My Long List of Amplifiers and My Personal Review of Each!

So I have been in a long journey looking to find the best amplifiers for my martin logan montis. As you know, the match between an amplifier and speakers has to be a good "marriage" and needs to be blend exquisitely. Right now, I think I might have found the best sounding amplifier for martin logan. I have gone through approximately 34-36 amplifiers in the past 12 months. Some of these are:

Bryston ST, SST, SST2 series

With all that said, the amplifiers I mentioned above are the ones that in my opinion are worth mentioning. To make a long story short, there is NO 5 CHANNEL POWER AMP that sounds as good as a 3ch and 2ch amplifier combination. i have done both experiments and the truth is that YOU DO lose details and more channel separation,etc when you select a 5 channel power amplifier of any manufacturer.
My recollection of what each amp sounded like is as follows:

ATI SIGNATURE SERIES 6005 (great power and amazing soundstage. Very low noise floor, BUT this amplifiers NEEDS TO BE cranked up in order to fully enjoy it. If you like listening at low volume levels or somewhat moderate, you are wasting your time here. This amp won’t sound any different than many other brands out there at this volume. The bass is great, good highs although they are a bit bright for my taste)

NAD M25 (very smooth, powerful, but somewhat thin sounding as far as bass goes)
Bryston sst2(detailed, good soundstage, good power, but can be a little forward with certain speakers which could make them ear fatiguing at loud volumes)

Krell (fast sounding, nice bass attack, nice highs, but some detail does get lost with certain speakers)

rotel (good amp for the money, but too bright in my opinion)

cary audio (good sound overall, very musical, but it didn’t have enough oomph)

parasound halo (good detail, great bass, but it still holds back some background detail that i can hear in others)

lexicon (very laid back and smooth. huge power, but if you like more detail or crisper highs, this amp will disappoint you)

McIntosh mc205 (probably the worst multichannel amp given its price point. it was too thin sounding, had detail but lacked bass.

butler audio (good amplifier. very warm and smooth sweet sounding. i think for the money, this is a better amp than the parasound a51)

pass labs (very VERY musical with excellent bass control. You can listen to this for hours and hours without getting ear fatigue. however, it DOES NOT do well in home theater applications if all you have is a 2 channel set up for movies. The midrange gets somewhat "muddy" or very weak sounding that you find yourself trying to turn it up.

classe audio (best amplifier for multi channel applications. i simply COULDNT FIND a better multi channel amplifier PERIOD. IT has amazing smoothness, amazing power and good bass control although i would say krell has much better bass control)

Update: The reviews above were done in January 2015. Below is my newest update as of October 2016:

PS AUDIO BHK 300 MONOBLOCKS: Amazing amps. Tons of detail and really amazing midrange. the bass is amazing too, but the one thing i will say is that those of you with speakers efficiency of 87db and below you will not have all the "loudness" that you may want from time to time. These amps go into protection mode when using a speaker such as the Salon, but only at very loud levels. Maybe 97db and above. If you don’t listen to extreme crazy levels, these amps will please you in every way.
Plinius Odeon 7 channel amp: This is THE BEST multichannel amp i have ever owned. Far , but FAR SUPERIOR to any other multichannel amp i have owned. In my opinion it destroyed all of the multichannel amps i mentioned above and below. The Odeon is an amp that is in a different tier group and it is in a league of its own. Amazing bass, treble and it made my center channel sound more articulate than ever before. The voices where never scrambled with the action scenes. It just separated everything very nicely.
Theta Dreadnaught D: Good detailed amp. Looks very elegant, has a pleasant sound, but i found it a tad too bright for my taste. I thought it was also somewhat "thin" sounding lacking body to the music. could be that it is because it is class d?
Krell Duo 300: Good amp. Nice and detailed with enough power to handle most speakers out there. I found that it does have a very nice "3d" sound through my electrostatics. Nothing to fault here on this amp.
Mark Levinson 532H: Great 2 channel amp. Lots of detail, amazing midrange which is what Mark Levinson is known for. It sounds very holographic and will please those of you looking for more detail and a better midrange. As far as bass, it is there, but it is not going to give you the slam of a pass labs 350.5 or JC1s for example. It is great for those that appreciate classical music, instrumental, etc, but not those of you who love tons of deep bass. It is articulate sounding too
Krell 7200: Plenty of detail and enough power for most people. i found that my rear speakers contained more information after installed this amp. One thing that i hated is that you must use xlr cables with this amp or else you lose most of its sound performance when using RCA’s.
Krell 402e: Great amp. Very powerful and will handle any speaker you wish. Power is incredible and with great detail. That said, i didn’t get all the bass that most reviewers mentioned. I thought it was "ok" in regards to bass. It was there, but it didn’t slam me to my listening chair.
Bryston 4B3: Good amp with a complete sound. I think this amp is more laid back than the SST2 version. I think those of you who found the SST2 version of this amp a little too forward with your speakers will definitely benefit from this amp’s warmth. Bryston has gone towards the "warm" side in my opinion with their new SST3 series. As always, they are built like tanks. I wouldn’t call this amp tube-like, but rather closer to what the classe audio delta 2 series sound like which is on the warm side of things.
Parasound JC1s: Good powerful amps. Amazing low end punch (far superior bass than the 402e). This amp is the amp that i consider complete from top to bottom in regards to sound. Nothing is lacking other than perhaps a nicer chassis. Parasound needs to rework their external appearance when they introduce new amps. This amp would sell much more if it had a revised external appearance because the sound is a great bang for the money. It made my 800 Nautilus scream and slam. Again, amazing low end punch.
Simaudio W7: Good detailed amp. This amp reminds me a lot of the Mark Levinson 532h. Great detail and very articulate. I think this amp will go well with bookshelves that are ported in order to compensate for what it lacks when it comes to the bass. That doesn’t mean it has no bass, but when it is no Parasound JC1 either.
Pass labs 350.5: Wow, where do i begin? maybe my first time around with the xa30.8 wasn’t as special as it was with this monster 350.5. It is just SPECTACULAR sounding with my electrostatics. The bass was THE BEST BASS i have ever heard from ANY amp period. The only amp that comes close would be the jC1s. It made me check my settings to make sure the bass was not boosted and kept making my jaw drop each time i heard it. It totally destroyed the krell 402e in every regard. The krell sounded too "flat" when compared to this amp. This amp had amazing mirange with great detail up top. In my opinion, this amp is the best bang for the money. i loved this amp so much that i ended up buying the amp that follows below.
Pass labs 250.8: What can i say here. This is THE BEST STEREO AMP i have ever heard. This amp destroys all the amps i have listed above today to include the pass labs 350.5. It is a refined 350.5 amp. It has more 3d sound which is something the 350.5 lacked. It has a level of detail that i really have never experienced before and the bass was amazing as well. I really thought it was the most complete power amplifier i have ever heard HANDS DOWN. To me, this is a benchmark of an amplifier. This is the amp that others should be judged by. NOTHING is lacking and right now it is the #1 amplifier that i have ever owned.
My current amps are Mcintosh MC601s: i decided to give these 601s a try and they don’t disappoint. They have great detail, HUGE soundstage, MASSIVE power and great midrange/highs. The bass is great, but it is no pass labs 250.8 or 350.5. As far as looks, these are the best looking amps i have ever owned. No contest there. i gotta be honest with you all, i never bought mcintosh monos before because i wasn’t really "wowed" by the mc452, but it could have been also because at that time i was using a processor as a preamp which i no longer do. Today, i own the Mcintosh C1100 2 chassis tube preamp which sounds unbelievable. All the amps i just described above have been amps that i auditioned with the C1100 as a preamp. The MC601s sound great without a doubt, but i will say that if you are looking for THE BEST sound for the money, these would not be it. However, Mcintosh remains UNMATCHED when it comes to looks and also resale value. Every other amp above depreciates much faster than Mcintosh.

That said, my future purchase (when i can find a steal of a deal) will be the Pass labs 350.8. I am tempted to make a preliminary statement which is that i feel this amp could be THE BEST stereo amp under 30k dollars. Again, i will be able to say more and confirm once i own it. I hope this update can help you all in your buying decisions!

Man, you have been busy! Thanks for the insights and hard work!
No tube amps. Too bad
If you get a chance to wrangle an Ayre amp...even an old might very well like it a lot
TY- whitecamaross.
Great write up. If you’re ever in NYC and want to hear the BHK 300’s on a different system (since you seem to like them) I run them on our TAD CR1’S - feel free to message me. 
Also I'm about to put the 300's on Halcyonics type active vibration platforms under maple blocks.  I'm not sure what to expect.   have you tried any platforms with any of your  amps?

I've never used any platforms with my amps. I throw them in my rack and begin to listen. 
I will look at my pictures to see which amps I've forgotten to add to my review. I know I forgot to write about the plinius sa103, sa100mk3, Ati signature 4007, octave audio v110 integrated. 
As i stated above, my front end are the Martin Logan Renaissance, Mcintosh c1100 preamp. Someone mentioned above why not tube amps ? It's simple, I use amps as part of my home theater too and tube amps DO NOT work well in a home theater application. They don't have the dynamic swing capabilities that solid state or class d amps have. I've tried them and they get lost with action scenes not able to keep up with the rest of my solid state amps. If I was only a 2 channel guy then yes I'd try a few. 

My list also wouldn't include tube amps.
Tube amps are 'Aston Martin', 'Ferrari', 'Bentley'... in other words nice toys!
I like RAM 3500 dully -- a tool.
I was once introduced for very cheap to 'Load Invariant" amps and never returned back. It literally means that it does not care about load at all neither high or low. I never heard though anyone tried it with ML or any other panel speakers. 
Just a few comments. Comparing Dodge Ram to fine car = ignorant. Calling tube amps "toys" = ignorant. The term "Load Invariant" sounds like the marketing terminology used for Carver amps back in the day = some of the worst sounding amps I ever heard. Incidentally Dodge Ram = junk believe me I made the mistake of buying one recently.
I thought to that "Load Invariant" sounded marketing, but for some reason never returned back.
I do not compare RAM 3500 to a fine car, I'm just stating what I need and what makes sense. RAM does and Bentley don't.
What is the price range of these amps? I would think some are much more pricey than others.

Great overall review.. I like Parasound for value and quality combined. Cannot afford Pass....drats
Nice assessment of an odd analogy. 
Considreing you absolutely love the 250.8, wondering why it's the 350.8 you're longing for. The difference is 1.2 dB which i doubt is audible 
Curious if you’ve tried and compared any newer Class D amps? Not sure I saw any on your list. I think these must be included these days for a comparison of amplifiers available to be complete.

Load invariant is a good thing in concept. The devil will be in the details how well any amp accomplishes this. I had a Carver m4.0t amp for many years. It was certainly not load invariant and not sure it was ever advertised to be. Rather its thing was being designed to sound like a tube amp which it accomplished relative to other SS amps to a certain degree including NOT being load variant meaning it sounded very good with the right speakers but not so great necessarily otherwise.

Thanks white Camaro,

I appreciate you posting your impression of these various amps. It’s always nice to get someone’s real world opinion on equipment, especially comparisons.

Would you please expand on your impressions of the Pass XA 30.8 for us? What did it lack compared to the X 350.5?

i will be responding to everyone tonight after I get off work. I will also add a few more amps to the list. 

Thanks for the review whitecamaross,

did you find the XA30.8 lacking in power or were the X350.5/250.8 simply better sounding?

love to hear what you think of the Plinius SA100MKIII, I used to own one and loved it.

Also did you like the Outlaw Audio?

excellent informative post

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Common sense and experiences of others, would have saved your time listening to the duds.

They are all duds except the two pass lab amps IMO.
Alright guys, i just sat down and started to play these MC601s while i write what follows below:

Plinius SA100MK3: VERY AMAZING AMP. This amp has a gorgeous amount of detail and nice bass. i was very impressed by how much bass it retained even a low volumes which is a hard thing for many amps to do! I really don’t remember ANYTHING bad about this amp. It sounded very nice with my Dynaudio C4s.

Plinius SA103: I bought this amp because i thought the SA100MK3 was amazing so i had to try it. Anyhow, i found this amp very detailed, great overall tonal balance, BUT I DID NOT GET THE SAME OOMPH in the bass department that the sa100mk3 had. I called plinius several times and they told me this amp uses dual transformers and that i needed to re-wire my electrical outlet with a 12 gauge cable, etc, etc which i was not going to do. I felt this amp was a tad more detailed than the plinius sa100mk3, but if i am being honest here, i preferred the sa100mk3. It had bass that "thumped" at any volume level.

Octave Audio v110 integrated: i tried this unit with my Confidence C4s and i will say it REALLY impressed me when i first turned it on. I mean, it was like my speakers became something else. TONS OF BASS that i couldn’t believe what i was hearing. I liked it so much that i wanted to keep it and made it part of my home theater by using its passthrough mode. That said, it just didn’t really keep up with the rest of my amps. It got lost time and time again when action scenes came on. It almost felt as if my front speakers were not even playing at times. I later just realized that Tube amps just don’t have the dynamics and slam needed for movies. I must have tried all sorts of settings, calibrations, etc and i just couldn’t get it to blend with the rest of my set up. If i had a channel set up and no home theater, i would have certainly kept it.

ATI SIGNATURE 4007: Here i was again. Trying to see if maybe i didnt give the 6007 signature amp a fair shot when i first bought it so tried this less powered version. I found that it really is a solid amp if you are looking to do 100% home theater with occasional 2ch listening. This is the amp that you throw in a rack and shut the door and let it play for years and years and years without ever worrying about it. However, it is NOT IN THE SAME LEAGUE as the JC1’s, pass labs, Krell 402e, etc.

EMOTIVA SA250: I was actually very impressed by this affordable amp. i connected my crazy expensive mcintosh c1100 to this amp and i really was amazed by how it handled my electrostatics. I could say that there were other amps that were far more expensive and yet they couldn’t hold a candle to this amp. It had plenty of everything and i really thought if this amp was made by someone else, they could charge 10 times more for it.

Someone above asked me why i don’t try tubes and i think i pretty much said why above. I just feel tubes are awesome for 2 channel and i probably would have an all tube set up if all i did was 2 channel, but in my situation i need an amp that can excel at both.
As far as the xa30.8, that is one great amp. I think it is the amp you use if you live in a nice studio apartment with a nice pair of focal diablo bookshelves speakers or Dynaudio C1s (or something like those) and you do serious listening late at night without ripping your neighbors walls off. This amp will give you every ounce of detail and 3 dimensionality that you wish to have, but IT IS NOT a monster and dynamic amp as the 350.5 or 250.5. or 250.8. The xa30.8 is a very intimate sounding amp. It is not the amp that will make your jaw drop when you let it blast as loud as you can handle. That is when you purchase the x250 or x350.
i want to be very honest, and i want to put this out there. i find the XA pass labs amps to be amazing amps, but you WILL BENEFIT from having speakers with powered woofers such as martin logan electrostatics, goldenear triton 1s,etc. In my personal opinion, the best amps to come from pass labs are the CLASS A/B amps. Any X series amp to be specific. They just have outstanding slam and will knock you back in your chair when you crank them up. Up until this day, i still have not heard a better slam and dynamics than the pass labs x series whether it be the .5 or .8.

One last thing i wanted to say is that i am writing this out for all of you who are looking to gather as much info as possible in order to make a smart buying decision. However, my reviews here are based on my own experience and not what some reviewer got paid to say on a magazine. i don’t get paid, i don’t make anything from this. It is just my passion/hobby. Some of you will recommend other amps from brands that nobody has ever heard of or that are so unknown that i simply won’t dare to buy. Why? because as you can see i go through amps almost on a weekly basis and i also need to be able to sell them when i want to try the next amp. Does this mean that i am missing out on a lot of other amps? i am sure i am, but i am also being smart about my buying decisions. Essentially the sale of each amp finances my next amp purchase. i can’t buy an amplifier that i simply can’t sell for 3, 4, 6 months etc.
One more thing i was thinking about doing was to give my opinion on processors. I have owned quite a few as well and can certainly give my personal opinion on many of these, but that will come later.
Anytime you see something that i am selling, rest assured it is only because i am looking to move on to the next thing and not because there is something wrong with it. I could be totally in love with an amp today and think it is the best I’ve owned, but i will still move on from it when something else catches my attention.
In the meantime, i will continue listening to these 601s.

@whitecamaross - I would definitely welcome discussion on the different processors you have reviewed. I would ask that you start a thread in the "Home Theater" subforum. I would definitely comment as I have been through a number of processors as well.

I see you have very positive review of the Emotiva SA-250. Have you listened to the other XPR/XPA monoblocks? I have not heard the SA-250, but if I remember right, it’s basically a single-ended amp - but has separate power supplies fed from a shared transformer. The XPA/XPR monoblocks are fully balanced/differential with larger power supplies and more output transistors. Just curious. The XPA amps sound somewhat bright/harsh in the highs. The XPR amps sound a bit soft, but a bit cold at the same time (yes, I know it’s weird, but it’s my impressions). The stock fuse is the problem on both amps, as replacing them with Isoclean really helped each amp significantly. I’m running all XPR-1 monoblock just because I can’t find any other "equivalent" amp near the price range that will give me as much.

the XPR monos were on my bucket list, but they are long gone now so that won’t happen anymore. I almost bought a pair of xpa-1 the other day, but i just didnt do it because i am still playing with the mc601s.
What i think emotiva benefits from besides what you mentioned above is from an excellent source and preamp/processor. I think my mx160 processor (which i am selling on here) sounded spectacular with these emotiva amps. I tried other amps i had here and i honestly couldn’t tell them apart. The mx160 made those emotiva amps sing amazing. People sometimes underestimate the importance of a quality preamp or processor. Right now, i am a believer in a tube preamp with a solid state for a 2ch and home theater application. It is tough to beat. 

You mentioned somewhere in one of your posts a second set of speakers ? Are you using both sets of speakers for these trials ? Are these impressions of the amps for just with ML or both ? One might not get the same results once different speakers are introduced . Different pre's /processors will affect the way a amp sounds as well . Lots of variables to put a blanket statement on a amps qualities .

Have you ever used a Krell FPB 400cx or 300cx, and if so, how would you rate their audio quality vs the Pass 250.8, particularly in the area of bass slam and articulation? 

The reason I ask is that I some time ago acquired a FPB 400cx with a view to achieving awesome and prodigious bass and bass slam.  However, I have not found this to particularly be the case.  The 400cx actually replaced a McCormack DNA-1 Deluxe Edition, and I think does sound better, but not as much as I had hoped. 

I have recently actually been getting the bug to upgrade my speakers and/or speaker cables in an attempt to get more bass extension, slam, control, and articulation, but your posts about the Pass amps providing those very qualities has me interested.  Perhaps I am barking somewhat up the wrong tree here with respect to a speaker and/or speaker cable upgrade.  But then, otoh, some people say quality amps mostly sound similar and I might waste $10K on a Pass amp and not find much more bass and slam than with the Krell FPB 400cx.  Thoughts?
Starting with the bhk300s and below that list above, I've used the Martin Logan Renaissance. I no longer own the c4s because the minute I heard the Renaissance, my jaw dropped and went home and immediately listed my c4s. It was a day and night difference. 
As far as the krell amps that someone mentioned above, no I haven't heard those. I don't find krell to have the bass that magazines rave about. I've had a lot of krell amps and NO OTHER AMP in my room gave me more slam than the 350.5 or 250.5 or the jc1s. Those are my top 3 amps when it comes to bass. 
Thanks, ss!  So, are you saying with respect to bass and bass slam, Pass 250.5 > 250.8?   Or are they comparable in that arena?  Important to know, since these bass qualities are currently my top factor.  And also since I think either the Pass .5 or .8 would be a big step forward in mids and highs over my current Krell.
I will put my sunfire signature head to head with any amp!
Pass labs x350.5 demolished my krell 402e in bass and midrange. The krell sounded flat and had zero fullness. The 250.8 is better than the 350.5 
Thanks whitecamaro. Enjoy your music!
Very interesting read.
Thanks for the time and effort you put into this project and sharing it with the group.

The xa30.8 is a very intimate sounding amp. It is not the amp that will make your jaw drop when you let it blast as loud as you can handle. That is when you purchase the x250 or x350

Regarding bass slam, I wonder how the XA100.8 would compare to the X250/260/350.8? (I have Maggie 3.7´s)

Great information, thanks for sharing. My question is how did you manage to go though so many amps in such a short period of time? Buying and selling on-line is a hit or miss approach at best, at least in my experience. Not mentioning how expensive it can get if you get stuck with an item. Whatever you're doing seems to be working for you...Keep these reviews coming....
Thank you whitecamaross for the time and effort you put in !! Really appreciated.  Real world experience by a user that describes sound of an amplifier in a non bias way is very valuable!!!  I have been on a search for that rounded sound with a nice bass kick to it and musicality and I finally found it in Pass Labs 250.8 thanks to review made by whitecamaross.  I tried emotiva 5 ch gen 2 was OK,  then moved to ATI 6003 signature series based my decision on all the awesome write up found on the net by known websites that review amps and the sound produced by this fine amp was not my cup of tea to put it mildly (I totally agree with the feedback whitecamaross wrote about that amp spot on). Anthem Statement P5 sounded nice from what I had so far but it still was lacking clarity and oomph I was seeking. Then I took a plunge for the Pass Labs 250.8 never heard it before just based my decision on review by whitecamaross and It is the ONE.  LOVE it, the sound I crave. It is hard for me to imagine how much a sound can get better than this!!! 

I keep saying it again, if you want slam and dynamics with fullness to the sound then you should stay away from the xa series from pass labs. Those are amazing amps but they are more for classical or instrumental music or if you like amazing midrange. They don't give you the bass attack or punch that some of us like. 
As far as how I can do this and constantly buy and sell amps, I am very well connected and have had tons of relationships with many dealers. I have long and good standing relationships with them so there is no problem there. i also send them many of my friends to buy from them. 
Ottablue, I am glad you liked the 250.8. I told you it was killer !! Glad you bought it from me and I didn't really have enough time with it but it was enough to hear a massive improvement from all other amps I've owned. 
I just got finished listening to the Mcintosh mc452 and will list it for sale soon. Review coming !
I'm curious where the Sanders Magtech would fit in to your comparison.
I'm probably never going to buy that brand . As stated above, I purchase amps that I don't have a hard time selling down the road. I'm sure there are many amps out there that are excellent but being that this is an expensive hobby, I can't buy something that I can't get out of once I'm done with it. Another perfect amp that I'm curious about would be the Magnus audio line of amps. Those are on my taste buds but after doing serious research and talking to a few well known people, that's an amp you buy and keep because it won't sell and that's not something I'm willing to do. 
I’m probably never going to buy that brand . As stated above, I purchase amps that I don’t have a hard time selling down the road. I’m sure there are many amps out there that are excellent but being that this is an expensive hobby, I can’t buy something that I can’t get out of once I’m done with it. Another perfect amp that I’m curious about would be the Magnus audio line of amps. Those are on my taste buds but after doing serious research and talking to a few well known people, that’s an amp you buy and keep because it won’t sell and that’s not something I’m willing to do.

I thought Magtechs are rarely on the used market for long.
That doesn't really make sense. It sounds like you want to be on a never ending search for middle grade amps that don't really satisfy you as long as they are re-sellable. Why not find one that's really good, save up the funds for it and live happily ever after. The merry-go-round of components does get tiring after a while, and at some point, it will just be
different flavors of the same thing.
How about you all think of me as the guy who spends his own money to try amps and give his personal opinion so that you all don't have to spend your own money going around trying all sorts of amps ? Isn't that great for most of you ? At the end of the day you all come on these forums doing your own research about a component you are curious about trying so my thread does exactly that. It gives you preliminary information about an item you are unsure about. I leave my feedback and you guys do your own analysis as to weather what I say makes you reconsider your next amp choice or it just confirms that you are buying the right amp. 

The reviews are helpful as long as folks have similar speakers - fairly power hungry electrostatics, e.g., ML, Maggie, etc., needing big head room and usually set up in a large room. So to help the rest of the folks, you'd need to have a separate setup with efficient speakers and mid-power tube components.
The Quested Power Amplifiers designed for Studio grade stuff both in the UK and USA. Used by the big man himself Hans Zimmer. They are warm sounding and very transparent fatigue free. Like your self iv been through tons of multichannel amps and can say so far these are the best sounding and will drive difficult speaker loads. You will need multiples as the most channels you can get in a single amp is 4. I would run multiple amps for a high end theatre.
Thanks a lot for sharing these informative reviews, whitecamaross. You certainly make me want to try a Pass x250.8!

Plinius SA103: I bought this amp because i thought the SA100MK3 was amazing so i had to try it. Anyhow, i found this amp very detailed, great overall tonal balance, BUT I DID NOT GET THE SAME OOMPH in the bass department that the sa100mk3 had. I called plinius several times and they told me this amp uses dual transformers and that i needed to re-wire my electrical outlet with a 12 gauge cable

While it sounds like a dodge for Plinius to say you need 12g wiring to get this amp to perform, I think they might be right. I have mine fed by its own 20-amp dedicated line via 12g Romex, into a Furutech GTX duplex, and the bass is superb--deep, textured, weighty.

I had my SA103 upgraded by Vince Galbo, which improved everything, especially the top end, which I felt was slightly rolled before. But the bass was always beefy on the dedicated line--maybe best thing about the amp before the upgrade. Vince also said 12g electrical wiring was needed for the amp to show its stuff. It’s amazing to me what a difference dedicated lines make in high-powered amps--and in everything audio, really. It’s too bad, in a way, because they’re not always an option.

Agreed Bill. Plinius is grea stuff but not everyone is going to be spending the extra money to upgrade their electrical system etc. Plinius should think about these things. To me, the 100mk3 was better sounding with my dynaudio c4s. The bass was better. 
Nothing beats the pass labs 350 or 250 in terms of bass though. It's a game changer. I felt as if all of a sudden the bass was more energized and deeper without me touching anything else. 
Pass labs is the top of my list at this time. Overbuilt, amazing in every way but they do run warm and don't fit in racks so there's a compromise there. 
white have you tried any of the newer class D amps? Mola Mola? Merrill Veritas?

No i haven't. I've only had the theta dreadnaught d and It was ok. 
Thank you for trying those many amps and for sharing your impressions.
I just finished an amp search on a much smaller scale, including an NC1200 amp like several here have asked about.
I have not tried the Pass amps you like so much but I do agree with NP's thoughts on the importance of a strong power supply so I am not surprised they sound so good.
The amps I ultimately selected to live with, Clayton M300 Class A monos, have a tremendous power supply, double their power into 4 ohms and sound tonally rich and powerful throughout the entire frequency range.  They may not do well on the resale market, but it doesn't matter to me because I will not be selling them.  I would however like to hear the X350.8 stereo and X600.8 mono amps.

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+1 for Parasound Halo JC1 mono’s, John Curl desigded beauties one of the hifi "gods"

Best bang for buck you can get if you have semi hard or stupid hard (Alexia’s) to drive speakers, and the high bias class A switch is a bonus when your listening seriously, if not, leave it off and save power.

Cheers George
It would be interesting to read your take on the Merrill Veritas. They have a 30 day trial offer. I do not have the proper speakers to try with them myself so I need to go with online reviews.

I would love to hear someone with the amp background of this thread originator do a comparison of amps like Mola Mola, Merrill Verita, and Theta Digital Prometheus. How good are these new amp designs relative to the status quo
Just curious , why such fascination with the bass response? I would have expected more natural and linear frequency response be more important criteria than bass performance. I like bass as much as the next guy but certainly wouldn't pick my next amp based on that criteria alone. Same goes with choice of speakers. I heard a pair of monitors the other day dropping at 50Hz that (almost) made me put my speakers (30-25K) up for sale. Is it because of the type of music - rock vs. Jazz, etc., that is played using these amps?