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Compress and Boost Your Sound With Weight, Harmonics & Character








The Weight Tank Compressor will put a stamp on any material run through its circuitry. The smooth and euphonic sound of soft-knee vari-mu compression paired with thick, distinct and colorful harmonic saturation makes the Weight Tank Compressor very unique.



Three all-steel transformers deliver big, thick, colored results


Audio passes through two vacuum tubes for smooth warmth 


Backlit meter displays gain reduction



Variable attack & release timing allows for great flexibility


When run in “Round” mode, a smooth, sweet and pure tone will result. If switched to “Drive” mode,  an enhanced harmonic structure and overall driven tone will result.


WT-COMP Tape Op Review

"The WT-COMP does exactly what it is supposed to do, and would be a superb addition to tracking or mixing setups in need to good value, characterful hardware options."


WT-COMP Tape Op Review

“The Weight Tank has tapped a niche with its original design and price point, operation is simple, and the layout is clean. It's solidly built and can handle lots of different source material.”

average rating is 5 out of 5

May 21, 2023

CwC Studio

Sweet euphonic bliss to deep growl

Describing the WT-Comp is difficult as it is something you feel as much as you hear. I bought this mainly for processing Di bass which it excels at. The WT-Comp adds a texture and fullness that has me no longer reaching for EQ. Density is a word that comes to mind. And in drive mode, you can take a polite Precision Bass and turn it into a growling monster. But the WT-Comp uses are far broader. It can be aggressive or very smooth and controlled. On round settings, I've been able to get vocals to become richer and more 3D with beautiful fidelity. And the compression action is incredible - I aim for vocals to be compressed enough where they sit in front of the mix and feel like they're on the verge of getting out of control but never do. Something that popular Opto compressors just can't do. The WT-Comp has made it easy to tread that fine line. Try running analog synths through it and slam it in drive mode. There's nothing else out there that sounds like it. Kudos to Locomotive!

average rating is 5 out of 5

January 11, 2021

Detective 47

Weight Tank Compression *********

I was doing a lot of searching to find a pair compressors to use for a group bus to handle guitars and other acoustic instruments. I discovered Locomotive Audio and after doing a deep dive on the Weight Tank compressors I decided to go with them.
Its been about two months now and I have say they are incredible. I use them for all sorts of different purposes. For mixing, I route all my guitars to them and sometimes throw in other instruments as well. I'll often do parallel vocal prints with them as well. They have become the go to for tracking any acoustic instrument. Another bonus, is that they sound great on synths. I have an old Roland VP330 and OB8 and I used to run them through distressors but since I've had the WT's I've been using them exclusively. They add a sound to these instruments that is really amazing and I'm also able to get little more gain without having any additional noise which was sometimes a challenge in the past. The drive mode is great on certain application and adds a nice saturation.
For the price of these units, it really is a killer deal. The owner of the company Eric was also kind enough to talk to me and answer a bunch of questions I had about the units.
In conclusion. Great service, excellent product!
Looking forward to getting a 14 B soon!

average rating is 5 out of 5

September 28, 2020

Lucas O

Exceeded my expectations. Now I want 2.

My first impression upon unboxing was that this unit is very well built. The WT-COMP is a tank. No dainty aluminum box or flimsy knobs/switches. All of the tactile controls feel pro. The physical resistance on all 4 knobs is consistent. I know some people might not care about these things, but at that price point, I really wasn’t expecting much. It speaks a lot to Eric's professionalism. And the custom GR meter is beautiful.

The unit sounds excellent! I love the harmonic character it brings to just about anything I send through it. My go-to on electric bass. Even with subtle GR, it does something really pleasant to the tone. Instant charisma on vocals. GREAT for giving rock vocals some attitude. Very cool on drum overhead, both subtly tapping it, and also slamming it in parallel.

The Round/Drive modes are the icing on the cake. I find this feature extremely useful. In a thick mixing context, where EQ and compression get a sound 90% there, I found myself closing my eyes and switching between both modes on the WT-COMP. I was surprised how often "Drive" would make an element instantly sit better in the mix and play more nicely with everything else.

I wanted to share my experience because I rarely get knocked out by new gear. This piece seems like a modern classic. It’s a great tool for anyone working in the box that wants to add legit color to their mixes. And for the price point, it’s a no-brainer. I’m already saving up for my next WT-COMP!

average rating is 5 out of 5

August 16, 2020

Mats Sweden

Highly recommended!

I'm happy to admit that I'm a fan of Eric products. WT-COMP is very nice and colors in a wonderful way. I use Locomotive 286A pre in chain with WT-COMP in tracking. In recent years, I have worked more in the old school with pre, compressor and EQ when I record and then work more "in the box" when I mix. This chain is definitely one of my favorites in these contexts - and I have a lot to compare with. WT-COMP works in all contexts from acoustic to electrical instruments! The acoustic recordings are usually made with a Swedish-made microphone - Thuresson CM402. In this way, I merge two giants in product development - Eric Strouth USA and Jörgen Thuresson Sweden WT-COMP on buses or master channel? Absolutely YES!
Highly recommended!

average rating is 5 out of 5

August 3, 2020

Joey M

Vari-Mu for the Soul

My quest for audio excellence started as soon as I got into the audio industry, but felt that plugins would get the job done. I quickly found that my mixes and music in general were lackluster and did not have the full sound. I was introduced to Locomotive Audio at NAMM in Anaheim a few years ago next to the Neumann booth. I quickly fell in love Locomotive Audio and got to know Eric, the owner, and what his story was. I purchased some gear soon after and recently picked up the WT-Comp to add to my hybrid mixing chain.

The WT-Comp lives on vocals in the mix. I don't necessarily like to track with compression so I mix with it. I HIGHLY recommend the "Drive" option on vocals as it gives the voice something special that only real analog gear can do. Depending on how you set Attack and Release, you can achieve a super smooth vocal that people will lust for that sounds HUGE. I like to give nicknames to my gear and the WT-Comp goes simply by, "The Tank." Eric's build EXUDES vibe so the WT-Comp fits perfectly in our collection.

The Locomotive/Weight Tank options are excellently priced and allow any end user to get that "radio sound" without breaking the bank. Eric is extremely easy to work with and is very passionate about his products. You can tell this by the attention to detail in his builds. If you are questioning whether or not to purchase from Locomotive and/or Weight Tank, let this serve as a sign that you need not look any further.

average rating is 5 out of 5

August 3, 2020

Jorge O

Fantastic sound, killer on bass!

I was looking to add a Vari Mu compressor to my studio, mostly with the idea of having a go-to piece for bass mixing. My dealer recommended the Weight Tank over a revered unit that costs 3 times as much. Their exact words were "it’ll be probably the best thing you’ve spent that money on in ages" (I still have that email saved).

As expected, it kills on bass, electric or upright! In fact, using it on the upright felt almost like cheating. I could dial the exact amount of finger attack noise that I wanted and the compression showed no artifacts.

It's parked on by bass chain (usually I track with an 1176 and mix with the WT) but I've used it for vocals and it was great too. I remember it worked really well on a mandolin track too.

I haven't found use for the drive setting but I'm glad it's there if I need it. Oh, and the unit looks fantastic. Just get one! Or two!

average rating is 5 out of 5

August 2, 2020


Personality and Vibe

This is a really great unit! Don't let the price fool you. Eric builds high quality, awesome sounding units, priced well below anything out there, especially the cookie cutter junk. I am big fan of Vari-Mu units. I own a bunch, but this thing stands out. Plus it has that "drive" feature which is way cool. The WT-Comp has personality and vibe which is what I look for. And I love doing business with a small American company that celebrates passion and quality.

average rating is 5 out of 5

August 2, 2020


I freaking LOVE Vari-Mu's!!!!

When it comes to compression that leaves a sonic imprint, I love Vari Mu compressors. It seems that so many of the revered classics are of Vari Mu design, and the WT-Comp stands right up with all of them. It does it's "own thang", but it definitely carries with it the ghosts of so many of the greats that came before. It's got it's own unique personality though and IMO it has it's own special place in the compressor stable with the greats. Mine get used constantly, and for some reason, it really tends to get used here on Electric Guitars. Heavenly, swampy goo that will help cut and glue like crazy - with a killer ORGANIC vibe. Conversely, I really dig it on synths as well. Go figure. It's not as simple as a 2a (Opto) but there are not tooo many controls either - so recall is a breeze. It has just the right balance of control and quick intuitive simplicity!! Round and Drive add a huge overall impact to the usefulness for me - LOVE that inclusion! And having attack and release make it much more flexible than an Opto. Also, something that I truly appreciate - the ergonomics are so simple to read from across the room - again making recall easy. So for me, it's definitely a keeper. Enough so that I ordered 2. And I keep thinking about 3 or 4. LOL. Eric is a tube guru, and at this point, I'd pretty much trust his WT / Locomotive products without even a precursory listen if the product fits my needs. Now it EQ time yet?? :)

average rating is 5 out of 5

July 31, 2020

Justin H

Killer tone, action and great price point

I'm not big on writing, I will say my actions speak louder than my words.
I own four of Eric's wonderful pieces of audio black arts. A prototype of WT-comp,
two production units and the Locomotive 14b. All hold there own against the greats
STA-level, Altec 436C, manley vari mu and a fairchild clone, Oh and the CBS RIIZ 6386 comp. Those are my personal units to compare with. Anyway the basic set of controls allow you to just dial in by ear rather than looking at a dozen knobs, this is my preferred method in the day and age of everyone staring at a computer monitor when making musical decisions. I have achieved great results on vocal tracking, acoustic guitar and drum overheads, my aesthetic is more toward 60s-70s records and these units help me get there. His builds are tops and he is a great guy if you ever need his assistance. can't say enough good and never had a negative issue.

average rating is 5 out of 5

July 31, 2020

James S.

Everything I Ever Wanted in a Vari-Mu

In April 2018 I bought a matched pair of first generation WT-Comp.

First off…
I LOVE these things. They feel great on 2 buss, and I’ve never had a compressor that I could squish a mix so much with and still not feel squished. I adore them on vocals. Smooth. Make the nastiness vanish kinda smooth. OK, that might be exaggeration, but it feels like it’s true. Clean guitar instantly doesn’t feel boring anymore. Bass guitar feels rounder yet controlled and punchy. So I’m really happy.

Might be the single best “New” investment I’ve ever made in Audio gear. The cost was well below what I'd planned to spend, and it still delivers all the character and control that I was looking for. On top of all that, Eric's customer service has been second to none. Every question I've had he's answered quickly and thoroughly, setting the standard that I compare EVERY other gear manufacturer to. I couldn't be happier.



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