ONLY THE RACK IS INCLUDED WITH THE SALE, NOT THE MODULES - 500R8 is the centrepiece to the modern studio. It's a 28-in/30-out USB audio interface that combines a 500 series rack and high-performance A/D-D/A conversion with all of the connectivity required in the modern professional or home studio. 500R8 features the studio essentials that you need to build your dream studio such as an 8-into-2 high-headroom analogue summing mixer, comprehensive monitor controller with talkback facilities, 16-in/16-out ADAT interface, as well as a zero-latency analogue artist mixer with reference-quality, high-powered headphone outputs. The Best Of Analogue By capitalising on the vast and ever growing 500 series market, you can configure your 500R8 to suit your tastes of analogue flavour. By installing your favourite 500 series modules into the 8 available 500 series slots, you can create your ultimate analogue front-end/preamp stage that can be multi-track recorded directly into your DAW. Fill 500R8 full of vintage preamps for recording drums. Fill 500R8 full of clean and pristine preamps for recording strings. Fill 500R8 full of Preamp, EQ, and Compressor modules to create your own custom, analogue channel strips. The possibilities are endless and every 500R8 is unique to your sound. Integrating 500 series modules into your workflow doesn't stop after the recording. Dedicated module source switches for each 500 series slot allow you to send USB channels from your DAW, into 500R8, through the 8 installed 500 series modules. This thing is so versatile it blows the mind. Great summing mixer amazing conversion, tons of I/O & not only that, it's original basic design - a 500 series rack. It's got enough power per slot to power even the most power hungry of modules. If you really want a good overview of what this can do watch Edgetone studios series of videos on You Tube. This guy has thought of every scenerio & way to use this thing!! - I am only selling because I bought an old vintage 80's Ramsa console & don't really need the summing mixer anymore & have switched up interfaces to Antelope audio. Needed even more I/O but this thing has served me well even though I only just bought it this winter & really only touched 1/10th of what it can really do!! Now it does have the usual racking rash you get from inserting into & out of racks as I was setting up a new studio & getting new racks & having growing pains from not having enough rack space. (Is there ever enough). I will say they do take up 4 rack spaces because of the summing mixer at the bottom. I had the Cranborne 500 ADAT as well & that's 8 RU right there!! But with that unit & this together you get 16 channels of summing & module space!! Also the Speakers A/B light flickers a little bit but the price more than reflects those imperfections.