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Tsakalis Audio Works Zipper MKII Compressor Review

Chris Tsakalis has been repairing gear in Athens, Greece for years. New he and his team are hand building a growing selection of pedals with a mission to keep them simple and easy to use.

The Zipper MKII optical compressor is inspired by the Urei® LA3A® with its simplicity and warmth. What Tsakalis delivered is all that plus plenty of punch, a ton of headroom, and a quiet circuit.

Sometimes compressor pedals that are designed to be simple with just a couple of controls seem like a great idea but just don't deliver. The Zipper really surprised me. It certainly is simple to use with just two dials and one toggle. But it is more than a one-trick-pony. Read on.

On the one hand, the Zipper can be used quite effectively as a clean boost. Simply turn the Compress dial all the way counter clockwise and that's what you have. Clean, unaltered dry signal, only boosted a little or a lot.

On the other hand, The Zipper is a very pleasant optical compression engine that leans towards the transparent side of the spectrum but not without a little special sauce thrown in. It is one of those devices where you don't want to turn it off.

The Level control adjusts the volume of the pedal. There is plenty of gain on tap. More than enough to make up for lost volume even at higher compression settings.

The Compress dial adjusts the threshold of the compression.

Finally, the toggle switch is marked Hard and Soft. In the downward (soft) position, the compressor is set to a 4:1 ratio. In the up (hard) position the compressor is in a 10:1 ratio.

At the lower end of the Compress (threshold) range, say between 8:00 and 10:30, the output seems to actually add a little low end. In reality I think it is more tightening of the lows with the result being a nice smooth big bottom.

With the Compress (threshold) dial at noon and higher the compression really does start to feel more squashed and even but in a very pleasing way. Sometimes compressors can suck the life out of your tone. Not so with the Tsakalis Zipper. Even with the Compressor (threshold) dial set to 3:00 or higher (lowering the threshold at which the compressor is kicking in) the device is highly usable. This is especially true when the toggle switch is in the Soft position. But when you flip the switch up and set the Compress dial to 3:00 or higher, the Zipper is still a practical compressor. It feels so smooth and even yet still somehow allowing a little dynamic expression to leak through.

There are some limitations though. The Zipper MKII is not a great limiter. Even at 10:1 and the Compress dial all the way up it won't squash everything. At the same time though, there is no dip and swell that plagues other devices. If you are a slapper, I'm going to suggest you try this one. I suspect you will find yourself attracted to the way it responds to evening out your tone without sucking the life out. Snaps and pops still come through but with a polish and evenness that I suspect will put a smile on your face.

There are no controls for attack or release. There is no compensation for variances in input though I had no issue with headroom with any of my basses, including a Sadowsky with strong preamp. I tend to prefer compressors that offer attack and release but the Zipper seems to dynamically react to playing style and I didn't often feel the need for independent attack and release controls. Remember, the Zipper is about simplicity.

The Zipper won't highly color your tone. Don't expect some sort of obvious tone magic but there is something special going on. As soon as I turned it off I immediately wanted it back on. I'm not going to call it transparent but will classify it more on the clean end of the spectrum of compressor pedals. That said, it is is not sterile. It adds a nice fullness that is very pleasing.

The Zipper reminds me of the Rothwell Love Squeeze in that it is a simple two knob device (with one switch) that adds a little something special to your tone. I prefer the Tsakalis Zipper. In fact, the Tsakalis Zipper MKII is my favorite two dial compressor I've tested to date.

The LED illuminates an orange hue when power is applied. There is no LED indicating threshold or gain reduction. It is pretty obvious to hear what the Zipper is doing though and that's part of its beauty. Somehow it remains relatively clean, yet adding something special, while providing plenty of versatility.

The Footswitch is true bypass. There is room for a 9volt battery inside the enclosure. Power required is 9 - 12 volt DC though I noticed no difference operating the pedal at 9 or 12 volts.

Whether playing bass or guitar, the Zipper is a great simple option. It seems to be well made.

If you are in the market for a simple compressor that won't highly alter your tone, take a look at the Tsakalis Zipper MKII. You'll also be rewarded with more punch and smoothing (evening) out of your tone.

Retail Price: $185


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