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

Showing 50 responses by agear

Gallant_diva, well said. Some guys with SOTA gear suffer from price bias and think that the Dude's too cheap to outperform things costing 3x the price. There is only one way to find out....
I tried to source good Raytheons on Ebay and was not successful, so I have not heard what those tubes can truly do.

I am using the stagger plate RCAs and those are sweet.

Some folks have recently tried the Russian NOS tubes to good effect. A lot of folks also clammer for the red label RCAs, but I have heard they are uber pricey.
Bill, my Dude is still sounding phenomenal. I will be writing a review soon.
That's kool Tony. The Joule Electra was/is a nice pre-amp. I have also heard that Rowland pre when I was still in Minnesota through some Eggleston Andra IIs. Again, things sounded good. I am looking forward to your perceptions of the Dude since you are a seasoned and fairly analytical phile.
I am curious too.....

Gallant_diva, where are things? You have had the Dude for a few months.

I know Pat/Rx8man has not received his Dude yet. He does have a TRL passive which has surprised him....
I think there are many variables at play in reviews, and there is value in both initial impressions and long-term, systematic analysis. I also think there is value in blinded listening sessions with multiple listeners to remove bias. Most people are scared of that...of not being able to recognize your own piece of gear, etc. There is also something to be said for involving non-audiophile involvement whose observations can sometimes be shocking and revealing. In summary, the more information, the better. Gallant, you have a computer, engineering background. I think you would agree with all this....
Gallant, thanks for the thoughtful review. The Dude's presentation changes fairly markedly with tube rolling, so that is one place to fiddle. You may also want to find cables that are less sensitive to length. Dale Pitcher's are generally not and might me worth investigating. Some philes do not believe in cables, but I have noted profound differences after switching to Dale's cables. Keep us posted.
I also agree with your comments about Paul. I have observed that guys who inhabit a creative sphere where designs literally appear in their minds (or are given to them....it depends on what you believe) are not the best businessmen. Audio mysticism and keeping your eyes on $ and time do not seem to coexist easily. Dale Pitcher from Intuitive Design is the same way. My entire system has been built by audio mystics. It requires patience and endurance like any good relationship (and it is just that,... a relationship), but it is so worth it in a hobby that creates many fleeting relationships.
Gallant, what isolation devices are you using? What is the Dude sitting on? Also, what power cord is feeding the Dude?
Gallant, those are good observations. Those monster caps seem to take time to warm up. I have experienced the same phenomenon with my intuitive design speakers. Furthermore, the bass is very "present" and tuneful without being bloated.
Bill, no surprises with that shootout. Most Dude owners sound like shills due to our level of enthusiasm. A friend of mine did a shootout with his older generation trl pre-amp and a concert fidelity (20K) pre-amp that many consider SOTA, and it was no contest. The Dude abides....
Waiting for the Marconis? Sounds like you and Bill spoke. Good deal. Enjoy....
Nice system Bugred. 99.9% of people who buy Dudes keep them. I know of one owner who had a noise issue (that turned out to be a capacitor gone bad), but he had that fixed and is uber happy....

Where do you live? If you are in Charlotte, NC, you are welcome to hear my rig...
Tvad, you stated: "Don't know the goal of the Dude, but if it's other than absolute transparency (and from owner's comments it seems that this is true), then a comparison would be apples to oranges..."

I don't think that statement holds water. I would presume that most pre-amp designers have the same goal in mind: an accurate auditory illusion. Transparency is only one attribute in a long list. From my conversations with Paul Weitzel and in my own experience of the Dude, it is fast and dynamic with no hint of compression (high bandwidth creature) but at the same time capturing the subtle nuances of music such as timbre.

"sounds like a comparison would be useful for some listeners, although the price points are so far apart I am dubious that most potential Dude buyers would be seriously considering the VRE-1 as an option...."

That is also untrue. There are Dude owners with 100K+ tube amps in the chain, so $ is not always relevant.

I think some sort of shootout in the greater Los Angeles area would be enjoyable and educational. I know there are Dude owners in the area who would play ball.

Tvad, I noticed that you recently sold an Audio Note pre-amp. Why the change? I also remember you owning top of the line Atma-sphere in the past. How may pre-amps have you been through in the last five years and what is missing in the units you have owned thus far?
Tvad, that's fair. Fiddling/experimenting is part of the hobby and I respect those who do fearlessly without concerns regarding the outcome. There is a constant tension between a desire to get off the merry-go-round and fiddling. I am currently off and enjoying myself.
Bugredmachine, congrats. I have the humble (some would call it "rustic") gun metal grey. It looks very kool...in a vintage sort of way...like it was extracted from a WWII sub. My wife likes how it looks and she is a fashionista and a snob. I would do blue. That would be awesome. Welcome aboard.
The 12SX7s will soon be pricey because we are gassing about them online. I think we need to restrict tube data to personal communications so prices don't go through the roof. That is what happened with the 6s in the last year. Why make it happen with the 12s....
Bug, the output tubes live right behind the face panel when the top is popped. Check in with Brian and Paul when you ready to do the deed. Make sure that the Dude has been unplugged and off for some time. Those monster caps hold a charge for some time and can be potentially dangerous if touched inadvertently (at least that's my understanding....)
Tony, the Weitzels had concerns about the 12s going the way of the 6s and thus my impetus for relaying the info....

In the Dude output stage, the 12 is essentially a direct replacement. A minor mod is all this us required to accept the new voltage. According to the Weitzels, it is a 5 minute job for someone with technical know-how....
"If a minor mod is required to accept the new voltage, no matter how long it takes to make the change, it is not essentially a direct replacement. A direct replacement would be a simple tube swap IMO."

So you are arguing semantics? Me no understand the point of that...

"We're talking about a tube for God's sake. This country was built on an economic system where prices of products are based on supply and demand. If people are worried about the price going up they should buy all they can when the price is low. Ever heard of the concept buy low, sell high. It's capitalism at its best."

a philosophical non sequitar.

"[SIDE NOTE: If I were a manufacturer building equipment that uses these tubes I'd be stockpiling them. That way they could look out for the best interests of their customers and protect them from the evil people who are going to inflate the prices to make huge profits when demand rises. If the manufacturer offers their customers the tubes on the cheap its possible they could help in the effort to keep the prices reasonable across the board]."

TRL has been generous enough to offer NOS 6SN7s with their Dudes. Their personal "stockpile" of tubes is diminishing and they are thus trying to replenish it. They have been disheartened by several recent trips to see old friends in the pacific northwest who had a bunch of these tubes and have now been picked clean by tube sellers.

"I thought these forums were supposed to be about sharing information and experiences. Now we're talking about keeping things hush because we have concerns the price might go up if too many people know about it. Sounds like some type of exclusivity to me."

True enough, but what is the relevance to you? You don't own one, but I think you need one. It has been clinically proven to lower blood pressure. Owning the Dude has real health benefits....

"I know a guy with a boat load of these tubes. He's going to be all smiles when he learns how valuable they're going to be."

My point exactly....

Bug, try the TRL cords. They are relatively affordable and very good. The Dude, like most TRL gear, is less cord sensitive than other equipment I have owned presumably due to the quality of the power supply....
That is kool Gallant. I am still searching for the optimal tube. The Marconis are good but not perfect. Dale Pitcher at Intuitive Design has some cryo'd tubes that I am going to try. When I owned a Granite Audio 657, I used his treated 6922s and they were significantly better than anything else I tried....
Interesting tube King, although I would like to know how they were able to measure reduced "electron swirl" that resulted from their proprietary carbon coating. Are they really $200 each?
King, question: when tube rolling the Transporter, was this eval done with the LSA in the chair or your tubed pre-amp?
Bug, I saw a photographic preview of your pre-amp minus only the top, and it looks spectacular. Bravo.

As for amps, I would snag a pair of Samsons. The synergy is glorious, and the two become more than the sum of their parts. Bill/Grannyring can attest to this phenomenon. Prior to owning the Samsons, I had Intuitive Design Coordinate monoblocks. Many philes consider Dale's SS creations some of the best in the world (at least during his Essence days). The Coordinate amps did some things better, but in terms of an organic, tube-like presentation with the speed and scale of high current SS, the Samsons are very hard to beat, particularly for the price point and the presence of the Dude.
Bug, I agree. I have black and it looks fine. Discrete. Once you are awash in the sonics of it all, the last thing on your mind will be color.

What was the final price tag on your Dude with all the custom work? I presume it was not $3800 as you listed in your system link.
Sgr, why are you asking? Are you unhappy with your Ref3? What other pre-amps have you heard/demo'd and why did you choose the Ref3?
Sgr, a Dude owner named Huy (who lives in Dallas) A+B'd the Dude with the AR reference anniversary pre-amp. I will let you talk to him about his findings. I heard about them second hand and do not want to speak amiss. Paul Weitzel at TRL can give you his contact data if you so desire.
Yeah Sutts, the LL is a funny name. Interestingly, the Little Lebowski has morphed into a transformerless OTL amp. This will be a TRL first from what I understand. Should be interesting. Gary Anderson (aka Glory) will be the first recipient.
I have not. I have used both Herbie's tenderfeet on a dedicated rack as well as Equirack footers. Both are good.
Steve, I would call Paul W for more explicit details. The Dude has gone up against some top $ pre-amps and done well. You have to remember that TRL has been in business as long or longer than some of the bigger names you mentioned, and is not a johnny-come-lately outfit.

Have you compared the ref3 to the 40th anniv piece?
Bug, your Dude looks spectacular. I am generally low key about equipment aesthetics, but I did briefly covet your Dude.

Sgr, time to completion of order is variable depending entirely on whether you upgrade the faceplate, alter the color, etc. The machine and anodizer shops are the rate limiting step in the TRL equation. I got a plain jane Dude and it took a little under 2 months.
Sgr, nice room BTW. I agree with you 100%. The room is the most important component. We will be finishing our basement in the next 2-3 years, and I have a room design in mind. We are having kids soon, so soundproofing is essential.
Bug, that is awesome. You are hearing what we have all heard. I am not an aggressive evangelist by nature, but the Dude bowls you over and you cannot help but share in the sheet giddiness of it all....

The Samsons are also staggering. The synergy is to die for. It is a no brainer....

Sgr, go for it....

I too am jealous of that blue chassis.
Pat, the dual volume control is an additional option that costs $ I believe.

Tthean, I waited a month and a half. Average wait time seems to be more in the 2-3 month range. It depends on if you order specials colors, 3 inch face plate, etc. You have to remember that no printed circuit boards or pre-fabricated chassis are used here. It is an artisan piece that is point to point wired in a chassis that makes previous pieces I have owned feel like a coke can. The newer Dudes with the 3 inch face plate are weighing in at 75-80 lbs....
Hey everyone. Check out Miguel's Dude: http://cgim.audiogon.com/i/vs/i/f/1300480343.jpg

Righteous....
He loves it. Better in all areas but cannot name names out of deference....
Yeah, that is good news. I told him to fill a bomb shelter with Samson parts....
Bill, not sure about that one. My Dude lounges around on the couch in his effortless existence. He does not have to try hard like so many other pre-amps....
Johnsonwu, does that apply to Sophia? Do you want to elaborate on your experiences?