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
NAD M25
PARASOUND HALO
PARASOUND CLASSIC
KRELL TAS
KRELL KAV 500
KRELL CHORUS
ROTEL RMB 1095
CLASSE CT 5300
CLASSE CA 2200
CLASSE CA 5200
MCINTOSH MC 205
CARY AUDIO CINEMA 7
OUTLAW AUDIO 755
LEXICON RX7
PASS LABS XA 30.8
BUTLER AUDIO 5150
ATI SIGNATURE SERIES 6005

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!


128x128jays_audio_lab
techno_dude,
Welcome back.  In the spirit of an open mind, listen to the GTA speaker.  It is superior to any dynamic speaker in every way.  I don't know if there are any Canadian shows near you where GTA could be shown, but it is worth a trip to Massapequa, NY (Long Island) to Steve's house.
Glad to discuss with you again Viber6, and others, with respect. ( not easy for everybody, specially RIAA who sees trolls everywhere when his ´´big gear ego ´´ is challenged ).

I do like the GTA speakers, a much more purist approach than ML. And also their reasonable msrp... 😉

Like you said, in the spirit of an open mind. That is why the Pass Labs XS recent praise here has to be taken with a big grain of salt... specially in a completely new speakers and room context...
I just picked up the boulder 2010 preamp. I will give my initial impressions later on tonight !
Pictures of the boulder 2010 have been posted. It took a big effort to find it in black color. Only a few of these were ever built. 
The big shootout is between Boulder and Merrill for neutrality and clarity.  This has never been done except by WC.  First, the 2010 vs Christine preamps, then Boulder vs Merrill amps.  I don't know why the flagship Boulder 3000 series has not been updated with the newest circuits which are in the 2160 and 1160.  Anyhow, these evaluations should be historic, between the finest examples of class A/AB vs GAN class D.
Thanks for your input Viber6.
I just want to clarify that the GT speakers you heard as much as you liked them pale in comparison to the new drivers in the 3.2 model.
In general the membrane - which is crucial to the performance of the driver not resonating at high SPL levels has been redesigned and reconfigured- unlike ML, Apogee, Analysis Audio, Aylsavox and Maggie the membrane is not solely Kapton or Mylar. Even the last generation model as you and Jay heard can play at high spl’s with no distortion or resonance.
Also we are looking into a design for the new model that will be breathtaking - possibly Glossy Ebony Macassar with Brushed Stainless in between or separating the front and back of the speaker. FYI- the new drivers were installed in our older model design speakers at CAF and can be heard at our Showroom in Massapequa.
The point being all prior owners of the 3.1 speakers can upgrade to the newest driver that will be in the new design.
Boulder 2010: (Zero warm up time )
-imaging intensity as no other component
- mids are dead center with clarity and articulation
- "zero filters " applied by this beast
- soundstage not as wide as ref6
- no harshness of any kind ( ref6 added some brightness )
- digs deep in the recordings trying to uncover everything hidden
- clarity and a feeling of "cleanliness" not heard by me from by tube preamp
-speed & dynamics in spades. 

Lastly , aint no way in hell a dac can do a REAL preamp's job.  

I could be mistaken but each time you’ve compared the Ref 6 with something, you’ve always said it had a wider soundstage. It seems like a lot of audiophiles value this above most other things. I’ve got a 2110 incoming and have a Ref 6. I’m really curious to see if I hear the same thing in my setup, with the soundstage. 
Cool WC.

Can you do a shootout between the Christine and the 2010, on the same amps. So that we can know he differences between them.
An elite solid state preamp shootout that would be very interesting.
WC,
It seems that in the early going, you really like the Boulder 2010 for its neutrality (I guess that "mids are dead center" means neutral, not warm or cold) and clarity.  No sterility or coldness so far.  I forgot whether you previously found the Boulder 2060 amp sterile in your home system or whether you made that assessment at a show or dealer.  So you might want to try the latest Boulder 2160 or 1160 amp.  For now, see how the 2010 and Christine preamps compare using the Pass XS300, and then the Merrill 118.

Also, viber7 in his post about Merrill 118 and CH Precision, said that the CH had the most accurate depth presentation by its true revelation of an instrument 30 feet away as sounding like it is 30 feet away, instead of the euphonic inflation of depth like a football field.  This concept of true-to-life soundstage describes the accuracy of a solid state Boulder vs euphonic inflation of tubes like Ref 6.  I've never heard the Ref 6 but have experience with several tube preamps including ARC SP6B and tube amps to know what tubes do.

Hello WC, 2010 staging width/depth are bound to increase with warm up and re-break in... Yet, so many good things from dead start are promising all by themselves... Any idea how much music playing has your 2010 unit had since it left the factory?


G.

 


Guido,
We'll await WC's answer, but I suspect his 2010 is a used unit.  The 2010 has been replaced by the newest 2110, whose circuitry is faster and has been long in development.
My 2010 is a few years old so it's been broken in. I am impressed by it in many ways but I need to put it through the motions with other amps etc. 
The boulder 2060 was sterile and cold but the preamp is like a wire with gain. It doesn't inflate the sound and although I do like the big sound of the ref10 and ref6, I could see myself begining to shift my mind into more accuracy and with "just the facts" from a preamp. 
I heard the boulder 3060 with this preamp and Wilson audio Alexia 2 and it was an incredible amount of bottom end control with good detail but I didn't really fall in love with it and I don't know if this because the Wilson sound isn't winning me or if it's that I just prefer the beryllium tweeter of the focals. A friend of mine says I am a beryllium lover. 
Christine vs boulder 2010 impressions will be coming soon ...  The one thing I can say in advance is that they both sound clean and clear like water. 

Thank you Viber for info on newest Boulder Pre... If WC's unit is used, and has been previously broken in well, it should take only some 10 days of grinding a signal to bring it back to its full performance level. I am looking forward to reading WC's periodic updates on his 2010.


G.

   


Boulder 2010 does not like the shunyata Denali at all. It sounds better with the nordost odin and plugged straight into the wall. It feels bigger sounding with more imaging and more relaxed sounding when plugged into the wall. This is getting very interesting. I didn't expect this at all!
WC,
"Boulder 2010 does not like the shunyata Denali at all. It sounds better with the nordost odin and plugged straight into the wall. It feels bigger sounding with more imaging and more relaxed sounding when plugged into the wall. This is getting very interesting. I didn’t expect this at all!"
The above paragraph is really what high-end is all about. "We" focus so much on individual parts with audio that many of us are missing the forest for the trees. The Denali works great with other components, but not with the Boulder 2010. Building a "system" can be complicated and more often than not we blame "speakers" or the "amplifier". There are many great components at different price levels. It’s just a matter of putting the "right" components together to get one’s preferred sound. Much easier said than done!
WC,
My Denali focuses the whole sound spectrum, creating a thinner sound but preserving the coherence.  It is possible that you don't yet accept the thinner sound of the 2010 mated with the Denali, and prefer the more relaxed fuller sound without the Denali.  I don't think the issue is Denali compatibility, but comparing the 2010 vs Christine under the same conditions, with or without the Denali, should resolve this question.  It is also possible that even though the 2010 has lots of time on it, it may take days for the 2010 to achieve equilibrium, as Guido says.  After this short period, you may find that you prefer the Denali on the 2010.
Could be. Maybe this preamp will stabilize over the next few days. One thing to note is that this preamp runs warm to the touch. It's the first solid state preamp that runs this hot which is surprising, but I guess it is due to the "class a" design. It actually runs as warm as the boulder 2060. 
Negative. Not all preamps have this design. Typically this is stated on the manual or somewhere. 


Last night I brought the focals in a little closer to each other and the sound improvement was beyond belief. I am about 10ft away from them and they are about 7.5-8ft apart as opposed to 9ft. They are 5 feet away from the front wall and about 4 ft from the side walls. 
Just curious if you tried the Pass int 250 integrated? It has the same power section as the int 250.8 (which you rated very high) but it has a preamp custom made for the int 250. All reviews I’ve seen on the int 250 were highly complimentary. Especially within it’s price range.
I have found that any speakers I have used, when brought closer together, will focus the image better and provide more accurate, life-like clarity.  Of course, there is less separation and a smaller soundstage. Many people with panel speakers like Maggies will place the ribbon tweeter on the inside and the midrange/bass panels on the outside.  The separation of the overall speakers is the same, but the less separation of the tweeters will focus the HF better.

Gradually bring the Focals even closer, like 5 feet apart.  You will get highest clarity this way.  The separation will be not bad, but you will find yourself closing your eyes, enjoying the clarity, not caring as much about where the sound is coming from.   
You should avoid setting the speakers farther apart than the distance from each speaker to the listening position. 
Grey9hound refers to the familiar equilateral triangle positioning.  This is a 60 degree angle.  I like a 30 degree angle, or 5 feet of speaker separation at a listening distance of 10 feet.  Also, this gets the speakers further away from all walls, offering a more free, airy sound.
Proper speaker positioning in a room is equal to an equipment upgrade and is never given enough credit in a system. Many audiophiles just keep buying new equipment rather then spending the time to properly set up there speakers and it takes alot of time.listening and research.

Keep playing with them WC it well only get better.
@whitecamaross 

There's a Simaudio 860 V 2 for sale on the Gon right now... 👍

Hope everyone had a nice Thanksgiving... 🍻
Mr. White Camaro sounds a lot like me, We definitely have some things in common. But we also see things a bit differently. Just to say, "If", I was to write my amp list? Um, It would be quite a bit longer though. I only slowed my pace going through amps for two reasons. 

1. I have found some amazing gear! 
        But the main reason is actually:
2. I have run out of room!. As in "Stacked" as tall as safety and common sense would allow. "This includes several, very large, very secure as well as "climate controlled", storage units..
 I had been selling as fast as I could but my "Collection" over time became, Very, very specific. As in; "And this is just one example". 
There is a particular vintage amp of which I own a VERY large number of. Each amp after purchase was tested and evaluated by myself. Both on a "Test Bench', as well as integrated into my, "Rig". and listened to exhaustively. then off to one of my, "Amp Guy's". Then into the "Stack".
   By the way, "This is what I do. This is ALL I do". 
Anyway, I have the largest collection of this particular amplifier on the planet. At one time I did part with about 35 of them a few years back.. But the rest? Not quite yet, "For some reason! And every single one? Each is basically "Perfect".
    Now, This amp is S.S., And for it's time very well powered. But not anywhere as well powered as my Pass X-350, Let alone my MC452.
 Those two are indeed my absolute favorites as far as SS amplifiers go. 

 As far as home theatre is concerned? I shifted away from that a couple of years ago. At one point I had 28 separate power amplifiers running my 17.8.6.9 Home theatre system. That number of ampsdoes not include the "9", x 1500W, Class D amps, running my "9", servo controlled sub's. "At one point that was (12), Servo Controlled Sub's"! "But size restrictions were becoming quite apparent at that point in time".  And believe me, "Servo Controlled Sub's", which utilize a control system through "Actual", measurement by a "Laser Accelerometer" and "Mirror" system attached physically to the woofers cone? Are "FAR SUPERIOR!", to most modern subs, which are CALLED "Servo Controlled". But which, "IMHO", Are in fact, NOT "Real" servo corrected sub's at all! 
Like the one's from, "Rythmik", and "Velodyne", and other brands. Which uses either a "Open OR Closed, Looped Feedback Circuit", Which see's an DC voltage as an "Electrical signal" Which is a "Pulse Width Modulation" or "PWM" which they then, "Call" , a measurement. It is then processed using an algorithm which 'Averages" the correction and is not an ACTUAL true correction from an ACTUAL measurement! Manufacturers Spec., OR, "Best Guess", for their so-called, "Feedback Loop" correction system. As they call it is all that they use!
    Basically all these companies have gotten away with changing what "Servo Controlled" actually means over the years and it was always meant to be in the audio realm.. They have done this by utilization of a slick math program and an averaging algorithmic calculation!  Why? Because doing it right is hard and expensive! "I have a servo controlled, Transmission Line, Sub" under development but currently use three "Martin Logan", "Descent's", They are, actual servo correcersubwoofers in my now "2.3", Stereo System.
    So, In conclusion about servo controlled sub's?
  "IF", it doesn't have a way to "Physically" measure the wave producing surfaces movement. "As well as see and measure it's underthrow and overthrow"? It is just a type of very fundamental "AI". A program "guessing" about what the correction should be and then applying it. . 
    "You have been warned"!
  More later, unless this isn't well received....
       Scott
Update :
Just moved the power supplies of the amps closer to the outlets in order to use my 1.25m nordost odin powercords on them and use the cardas xl powercords on the dac and preamp and here's what I found:

Lost bottom end oomph 
Gained air and an organic feel 

I can conclude that the cardas xl powercords have an insane amount of bottom end with great noise filtering so if you need more oomph with less noise in your system then give them a try. I personally might keep using them on my sources because my focals already have tremendous bottom end so they don't need more bass. 

Hello Jollygreen,

 Mr. Camaross, sorry for the brief detour;

I have a servo controlled set of subs, 2-4stacks OB with 12 inch drivers from Rythmik, very similar to the GT set up except I built them myself and I believe them to be excellent bass reproducers, they load the room evenly and I think that they integrate far better in most rooms than most if not all non-servo subs that I have heard, why the knock against them if they achieve what they're suppose too, who cares how they get there??


Don

Hello @Whitecamaross, as you know, I have been singing the virtues of Cardas Clear Beyond XL power cords for quite a spell... In my system, they are the most balanced, quiet, awe-striking, and in general musically satisfying power cords for most of my components. Only on my Esoteric X-01 I prefer the Cardas standard Clear PC over the XL, as the standard Clear yields to the CDP some greater agility.


Regards, G.


   

So yesterday i spent the entire day moving my power cords around to see where they would sound best and the results were extremely good.
Today i am borrowing a Shunyata Sigma NR which i will use on my preamp or dac to see if it will outperform the cardas xl that i own. Anyhow, although i did improve things a bit with this exercise, i decided to just move the speakers about 1 foot closer to my listening spot which leaves them about 6.1ft from the back wall ,10 feet away from my chair and approximately 4-5 ft from the side walls. Let me tell you, moving the speakers one foot closer was a revelation. It feels as if i just changed my entire list of components with something else. The soundstage is now bigger, deeper, better imaging, more air and it feels as if i upgraded to the bigger maestro or stella focal. What is interesting about this is that the speakers (without me knowing at all) ended up being almost at exactly 1/3 of the length of the room. i wasn’t aiming to be at 1/3 of the room by the way, but after moving them around they just ended up there. This particular set up would present issues for those of you without a dedicated room because having a speaker 6ft off the wall is not practical in most living rooms, but i want to urge you all to try this:
Divide the length of your room by 3 and then place the back of your speakers at exactly that spot and let me know what you all hear. If possible, your seating distance should be 1.5 times the distance from the back wall so let’s say you end up with the speakers at 5 feet from the back wall then do 5 x 1.5 and the result should be your distance from the speakers. Give it a try and report back if this is working as good as it has for me.
Excellent.  Now try the speakers a little closer to each other, which will increase the distance from the side walls.  This will increase the same benefits you have achieved with greater distance from the back wall.
I'm glad you feel so strongly and positively about the 250.8. I've ordered the int 250 and they share the same power amp. I know the int 250 has a custom preamp but I'm hoping they share similar personalities.
Anybody here  ever compare the Wilson alexx against the Alexia 2???
I’m extremely curious about the alexx. Some say it is the best price / performance speaker Wilson makes today. I’ve been told it is even better than the xlf. Wilson owners please chime in or anyone with "seat time" with both speakers. I’m starting to seriously contemplate the Wilson alexx.
Try toeing the speakers in abit WC and another 6-8 inches more into the room away from the back wall.

My speakers are 8,2in into the room and 5.3in from the side wall.8ft apart.
I have a pass labs xp30 coming in next week. Next shootout will be my boulder 2010 vs pass xp30. The reason why I bought it is because I need to see HOW the xs300s would sound with their own preamp. I don't have a way of gauging how good or bad the boulder 2010 is in terms of synergy with the xs300s. The xp30 will be my foundation in terms of the pass labs house sound and a good starting point. From here , I'll be able to know exactly what other preamps bring or don't bring to the table. 
Did not the Christine bring more quickness, a window that was super clean and 3D to the xs300's?
$$$ at this time. I've got more stuff than most dealers have on their floor lol. 
I tought you had already compared the Christine pre.with the Boulder 2010. Maybe too quick a shootout to conclude anything sure. It’s ok, things need to move sometimes.

Pass XP 30 vs Boulder 2010 should be very interesting.

For some reason people totally dismiss pass labs preamps and I really don't know why. I've owned their preamps and I was very impressed. 

We got the best results with the matching XS pre on the XS 150’s.. Truly amazing.
@whitecamaross 

I do not own Wilson, but have access to most of it at my dealer, and he is less than five miles from my house. He has Sabrina up through XVX. I visit often and was there about a week ago.

Alexia 2 vs Alexx. It is absolutely no contest, Alexx is way better. No hyperbole here. I've heard both with ARC and D'Agostino, and no matter what amplification was used, the Alexx is simply much better. Alexx is also a lot better than the Alexandria XLF. The XLF is a bit older design I believe; I've heard them with ARC and one other amp that escapes me.