Badcat Unleash Review

Anyone who has owned a tube amp sooner or later discovers that it has a a “sweet spot” where it sounds best.  There is a range where differences in picking attack alter more than just the volume that comes out of the amp; the guitar’s tone changes as well.  Guitarists from Charlie Christian forward to the present day have used this quality to add expressiveness to their playing.  When you get to the upper range of the amp’s ability to produce more volume, the signal not only becomes more distorted, but begins to compress as well. This adds a singing quality to the sound, enabling a guitarist to emulate the long sustained tones of a horn or a string instrument.


Depending on the amp’s output power, speakers and cabinet design, each amp allows a “window” of usable amp volumes.   Below a certain volume, an amp won’t allow the guitarist to access the “touch sensitive zone”, (which actually might be desired with some styles and types of music) and eventually the amp gets to where additional signal produces more distortion than you might want.  (This does vary from guitarist to guitarist; a country player might want just a little extra “spank” to his Tele’s sound, some people can’t ever have enough distortion.)

For the big time touring guitarist playing large venues this doesn’t pose much of a problem.   What ever rig he uses  on stage, the sound engineers will find a way to feed his sound through the PA system so the audience hears pretty much what he does on stage.  The technologies used to do this are varied and beyond the scope of this review, but suffice that those of use that aren’t headliners have always had the dilemma of matching the amp to the venue.

You can use a big amp that can play loud enough to cover most any situation, and some guitarists (mostly those who have a mostly clean style) can use an amp like a Twin Reverb in any setting, (even at home) and be quite happy with it’s performance.   But some of us, who prefer the sound of a cranked amp to any sort of distortion device, find that we never get an amp such as a Super or Twin Reverb (or a Marshall Stack) to the point—in the venues we play in, (and this can include our bedroom or home studio) where we get into that touch sensitive zone.

Using a smaller amp to get into the sweet spot for solos at more reasonable volumes also means the amp might not have enough clean power to play rhythm guitar without distortion, and forces you to play all solos with a distorted tone if you want to be heard over the band.

There are devices that can help a larger amp produce distortion at lower volumes, distortion pedals and attenuators are two main choices so far.     Guitarists have also resorted to having several amps of different wattages, to cover all possible situations.  There are times when you aren’t sure of what the situation at some new venue is, so you end up bringing a lot of stuff so you’re prepared for all situations.

The Badcat Unleash is an amplifier/attenuator that can take the output of any amp between 1 and 100 watts and shift the sweet spot of that amp up or down to any point between whisper quiet and as loud as most any club level guitarist will ever need to play.  It has as a built in amplifier that will produce 100 watts of output into an 8 ohm speaker or cab.  (even more into 4 ohms, somewhere around 160 watts)

The first thing the Unleash needs to do to make all this work correctly is to fool the guitar amp into “thinking” that is is connected to an actual loudspeaker.  The reason this is important is a lot of the sound of a guitar amplifier is created by the way the amp reacts with and to the loudspeaker it’s connected to. Amps connected to a resistive load (like you find in most attenuators) sounds kind of dull and stiff.

The Unleash features (patent applied for proprietary reactive circuitry that mimics the effects of a loudspeaker on the amp.  This circuitry manages to accomplish the task with a degree of aplomb previously available only by spending considerably more cash than the  $379.00 you’ll pay for an Unleash.  This is remarkable considering that you also get a 100 watt amplifier with foot-switchable volume levels and an effects loop with the Unleash.

This performance level of just this one task is the key to why the Unleash is such a groundbreaking device.  Guitarists have been able to load a tube amp with some device that drops the signal down to a point where it can be re-amplified by another amp to whatever level is desired; but nobody has done it this well and integrated so many useful functions in one affordable, compact device.  But none of this would be nearly as cool if the device didn’t allow the sound, character, and feel of the “host amp” to shine through as well as the Unleash does.

I’ll eliminate the suspense and tell you right now that in terms of this most critical task, the quality of “transparency”, the Unleash exceeds my expectations.  Otherwise, you wouldn’t be reading this review and my Unleash would be on it’s way back to Badcat.

The rest of this post will be based on my experiences with two amp rigs.  The first one is as follows:

 Squier Vintage Modified Telecaster Deluxe
SX Sortacaster with 3 single coil pickups
Joyo Ultimate Drive pedal (in front of the amp)
ModTone Delay (effects loop)
Biyang Tri-Reverb (effects loop)
Coronado Amplification 5E3 with Jensen Tornado speaker 

This is my normal rig that I use with the band that a play with a Bass-Drums-Guitar combo with a vocalist.  I use George L’s low capacitance cables throughout, and occasionally swap in a Dan Electro Chorus or a rotation of different overdrive pedals, but for purposes of this review, those were not part of the signal chain. I purchased the Tornado speaker (with a 100 watt capacity) specifically to use with the Unleash.

If you look at the above photo, you’ll notice that the front panel has three knobs: the two on the sided are labeled CH1 and CH2 and the center one is the INPUT TRIM level.  The idea with the trim level knob is to set the input level so that it flashes when you hit peaks but doesn’t stay on the entire time.  You set the output of your amp first and then adjust the trim level accordingly.   The Unleash has to have some sort of limiter circuitry as I didn’t hear any nasty sounds if I turned the input level up so the light stayed on most of the time, but I did detect what sounded like a little compression.   I preferred the sound when the light was only flashing on peaks and found that once I got the amps levels set, I could set my guitar’s volume pot at about 2/3 and still crank it to full without causing the light to stay on all the time.   This is how I normally use the pot on the guitar to control my distortion level, so no real changes to my usual procedure were in order.

The other two knobs allow you to set two separate volume levels that you can toggle between by using the supplied foot-switch. I’ll have more to say about the usefulness of this function, later.

Before practice, I’d hooked up the Unleash at home to make sure everything worked, but didn’t have the opportunity to hear it at higher volume levels.  The one thing I did notice is that the delay and reverb effects sounded much better in the Unleash effects loop than they did in front of the amp.   The difference in clarity available by not running through the power amp and thus having distortion added to the effects, was amazing.  I have owned amps with built-in effects loops before, but the loop was always before the tube power stage and so didn’t offer the sonic advantages the Unleash’s loop provides.

At this point, it makes sense to explain that the amp that’s built into the Unleash is not designed to add it’s own sound to the mix.   It’s only function is to increase the gain of the signal without any additional color.   This seems to be a point of confusion to some guitarists as traditionally, guitar amps have been musical instruments in their own right, designed to have an impact on the sound.  The amp in the Unleash has a function much like the amp in a PA system or a home audio system, and that is to be as transparent as possible.  It does that job admirably. I never used the amp in a way that made me think I needed more power. 

When I set my rig up at practice, I realized I didn’t have long enough cables to connect the two time based pedals into the the effects loop, so they are not part of this portion of the review.

Neither of my band mates noticed any change in my tone throughout practice. They did notice that my sound was more dynamic and my amp now could deliver a great clean rhythm sound at volume levels that would have been distorted before.  What I noticed was that I could pretty much do anything I used to do with the amp sounding exactly like it did without the Unleash. But more importantly, I now could do all sorts of things I previously coudn’t do.

The ability to have a preset volume boost that doesn’t involve more distortion is hard to appreciate until you’ve tried it. Step on a pedal, and the sound gets louder, but the distortion level doesn’t change at all.  I’m going to have all sorts of creative things I can do with this.  And that brings up the entire point of the Unleashvolume and distortion are now independent of one another.  I can have set one level that can mimic the behavior of the 5E3, and another one that’s something else altogether.

My little 5E3 now has the clean dynamic ability of a much larger amp.   I can get piano like sounds from the lower two strings with the solidity, clarity and presence you’d expect from a Twin Reverb.  I have a Bandmaster Reverb in a combo cab with a Weber 15″ in it, and this rig seems to have similar dynamic capability: more than I’ll ever use.  I can’t quite describe what the amp can sound like when you turn up the volume a bit, Tweed Twin comes to mind, but it still has the Deluxe character, just “bigger”.  If I want more volume, dynamics, or a more robust bottom end I could add another speaker, or even something like a couple of 4 x 12″ cabs, but I don’t think I’ll probably resort to that extreme.

SONY DSCThe other use I’m planning to put the Unleash to is at home, where I’ve been using a Fender Greta to power an open back cab with a Jensen re-issue P12R speaker.  By and large it works fairly well, but sometimes It lacks the clean volume I’d like and sometimes it can be too loud, by the time It’s really singing.  The rest of the rig is as follows:

Squier Vintage Modified Telecaster Deluxe
SX Partscaster with single coil pickups
Joyo Ultimate Drive pedal (in front of the amp)
Boss GE7 EQ Graphic EQ (effects loop)

ModTone Delay (effects loop)
Biyang Tri-Reverb  (effects loop)
Fender Greta
Jensen P12R in open back cab 

And, Introducing the world’s first 160 Watt* Greta.

unleash 3

First off, the Unleash effects loop is even more effective in this application because I can hear every little nuance, nothing is covered up by the rest of the band.   I also have the option of popping the EQ pedal into the loop.   this is quite important for late night use, when I might not want to wake up the house. 

Normally when you turn an amp down to these levels they sound sort of weak and thin.  This is due to the Fletcher-Munson effect; human beings don’t hear all parts of the audio spectrum with the same intensity at low volume levels.  So, you can use the QP pedal to compensate and still hear a nice full bass at lower volume levels.   If you try this in front of the Greta (or any small amp), you end up with all sorts of distortion right where you don’t want it to be (try 12 Db of boost at 100 Hz and see what happens to your sound) and end up with muddy sound.   Not only does this not happen in the Unleash effects loop, but you can also use the EQ to shape the sound post distortion, which also comes in handy.

As far as transparency goes if the Unleash wasn’t transparent, as with the effects loop, I’m more likely to notice even slight changes in tone or feel when I’m just sitting in my living room without any other instruments.   The naked guitar sound really leaves no place to hide.    Trying my best to be “scientific”, I compared the sound from the Greta by itself with the sound from the Greta running through the Unleash.  I set volume levels with an SPL meter, so I wouldn’t favor the louder one, and tried my best to detect some effect.   Nada.

Again, there seems to be no downside, but the Unleash allows me to listen to the Greta completely cranked and drop the volume down to a level that doesn’t disturb anyone, and also to get a clean sound from the Greta and volumes that is is unable to achieve while remaining clean.

I should note that the only way to get the Input trim light to even flicker with the Greta is to crank it all the way up and then step on an overdrive pedal, and even then I’m not sure I actually saw it light.   But it will produce any level I’m willing to risk the health of the Jensen P12R (and my lease) at in my living room.  I’ll have to try it out with the other speaker at band practice to see how loud the combination will get.

Moving back to realistic volume levels in my living room, I’ve got to tell you that the Greta/Unleash is capable of making some glorious clean sounds if you turn the amp down to where you can just barely see the little meter on the face of the  Greta start to move It has the most wonderful character to it that I can’t quite describe and it brightens ever so slightly when you REALLY dig in to an almost exaggerated degree.   In this behavior, it actually reminds me of an old brown era Fender Pro Amp, that was my previous standard for bedroom level clean tone.

I’ve not begun to explore all the possibilities the Unleash presents.   I have a Fender Bandmaster Reverb that has a output transformer that can deal with an 8 ohm load (which the Unleash requires), but I’ll need to get inside the amp and swap the 2 ohm output (Which I haven’t used in months) with the 8 ohm one, so I can try it with the Unleash.  With that amp, I’ll mostly be using it to attenuate the level, as it’s usually not able to really sing at volume levels that are acceptable for the band I’m playing with.

I still haven’t even tried the line out level, so I will be exploring the uses of that, among other things.    I have another 5E3, so I can possibly try a wet/dry rig, and a host of other things.    I’ll report on these things as they happen.  If anyone is curious about something I haven covered, please send me an E-mail.

For an update on the Unleash (May 2014) and how my use of it has evolved at this point please click here:


Unleash Update


For more information, try the Badcat website:


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Photographs courtesy of: Pacific Coast Professional Services, Inc.

Author: fauxsuper

Guitarist since 1964, motorized vehicle enthusist all my life, Married with two step children. Born and rasied in Lebanon, Ore.

8 thoughts on “Badcat Unleash Review”

  1. Someone pointed out on a forum that they didn’t think a P12R would last long with a 100 watt amp. I think it will do just fine in my living room. I’ll never get even romotely close to it’s limits. The P12R is inefficient, as guitar speakers go, but both my Vox Lil’Night Train and Greta will make it play louder than I ever need in my living room.

  2. Used the Unleash with my Greta amp at band rehearsal today. I think I might like it better that I do with the 5E3. It’s a little hard to fathom quite what it sounds like, I mean there’s no frame of reference. It’s Fender-ish, but with a nice chime to it; still different than any familiar output tube.

  3. Great review! I happen to have a similar combo, Greta + Unleash into a Vox V112NT cab. It’s awsome!
    The only gripe I have with the Unleash is the fan, I wish they had put a variable speed or at least adjustable fan in there, it’s running on full all the time regardless of how much heat is generated.
    Obviously a Greta running clean into the Unleash at bedroom levels isn’t going to generate much heat, so a variable speed fan would be nice.
    But that is trumped by the general awsomeness of the setup, so all in all I absolutely can’t complain : )

    Gassing for a EH Holy Grail or T-Rex Tonebug Reverb pedal in the FX Loop now

  4. I used to have an old twin reverb, which loved pedals. After, I used an old super reverb, which is good with pedals, but not great. Now I have princeton reverb, actually two in stereo. I love my living room tone, clean with a little, little hair. Full band, and they scream, which is not exactly what im looking for. My delay and reverb is mush. I was thinking of picking up a couple of twins, which is pretty crazy and pricey.

    Now Im thinking of a couple of unleashes, and ill run my delay and reverb through the loop.

    Your honeymoon is over.

    I’ve read a bunch of reviews on people using it as an attneuator, and they were non-plussed. I’m not interested in taming a beast, I want to make a beast

    Advice please?

    and much thanks

    ps. ill probably get just one first and check it out, if you give the thumbs up. If I can get loud, clean princeton reverb, I will die!!!! a happy man

    1. Chris,

      Ironically, I just saw your comment as I’m headed out the door to band rehearsal. I do have a few thoughts on your particular situation, and will post them here either tonight or tomorrow—————

    2. The first thing I have to say is to ask you if you’ve ever heard your Princeton connected to a 4/12 cab. I had a 4/12 that I wired in series parallel to be an 8 ohm load and it amazed me how loud the amp was. I also tried the same thing with the 4 x 10″ set up in one of my Super Reverbs, and the open back enclosure made it sound a lot more like a gigantic Princeton, which the sealed cab 4/12 did not.

      In any case, I’d think what you want to do is quite feasible. The trick is going to be finding a speaker complement that can handle the power and still sound like your Princeton. For me, the neodymium magnet Jensen works quite well for this, with a Vintage American speaker signature to it and plenty of power handling. I also have a Texas Heat, but it’s a different animal altogether, making the Deluxe tone into a
      Mini-Marshall sort of deal.

      FYI I can understand the desire to run stereo, I’ve used stereo rigs in the past, and I enjoyed the sound onstage, but going out into the audience area with a wireless showed me that nobody out there could hear it. Soundguys were also not interested in having two feeds from a guitar player and I never found anyone running a PA in Stereo. That said, you could get by with just using one amp (But TWO unleashes) and generate the stereo image with your effects, and just take the output from the effects chain and feed right to one unleash and left to the other. unless you’re using different settings on your two amps.

      So, if running stereo isn’t a major deal to you, I’m thinking a single Princeton/Unleash should be loud enough for most situations. I think where people screw up with the unleash is by turning up the “host” amp up too high, I run my Deluxe Clones at around 3 (when using a humbucking equipped guitar, I use about 5 for single coils) and am able to generate enough distortion to make me happy most of the time. Turning the volume up higher and controlling distortion via the guitar’s volume knob works if you need more hair or want endless sustain, but I find that keeping the amp’s volume pot low and using the Unleash to get the volume works the best for me, and gives me a lot more clean headroom. I also am not a “purist”, and use an OCD pedal for a little more grind and tonal shaping, and it works if I need just a bit more crunch or compression.

      The first impulse with any attenuator seems to be to turn the amp up louder than you’ve ever been able to use it and I think this is why people are disappointed. I’ve used Hot plates, Weber MASS, and a couple of other attenuators and find they were best if you use your normal amp settings and only use about 6 DB of attenuation, at most. Great at knocking something like a twin down to about the same level as a Pro or Vibrolux Reverb, for example. Not so good at taking a twin, cranking it, and trying to throttle it down to conversational levels to record.

      Since you like the way your Princeton sounds in your living room, I think you’re a perfect candidate for an Unleash, as it should be pretty easy to just scale that sound up. You may have to turn up the treble up a little more and back off the bass a little to get the same tonal balance as before, but I’d ignore the tone knob positions and adjust by ear, till you find the right balance. I’d start low with the volume setting on the amp (using the Unleash to set the ultimate sound level) and slowly work your way up until you find something that sounds right to you. It’s kind of counter-intuitive to set the volume on the unleash, as you don’t get more distortion by turning up the volume, just more volume. I wouldn’t stress to much over the Input Trim level: as long is the light isn’t totally on or off all the time, you’re into the right ballpark and you can futz with final adjustments when you get your levels set.

      I’d get familiar with the unaffected sound before you plug in the effects, as it takes one variable away for a bit, at least.

      Since they are not getting distortion added to them, they should sound a lot more distinct and I find I don’t turn them up as loud as I used to as I can hear them so much more clearly. It’s hard to go back to having them at the front of an amp when I play without an Unleash.

      I hope this is the sort of stuff you were wondering about, but if I haven’t touched on something, please let me know. I’d also love to hear how it all works for you.

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