First things first. Some folks feel the only proper way to listen to music is in 2 channel. I'll counter that with saying that in life, sound comes to us from all around - bounced off walls and objects around us - we get a sense of our place in the world from those reflected sounds. The recording industry understands this and over the years has provided releases with additional information encoded in the recording for that expanded presence, From the RCA Living Stereo 3 channel recordings on the mid-50s,through the Quadraphonic recordings of the 70s, and the multichannel techniques of newer technologies such as DVD-A and SACD, all wrap us in music I've tried a number of those releases but it can get pricy buying additional copies of music you already own, and sometimes the newer remasters suffer or don't sound the same as the recordings you've had along. The AK mods had read some of my posts on pushing my surround system further forward over the last few years, and offered me a chance to review the new Surround Master from Involve Audio. They told me the Surround Master takes regular 2 channel recordings and extracts positional information from those recordings and takes them to 4, 4.1 or 5.1 channel mode. First – Some notes on my gear – my multichannel system can do 7.1 audio, but in 5.1 mode it consist of Integra DTC-9.8 Preamp/Process B&K ST-202 Plus Stereo Amp for the Front mains B&K AV5000 Series II 5 channel amp - (Center, Sides and rear Surround). Vandersteen 2CE front mains Vandersteen VCC-1 Center speaker DCM TimeFrame TF-600 Rear Surrounds Harman Kardon Citation 22 amp, Bridged Mono for sub JBL 4641 Subwoofer I have a large collection of music in lossless form loaded on a Mac Pro computer upstairs in my office - and I can stream it via wifi to an Airport Express unit on my downstairs system, usually directly to the AUX input on a pair of stereo RCA cables. For this test I am running that 2 channel feed into the Surround Master, and running its multichannel output to the Integra DTC-9.8 preamp. I run the system flat, with no tone controls, no EQ and no spatial effects on the Integra. Source and volume control is all I use. The Surround master comes with a 12 page manual in english (other languages available on their website), 2 3 wire RCA interconnects, and a wallwart power supply with 4 twist and lock adapters to match wall sockets in various countries. I read in the manual and that the unit did 4 channel mode, so we ran it that way for a few days, and while we enjoyed the way that sounded, the manual also says it does 5.1 mode. Since I figure most folks have a surround system set up for 5.1 mode, I switched the RCA cables around, on the rear of the unit to connect it to the Integra preamp's RCA connectors for 5.1 mode. The manual shows 5.1 as front mains, center, rears, and Sub - so that is how we used it for our testing. For that reason, I did not use my side channel speakers for this test. I enjoy all kinds of music and folks here have no doubt heard me say "Its all about the music" - well, the Surrround Master is nothing short of amazing. Listening to music with the Surround master in place really engages you with the music – its immersion – like swimming in the music. It took me a while to write this review because once I heard some of my music through this gear, I wanted to go through my whole music collection and listen to everything again, hearing nuances and subtleties in the music I had not noticed before. Its really like that, like putting a great new pair of speakers or a new amp in your system. I didn't know what to play? Should I try newer recordings, old music, only classics that were well recorded?? I wound up jumping all over the place – and although I played a lot of albums in full, here are some of the tracks that really impressed me: Dusty Springfield in Memphis - Son of a Preacher Man - wow - for a 1969 recording, it was amazing - she's front & center with you, horns and gospel choir behind you. For another older cut, I popped on The Guess Who's Greatest Hits & played American Woman - the quieter intro section was nice, but when the main theme that everybody knows from hit radio way back when kicked in - a great, room filling rhythm sound - the guest we had at the time was REALLY impressed - and so was I! James Brown - 1971 Live at the Olympia, Paris: Love, Peace, Power - A classic lineup of James Brown in concert - this one features an early Bootsy Collins on bass - track 14 - Super Bad - James is front and center, Bootsy's funky bass Jump to Funkadelic Cd – Maggotbrain – the title track Maggotbrain is a psychofunk classic – guitar wailing in and out from different parts of the room Grabbed some older jazz – Dexter Gordon – Ballads, & Miles Davis – In a Silent Way, not quite the revelation some of the newer recordings are. But still a nice listen. Shifting the mood, I chose John Hammond's album of Tom Waits songs - "Wicked Grin" - track #1 is Heartattack and Vine - big thumpin' fun all around me! Then to Tom Waits himself - Swordfishtrombone – title track has vibes behind you, with Tom front & center. Then, from The Mule Variations, the creepy “What’s He Building” has all kinds of ambient atmospheric sounds around you – I nearly jumped when the pipe fitting dropped behind me on the left! Next - Hugh Laurie (House, M.D.) CD - "Let Them Talk" is a great steaming pot full of rhythm and blues I played track 1 - St James Infirmary, and then #12 - Whinin' Boy Blues – great stuff and more immersion within the band space. For another take on that song, I grabbed Hot Tuna's 1st album and played #1 – Whinin’ Boy Blues - followed by #10 - Mann's Fate very quick guitar picking Very compelling – excellent sound from that early trio. Jumping to something older, since we've been talking about James Bond movies on AK, for a hoot, I put on the Casino Royale Official Soundtrack - hey, kitsche can be fun too! Track 1 - Casino Royale Theme by Herb Alpert and the Tijuana Brass - The band is in the rear of the room, Herb's blowing away in the front of the room. Nice! The Highwaymen - Track 1 - Highwayman - its old but fun - Johnny Cash as a Starship captain always get a smile - very great sound filling the room. The Rolling Stones - Sticky Fingers - Brown Sugar,(of course), Wild Horses, You Got to Move, and Moonlight mile - the band is in the back, Mick's front and center, other instruments placed around the room woah - this is great ... played a LOT of this album. All of the Stones I played had similar mix – band behind you, Mick in front More classics – Santana Abraxas – Black Magic Woman – Conga drums behind Carlos’s guitar out front, brushes washing over the front right Jethro Tull 40th Anniversary CD of Aqualung – Locomotive Breathe – opens behind you- when the volume swells the band swells forward to envelope you, with Ian front and center. Pulled some Zappa – very nice immersion in the older recordings - from Hot Rats – Peaches en Regalia , from the Waka/Jawaka – Big Swifty , dabbled in The Grand Wazoo All nice, but I went for broke with the posthumous WAZOO Live album – that’s got some astonishing positioning of instruments around the room – wow! I could go on and on and namedrop more albums I’ve heard hundreds of times that just opened up for me, connecting me so much deeper with the music and tempting me to spend more time immersed in music I had only listened to before. I had a Yamaha Surround receiver with all kinds of room modes that added echo and ambience, my Integra has similar settings for concert hall and beer garden and small club – I’ve tried them and just didn’t care for them, and turned those effects off pretty quickly. The Surround Master is different and really brings you into the music in a new way. All in all, I’d say highly recommended - with any luck, its staying in my system for keeps! That’s how much we’ve enjoyed it! Oh, one last note - the manufacturer says its not just for music - feed it 2 channel audio from your TV or movies or whatever and it will expand them into surround mode as well. I couldn't try that with my system as all my video sources are either HDMI or optical feeds.