100W+ solid-state amps known for beautiful mids

Audionet

You want to found Quad's house soundstage from another brand of amplifier.

That kind of search is very difficult, and in my opinion ,might not the right way.

You just upgrade from Quad's brand and you will get what you have.

 

One mustn't forget the Fisher SA-300 for one of the best vintage power amps of all time. Talk about smooth meds, wonderful smooth high end, that amp kills it. Everything about the 1959-61 amp was great. It sounds better than the McIntosh MC 240, just does look nearly as (cool) sweet as the MC 240 but sound wise it is a keeper.

I'm reading these posts and kind of envying how (relatively) easy it is/was to find a pretty damn good hundred watt amp.
I find it's a lot harder to find magic when you're looking for 250 w and more.

The best part though? The Quad 405-2 cost me $400. I've generally had in my mind that price correlated with quality (though not ironclad), but this recent pick up is seriously challenging my beliefs.

High end audio isn't about price, its about intention. Since that amp is ticking the boxes for you, if I were you I'd be looking into (if its older than 25 years) making sure that the filter capacitors in the power supply are good so that the amp remains reliable.

perfection, where did that go ?

but hey, you are happy

all that matters !

Thank you all again for your excellent suggestions. I'll keep them all in mind.

Here's what I've done in the meantime: I've picked up a vintage Quad 405-2 to use in the interim. And it is fantastic. It's got the sweetness in the mids, much like my old Quad 909 did.

The Pass X250.5 surpasses the Quad in quite a few areas; namely it has more of a wraparound enveloping stage, more authoritative bass, better separation and layering, larger image size. In general, just a bigger and bolder sound.

But the Quad definitely trades blows! It's more tonally neutral and doesn't homogenize the sound as much as the Pass. I've found that the nuances of the original recording are better preserved with the Quad. The Pass had a tendency to transform all recordings into a larger-than-life version, which is awesome at times but perhaps unfaithful. The Quad also has a more refined smooth treble than the Pass in my opinion. Most importantly, the Quad has a better sense of immediacy or urgency, whereas the Pass could almost sound too relaxed at times. 

The best part though? The Quad 405-2 cost me $400. I've generally had in my mind that price correlated with quality (though not ironclad), but this recent pick up is seriously challenging my beliefs.

This pick-up will allow me to sell the Pass with no regrets, and further to that, I feel no urgency to pick up another amp. I'll really take my time to consider my options and wait for the right opportunity to find a replacement amp in the upper echelons.

@hedonism  What you are looking for is an amp with the right distortion signature. The warmth of the Pass is caused by a 2nd harmonic for example- similar to a lot of tube amps. If you talk to Nelson you'll find he's very aware of how the distortion signature affects the sound of an amp.

If you want solid state you're up against a real problem. Here's the engineering difficulty:
When you apply feedback to an amplifier circuit it will make distortion of its own while suppressing distortion in the amp. The added distortion is audible as harshness as brightness since its all higher ordered harmonics which the ear interprets in that way since it converts all forms of distortion into a tonality of some sort.


Now tube amps actually have more higher ordered harmonic distortion, but it is masked because tube amps also make a significant 2nd and 3rd harmonic which masks the presence of the higher orders. Getting a solid state amp to do this is a bit of a trick with traditional amplifier design.

However it turns out that class D offers a means around this- it turns out that if you used the right encoding scheme, that and the dead time used in the class D amp tend to result in lower ordered harmonics. A lot depends on the design! But if its done right, the result will be an amp with a distortion signature that masks the higher ordered harmonics, allowing for a very smooth midrange and highs with overall lower distortion than you can get out of a tube amp. IMO IME you're better off looking for such an amp- one example is the AGD Audion, which does make over 100 watts into 8 ohms so it should be enough power.

I suppose one could consider the speakers and cable as a part of a "sub-system" that would include the amp. Depending on that system, the excellent mid range performance you are seeking might take some experimentation. McCormack/SMc can help guide you. I would suggest the DNA series which can be tailored and upgraded as your needs change. McCormack have refined a fundamentally and technically sound design over a long period of time. I have not heard every SS amp, but I do not recall
any over the past 30 years that sounded "better."
You could go with a tube amp, but that can be costly over a period of time with necessary tube replacement. Good luck, happy listening!

New Classe Delta, 12W in class A for stereo amp (30W for monoblocks I believe) sweetness, more dynamic, details and bass solidity than the tube-based ARC Reference setup it replaces without sacrificing on mid-range. There's a very thin line between the best tube offerings and the best SS ones at this price point. 

@gryphongryph I am using VTA SP14 which is the predecessor that Don Sach's is based on. My speakers are ATC SCM19. The founder of ATC, Billy Woodman recommends 100W+ with high damping factor on his speakers, so I'd like to adhere to his recommendations. For the reason, I think it's headroom, since transients require a lot of current.

@ghdprentice I believe that my speakers are incompatible with the vast majority of tube amps. I'm taking advice on amplifiers based on the ATC founder Billy Woodman, in that ATC speakers are best with 100w+ class a or ab solid state amplifiers with high damping factor. I think the problem is that most tube amps have extremely low damping factor, which apparently doesn't mate well with ATC speakers, though I have yet to try myself. So for now, I'd like to stick with a solid state power amp with a tube pre-amplifier to get at least some of the tube magic in! If that doesn't pan out, maybe I'll try one of those monster 100W+ tube amplifiers like the Rogue 100, and if that doesn't work, then I might move on from ATC and try something more tube friendly like ProAc bookshelves.

Having owned and auditioned lots of amazing SS amps over the last 50 years, while some are very good. If you want great midrange just get a tube amp. I stayed away for decades until finally Audio Researched produced the auto biasing and microprocessor controlled tube amp that had good tube life… Reference 160S. My question to myself has been, why didn’t I do this decades ago! My system is now all tubes, and it is more involving and satisfying than I ever imagined possible.

@peguinpower. I had the exact opposite experience with the Pass X150.8 and Audio Research.  I found the ARC to have wonderful mids and the Pass very sterile lacking any midrange magic.  Could be system dependent but it's crazy how we have totally different experiences.  

I searched long and hard to find an amplifier that sounded good with my Martin Logan CLS IIz. After trying numerous high-end tube and solid-state amplifiers I settled on the Classe CA-200.

If you can get a 200W+ amp, get it.
the headroom you will need.

Buying based on watts is not a good formula. 

Like someone else mentioned, I have Keith Herron's M1 monoblocks.  They are "only" 150 watts each, but they have a very large toroidal transformer that provides all the headroom I need.  Previously I had Rogue Audio M180 tubed monoblocks (which I loved), but the M1's provide all the power I need and are cleaner and more detailed than the M180s.

If my budget allowed, I'd be more than happy with a 100 WPC darTZeel amp.  Some of the best midrange I've heard came from a 48 WPC Line Magnetic 805iA integrated powering Harbeth 40.1 speakers.  Having plenty of power certainly can help in the right design, but there's so much more to an amp than how many watts it puts out.

Bakoon amplfiers have the most pure,detailed and natural sounding midrange I have heard.They sound neither warm nor cold and when you hear them aspects like that become irrelevant because they just sound right.They used to make 100 watt monoblocks but I am not sure that they do any more and they are not about power anyway.They are about clarity and finesse.They sound a bit like the Dartzeel but with even more immediacy, clarity and vibrancy although perhaps not quite as good bass.They also require more careful speaker matching and are much better driving 8 ohms than 4.

If you can get a 200W+ amp, get it.
the headroom you will need.

Herron M1 is a bit over $5,000, but the mids are excellent.  In fact, the entire spectrum is outstanding, timing and dynamics are in a class of their own.  IMO, one of the best amps available at any price every manufactured.

Sorry I missed the 100w plus part of this. 

McIntosh MC30’s or MC240

”hedonism” The Pass point-8 series is definitely more neutral than the .5
Great amps!

+1 for SMc DNA modified by Steve and Patrick

Can I ask what pre amp you are using ?
I have been using a Supratek Cabernet pre with a Belles SA30 class A power amp rated at 50w
my speakers are 87db in sensitivity, but don’t go below 85db so easy to drive for my amp, and it can play much louder than I care to listen too.
The mid’s are exceptional and the high’s are beautiful, the bass for me is good, but I would guess that your amp would be better in that department. Do you need 100w + in power,? A lot of good class A amps are at 30w and for 3db louder you need 10 times the power I think!
Good luck in you search.

PureAudio from NZ are beautiful and single ended, get a lot of rave reviews.
http://totallywired.co.nz/pure_audio_power.html

@fstein 

What is wrong with the Pass you now have?

It's an excellent amplifier and I've really enjoyed my time with it so far, but it's not flawless.

1. It's a very high performer, it's got a very spacious soundstage, wide deep and tall, with excellent layering and separation. It has large vivid and palpable imaging. The bass is huge and lots of fun. But at the end of the day, it's slightly too coloured for me, and despite the warmth, the mids still lack some of that sweetness and purity that the Quad had. There's still some dryness to the PASS X250.5's mids.

2. It has quite low input impedance at 12k ohms. That means there's some bass roll off with the tube preamp that I have currently. I could ameliorate that with a higher uF value output capacitor, but I would like to avoid soldering and I'm worried what a higher value cap would do to the sound. Buying a new amp is just easier, one with higher input impedance this time.

3. It takes quite a while for it to warm up and reach peak performance. I don't like waiting around that long, especially when I've had a long day at work and just want to kick back and listen to some music. I'd also rather not leave it on 24/7 because it's an older unit and I don't want the capacitors to dry out (plus the energy bills add up over time!)

@millercarbon. 

    Yup.
acoustic, electric, the acoustic, is stellar.
electric, Dave mustaine, and most metal is crunchy, evil, and almost flawless!

  +1

What is wrong with the Pass you now have?

Hypex Ncore 400 monoblocks are hard to surpass. Just add a shielding wall between the amplifier and the power supply to get the best results. Keeping the operating temperature as low as possible is worth the effort and results in optimum performance.

Contact Steve,or Pat at SMc Audio and they will make you happy. I own a modded DNA amplifier from them and cannot speak highly enough of it’s performance as well as the down to earth, honest and professional customer service I have, and continue to receive. Rare commodity these days. I also enjoy a heavily “massaged “ TLC preamplifier from them. They will work with you and your system until it is correct…. For you and your situation. 

Luxman 590AXII which is class A up to the first 30 watts definitely fits the bill. I found it to be fairly neutral with just a hint of warmth.

However, after going through a number of class A SS amps, I’ve reached the conclusion that, at least for my tastes and my ears, if you want beautiful mids there’s still nothing that beats high quality tube amplification. I feel that a few modern interpretations of tube amps are closing the gap between SS dynamics and tubes without losing the all-important midrange magic.

Pass XA 100.8. Mine is super 

Pass XA, Pass Aleph, Conrad Johnson Premier 350SE or MF2550

+1 for the Brown Electronic Labs model 1001.  Get a pair and run them as mono blocks!
Cheers

You might like the Circle Labs A200. Here's a recent review in Positive Feedback: https://positive-feedback.com/reviews/hardware-reviews/circle-labs-a200-integrated-amplifier-thank-y...

If you prefer separates, the M200 is the equivalent power amplifier.

Heads up that I import Circle Labs products into North America.

Any of the older Mark Levinson 3 series 331, 332, 335, 336. When recapped they are amazing for mids and highs. Not bad for bass, but there are better for that. 

Check Pilium - whatever you pick from the Divine line. 

Ayre strength of the topology is balanced, i would look elsewhere for single ended.

As for SMC, you got bad advice as Steve ( yes i am a fan ) advise to call him w serial and model BEFORE buying used.

Jim

@hedonism, the obvious answer to your question is, it depends, to some extent, on core component matching and, ultimately, on the business end of any sound system... the speakers. If 100 watts (or thereabouts) and $5.000 (give or take a little) are the strict parameters, you might want listen to what Simaudio Moon has to offer or seriously discounted or used McIntosh gear. I'm sure the other recommendations are good, too, but I try to refrain from recommending stuff I haven't heard myself and liked.

The lingo with which one uses to describe a piece of their system amuses me. Certainly in different systems with different room treatments will always generate a different sound, you either like it or you don’t. Kind of like a waste of time…Warm, soft, in, out, up, down, light, dark ? I use vintage Yamaha pc5002m / pc4002m together, to date I’ve had nothing better.

StarKrimson Ultra Audio Stereo Amplifier

Does anyone have experience using Ayre single-ended? I realize that best results are achieved using a fully balanced set-up when it comes to Ayre gear, but my tube preamp is single ended, and it’s going nowhere. I think my Rockna DAC is internally single-ended as well.

@sumaato thanks for the tip on the quad 405-2, I will buy one to keep as a back-up amp, and possibly even my main amp if it's much better than my old Quad 909!

@avanti1960 Nope! While this post is to help me decide which direction I want to move for my next amp, it's always great to learn more about the all-time great amps of yesterday. Buying used is also always an option.

@mikelavigne I deliberately didn't include a price range, because I just want to learn more, not necessarily decide which amp next right away,

Yes they are. I recommend Pass XA series.

Luxman
Ayre

A lot of people are going to suggest Pass and I suggest you listen to them as well.  It's not my cup of tea at all but when you comapre it to Luxman and/or Ayre you should have a clear preference come out that works for you.

Jeff Rowland Model 2
Ayre 5-vxe

Well, I'm sitting here listening to my vintage Quad.......405-2. Having owned the Quad 909 before, I much prefer the 405-2. It has the midrange, but it also has dynamic power and smooth upper frequencies, far from rolled off. The bass is nowhere near as deep as my class D amp but it has an unforced, realistic quality. It's a finer quality. As for the soundstage, there is a cohesion  of presentation that doesn't have the piano left and right hands separate, nor is the voice forward of the band, but it can still create those startling stereo experiences of sound coming from outside the room. 

Quad 909 back in the day had a reputation for the best mids running up to $5000. I've used it in the past and I would definitely say that the mids were the highlight on that amp. It wasn't overly coloured, a hint of warmth, but it had a purity and sweetness to its mids. Unfortunately, mostly everything else was okay at best, kind of rolled off at both ends and congested stage-wise.

LSA Voyager GaN 350

See the AG threads for owners opinions

should the list include amps currently in production?

@blackbag20 A difference of philosophies, I reckon. I'm of the opinion that everything is coloured. "Wire with gain" doesn't exist in my books. To me, it's all about mixing and matching components to offset weaknesses and create synergistic sound. 

+1 for darTZeel.

very low noise, no global feedback, minimal parts count in the signal path, swiss built like a tank.

darts don’t sound solid state, and don’t sound like tubes, they sound like music.

3 years ago i brought 2 really spendy tube amps into my system, the Lamm ML3 mono’s and the VAC Statement 450 mono’s and compared them for 4 months, to my darTZeel mono blocks. preferred the timbre and textures, realism and transparency of the dart and those went away.

your OP does not specify price range only mentions $5k related to the Quad amp. you can find used darTZeel 108 stereo amps in the $8k-$14k range. the newer 108 Mk2 version lists for around $40k. the Mk1 versions with the SNCP upgrade are better dynamically....most have been done. and that early version of the 108 has the super pure and harmonically complete mid range, and amazing soaring sweet highs no other solid state can quite touch. and if you value a grainless and liquid musical viewpoint, no solid state is in the league of the darts.