Music Store 09/2012
Daniel Škrášek: "The xpressor is something new, something different, something interesting and something fascinating. Many times I found myself experimenting with different settings for hours. Everything sounded good, all of the time, and sometimes the results can only be described as fantastic."
Read more...

Producao Audio 06/2012
Miguel Pinheiro Marques: "The xpressor is truly a swiss army knife when it comes to audio compression, because it can handle every type of instruments, groups or mixes in very transparent and musical ways. And the most amazing thing is that elysia made this incredible tool at a very affordable price, which makes it a no-brainer purchase."
Read more...

Keys 01/2012
Tim Schuldt: "The xpressor convinces in every aspect. It combines extreme flexibility with premium sound qualities. No matter if used on single, group or sum signals, the results are always positive and versatile. Because of the delivered quality, the price results in a very good value for money ratio. And the xpressor does not have to fear the competition of much more expensive units at all."
Read more...

Studio Magazin 10/2011
Fritz Fey: "The xpressor meets the requirements for being used in professional environments in every single aspect, and it outperforms considerably more expensive competitors easily. Never before has such a high level of technology in combination with such a creative concept been offered for so little money. The xpressor defines a new value for money class which stands unequaled today..."
Read more...

Dynamics Chamaeleon

by Georg Berger
Professional audio (Germany) – November 2011

With their new xpressor, German pro audio manufacturer elysia now also offers products in the lower cost range with the explicit aim of not making trade-offs in terms of sound. The review tells you what this nifty looking 19“ compressor is capable of, what is special about it and if it is worth a purchase.

If you did not have elysia and their hardware products in focus so far because of the high (but justified) price tags, it has become time to think differently in the meantime. Already since the 2010 the manufacturer offers the xpressor 500, which is an affordable VCA style compressor in module format for API's 500 series, inheriting quite some of the genes of its bigger brothers, the alpha compressor and the mpressor. The people behind elysia, Dominik Klaßen and Ruben Tilgner, proudly tell us that this product has become a true bestseller since its release. Just recently elysia has also released a rack version of this compressor with the plain title "xpressor". 

The price tag: 990 Euro excluding VAT. This might sound a little high when compared with the 500 series module which costs 650 Euro excl. VAT. But the difference in price puts itself into perspective quickly, as the upcharge gives you a housing of its own, an integrated power supply plus an external sidechain which could not be fit on the 500 series variant. Finally, there is some additional electronics for the inputs and outputs. Apart from this, both product variants are identical. Both xpressors feature parallel compression, negative ratios and a number of further special elysia highlights like the Gain Reduction Limiter as well as switchable Warm and Auto Fast functions. These features give the xpressor a distinctive profile and augur well in terms of dynamics and sound processing. But one thing after the other. Let's have a closer look at this hardware first.

Discrete class-A design
The rack unit takes one U and weights only two kilograms, so it is a true lightweight indeed. This could be achieved by a thin full aluminum enclosure with. This is something we do not see often, but there is nothing to complain about in terms of stability at all. The same is true for the controllers and connectors, which are fixed absolutely bombproof on the front and back panels. All inputs and outputs are available as parallel pairs of XLR and jack connectors, plus there are two additional jacks for an external sidechain send and return. 

The labels "EXT 1" and "EXT 2" might be a little bit misleading at first, because one could think that both channels have an external sidechain of their own. However, the xpressor does not operate in a dual-mono mode, therefore EXT 1 is the input for external sidechain keying, while EXT 2 is a send output. Talking about dual-mono, this might have been a nice addition (which can be found on some other compressors as well). However, it has to be taken into consideration that this feature could only have been realized with additional effort in terms of components. This would certainly have had an effect on the retail price of the unit, therefore we do not look upon this as a minus. 

Back to the sidechain: More obvious labels would certainly have been nice. But still, the great thing is that these two connectors let you insert external hardware into the xpressor's control path without any additional efforts. The sidechain send carries a mono signal which is a sum signal generated from both stereo channels. Another interesting aspect of the xpressor is its power connector which as been place right in the middle of the back panel. The reason for this becomes obvious after removing the top cover of the housing: The left and the right side holds two well-arranged, symmetrical PCBs for each stereo channel, leaving space for the power supply in the middle of the housing. By the way, both compressor variants use the same boards for the audio circuitry. In combination with employing SMD technology for placing the components on the boards, this helps to keep the retail price of the product down. 

While component placement and soldering is done through an external company, completion and quality control is done by elysia themselves. The connection of both compressor boards and the mainboard with the audio connectors is done via additional mini PCBs with connector sockets. This is reminiscent of elysia's high end products, in which the audio signals are also not routed through any cables in favor of audio quality. The only cables we can find in the unit carry control voltage solely. Obviously, not all components used in the xpressor are the same as in elysia's high end flagships. 

However, while talking to the elysia crew (they personally visited us for bringing in the demo unit) it became obvious quickly that they did not allow any compromise in terms of quality and accuracy. The clean 'guts' of the xpressor speak for themselves. The circuitry is a fully discrete design – standard OP amps were consequently kept out. As one example, the circuitry of the input and output stages has been taken from the 8.000 Euro alpha compressor. 

Many features of the high end units
On the front panel, the high grade knobs made of milled aluminum positively invite to start processing some signals. Behind these, there sit regular carbon potentiometers with 41 steps, which is great for precise processing and an easy recall. The clou here is that at no time any audio signal is sent through these pots, avoiding unwanted signal degradation. The potentiometers just provide control parameters for the electronics taking care of processing the audio. 

The only exception is the potentiometer for the sidechain filter, but even here the audio signal is just being used for generating a control voltage. Apart from this, the front panel features a number of push buttons and an LED chain for metering the gain reduction as well as the backlit elysia logo disc. As a first conclusion, the xpressor convinces with its build quality and its many finesses in terms of circuitry and construction. These facts let the xpressor stand out of the crowd of many industrially manufactured products and absolutely justify the retail price already. 

But this has just been the beginning. Off the beaten track of the usual control options of a compressor, the xpressor boasts with a number of functions which have been taken from the boutique processors, now being available in the mid price range as well. The first highlight to mention is the switchable Warm function which allows for a little bit of sound coloration just before the output stages. Technically this is done by a slewrate limiter which slows the speed of the output stages down a little bit, which results in a slight boost of the bass frequencies while rounding the treble a little bit while producing additional harmonics at the same time. 

The next big thing taken from the high end machines is the Auto Fast function. What makes this function brilliant is the fact that it only reacts on fast transients by reducing those spikes extremely fast and independently from the original setting of the attack controller. After this, the attack value automatically returns to the value which has been set with its controller, which can be compared with a Peak and RMS compression. The unbeatable advantage of this is that you can choose a moderate attack setting which does not over-compress the complete audio material. The rest is conveniently handled by the Auto Fast function. Similar to the mpressor, the xpressor also features a selectable release curve characteristic which can be changed from linear to a logarithmic progress. 

When switched to logarithmic mode, the return to the initial level feels more vivid compared to the linear curve. In other words: The stronger the amount of gain reduction is, the faster the release time will become. Another feature taken from the mpressor is the Gain Reduction Limiter which basically defines a second threshold. This function defines a maximum amount of gain reduction after which the compressor does not reduce the level any further. This results in loud passages of a sound keeping quite a bit of their original dynamics, because they will not be compressed beyond the value set with the GRL controller. 

For example, independently from the level of the track or the settings of the other controllers, the maximum amount of gain reduction will never exceed 6 dB when the GRL controller is set to this value. This also enables the user to employ ducking and upward compression effects by only rising the low-leveled signal parts without changing the overall dynamic structure. Compared to this, the integrated sidechain filter (which can be set from 31 Hz to 1 kHz) and the Mix controller for parallel compression are much easier to get one's head around, but in many competitive products these features are not found at all or just in a reduced form. 

Flexible and creative in use
Packed with specials, the xpressor manages to set itself ahead of the competition in its price range significantly in terms of features. The tried and trusted functions taken from the bigger brothers make the xpressor a clever and practical problem-solver for any standard task, but at the same time they open the door for many creative possibilities as well. The great flexibility of the xpressor shows again during the technical measuring session, which became something like a measuring marathon this time. It would have taken the complete article to list all results and findings, as there are so many aspects to consider. 

For example, the measurements of the FFT spectrum show many different results with a lot of variants of the harmonics, depending on the positions of the GRL, threshold and ratio controllers. The same is true of the total harmonic distortion factor, which makes the xpressor – depending on the settings used – everything between clean and colored. The big picture shows the xpressor as a unit with excellent measurements which identify it as a top class unit. From our measurements you can see the huge influence the setting of the Gain Reduction Limiter has on the results. 

During our listening session the xpressor played against the gallery and completed the superb impression it had already left on us. The manual which welcomes the user with the title "Welcome to compression wonderland" really nails the sound qualities of the xpressor in every aspect. This compressor can be subtle and transparent, but it can also have a powerful and colored side if needed. It is striking how carefully the xpressor treats signals on moderate ratios, which sometimes made us set higher ratio values than we might usually do. 

The characteristic curves of the compression speak for themselves, showing the results of its soft-knee approach. Sometimes you really need to switch back to bypass in order to realize and understand where and what the xpressor processes. The way it compacts signals is organic and smooth on the highest level, while the vividness of the signal remains unchanged, making it very useful for mastering applications. The icing on this cake is the additional features for the time constants, as they let the user process even critical material successfully. For example, all of a sudden it is easy to get rid of nasty transients from a snare with the Auto Fast function activated. The drum groove we used for our test sounded much more compact and whole as if by magic. 

This also eliminates the need to use a second compressor for catching the transients. And the switchable release characteristic does a tremendous job as well. Audible pumping effects on drum tracks simply vanish by just the push of a button. The combination of these two features somehow seems to give the xpressor some kind of weird intelligence which is even foolproof in use. The Warm function gives the user an additional option for influencing the sound character. When used on a bass line, for example, you notice how the sound gains in volume and body in subtle, but certainly audible ways. 

Vocal tracks also sound more full, a tad nicer and more pleasing. But this is just the one side of the story, as the xpressor can also be a powerful dynamics tool for influencing signals with very obvious results. If both the attack and the release controller are set to their fastest value, instant distortion will occur. Taking the actual values of 0.01 milliseconds for attack and 5 milliseconds for release into consideration, this does not really surprise. Striking effects can also be generated by setting negative ratio values which can do everything from pumping and reverse effects up to the total destruction of audio signals. 

The expression "compressed to fuck" sounds just appropriate in this regard. But with the help of the mix controller and the ingenious Gain Reduction Limiter (which we from now on would really like to see on every compressor) these effects can be applied in fine doses. The combination of all the features mentioned makes the xpressor a powerful tool for dynamics and sound processing. Working with this compressor during our tests was big fun and very inspiring indeed. Last but not least, we could always find useful settings in a very short time. 

Conclusion
The rack version of the elysia's xpressor is a high-flying dynamics processor which is great for mastering, sound design and processing single tracks. The spectrum of its options is simply amazing and real-world proof at the same time. But this dynamics chameleon does not only stand out of the crowd because of its special features. Its construction and build quality are absolutely breathtaking. Looking at the qualities of the xpressor, elysia could have sold it for twice the price easily – and because they didn't, the value for money rating must be estimated as phenomenal. 

Pros
+ Excellent sound character
+ Flexible and creative processing styles
+ Many features from the boutique units
+ First class build quality
+ Universal qualification for mixing and mastering

 Cons
 

Result
 
= With the elysia's xpressor the user has a universal tool which offers high end features at a low cost price. This unit clearly reveals of what compression is capable of.