Involve Audio Reviews

The following reviews were unsolicited and are the opinions of the reviewers. Involve Audio wishes to thank our past and future reviewers for their honest and unbiased opinions.

1Involve Audio Surround Master Review by StereoNET
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Written February 24, 2015 by Simon Tremlett

Surround sound has been in homes for many years. From the first “quadraphonic matrix” systems in the 60’s and 70’s, to the current fully discreet 7.1 channel systems.

There were, of course, older examples of surround sound used in movie theatres, and the newest home theatre amplifiers have decoding of up to 11 surround channels (plus LFE/Subwoofer), but the digital standard is still a maximum of 8 discrete channels. Over the years, there have been many different ways to “encode” those surround channels into a stereo signal, so that “normal” people, without fancy home systems, can also enjoy the music on their stereo HiFi systems.

Decoding these extra sounds and delivering them to your surround system has often been a case of “choose your poison”, with none of the specialised equipment for decoding one system being able to reproduce another’s with any great results.

Enter; the ‘Surround Master’ from Involve Audio. This little piece of kit claims to be able to decode pretty much any type of stereo-encoded surround sound, into 2.0, 4.0, 4.1, 5.0 or 5.1 discrete channels of surround sound audio. How can you decode stereo into 2 channels of surround sound? That’s what I asked myself. Time to hook this thing up and give it a try.

n the box you get the Surround Master unit, a brief instruction manual, a 9V DC multi-plug power adapter, and enough RCA cables to connect the unit from a 2-channel input to 5.1 channel output. The unit itself is a simple black plastic case with raised “chrome” lettering; rather light weight. I needed to know more before undertaking this review, and being sceptical in it’s ability to convey good sound, other reviews online told me otherwise. Not being someone easily swayed by others’ opinions, I had get this thing going to test all the different claims from the makers.

Connection to my vintage Pioneer VSX-AX1 surround amplifier was quite simple using the 5.1 channel discrete inputs, as illustrated in the Surround Master’s instruction book. For the music source, I used my current micro-hifi system – a Sony CMT-SWB300WB, via the headphone output – for USB, WiFi Streaming and DAB+ playback. A Pioneer PD-6500 will serve as the CD player for this test. With the Surround Master switched off in its default pass-through mode, I confirmed the correct connection of all the speakers and set the level from the Sony unit to match the maximum input for the Pioneer CD player and amplifier. Set to 2-channel mode, I held my breath and flicked on the Surround Master’s power switch.”

I was not disappointed. My first impression of the Surround Master was that the expansion of the stereo image was nice – not subtle at all, but not overpowering either. The centre image vocals in Kate Bush’s“Army Dreamers” was still rock-solid in the center of the sound stage. The ambience and incidental vocals seemed to project to the width of the room, and the stage depth suddenly extended an extra metre or so further back into the wall. Interestingly, there was no change in loudness or dynamics, just a bigger sound stage. On closer listening, comparison between the original pass-through and TSS (Two Speaker Surround) mode, there was a slight but noticeable emphasis in the mid-range sounds of the ambient signals compared to the 2-channel original – but not in any immediately unpleasing way. On to the full surround decoding.

In 4-channel mode, I flipped through some older Quadraphonic, Matrix, and CD-4 Stereo encoded recordings of Pink Floyd, Uriah Heep, and Credence Clearwater Revival. The recording quality of the tracks I played varied quite a lot, but generally, the full 4-channel sound was reproduced with the quality of the decoder results varying according to the overall quality of the tracks. One thing I did notice, if the source isn’t almost immaculate in its own quality, the decoder really has trouble discerning the front/rear separation – and in some cases it was just wrong to my ears. On to a Dolby Pro-Logic encoded source … wow, I was amazed at the clarity and dynamics again – this was an excellent source. The Chesky Records “Gold Stereo and Surround Sound Set-Up disc” – the Left/Right and Front/Rear decoding was almost seamless, and certainly without any noticeable artefacts, wobbling of the surround images, or funny phasing of the bass signals which can be apparent in a poor quality decoder.

At $499.99 RRP, the Involve Audio Surround Master is a must-have for those audiophiles with a broken Sansui or Technics surround amplifier from the 60’s and 70’s, or for someone who wants to know what early surround sound was really like. There’s still a lot of LPs and CDs around with Quad encoding from the original master, and you just won’t get the surround sound from these without the Surround Master decoder.

For more information visit Involve Audio.

Posted in: Hi-Fi Home Theater Technology
2Involve Audio Surround Master SM-465 by Gadget Review
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Written May 21, 2013 by Marshal Rosenthal

I still remember when Dolby sent me their first “surround sound” processor back in the 1980’s. They said that their processor could “extract” ambient sound from within a recording to create a wider sound-field. And that it didn’t matter what the audio source was as this “added” sound was always recorded along with what was “heard” — which was a stereo recording. Of course today there’s discrete 5.1, 7.1 or even greater numbers of audio streams that can be processed through multi-channel receivers, but what about all those recordings that never made it past stereo? Rather than being forced to use psycho-acoustic sound techniques to “fool” your ear, plug in the Surround Master.

Here’s what it’s does: process an evenly distributed sound-field that envelops you (immersive); create distinct points of audio (think: a bullet traveling from in front of you past your left shoulder); recreate the original audio so that the listener doesn’t feel there’s some kind of techno-babble going on (i.e., you may hear explosions at your side, but John McLane’s “Yippe-kiya” is as distinct as if listening to Die Hard on an iPod).

Surround Master is about the length of a mini DVD player and about half as wide. Plug the AC plug in for ongoing power last — first set the switch on the front to 2-channel mode. Then attach a pair of RCA stereo cables into the outputs from your audio source and the other end into the 2-channel input. The last step is to connect RCA plugs from the 2-channel output and into the Aux of an amplifier. If you decide to go with 4 speakers, then the switch goes to 4-channel mode and the Left Front/Right Front, Left Rear/Right Rear outputs are used, with their other ends plugged into the appropriate places on the amp. Use of the subwoofer is optional in either case.

Nothing special has to be done to the amp, with the exception that all surround sound simulated modes (like Dolby Pro Logic) have to be turned off so that the sound exiting to the speakers is not being modified (most amps call this “Direct Mode”).

Involve audio who makes Sound Master recommends using the 4-channel mode, so I’ve set it up that way. I’ve a pair of stereo speakers in front of me and a pair to the side and behind (what would normally be called “rear” speakers). My position is at the center so that each speaker’s bulls-eye is my body.

I’ve been given a demo disc to use in which specific scenes are produced that display surround effects. I played the disc first as stereo and verified that the scenes I would use as “test subjects” are just in stereo. Frequency response and other measurements were obviated in favor of my ear — if what I heard sounded right, then I was going to be happy. So I began the test:

* Transformers: Battle sounds come at the listener from multiple locations, not just the front, which was the case when played without the Sound Master. A rocket fired at the end of the sequence “travelled” from the front speakers to the back and was clearly perceived a such — again this did not occur when the scene was played as ordinary stereo.

*Dummyhead Stereo: Both a rear and side sound-field could be clearly heard, but more importantly it was a clean performance that didn’t get “mushed” together (flutes being played demonstrated this fact).

*X-Men: The sequence had Professor Xavier using his mind powers on Wolverine to cause voices to “rotate” around the listener’s head. There was a clear perception of this happening, as opposed to the audio remaining fixed at the front when it was played in stereo. Additionally, the dialogue was not muddied or had any hiss or interference to signify some form of audio modification was in process.

I also tried out the Sound Master with a number of symphonic CDs and videocassette commercial movies. The surround sound on the CDs varied in intensity, in some cases being extremely mild, but at no time did I encounter any degradation in the audio. As to the movies, surround sound effects that were clearly not present when played normally were now evident.

Switching over to the 2-channel mode creates a “virtual surround” effect that functions without such tricks as bouncing audio streams off walls. I’ve never been impressed by any of the modification technologies used to do this and the experience relies heavily on the perception of the person listening. I can say that the Sound Master performs as well as any other technology in this mode and many will find it an appealing way to enhance their sound-field. But used only in this manner is a waste of what it can do.

Overview Release Date: Available Now Price: $395 Model #: SM-465 Article Type: Review Brand: Involve Audio Type: Sound Processor Positives Tech-free setup, Multi-country power supply Negatives Requires 4 speaker setup to be truly effective Bottom Line When used in a 4 speaker system, the Sound Master accurately reproduces the audio you expect to hear, but then adds in what was hidden to produce a surround sound-field. The actual process doesn’t care what the stereo audio source is — the sound cues that have been recorded are brought out and given a distinct “location” in space relative to where they were during the recording. The results are superior to that of existing psycho-acoustic surround sound effects and more than justifies the $395 price tag for those who wish to have multi-channel sound for as much audio content as possible.
3Surround Master Processor by Audiophile Audition Web Magazine
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Published on May 6, 2013

First of all, these Australians—some of whom were involved with Lake and other Aussie companies specializing in surround sound and acoustic effects—have come up with a really successful pseudo-surround processor for two-channel sources. It is much more effective and less gimmicky than either Dolby Pro Logic IIx or Circle Surround. In fact, it is similar to the Circle Surround processor which I used to have in my old car, in that it even creates some surround effect from mono sources as well as stereo sources.

All stereo recordings have L-R or “difference” information which this type of pseudo-surround processor uses to pull out the out-of-phase information which can then be directed to the surround channels. This differentiates them from the “hall,” “jazz club” and similar processors in most multichannel preamps and receivers, which only add artificial reverb and EQ to the signal and are nearly always ineffective and unnatural-sounding. Today we have many different surround sound processes: the discrete three-to-six-channel systems of SACDs and DVD-Audio, the lossless multichannel systems of Blu-rays, the lossy systems of DVDs, and even some processes for Net downloads in surround. Then there are the analog two-channel surround codecs of Dolby Surround and Circle Surround which are pretty much obsolete by now.

There are audiophiles who play all their music-only sources as only stereo via their front left and right speakers, using their surround systems strictly for playback of movie soundtracks with that feature. As our readers are probably aware, AUDIOPHILE AUDITION supports Surround Sound for Music, and believes that since sound comes to us from all around us, listening to music in surround makes a lot of sense. The Surround Master makes it possible to achieve a very convincing surround effect from any stereo source with just four speakers and amps, and without any investment in discrete audio playback or specialized recordings.

The Surround Master is powered by a 9-volt wall wart and comes with a clear 12-page manual in English. The connection cables are included. It has only an on-off switch and another on the front which can be set for either 2-channel or 4-channel. (You must switch it on before you power on your amps; otherwise it creates a loud pop.) The 2-channel setup—which I did not test—creates a semi-surround effect from any stereo sources with just two speakers in front (probably similar to some of the soundbars). The 4-channel setup is specialized for playback via four similar speakers equidistant from the listener, and an optional subwoofer if you wish. However, since many users will have a 5.1 surround speaker setup already in place, it will also work with a center channel, and also with the two surround speakers placed more to the sides rather than directly behind the listener. Involve feels there is really no need for a center speaker nor additional rear speakers of a typical 7.1 setup (and I agree on the latter).

The Surround Master comes with a demo DVD which has two repeats of sections from various action movies, and encourages the listener to play the first one without the Surround Master in the circuit (or set to 2-channel) and then use it in the 4-channel mode for the second repeat. It includes on-screen moving images from their “vectorscope” which shows the sounds you are hearing in visual form, using various processes in comparison to the Surround Master. I must say, the Surround Master processing often creates a surround field even superior to many DTS-HD MA 5.1 tracks. Some of the images are very interesting, such as the ProLogic II one showing no surround signal at all, which I don’t agree with—although Surround Master is much better, with less emphasis on the center channel.

The big problem here is that there is no way to switch the Surround Master in and out of one’s system for comparisons and to properly play actual 5.0 or 5.1-channel sources. One must disconnect the cables for channels 3, 4 & 5 plus the subwoofer from your preamp or receiver and reconnect them directly to the rear of the Surround Master. Its two-channel input signal must come from the two-channel outputs on your preamp or receiver; you cannot feed it multichannel signals. (The Involve tech person was concerned that I might not be getting the center channel signal into the Surround Master—even though I had selected “Multichannel Mix-Down to Stereo” in my Integra preamp. He advised me to move the two-channel feed to directly from my Oppo deck; an odd piece of advice since that meant no volume control whatever. Once my hearing returned I went back to the output from my Integra preamp.)

I do have level controls on the amplifier connected to my surround speakers, and there is a main level control on the Integra preamp for the two-channel feed. However, without the preamp there is no level control for the center channel, which goes directly to a tube monoblock amp. Therefore it is extremely difficult to set balanced levels on all the speakers when using the Surround Master. No matter how I set the levels of the left and right front speakers, the Surround Master seemed to provide more of a frontal signal on the left side and more of a rearward signal on the right side. Not only was I unable to use my side-height speaker feeds, but I could only audition all my multichannel SACDs as two-channel sources. I had to change the option on my Oppo deck from multichannel to stereo only.

However, the surround field from most two-channel sources was phenomenal. Many 5.0-channel SACDs have extremely subtle surround channels, which often have to raised in level to create more of a surround field. I never had that feeling from playing two-channel sources thru the Surround Master. Not only was there an excellent surround signal extracted from the original, but there was a more seamless surround field to the sides than achieved with most multichannel sources, even with my surround speakers to the rear. Occasionally there were instruments very specifically located at various points between the left front speaker and the left surround, and vice versa. There were not any artifacts or unusual equalization of the sound at any point. It appears that the higher the resolution of the stereo source (such as 2-channel SACD or 96K/24-bit) the more difference information the Surround Master processing has to work with and the more convincing the surround field it creates. (There are also some superb discrete 5.0-channel SACDs which capture the acoustics of the concert hall or performance venue with startling realism.)

In addition to providing a much better surround field (using the stereo layer) from those multichannel SACDs lacking a sufficient signal on the surrounds, the Surround Master created terrific sound fields from older 2-channel Dolby Surround CDs, UHJ Ambisonic CDs and LPs, and Circle Surround CDs. Sometimes I even had to turn down the level on the surround speakers for an improved balance. Then there are many stereo-only pop and jazz SACD reissues and even some mono SACDs, which would create a surround field, rather than be restricted to only the front left and right speakers, as when playing in normal SACD mode. (Most preamps unfortunately don’t allow using Pro Logic on the discrete stereo SACD sources.) If you’ve already discovered the terrific surround placement you can achieve with the standard stereo releases of the Beatles and Beach Boys using Pro Logic IIx, you’re in for a real treat with the stepped-up spatial positioning of the Surround Master.

If I were an independent audio buff without the magazine connection, I think I might even consider purchasing (probably used) one of those stereo-only high end SACD decks from Denon and others, set up four identical full range high-quality speakers and use the Surround Master to create the surround field from all two-channel recordings, both standard and hi-res.

Involve is to be commended for keeping the price reasonable for such a convincing surround experience. But meanwhile I will await a future model of the Surround Master that will allow for proper integration into an already-existing discrete surround system, as well as replacing and allowing comparison with Dolby Pro Logic II using stereo sources.

—John Sunier
4Surround Master from Audiokarma Web Magazine/ Forum
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Reviewer: Heather James Join Date: Mar 2007

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.

5Surround Master from Roy Morris
Hi David,

Having just received an email from your company to confirm my order is complete, reminded me I hadn’t given you any feedback on your fantastic product.

What can I say… I have a totally new CD collection, and stereo television soundtracks come amazingly to life, surrounding me with such detail never heard before! The sound is so immersive when fed through the Surround Master it is uncanny! I won’t even try to understand the technology, but the result is terrific, putting the listener right in the middle of the action!

I have had the pleasure in the past of being in music studios during recording sessions, and audio through the Surround Master gives me that same ‘hairs standing up on the back of the neck’ feeling…. Well done!

My only regret is that my family won’t let me play my audio at anything like full volume. I’m going to have to move to a much bigger house now!

Best regards, Roy
6Surround Master from Klaus Hönemann
Hi David,

I set a link from my homepage to your homepage and a little review. In 2013 we tested the Surround Master by Dietrich Räsch’s quad system in Hamburg.

The Surround Master against Fosgate’s Tate II in SQ and against Sansui’s QSD1 in Surround. The Surround Master wins both tests. There is a little review of this test on my site.

Best regards, Klaus Hönemann…h_rasch-1.html
7Surround Master forum review compilation 2002-2015
A PDF document containing a compilation of all the reviews on the Surround Master up to June 2015 – Click Here (PDF)