Gear Lust 05/2010
Barry Rudolph: "I'm highly recommending the mpressor for its versatility and unique abilities not obtainable with any other processor. It excels especially in the creative side by radically altering the dynamic envelope of sounds yet it can also behave very civilized when you require. The negative ratio and Anti-Log release mode are strictly fun!"
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Future Music 02/2010
Stuart Bruce: "From subtle but controlled compression to radical pumping, tonal shaping to complete changes in the feel of a groove, the Mpressor will certainly make a mark on your music. Add to that great sonic quality and this is a very powerful and musical tool that you’ll find yourself reaching for every day."
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Keys 02/2010
Martin Keller: "The mpressor can be used on versatile occasions  […] The sound is excellent, clear and warm with a high resolution. The special features like Anti Log and negative ratios described above allow deep transformations and manipulations which point out the mpressor's qualities as a unique tool."
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Delamar 01/2010
Mario Laemmerhirt: "If you ask me, elysia have kept their promise all along the line. I, for one, could not find a fly in the ointment. The mpressor cuts an extremely fine figure when used as a creative sound shaping tool. I experienced its interesting compression effects to be very convincing. My new reference class."
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Apfelwahn Music 01/2010
Heiko Wallauer: "This plug-in is certainly not a one-trick-pony, but a very flexible one instead. No matter if you want to compress acoustic instruments the decent way, or raise the pressure on drums, or create spectacular effects – the mpressor does it all. With its many special features it convinces all along the line."
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Audio News Room 01/2010
Fab: "One of the most original compressors of our times, faithfully modeled and ready to be used on multiple tracks on your DAW. The mpressor can be an excellent all-round compressor, but to me it really shines on more experimental tasks, thanks to its unique controls."
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Sonic Scoop 01/2010
Geoff Sanoff: "The mpressor definitely has a color to it, though it’s a color with many gradations of density and tone, far more than most compressors. While it does transparent reasonably well, it does character much better. […] What the Distressor has become to modern recording, the mpressor plug-in may well become to in-the-box mixing."
> Read more... 12/2009
Klangfabrique: "The mpressor shines because of its sonic qualities, its accurate and solid dynamics processing, its flexibility and its intuitive operation. Its functionality outranges normal compressors by offering new and and almost playful ways to create unimagined soundscapes. The title 'creative compressor' is justified by all means."
> Read more... 12/2009
Andreas Ecker: "The mpressor is absolutely convincing: sound and flexibility are top notch. My earlier favorites now have to face a serious rival, as because of its special features it beats them as an allrounder with a good lot of esprit."
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Guitarlounge 12/2009
Ludvig Nylund: "The mpressor is modern and versatile, it’s clean and tight, when you want it to be breathy it breathes, when you tell it to be subtle and transparent it obeys and if you throw it out there to be whacky and angry it does that just as well… all while retaining stellar quality."
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Mpressive Software Emulation

by Gunnar E. Olsson
Monitor (Sweden) – March 2010

In June 2007, Monitor Magazine tested a piece of gear that truly belongs to the most modern and high end compressors in the market ever: the elysia alpha. A little bit later, the competent Germans introduced an equally inspiring follower: the mpressor. The price tags for these hardware monsters prevented many smaller studios from using their advantages, though. Now this problem is solved by introducing a software version of the mpressor.

The price of an alpha is around 8,000 Euro excl. VAT and the mpressor is not that far away with its 3,500 Euro. The software version addresses smaller studios and musicians, however. Our editor Jörgen Cremonese is still of the opinion that the alpha which he titled 'Miracle Machine' is worth every Cent of its price, but a price tag of around 290 Euro for the software version of the mpressor pleases the eye much better. This price seems to be much less daunting.

The cooperation with another German company (which is Brainworx who have also programmed the software versions of the SPL hardware – Monitor 07/09) made it possible to emulate the very sophisticated mpressor hardware, which is a fully discrete design running in class-A mode. And without exaggeration one can say that the mpressor (just like the alpha) is truly impressive, and it also sounds this way.

The mpressor is a stereo compressor with the possibility to run its two channels linked or separate from each other. The compressor can be triggered from external source signals (side-chain) and it can be used as a universal and flexible tool for many tasks, even for mastering. In order to be able to use the sidechain functionality, your host software must support this feature, but most of the actual versions do this anyway.

But the mpressor also offers some special functions which have partly been borrowed from its big brother. 'Auto Fast' means that the attack time is automatically adapted to the source material, becoming very short on fast transients. elysia aimed at keeping this functions free from artifacts, and they obviously succeeded in doing so.

The 'Anti Log' for the release curve results in a different sound character than we are used to, and it can be used to create some very interesting sound effects. In this mode, the beginning of a signal is processed with a longer release time which is shortened while the signal sustains. If you want to get those drums pumpin', just activate the Anti Log function.

The 'Gain Reduction Limiter' is not the standard limiter you might have in mind. Instead of limiting the audio output level, the Gain Reduktion Limiter controls the maximum allowed amount of gain reduction instead. For this reason, the limiter is not placed in the audio path, but in a place where it can have its influence on the virtual control voltage. This means: not matter how high the input level is, the compressor will never process a signal any stronger than you have allowed with the GRL controller. This way, the weaker signal parts can be compressed while the dynamics of the stronger signal parts remain intact – opening the floodgates to creative musical ideas.

The 'Niveau Filter' is another great function which can be used in very creative ways. It is similar to the tilt filter type that can be found on some HiFi products. It influences both sides around a selectable center frequency differently and can shape the tonal balance radically with just two controllers. The first pot sets the center frequency, and the second one sets the intensity of the filter's effect. The basis for this EQ Gain controller is the middle 0-position. When it is turned clockwise, the bass is boosted and the treble is cut at the same time. When turned into the other direction, the effect works the other way round. Finally, there is an additional button which multiplies the chosen frequency times ten. Very effective! In the outer regions of the EQ Frequency controller range the character of the filter changes, becoming a low pass filter or a high pass filter respectively in the extreme positions of the controller.

The function 'Negative Ratios' should not be mistaken for expansion. With the usual ratio settings used, the mpressor behaves like a typical hard knee compressor, and the ratio curve changes in the typical way once the threshold has been passed. When negative ratios are set, though, the curve goes back down again. This means: The stronger the input signal is, the further it is bent down. In combination with the other specials of the mpressor this gives you the possibility to create fascinating sound collages. Echo and reverb effects can be given a life of their own. However, the M/S matrix of the alpha compressor has not been included. If you are looking for something like this, Brainworx offers some very interesting products here (

If you need some help, you can download a manual in PDF format. This manual has a good structure, is well written and really does what it's supposed to. It provides lots of demo settings which can be used as a basis for your own work. A difference to the hardware is that the software does not have an individual set of controls for its left and right channel. When two single mono channels are to be compressed, two channels of mpressor have to be opened. But this does not require too much CPU power, therefore quite a lot of mpressor instances can be opened at the same time without the processor getting into trouble.

The mpressor has all the controllers you would expect to see on a compressor: Threshold, attack, release, ratio, make-up gain and an LED meter that shows the amount of gain reduction and eventual activity of the Gain Reduction Limiter. On top of this there are some controllers and buttons for the additional special features of the mpressor.

But even with all these fantastic advantages, the software has a little problem. The construction of the hardware is incredibly solid, with metal knobs that ooze quality in all their aspects. But the attempt to emulate this in all its aspects in software can cause some problems concerning the interface design. While the three-dimensionality and the illumination of the hardware are a good help, the values on the software front panel can be hard to read. Especially the numbers around the pots could benefit from a larger size. Of course this is a matter of taste, and a monitor with a different resolution could improve the situation. However, I had some difficulties in reading my settings from time to time...

The mpressor has all the possibilities you would expect from a top class compressor. It works exceptionally well with all conventional settings – and the same is true of its sound. Experimenting with the Auto Fast, Gain Reduction Limiter and Niveau Filter features results in sounds that only very few other units can generate. 'Transparency' is not really the first impression which comes to mind then, but it's also not ment to be. To sum it up, the mpressor easily covers the complete range of possible sounds – from discreet and transparent processing to very punchy sound effects. It's getting full marks for its sound!

I was not able to provide a direct A/B test between the hardware and the software, but I can't get rid of the impression that the transfer of the hardware mpressor's motto – sound quality without compromise – went really well. The software works as fine as a mixing and mastering compressor as it does as a creative sound tool. Working with the mpressor is extremely easy, but it is full of great surprises at the same time. And should you still be in doubt after reading this: there is a trial version that can be downloaded from the manufacturer's website. All you need is an iLok. My opinion: very mpressive!