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

Showing 2 responses by melbguy1

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.
Teeshot, not discrediting your experience with your Modwright at all, but in all honesty you would be the first person i've ever heard of having a problem with that amp. I drove my old 87db/4 ohm Marten Coltranes with a KWA-150 & it provided very good control and authority, and the Coltranes like a lot of power. I'm not sure what speakers you were driving, but they must have been amp killers.