Review: Tube Research Labs Samson monoblock amps Amplifier

Category: Amplifiers

This is a review of the latest solid state, mono-block amps from Tube Research Labs (TRL). They are named Samson by the builder Mr. Paul Weitzel of TRL.

Please to go my system link below to better understand my room set-up and ancillary equipment. This will help you better understand the full context of my review.

I also encourage you to look at the long list of amplifiers I have owned or listened to extensively in my home system over the last 5 or so years. I have been very active on Audiogon as demonstrated by my feedback and long list of amplifiers. I have been fortunate as I have sold gear for audio friends who had wonderful gear. This has enabled me to play with some fantastic gear over the years.

Finally, I listen to female vocalists, jazz, a little classical, piano and guitar instrumentals, contemporary Christian and alternate adult music. Some of my favorite artists include Van Morrison, Beth Orton, Sarah Groves, Aimee Mann and Rickie Lee Jones. I like to listen with the lights off and often with my eyes closed. Music is the way I relax and get away from all that fills my head in a given day.

Samson mono-block amps

I am not a technical person and will do my best to tell you a little about these amps. Please call TRL if you have questions as I can report on my experience with these amps only.

-Paul states they put out close to 300 watts per amp.
-Mine are single ended, but think Paul can build yours as needed.
-No fuses as TRL employees a circuit breaker as the on/off switch.
-They always run cool no matter how long or hard I drive them.
-Very quiet – no real mechanical or chassis noise.
-See my system pictures for cosmetics.
-$5500 for the pair
-Shipped in a custom made wood crate very well padded and secure.

My experience with the twin Samson amps

Let me say upfront that I do enjoy trying new gear and hearing the differences between components in my system. This was never a hassle to me, but fun. This has now changed as the TRL amps make music in a way that no other component has conveyed. This was true of the TRL S225 integrated amp and now even more so with the new Samson amps.

We all try gear and notice that this one sounds more transparent and that one has more midrange warmth and on and on…….. They do all sound a little different and sometimes greatly different. Some certainly outperformed others. I even recall saying one “killed” another with its overall performance. However, looking back they all had some limitations and in one sense they all sounded alike – like reproduced music. Here is where I begin trying to share my experience with these Samson amps in relation to all others I have enjoyed.

For me the Samson amps paired with the Dude tube preamp (TRL) broke through a sound barrier I truly thought was not even possible. This is why I am no longer compelled to try another amp flavor.

So, in what ways do these amps break new ground? Ok, this is a time where those standard Aphile descriptions just don’t reach far enough. The Samson amps are the standard for neutrality, imaging, bass authority, transparency, tonality, extension at the frequency extremes and so many other attributes based on my experience. Fellow music lovers let’s move beyond the elementary and onto the real deal.

Musical instruments and voices now sound live and not bound by the constraints of hardware. My words will fall short of my experience here as this really must be heard to be fully understood. The piano is now released in my music room. It sounds so live and un-reproduced. It sounds real and so right. The attack of the keys is alive and full of energy. The body of the instrument is palpable. Every key stroke is discernable and presented with utter clarity.

Kick drums come alive with impact, energy and realism I have only heard at the best live concerts. Voices flow with a sense of space and dimension that literally places the artist before you.

Even my most complicated jazz recordings come alive with discernable instrumental lines that were previously completely lost or blurred. Background notes, vocals and phantom sounds now BECOME part of the music. You must hear this first hand!

Does it sound like a tube or SS amp? My answer is very simple. It sounds like live music. I don’t even think about that notion with these amps. It seems so off point now. Please keep in mind I mate these amps with a nice tube preamp (review coming).

Never do these amps even hint of being compressed or strained in my system. My 8 ohm speakers are 90db efficient and I play music as loud as 102 db at rare –very rare times. The music grows in size as the volume is turned up. It never shouts at you screaming “I’m very loud”. Rather, music swells and its impact is awesome to experience. The other powerhouse amps I have owned are boys in this regard. The Samson amps are men. They are always in complete control adding to the live musical experience.

Yes, you will hear music previously lost in your system. Yes, there is air and space around each instrument as music floats from the blackest background imaginable. The Samson amps are state of the art in this area. They are pure magic to experience. I hear a whole new dimension to the music in my room. I can close my eyes and get so lost in the music. I feel and sense the piano behind the sax player over to the left and Van the Man just turned his head in the studio!

I will end by saying the Samson amps delivered music as I have never experienced in my dedicated room. They broke though a performance ceiling I thought all amps had in common.

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Click to view my Virtual System

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6017afa4 4738 4a9a bf4c 2da38b5f3955grannyring
Nice review Bill. That's a very impressive list of amps you have there. Glad to hear the TRLs are working out for you.
Nice review, Bill. Though I’ve known about the Weitzels and TRL for some time, I’m relatively new to owning their products. I have a Marantz 8001 CD/SACD player that Brian hot-rodded, and I couldn’t be happier. It’s truly a special player, and one that shares a common trait with all other TRL gear I’ve heard: It has a spooky way of getting out of the way of the music—to let it flow in a very continuous manner, unimpeded by electronic hash, haze, and other nasties. It has a tremendous sense of resolution and dynamics, but is able to deliver all that within an addictively sweet, musical envelope. Sounds like the Samson is the same way.

BTW, have you ever tried Brian’s Shine Ola? I kinda dismissed it when I first tried it years ago, since it didn’t seem to have as dramatic an effect as some treatments I tried, but I’ve recently returned to using it on all my discs. It just seems to have the “purest,” least colored effect on the music. It’s improving but not necessarily CHANGING, which is a good thing in my book. That “first, do no harm” ethic seems to translate to the Weitzel’s gear as well—very uncolored, very neutral, and very, very good.

Again, nice write-up.

I will have to get some of Brian's Shine Ola' as you say. Your player is awesome as Brian told me he likes it better than my Sony with battery power supply.

These Samson amps break new audio ground in my book. They most likely won't ever be reviewed by the big Audio mags, but I know first hand they eclipse several top rated amps by a wide margin.

What amp and pre are you currently using?
I've used Shine-Ola exclusively since I had my DAC modded by TRL a few years ago. I also use the Record Research Labs (now MoFi) vinyl cleaning fluids that Brian manufacturers. The products are simple to use and effective.

Another effective accessory with TRL gear is Quicksilver Gold paste manufactured (with Brian's input and testing) by Xtreme AV. I tried some on the spades of my CRL Silver speaker cables (the original version designed by Paul) and the results were impressive.
I’m without a main system for the moment, so no amp/pre to speak of. I’m using the 8001 in a small second rig with a Dussun integrated amp, Jena Labs cabling/conditioning, and Definitive Technology speakers. When I get a main setup going, it’s probably going to be built around a high-quality integrated of some sort, likely solid state.
Hooper - If a solid state integrated amp is what you're after, add the TRL ST-225 integrated to your list.
Hi Bill,

You finally found the end of the road and hopped off the merry-go-round for good ?

Kidding aside, I know how difficult it is to describe an experience that's different from all the rest.

You expressed that difference quite effectively to me on the phone and by your previous posts.

It was not hard for me to understand, because this is what I was looking for all along
(the audible illusion without listening to the equipment) ?

TRL's extensive R&D experience and track record for being nothing less than the best puts me in a no-brainer decision maker, the Samsons will be in my system when things pick up here, that's for sure.

Paul and Brian kick butt, no doubt.

Great review well done, Merry Christmas and Happy Holidays !
In fits and bursts I've been formulating a review for my Samson Pair. I've read your review several times Bill and wonder if I can add anything substantive.

Everything said here is absolutely true. I've had multiple commercial amps and various iterations of Musical Concepts modded Haflers -- the final quite radical and excellent. The Samson is not simply on another level, it is in another existence. This may sound excessively purple, but it is true.

I'm compelled to add something about the First Watt, a zone critical to my listening habits.

I frequently listen at very low late night levels (sleeping wife) and the Samson retains its qualities all the way down to virtual inaudibility. There is no shrinkage of the soundstage or sense that the stage is receding. Even the incredible bass extension and weight are somehow preserved.

All the audiophile requisites are there and become secondary. I am a severe amp cynic and these things are simply unbelievable. My closest contender is a Clayton S-40.
This Clayton is outstanding, one in which I thought could not be bettered. It has been -- quite mercilessly.

Job well done with this review Bill. Every Audiophile owes it to himself to somehow audition this amplifier.

I'm reminded of Peter Moncrief's commentary years ago regarding the magical aynergy of the Futterman OTL-3 and Quad marriage. A rare and singular sound all should experience at least once. And so it is with these monoblocks, my final amplifier purchase.
Chambersburg, PA

Like the way you write and find your comments fun, on target and colorful. It's hard to put into words all these amps do so very well. As you say "All the audiophile requisites are there and become secondary" So very true!! They are state of the art in all those Audiophile ways, but there is more - much more that must be experienced.

My Samsons have opened up and "relaxed" more with burn-in time. What I mean by relaxed more is the music flows with even more grace and fluidity - if that is a good word?

Hope more can know and enjoy what we have found in this wonderful amps!
Congratulations on your purchase Dave. Glad to hear you are happy with the Samson's and TRL sound.

The low level listening aspect of the TRL sound is truly amazing. I found myself in the same situation as you, but instead of a wife it was neighbors who could very easily hear music through the walls of the apartment, even at less than modest volume levels. TRL solved that problem for me.
Bill and Tony,
Grace, fluidity, smoothness that is seemingly perfect in its creaminess.

Vocals rendered with spatial character so tangible it's like a sonic MRI scan of the physiological structures that conspire to produce the net result. The sensing of the chest, larnyx, face, body -- sometimes to the extent that the vocalist is physically rendered almost to the waist.

Dick Olsher described this in his Leslie test commentaries.
Never heard until now.

I know the gushing verges on excess, but I've yet to find a flaw.
What technology do these amps employ? Bipolar transistor, mosfet? Does anyone know what if anything makes them unique?
It utilizes bipolar transistors as output devices with a regulated power supply.
Hi Bill,

Just curious of the number of hours the break in process took for your Samsons.

Are they still changing, or have they finally settled in?

Mine took some 400 hours and are now constant in sound. No longer changing. I keep them on 24/7 as they dead quiet and always cool to the touch.

I've had mine for four days and have about eighty hours on them. There is no doubt that they have already changed a good bit--the bass is getting deeper and tighter, the mid range more full bodied and the highs more extended. Already, the amps are incredibly detailed and dynamic. After ONE day, my wife, who has never commented on any change I've ever made in my system (and there have been many more than I care to admit to), came in when I was listening to Alison Krauss and remarked that the system was sounding "really beautiful." At that time, they had all of twenty hours on them!

It will be fun to see where they go from here. As Bill and others have said, these are something special.

Please update me on the amps. Also, what speakers and you using with the amps?




Sorry, somehow I missed your question. I have Piega P10s. I now have probably 450-500 hours on the Samsons, and they have reached another level just in the past twenty or so hours. Paul says they will improve even more at 750 hours or so, which really is hard to imagine.

I don't know what I can add to the comments you guys have already made about these incredible amps, but I will say that not only have I never had sound like this in my system, I have never even imagined I could have sound like this. It's as if I have suddenly been give pristine master tapes of every recording in my collection. I sit and listen in awe to recordings I have known and loved for thirty years and just marvel at how they have been transformed with the Samsons in the system. I am up way too late every night listening to music, which is the best recommendation I can give.

I am afraid I will end up resorting to cliches in attempting to describe the sound, but I am especially blown away by the soundstaging, detail retrieval, and texture I am hearing in the music now. There is layering and dimension in the musical presentation that I never thought would be possible without very expensive tube amps. I feel literally enveloped in sound in a way I have never before experienced. It is truly magical.

Anyone who lives anywhere near western North Carolina is more than welcome to come by and hear them. I am well aware that the evangelical commentary by those of us who have these amps must seem a bit much to some readers, but what can I say, these are the real deal. I have exactly the sound I have always wanted in my system. What else can I say?

Well said Waltersalas!

My non-aphile friends all hear and comment (un-aided) how the music seems to have all these layers to it.

Have fun.

Grannyring: Have your Boleros broken in yet? Do you leave your Samsons on 24/7?
Boleros have broken in and I have happy ears! Goodness my music sounds so good! The Samson amps have stayed on 24/7 from the day I got them until last week.

I turned them off overnight and then turned them back on the next day and let them warm up for couple of hours before listening. I did this as I have heard this is a good idea to do with some amps. Something about letting the caps and components totally discharge once in a blue moon etc...

I was not prepared for the nice improvement I noticed. Stage size was even larger, greater sense of ease and absolute control was further improved. Music was even more inviting and beautiful.

I know it sounds crazy, but these improvements did happen. Like to know more about why, but for now I plan to turn off the amps for full discharge and recharge every month or two.

You're not crazy, Bill. Turning off the amps overnight every now and then really does make a difference. "Greater sense of ease" is an accurate description. The stage has tighter focus and image depth layering becomes more evident. It just sounds more like real music, which is what we are after.

This may benefit many here, regardless of the components in their system. It's worth trying, right?
I agree 100%. All of us should try this if we are the type that leave their systems on all the time. I am that type.


Since my TRL Samsons are a one off custom, built in a chassis that is roughly 12 inches wide, 12 inches tall and 30 inches in length, I wonder if using 2 of the Star Sound SP-004 Sistrum Platforms, side by side, would be the route to go? I see them using this example on their web site for a home theatre center channel speaker.

Any thoughts?
Wow, your amps are huge!

Yes that would work, but thin one SP1 under each amp would be better - just center it underneath.

One additional tweek you must try with the Sistrum stands.

Place about 3 pounds on clean sand in a large zip lock bag. The ones that are about 11X11 or so. Place it on top, centered, on your Samson amps. Play with 2-4 pounds and then listen.

I had my wife make nice black pillow cases to place the bags into and they look great. I will let you play without me saying anymore here.
We've done the sand bag trick in the past on top of recorders during a few of Paul's DSD recordings. You know, I haven't tried them on the Samson amp chassis yet. Great idea, Bill and thanks!
Nice reviews.I've been wondering if anyone who has heard the sampsons has heard the spectron musicians as well.
Sorry to say I have not. With as many amps as I have owned and heard I just have never tried a Spectron.
I actually thought about the Spectron before ultimately deciding on the Samsons. Once I got the Samsons, I stopped thinking about the Spectron---or any other amp. They continue to amaze me every day.
Thanks for the replies.I actually have one spectron but the cost of going monos is a bit price inhibitive for me.I thought perhaps i could sell the spectron then top up for the samsons
My D-225 amp was an odd size. About 22" wide x 20" deep x 2" high. I used the Sistrum SP-101 under it and it worked just fine. Also tried sand filled bags, lead shot filled bags, and VPI Bricks on top of the amps. I preferred the VPI Bricks. As an interface between the VPI Brick and the top plate of the amp I used 40 durometer rubber squares that were about 1/8' thick.
What amp stands are you using, Waltersalas?

Hi Brian,
I have them in a rack, sitting on maple butcher blocks. The blocks made a nice difference.
I've used maple blocks in the past, nothing wrong with them. I think that I'll need to give the Sistrum platforms a try someday soon.
Recently I took delivery on a new pair of TRL Samsons and I have to agree with this review 100%. This purchase was solely based on research with NO pre-purchase auditions so really didn't know what to expect and was kind of nervous. To my surprise, the amps exceeded my expectations and sounds FABULOUS. It doesn't sound like tube or SS but just music!

The Samsons replaced (not due to sonics) a pair of SF Power 3SE+ that I liked very very much. My biggest fear going from tubes to SS is losing the tube magic and surprisingly I don't miss anything with the Samsons.

The amps are on 24/7 and not fully broken in yet. Everyday I hear improvements which is very exciting and something to look forward to in the coming weeks.

I had mine built with the new 1" face plate chassis, XLR input option and dual spkr binding post. Paul is very accommodating and a WONDERFUL person to deal with. I truly enjoy our exchanges very much.

I like to thank Topsel, Clio09, Gallant_diva, Tfl303 ... for sharing their TRL experiences with me that ultimately helped me pulling the trigger.

I also like to thank, the last and definitely not the least is Albert Gore for inventing the internet where I can discover these hidden gems.
Very good! Great to see others enjoying the Samson amps! I am still loving mine as they are now driving Soundlab speakers.

What speakers are you using? Dude preamp?
I'm using EW Andra IIs. It's a very current hungry speaker and works well with the Samsons. Biggest improvements over the tube amp are dynamics and bass. Holst The Planets, Sonny Rollins, Art Pepper ... never sounded so good. You can feel the dynamic swings ... now I understand why HP uses The Planets to test dynamics of a system.

The Samsons should be a perfect match for your Soundlabs. I want to audition the KingSound King II when it's release this fall.

I took delivery on a new VAC Sig MKIIa preamp 3 month ago. It's the best preamp I've heard and CANNOT imagine Dude is superior. Kevin Hayes is another genius. Because of the Samson, I'll probably order a Dude to compare in the future. Paul predicts I will order one :-)

Here is the rest of my system:

MW Transporter
MW Oppo BDP83
All ASI Liveline cables
Everything is plugged into an EquiTech 2Q.

I have 2 20amps dedicated outlets for my system. When I get the 12' PCs from Paul, I'll compare Samson to 2Q and direct to the wall. I predict it will sound better with the 2Q ... it doesn't limit current.

For the 1st time I'm completely happy with my system. It's time to relax and just enjoy the music.
You have a great system! Yes, his powercords are great on the amps.

I bet those speakers are a great match with the Samsons.

Thanks! Samson is the final piece to the puzzle.

Because of the Samsons, I plan to get a Dude and TRL digital mod for a shootout.
Great to hear that King, congrats and can't wait till you get the Dude ;)
Samsons are amazing, that's true, and Paul is a great guy to deal with.
Happy listening days!!!!!!
Im starting to save up for a pair of Samsons!From what ive read, I think they should be a good match with my Supratek Chardonnay and Harmonic Precision Caravelles.Bill,Thanks for the review!Ray

Did you get rid of your Samsung monoblocks and gotten yourself Atlas tube amp? Reasons? Regards
Kot, I owned Soundlab speakers and simply needed more power to drive them as I wanted. That is the only reason I sold them. I miss them and bet they would sound great on my Nola speakers. Right now I am very happy with the Atlas however. I still consider them the best sounding solid state amps I have owned. I do like tubes and thus far the Atlas is working well in my current set up.
Samsung...that's funny!

The Samsons were not up to the task driving SoundLabs?! Weird, given their high current, high voltage reserves....Did they "spit" sibilants at high volume I wonder?
I ve heard the Atlas amps on couple of occasions and found them just ok, a typical, politically correct audiophile sound, especially compared to the Tube Research Lab Tube mono 400s...Granted, those are much more money these days, but if we are talking absolutes, have you listened to the lesser tube Tube R. Labs models? Regards....
The Samson amps always sounded better on any box speaker I tried compared to other SS amps. The problem was only with the Soundlab's. I would not even call it a problem. They sounded quite good. I went to a 600 watt per channel amp that was load invarient and did not care about the speaker's very high 40-50 ohm impedance in the bass region.

I have never had a chance to compare the Atlas to the Samsons. My Atlas is the stereo amp with wonderful Hydron Red base NOS's that really improved the sound. That combined with the TRL power cord on my Atlas makes for a great sounding amp on my speakers. It is always about total system synergy.

I wish I owned the Samson's now as I bet they would sound great with my Nola speakers. The Samson's were simply glorious on my Silverline Bolero speakers as well as my Dali Grand speakers.

Soundlab speakers are quite a different animal with impedance swings from 2-50 ohms. Many SS amps do not like to see high impedances like 40-50 ohms in the bass area and can begin to sound tipped up in the highs as the volume is turned way up. This is why 600 watts per side worked better for me.
Forgot to mention most SS amps only put out a very small fraction of their rated power into impedances as high as 50 ohms.
Well are not the OTL's best suited for the Sound Labs? I remember roughly 15 years there was a company Sans Pereil which produced highly musical amps... I used to own Acoustat Spectra hybrids and on one occasion drove them with a solid state amp with no problems..Granted I agree that Sound Labs present a unique ascending load....
I owned the Atmasphere MA1's and they just did not have enough power and would clip at 85 - 87 db in the highs. Nice sounding until that point but too limited in volume on this speaker for my room.