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,
Welcome to the group.
Maggies do require a lot of power to really sound their best.
I also own a pair of the 3.7's, they are very nice.
I would recommend you pick up a used BRYSTON 4B amp. There are a variety of 4B amps out there that start at 200 WPC and some more then 200 WPC. If you purchase a used one, it would be in your price range and will sound very good.
4B = 200 WPC
4B NRB = 250 WPC
4B SST = 300 WPC
Feel free to PM me if I can try to answer any other questions.
Best Regard,
Magnepan and Audio Research have been 'soul mates' for years. Since you already have ARC equipment, just find a less expensive used ARC amp. There are lots to choose from which meet your criteria and are in your budget. Also, remember that the actual performance difference between a 100w amp and a 200w amp is just 3db in volume.
Thanks very much, your responses are very helpful – you just increased my knowledge on this subject by 100%. I really am starting from zero.

Brauser, I like your suggestion that since I already have an ARC LS117SC preamplifier, an ARC amplifier would be a good companion.

I am really confused about all the amps ARC has made over the years. For cost reasons, I would prefer to get something used. 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.

My local audio dealer suggested a ARC DS 225. I was advised that this is a class D amp, and that another type of amplifier would be a better fit for my system. Again, I don't know the difference between class D and other types of amplifiers.

Do you have any thoughts/suggestions about what models of ARC amps that meet the criteria above I should look for? Any hints about what a reasonable price to pay would also be much appreciated.

Thanks again for the help. I love music, but of all the things I really care about audio components are the thing I know the least about.

Many thanks, Mike
Mallen,

I used an ARC VS-115 with my 3.6R's that matched beautifully. I also swapped in and out periodically with a pair of Rogue Magnum 180 monoblocks that also sounded wonderful. My pre was a Blue Circle.

You couldn't go wrong with the Bryston, but I don't know whether you need that much power at all times. The Maggies project exceptionally well even with 115W.
Brauser,how does the 3 db for 100 watt's compaire to say ah, 700 wpc?, what is the increase number in db here?, then kick that to 6ohm's, mmm, which would in this case be 900 wpc, now what is the db difference between 100 wpc and 900 wpc?
You have to double the amount of power for every 3db increase in volume. 3db is a common click on the volume knob for many preamps. This means to get another 'click' worth of volume you have to go from say ...10 watts to 20 watts, 20 watts to 40 watts and so on. This also holds true at really high power levels such as moving from 500 watts to a 1,000 watts. As you can see, the law of 'diminishing returns' is at work. It may be impressive to see that 300lb,
1,000 watt amp in a system, but it is likely to not make any difference at all versus a 50 watt amp if the speakers are at all efficient. Some of the best systems I have ever heard have had amps less than 10 watts.

With regard to the choice of ARC amps, I have personally used both tube and solid state ARC amps in the past with very good results. I have never heard a bad ARC amp, although it is possible, I suppose, if the tubes are shot or the equipment piece has had some rough treatment. I buy primarily used equipment, but am picky about the visual condition of the item. Typically if it looks mint, there's a good chance that will sound good as well. One really nice thing about ARC is that they try to keep a stock of replacement parts for every product they have ever brought to market. Lots of people send their gear back to ARC for repairs or upgrades. Vintage ARC gear can sound pretty amazing in the right environments. An example is a system I had 20+ years ago using ARC M100 tube mono(s) for the treble panels of Infinty RS1B(s) and ARC D200(s) solid state for the bass towers. Lots of good memories.

Hope this helps.
Buy the Conrad Johnson MF 2500a as you will not do better for the money. $1200 to $1500. Great amp and match for your speakers.
Why don't you get smaller, less expensive Maggie and match it with a proper amp. It will sound better than the larger Maggie with a compromise amp.
All Maggie's like power, does not matter if we are talking about the 1.7 or 3.7
I have owned both. The more power, to an extent, the better they sing. I had tried a class D mono block amp but got much better sound with my SS amp. The correct tube amp would also be good as Simao mentioned.
ARC amps will sound different from Bryston, Conrad Johnson, VTL, Rogue etc. They are all GOOD, it just depends which sound you prefere?
That's where it get tricky, because you probably can't demo them.
Have had Wyred class d amps on my 3.6s. Great amps with lots of power and extremely tight lower end.
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.
Check out ODYSSEY AUDIO. You can get the Stratos Mono amps for $2700 . They received an outstanding review in the December issue of TAS. As a matter of fact the reviewer uses maggies. At that price why buy used?
An agoner I know drives his 3.7s with a pair of Rogue Audio monoblocks. Sounds really good.
I drive my 3a's with Rogue 120's and feel they do a great job and give me a bit more flesh and timbre than any SS I've used. The next best amp I've used with them was a Classe'. If you can find a Classe 201 I think you will be very happy. Rogue M180's would also be a good match if you wanted to go tubing.
I ran my 1.6s for years with a BAT VK-200 at 100 wpc and never felt it was a compromise. I did add a Vandersteen 2Wq sub which essentially made the VK-200 "more powerful" in that the crossover rolled off the signal to the amp starting at 80 hz. In essence the 100 watts were not being heavily consumed below 80 hz.

This was a nice building block approach from a budget point of view. I think VK-200s can be had around $1000-$1200 when you can find them. It is a fully balanced design and you should know they run fairly hot.

Last point--I sent mine off to BAT after 14 years of use and had it re-capped and checked over. Cost was about $400 to get it basically back to new. BAT's service is extraordinary.
Thanks to everyone for all your very helpful advice and suggestions – much appreciated!

Based on the feedback, I think I'm hearing that a solid-state, class A/B amp with 200 W of power would probably work well.

Is there a way to know which of the ARC amplifiers are solid-state? I'm admitted to being very confused about what their naming convention means.

Another naïve question about mono blocks; if I assume I need 200 watts per channel of solid-state power in a single stereo amplifier, is that the same thing as two, 100 Watt mono block amp's?

Thanks in advance for your consideration and help!
Mike
Mike - when referring to a stereo power amp's rating, it is specified "per channel", so the rating of a mono amp would need to be the same to provide the same amount of power. In other words a 200 wpc stereo amp provides the same amount of power as a pair of 200 watt mono amps.
Since you have settle on SS then you absolutely must consider Classe 201 or 200. It will be a great match with your Maggie's. It will leave you not wanting for more or second guessing, really!

Thank me later!
I would not recommend the Modwright recommended above. I had problems with mine and it seemed to run out of power earlier than other amps I have used. If you are willing to look outside the name brands I would recommend the Primare A32 which can be had for $2500 or less and is a powerful 250 watts into 8 ohms. Well built too. The Sanders is another good suggestion. Your system will be great. Happy listening.
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.
If you have settled on Solid State. I would suggest a used Mark Levinson 23.5 amp. You can't beat this amp. It is excellent. also, Classe has amps that are wonderful.

Since you are talking used, here is my solid state used list for the prices you mentioned.

1. Mark Levinson 23.5
2. Mark Levinson 23
3. Krell KSA 250
4. Threshold amps
5. Classe amps

Seriously, you can't go wrong with any of these. As long as they are in excellent condition, you are good to go.

enjoy
I was trying to figure out what  magnepan speakers to get for my new house. Its a 19x21great room with 12 foot ceilings . I was looking at the 1.7 or 3.7 using rogues atlas amp and rp1 preamp,its rated at a hundred watts . I would like the 3.7 maggies but not sure if the Atlas could drive them correctly might need to move up to the m-180 mono blocks? This gets expensive fast.
Hi Partel,

I sent you a PM with some suggestions. Let me know if we can be of further assistance.

Kind regards,

-David
partel - While the Rogue Atlas would technically be able to drive the Maggies and sound fine at reasonable levels, they really come to life when driven by amps with significantly more power than that. The M-180 amps would be much better suited to the task, or better yet their Apollo Dark amps! ;~)
I guess you decided on tube amps again.  Not sure the best for Magggies but you need a lot of juice.  Did you consider the Sanders  amps made for just these kind of speakers. Price may be prohibitive, perhaps buy used?? If still made.?
 Aside from Rogue not sure who else makes an affordable big tube power amp.  Also some are hybrid class D make sure you like it.
I have used the Bryston 4B SST2 with the Magnepan 3.7i's, driven by the balanced outputs of the LS17SE, and the combination was extremely good in my estimation.  The Parasound Halo A21 also works very well with the 3.7i's.  Either the Bryston or the Parasound have enough power to drive either the 3.7's or 1.7's well.

LarryRS
I have a pair of Odyssey Stratos mono amplifiers and have had the 3.7s. in my system for about 6 months.   If your happy with an old Rotel on your vandersteins then you will be knocked out by the Odyssey/ Maggie combo.   Easy to bias ampliers that are hard to beat on a price per watt basis.     I also have a pair of 1980s Spectron (high end tubeamplifiers )that to me are a prefect match, so I see where some suggest tubes, but really you need top notch tube amps to really make the maggies sing.  You can't go wrong with Bryston maggie combo. The parasound would probably be a good value priced way  run them.    I am not a fan of most AR gear and would probably think about selling your pre amp,  then going with a SS amp with a real nice tube pre, but thats just my 2 cents.  On the subject of Class D, its great tech for car sub woofers.
I had an early version of the Odyssey Kismet monos, and the Sanders Magtech crushed them on my 3.7i's. The Magtech can be had for below $3000 now.