope of this thread. But suffice to say, you should *NOT* have a problem using a modern ARC amp with your LS 17 SE.

Fourth point ... tubes versus solid state. Too da*m complicated a subject. Suffice to say that if the Maggies have a flat impedance curve, even if low (say 4 ohms across the frequency spectrum), most modern ARC tube amps should be fine driving the load.

Fifth and last point ... my caveat. I have read that Maggies are power hogs ... the more juice the better. I recall reading that one reviewer used a Ref 150 (150 wpc) to drive Maggie 3.7s. The Ref 150 was the subject of the review ... not the Maggies. I believe the reviewer commented that the Ref 150 did an OK job driving the 3.7s to OK sound levels, but kinda barely.

I'll let other A'gon folks who have had their way with Maggies speak to the power requirements of 3.7s, but I'll leave it by saying "yellow light - use caution."

Having said all that, if I was inclined to go with ARC gear, I would opt for a higher power amp than the VS-115 (my prior amp) or the Ref 150. Unfortunately, tube watts ain't cheap. Even a used Ref 210 is way over your stated budget. Solid state may be the way to go.

BTW, many A'gon members say nice things about Bryston gear. If a high power Bryston SS amp is compatible with your LS17 SE, I'd consider it.

Good luck and keep us posted on your progress. I'm sure others will add (or maybe correct) my advice.

Regards and welcome to the Forum,

BIF
Mike, based on your power needs, associated equipment & budget, I would recommend a 2nd hand Modwright KWA-150. The last example that went up for sale on AG was asking $2888. But that was 10 months ago, so if you're patient and look around, you should be able to find one around your budget. The KWA-150 is beautifully built by a talented modder/designer Dan Wright. It is fully dual mono (ie: with separate power transformers, power supplies and input and output stages), true balanced, and as the product name suggest, has 150 watts@ 8ohms and 250 watts@4 ohms which is enough power to properly control your Maggies.

The KWA-150 sounds tube-like and has wonderful inner detail. It is also a fast amp. It was designed to work well with tube preamps (and is usually matched with Dan's LS36.5 or LS100 preamps at shows). Another cool feature is, there is a toggle on the back to switch to 'bridged mono' mode, allowing you to connect a 2nd KWA-150 if you feel you need more power or want to run shorter speaker cables later on.

Your Dealer's recommendation of the Audio Research DS 225 is understandable given the brand synergy, but the DS 225 an unremarkable class D amp, whereas the KWA-150 is a class A/B amp which sounds more like a good class A amp and is switchable between low and high bias. An easy recommendation.
I'd suggest a Parasound Halo A21 before you spend a lot more money. They are in your budget new and can can found for $1600 used. 250wpc @ 8 and 400wpc @4 ohms.