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Solid State Logic X Rack 2 Bus Compressor
4.25 4.25 out of 5, based on 2 Reviews

The SSL X Rack 2 Bus compressor gives that famous clean snap, and punchy sound that you hear on thousands of records out there. Nothing can quite replicate what this unit does incluidng the plug in versions from many company's.

12th May 2018

Solid State Logic XR626 Stereo Bus Compressor Module for X-Rack by Glenn Bucci

  • Sound Quality 5 out of 5
  • Ease of use 5 out of 5
  • Features 5 out of 5
  • Bang for buck 4 out of 5
  • Overall: 4.75
Solid State Logic X Rack 2 Bus Compressor

The Solid State Logic stereo bus compressor has been used on thousands of records over many years. It’s known to add that snap and attack that makes it so unique compared to many other compressors out. The 1U G Series compressor has been around since 2005, and before that model there was the G384 compressor in 1991. The main difference with the older units’ is the VCA started to roll off around 40kHz while the newer ones start to roll off higher.

Compared to the 1UG Series compressor, the compressor on the XL Desk, AWS, Duality, X Rack, and 500 versions have additional ratio (1.5:1, 2:1, 3:1, 4:1, 5:1, 10:1) and release settings (0.1, 0.3, 0.4, 0.8, 1.6 and auto release) compared to the 1U G Series compressor (ratio of 2:1, 4:1, & 10:1) and release settings (0.1, 0.3, 0.6, or 1.2s, or an automatic release) making it more flexible. The 500 series even added a hp filter for added flexibility. However the X Rack unit has a Key in aka side chain, you split the input out into a filter/eq and then back into the key in. Plus many times you will use the compressor with a slow attack and a faster release, so I don't find I miss this feature.

I personally found the auto release to work very well on many situations. A common setting for a 2 bus is the attack on 10, release on 2, ratio on 2:1, and the threshold adjusted to about -2db with the making up gain up.

What makes the X Rack version very attractive is the ability to save your settings. You simply save your setting on the X rack with the record buttonand to recall, you just dial the number you saved and push in the knob. The lights around the knob will either be green or red. Turn them to the left if its green and turn to the right if its red. When the light disappears the setting is back to what you saved it at.

The UAD SSL Bus Compressor plug in (ver 2) is the closest to the hardware that i have experienced. The UAD version sounds great and anyone with a home or project studio, you will do just fine without the hardware version and you will save a lot of money. The plug in will help add that forward sound to your mix quite well. The difference is not that big and on standard car speakers, the general public would not notice the difference.

Is the hardware different enough to justify paying additional thousands of dollars for the serious engineers and artist who take their music further than making music for yourself and friends? For about a 10 percent difference, I would say yes. I found that software company's can model EQ's closer than they model compressors due to the complexity of compressors.

The hardware brings forward the vocals and instruments in a mix that adds this energy and excitement that the plug in lacks. I heard the delay of a guitar more clearly in one example I tried it on. The reason is, it brought it a little more forward than the plug ins out there. There is also the fun factor when using hardware over using a mouse and software. But sometimes (like any piece of gear) it's not the best choice for a song based on its style or perhaps the way it was recorded. I found with some music, I preferred my Rupert Neve Portico 5043 compressor when I needed more weight, and or color added it a mix.

This compressor is a classic, and you can hear why once you use it.

Last edited by Glenn Bucci; 12th May 2018 at 11:38 PM..

  • 5
1 week ago

Solid State Logic XR626 Stereo Bus Compressor Module for X-Rack by onezyoung

  • Sound Quality 5 out of 5
  • Ease of use 5 out of 5
  • Features 2 out of 5
  • Bang for buck 3 out of 5
  • Overall: 3.75
Solid State Logic X Rack 2 Bus Compressor

I am an enthusiast of G Bus style compressors. I owned WesAudio Dione, Alan Smart C1LA, and LOADS of plugin versions of the iconic G Bus compressor. It took me about 4 years to get my hands on a real SSL bus comp. It's because I never thought of getting one. I can proudly tell you that I am not one of those who blindly believes in Brand, Original and Price tag. I strongly believe that with today's technologies, it is possible to replicate the unit and the sound with very close results. But yet, here I am.

Most people do not know that the SSL XLogic and XR626 are based on the bus compressor on 9000 consoles, not 4000. It is written on the manual if you do not believe me. This is why some people feel disappointed about these two models, because they are expecting the sound of 4000 bus comp. 9000 consoles have much cleaner sounding than 4000 consoles. I never had chance to lay my hands on either of them but at least this is what everyone said. I guess it could be because of the Superanalogue" technology from SSL. It doesn't have capacitors, instead it has DC coupled signal path delivered very high bandwidth with extremely low distortion.

I used to chase the snappy sound in the hi-mid of 4000 bus comp, the C1LA does a very good job on it. But then I found that I want something more transparent. "Transparency" is a word I fear for many years. Like most of the people who started investing in analog gears, "Why would I want to pay thousands of dollars for something that doesn't add mojos to my mix?". I asked this same question to myself for years, until I tried this 9000 bus comp.


Clean: It does not smear the sound nor adding too much distortion unless you slam it. But don't get me wrong, clean doesn't mean boring. It could add so much excitement to the mix!

Punchy: You can still hear some iconic character of a SSL bus comp, but you will not hear the snappy high mids as much as the 4000. Instead it sound very punchy and very big and exciting.

Sheen: This is the real prize. It is such a surprise to me because I don't see people mention about this. It add some silky sheen to the high ends. It polish the mix in a very pleasant way. None of my previous clones and plugins does this. It makes the other units and plugin sound flat. Dione comes very close because it is also a clean version of the G bus without the THD engaged, but it still doesn't do what the SSL does on the high ends. It really opens up and makes the mix sounds like a record very much.

Originally it is really expensive and I would't recommend. However if you can find a used unit like I did, the price tag is acceptable.
To be honest the clones did very good job but this time I really think that there is something special about the SSL. I am very happy with it and I think I can finally say that my journey of searching for the best bus comp is ended.