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Jackson Audio Bloom Compressor Review

There's a lot crammed in to this compressor and it sure is shiny. It's a heavy and very solid feeling pedal. Certainly very attractive and very well built.

The Bloom is an optical circuit and also features a three band EQ and the Bloom circuit. More on that later.

There are 7 knobs and two foot switches.

Volume acts as a master volume for the primary compressor section. Essentially your makeup gain.

Blend allows you to blend in your clean uncompressed signal with the compressed signal. Full counter clockwise is full compression. Fully clockwise is full clean signal.

Comp controls the amount of compression. Turn clockwise for more compression. This control reacts differently depending on which compression mode you have activated. More on that later.

Those three controls essential form the compressor circuit but then there are six different compression circuit presents. More on this later.

Jackson Audio says the three band EQ circuit is based on the legendary Baxandall EQ that is featured in countless studio EQ’s, but is tailored for guitar. Unfortunately, I found very little to like about the EQ circuit as all of the EQ points were not ideal to my ear. There is center detent for each of the knobs. Turning the bass frequency knob clockwise from center detent just makes for a boomy sound lacking any real definition. Treble boost adds noise and gets shrill real fast. Midrange is the only one I found somewhat useful. The EQ is activated by pressing both foot switches simultaneously. That works OK.

The foot switches themselves have a nice feel and are the silent clickless type.

Now let's talk about the compression presets as this is probably the most compelling feature of the pedal. Well that and possibly the Bloom control.

There are six instant access presets with the following settings (per Jackson Audio documentation): • Preset 1: Limit Mode. Ultra fast attack (2.5ms) that clamps any signal and acts as a limiter. • Preset 2: Country Mode. Fast attack (7.5ms) that is perfectly timed for chicken picking or modern country. • Preset 3: R&B Mode. Medium attack (50ms) • Preset 4: Ballad Mode. Slow attack (120ms) setting • Preset 5: Slide Mode aka ‘Joey’ Mode. Adds an additional internal compression stage in series before the primary compressor. Allows for nearly endless sustain on clean guitar parts ala Lowell George from Little Feat. • Preset 6: Aux Compressor. The aux compressor is the internal compressor circuit that is used in Preset 5. There are two trimmers located on the side of the pedal that allow the user to adjust the COMP and VOLUME for this additional compression stage.

These trimmers are inside the pedal and frankly, the enclosure is a challenge to take apart so I never bothered to mess with the trimmers. Honestly, I didn't find really any of the presets all that exciting. Limit mode is OK if you are looking for a limiter but is not the same league as the likes of the Keeley Bassist or Empress. Presets #3 and #4 were the only two I was interested in and neither do all that much for your tone. The inherent sound of the pedal in general is very, very transparent. If you just want a little smoothing out, either preset #3 or #4 could be useful. Presets #5 and #6 really have no value for bass guitar.

Pressing the Comp footswitch activates/deactivates the compressor. To select a compression preset, press and hold the COMP footswitch for more than 1 second. Doing so will activate the compression program. When in this mode, the COMP led will flash to indicate that you are in program mode. A quick tap on the COMP footswitch will cycle the compression presets and you’ll be able to hear these preset changes as you cycle through them assuming that the compression circuit was active when compression program mode was entered. Once you arrive at a compression preset that you want to use, press and hold the COMP footswitch for more than 1 second and compression program mode will exit.

There is also a Side Chain jack/loop that allows an external source (click track etc) to trigger compression. Side Chain loop can also be used with an external effect (an EQ for example) to tailor the response of the compression circuit. The Side Chain jack is in between the Input and Output jacks at the top of the pedal along with the 9 volt power input.

So what's the deal with the Bloom control? It is designed to be both a level booster and sustainer. You can set the Bloom circuit to work as a boost by quickly pressing and releasing the Bloom footswitch. By pressing and holding the Bloom footswitch, the Bloom circuit will slowly ramp up the level to the level set by the boost. I can see the latter option being potentially useful if you want to ramp up a volume level at a certain point in a song. As a boost, it works great and is a valuable addition to this complex pedal. When the Bloom is activated, turning the Bloom control will change the Bloom led to indicate the amount of boost present.

Per Jackson Audio documentation, here are the specs of the Bloom circuit: • 0-20dB Boost Available (quick press on Bloom footswitch) • 0-20dB Bloom Available (long press on Bloom footswitch) • True Boost Circuit. Fully counter clockwise position is unity level. • Totally flat EQ down to sub audio frequencies. • Programmable Ramp Up/Down Time.

To activate the Bloom feature (slow fade up to boost level) press and hold the BLOOM footswitch for more than 1 second. The inverse is also true. To fade down from a boost setting, press and hold the BLOOM footswitch for more than 1 second.

To set the period of time that it takes the Bloom feature to reach the set level of boost, press and hold both the COMP and BLOOM footswitches simultaneously for more than 1 second and ramp program mode will become active. When in this mode, the BLOOM led will slowly fade from off to full brightness at a regular interval with the BLOOM knob setting the duration of that interval. The fade time is as quick as 1 second at the full counter clockwise position of the BLOOM knob to as much as 5 seconds at the full clockwise position of the BLOOM knob. To save this setting, press and hold both the COMP and BLOOM footswitches simultaneously for more than 1 second and ramp program mode will exit.

The LED's are cool and very dynamic. The Comp LED will changes both color and intensity as you cross threshold.

The EQ LED illuminates when the EQ is activated but the EQ also changes color based on how the Bass/Mid/Treble knobs are adjusted.

The Bloom knob blooms with the blooming of the sound. You get a nice light show when powering on the pedal. See the next four pics showing the rotation of color as you turn it on. Really cool.

I had high hopes for this pedal and in some ways it is really cool — The technology certainly is and there is really nothing like it in that department.

Overall its just OK though.

Unfortunately it does not handle high output basses well at all. It distorted with all of my active basses but sounded decent with a passive. In the tonal department it neither adds anything special to your tone nor does it really sweeten things either. It is very utilitarian in that way. It doesn't really add or cut highs and lows. Only a couple of the compressor presets were really all that useful (to me anyway).

The EQ is much better suited for guitar than bass.

With my Fender Strat, well it's a totally different story. The Jackson Audio Bloom takes on a new life and is really quite pleasing. But since this is a review for bass, well, other than it's cool vibe, it is pretty lackluster.

Retail price: $329


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