Review: Tube Research Labs Dude Tube preamp


Category: Preamps

This review is on the Dude tube preamp made by Paul and Brian Weitzel of Tube Research Labs (TRL). I purchased this preamp some 7 months ago direct from TRL which is how they market and sell them. The price is $3500. The unit has 5 tubes total with one 6sn7 tube per channel.

I am not a technical person and can only comment that the unit is very heavy, all point to point wired and contains a forest of caps the size of Red Bull and Coke cans!

The Dude also benefits from TRL’s newly designed power supply which is something very special indeed. It comes with two sets of outputs and three inputs – all RCA. I think Paul can work out XLR’s if you desire, but you would have to ask him. My unit has special wooden knobs which I prefer over his high quality gold ones.

The unit is turned on by a breaker switch on the back on the unit. The Dude does not incorporate any fuses, simply the breaker, for improved sound. The chassis is well built and solid in terms of fit and finish. While it is not eye candy, the Dude offers a simple attractiveness.

I must have over 700 hours on my unit by now and it is fully burned it. I have found this preamp responds very well to tube rolling. This review is based on the use of RCA 6sn7 GT’s ,VT231 with smoked glass. I picked up 6 of these for $130 on Ebay and just love them in the Dude. Paul likes Raytheon NOS’s, but I have not tried them as yet.

I like female vocals, Christian contemporary, jazz, piano and acoustic guitar instrumentals as well as some small ensemble Classical. You can also read my review of the TRL Samson amps for more information of my musical tastes.

As you have noticed I have owned and heard many great preamps over the years. The Dude has far outclassed each of them in virtually every important performance area. I particularly liked the Audio Horizons and Tube Distinctions preamps on my list. The Dude simply recreates real music in my home well beyond these other fine units.

The level of transparency is utterly shocking. Details and musical lines previously hidden now come alive and my music sounds brand new to me. I was amazed at all the instruments and notes I was missing in my recordings. What a revelation and joy to me as one into this hobby for 30 years.

Right now I am listening to solo acoustic guitar by Phil Keaggy and am consistently astounded with the additional pic, string and guitar body sounds completely hidden before. The sting plucks are so much more distinctive with every molecule of nuance presented to my senses. This is true at even the lowest of volumes on my system. Magic my friends and I mean magic!

I have never known any preamp to dig as deep, taunt and powerful in the bass region as the Dude. Bass has incredible impact, drive and articulation. Easily the best bass I have yet to encounter in a preamp. This tube preamp will shatter your preconceptions of tube preamp bass performance. Bass is no longer this vague sort of deep running tone, but rather a distinct and articulate portion of the whole performance.

Tonality is so beautiful and right. Not a hint of listener fatigue to be found. The massive amount of detail is delivered with exquisite beauty, body and soul. Don’t we all want that? The Dude does both in a way I felt was not even attainable. Tonality is vitally important to me. Voices have weight when they should. Like the guitar work nuances mentioned above the human voice is rendered absolutely and completely naked before you. You will hear aspects of your favorite vocalist you have never heard before. More air, more texture, more nuance, more personality – just amazing.

The Dude sets the stage big, wide and deep. First time I have heard stage depth so profoundly obvious. I now get a sense of what some reviewers mean by 3D! Life sized performance is a consistent attribute of the music flowing from this preamp.

I like to listen to very loud music at times. I like the live scale it gives the recording. The Dude is always in control and supremely poised. Nothing, no part of the audio spectrum is ever out of balance or forced. I hear a new standard of performance in terms of effortless, uncompressed music.

My system seems to have infinite room filling abilities. This is very, very important to me. Even at very loud settings music must flow not attack! The Dude is a complete gentleman in this regard.

Highs seem to have no ceiling or cap as they extend smoothly and without any hint of hardness. I am very sensitive to bright or hard highs and will quickly box up a unit if I hear a trace of it. Yikes! The Dude is a smooth operator and does so without robbing music of the precious detail and air we desire.

Well, I could go on much longer as the Dude is a revelation to me. It is the heart and soul of my current system and really makes everything sound so real and right.

I hope my words were able to convey what I experience with The Dude.

Have fun!



Associated gear
Please see my member system.

PBN Montana EPX custom speakers
TRL Modified Sony CD player/battery
TRL Samson amps
Audio Horizons cable
TRL Cables
Star Sound Sistrum stands
Echo Buster room treatments
SVS PB 12 Plus/2

Similar products
I have owned or had these preamps in my home system.

Audio Horizons TP2.1 fully loaded
Joule LA100 MKIII
Conrad Johnson LS16 V2
Thor 1000 MK2
Tom Evans Vibe
Supratek Cortese
Supratek Syrah
Audio Note m5
Wavac PR-X1
Rowland Concerto
Cary SLP98
Aesthetix Calypso
Tube Distinctions SoulMate
Placette passive
Wright Sound WLA 12A
Aloia 11.01
Belles 21A
Rogue 99
128x128grannyring

Nice account and easy read. Thanks. nice rig as well.

.... better than all those in the list top to bottom, or in just some respects?

Several of those you have on your list I have either heard or owned, and it is sufficiently interesting enough to me to ask this.

Or do you suppose perhaps that now, as your system's power train is all of one ilk, inherent synergy is responsible?

Also, more pointedly, how would you recall the Thor line stage stacking up with the TRL pre.? You didn't have the Thor with the TRL amps, though, did you?

Very interested, thanks much.
Great questions and important. I will try and answer as well as I can. Thanks for your kind comments.

I have owned or had all of those preamps in my home system over the past 5-7 years. I was lucky enough to sell many of these preamps for audio friends of mine and thus had them in my system for several weeks at minimum.

Sometimes I would choose to buy one and keep it. I have only had 2 sets of speakers over the years in my main system. I have however changed out wire and electronics over the years so my comparisons should be understood in that light.

I was able to compare the best sounding preamps (in my opinion) on a pretty consistent package of gear. The Audio Horizons beat out the Thor , CJ, Suptratek's and Tube Distinctions which were the best of the list for me. I did compare these with pretty much the same gear. The Audio Horizons won out.

I then compared the AH preamp & Canary CA339 mono tube amps to a TRL ST225 integrated amp. The TRL surpassed that wonderful combo and started my interest in TRL as you might imagine.

I tried the AH pre with the integrated TRL amp and liked the TRL Int amp all by itself better. I sold the AH pre at this point. I then decided to try the TRL Dude preamp with the integraded and was instantly amazed. The Dude improved my system to such a degree it was shocking to me.

It was not a matter of matching or synergy alone mind you as the TRL integrated amp was made to run best with a high quality passive preamp section.

With the Dude everything I mentioned in my review came out of my speakers. So for me the Dude was the MAN!

As good as the Audio Horizons preamp is the Dude simply made it sound like good hifi. Please keep in mind the AH preamp was clearly better then those other top preamp contenders on my list as just explained. (At least in my home and in my system)

The Thor was very lively and had great pace and drive. The Dude bettered the Thor in even these strong suit areas of the Thor. The Dude has greatly improved bass, more natural tonality and really overshadows the Thor in resolution of detail and intimacy. The Dude throws a larger stage with more depth and plays much louder without the tendency of of sounding "loud".

The Thor is a nice/great buy today used at prices of under $2000. Very good deal indeed. If one has the money $3500 buys you so much more with the Dude. Not a small difference mind you, but rather one of significant magnitude.

When I purchased the TRL Samson amps I knew I was at the end of the road with amplifiers. Yes, I think they work great together. The Samson amps offer ultra high transparency and the Dude matches it. But the important point here is this; it match it with beauty and graceful tonality. I don't like transparency if it comes at the expense of texture, body and grace. The Dude is the perfect mate.

The Dude is the ideal center piece of any true high end system as it expresses music as it is with life, energy and fidelity to the instrument recorded.

Hope this helps you.
I am not sure. You should ask Paul. Paul has told me he is not a big fan of adding remotes as he feels they degrade the sound and add noise.

I see many great preamps with remote so I guess reasonable people can have a different opinion on that whole question.
It just may add cost and that may be the real objection.

You can certainly ask him.
Dude Grannyring,

That's alot of pre amps you have heard/owned.

A big tip for you. Get the SP-101 and PUT IT ON THE FLOOR, and set the Dude on it. What three days of listening and report back. If not the SP-101, then take the SP-1 and put it on the floor (earth) and report back. The Dude will be an even bigger Dude.

Sistrum stands work best on top of each other or on the floor. It looks like you have it on some other stand?