December 2012

Audio Space Reference 3 Monoblock Amplifiers
Tube power to rock your world!
Review By Anthony Nicosia

  Audio Space is a Hong Kong company distributed in the US by Gini Systems of Pomona California. They not only make a large variety of tube amplifiers but also a CD player, loudspeakers, a subwoofer, phono stage, and preamplifier. In fact their Reference 2 300B tube true balanced preamplifier has been getting rave reviews worldwide and would appear to be a worthy consideration for use with the Reference 3 amplifiers up for review today. My first experience with an Audio Space product occurred close to two years ago by way of a friend returning from a visit to China. While there he purchased a Houston integrated tube amplifier which had been converted to 120V making it usable in the United States. Now you see Houston audio products are a sub division of Audio Space, hence the connection. That little amplifier used four EL34 power and four small nine pin preamplifier tubes while putting out around 20 watts into an eight ohm load. The sound was so impressive that I purchased that particular unit from him immediately upon auditioning it. Unfortunately, like a lot of gear I have previously owned it was sold and replaced by the newest toy to catch my interest rather than any lack of faith in the product itself. Today’s review of the Reference 3 mono blocks are about an altogether different breed of Audio Space product in that it is farther up the audio chain than was that Houston amplifier of two years ago. For what you get at $7900 a pair it definitely falls under the "bang for the buck" category of high end audio gear as you shall shortly discover.

Technical Details
The Reference 3 is a 26-watt per channel Single-Ended Triode amplifier operating in Class A. I sent off asking for some technical information not found on the web site and the following details were given me by Audio Space via Gini Systems their United States Distributor.

"Each Reference 3 mono block uses a 6SL7 small signal triode tube in the front end, parlayed into the 300B driver tube. The 6SN7 triode tube serves as a buffer between the driver stage and the 845 output stage. Both 300B and 845 tubes are top shelf OEM tubes that have been thoroughly tested in accordance with stringent Audio Space's design quality standards and branded with the Audio Space label. The capacitors in the Reference 3 are specially selected to accentuate the design goal of the amplifier. High end Jensen copper foil capacitors are used in the front-end and buffer stages to shape the sonic characteristics desired, while German Zero Cap high output voltage capacitors are used with the 845 tube to achieve the desired output performance. Transformers and inducting coils on all Audio Space products are designed and manufactured by Audio Space in house where the amplifiers are also manufactured and tested. All transformers are hand-wound and made with proprietary methodology and material."

They came well packed with each of their four tubes already inserted in their respective tube sockets. Not to worry though as the tubes were surrounded with ample packing material in order to avoid breakage during shipping. All the transformers, chokes, etc., were partially wrapped with material designed to be removed prior to turning on the amplifiers, a relatively simple process really. As for the tubes please be careful and note that if the need arises the 300B tubes in particular must be inserted the correct way. They have two thicker and two thinner pins and forcing them incorrectly into the sockets, large pin in small hole, could damage the amplifier. That of course is true with any 300B tube whether used with this amplifier or another. Placement of the Reference 3's on the floor was quite simple. With four spiked feet preinstalled one need only place each amplifier on the four factory supplied discs, or without if you so choose. I used those discs as the amplifiers were laid to rest on my wife’s precious hardwood floors and not a carpeted surface.

Each amplifier was placed in close proximity to its respective loudspeaker and looked great sitting there openly displayed. Those factory supplied cones stopped each of those seventy-two pound amplifiers from pushing their spiked feet into the wood surface and damaging the floors, always a good thing. Both Reference 3’s came with one 845, 300B, 6SL7 and 6SN7 tube placed in the front of each amplifier. Located behind them was a very large output transformer sitting next to two choke coils, a very large power supply transformer and three good sized capacitors. The attractive front panel with its brushed aluminum faceplate sports a power on/off knob, switches for feedback adjustment, meter range, rear panel input selections (Balanced or RCA) as well an input source switch. There is a volume control knob off to the right side and in the center a large meter for adjusting Bias or to display output signal level depending on how you set the controls. The back panel has inputs for either XLR or RCA cables as well as loudspeaker connections of 4, 8 or 16 Ohms. Factory supplied power cords are provided but I would think that like me most will wind up using their own aftermarket cords to plug into the IEC outlet. For the purpose of this review XLR cables by Monarchy Audio were used to connect preamplifier to amplifier and later from a direct source when put into its integrated amplifier mode. This will be discussed in greater detail later.

Let the Music Play Commence
Figuring the strength of the Reference 3's 845 and 300B tube configuration might just lay in the reproduction of vocals it seemed a good place to start this review would be with a vinyl recording of Cat Stevens Tea for the Tillerman [A & M SP4280]. After all music generated from a combination of a tube amplifier and vinyl records usually leaves me grinning from ear to ear with audiophile delight. Here both vocal content and guitar took on an earthy quality with Cat Stevens leading me down an orderly well laid out musical presentation during "Hard Headed Woman". It was easy to envision this performance unfolding before me as the Reference 3's laid out an appropriately sized soundscape with music and vocals emerging from a silent background. The opening piano sequence from "Sad Lisa" was amazing. Notes from piano hung in the air slowly fading out to display the excellent decaying effects these amplifiers are able to deliver. John Rostein's violin sounded as if his instrument were nearby in my room adding a melancholy mood to this sentimental song from.

As with all good quality systems it is important to put your best foot forward and on the thicker, 120,150,180, and 200 gram records the Reference 3's really strutted their stuff. Here they showcased all that my turntable/cartridge combination could retrieve. By digging deep into the recordings from these high quality vinyl records the 845 power tubes added just the right overall sense of you are there liveliness to each performance. There are so many great songs from Bob Dylan's The Freewheelin' Bob Dylan [Columbia/Sundazed LP 5115] that it was difficult choosing just a few to use as examples. The biting edge to Dylan's voice on "Blowin' In the Wind" reminding me of the sixty's with all its youthful turbulence and hope. The realistic presence of his vocals, three dimensionality of his guitar and truth of timbre to the harmonica on "Girl from the North Country" took my breath away. Not only did the Reference 3's appropriately display imaging within the soundscape but did so with a good sense of warmth as both instruments and vocals were portrayed with true to life heart and soul. Do not take that wrong, the tube warmth was quite appropriate and not in overabundance lacking in focus or detail. Source material had a good sense of presence sounding true to live music as great amplifiers tend to sound. This occurred both on vinyl and CD making each medium sound all the better when heard back through the Reference 3's.

Night after night passed rather quickly as I became lost in musical bliss without ever feeling the need to take any type of a break. In fact it became necessary to watch the clock as the hours swiftly flew by without a thought to their passing. These amplifiers took a bit of the edge off of Bob Dylan's vocal presentation making it a tad more pleasurable to hear. With "A Hard Rain's A-Gonna Fall" there were moments when he would normally sound a bit shrill but these amplifiers from Audio Space helped yield a sound more pleasing to these ears. The Reference 3's especially gave my CD collection a little added boost as its tubes took the edge off this somewhat harsher musical medium. Easing the transition from vinyl to cd came via Michael Buble’s It's Time [143 Records/Reprise]. This is a great recording that would be nice to have had on vinyl. "Foggy Day" had musicians imaging on a very clearly defined soundscape with each easily identifiable. Bass, drums, guitar, percussion and that oh so wonderful voice were each given their own space within which to shine. Michael Buble’s vocal presence definitely came alive with the addition of the Reference 3's to my reference system. Closing my eyes to imagine myself in an intimate setting, perhaps a small club somewhere off Broadway, was very easy with the aide of those lushes 845 power tubes.

On "You Don't Know Me" their ability to exhibit a proper decay of vocal and piano notes created a magical moment in my room. The duet with Nelly Furtado along with the accompanying saxophone solo was out of this world good. Their performance was intimate, realistic, spatially well-defined and with a proper amount of detail. The Reference 3’s did well with Cat Stevens, Bob Dylan and Michael Buble but now it was the time to see how they would fare with Rock and Roll or large Orchestra music. On Carlos Santana’s Supernatural CD [07822 19080-2 Arista] there were plenty of percussion, congas and drums all on the same stage together. The question was how they would handle this large mix of performers playing simultaneously. Actually these twenty-six watt tube amplifiers fared very well, much better than anticipated with my medium efficient Von Schweikert VR-35 loudspeakers. Here on "Da Le Taleo" a large soundscape full of talented musicians unfolded before me to display images both clear and distinct. Tube amplifiers of lesser quality might come across slow and plodding lacking in precise imaging, not so with the Reference 3's. They handled the many musicians onstage as well as the lightning quick guitar work of Carlos Santana with apparent ease. Nice wide soundstages, good three-dimensional imaging, quickness, tube magic, all can be used to describe my time with the 3's.

I particularly like hearing "Maria, Maria" with lead vocals provided by The Product G & B. Not only did they sound realistic but mid-bass definition was strong and distinct. The only place where one need be careful will be in matching the amplifiers power output to appropriate loudspeakers. When playing them through my Martin Logan Sequel II’s it was easy to push them hard enough to hear distortion as the amplifiers hit their limits. Those however are very power hungry loudspeakers and there are many amplifiers that would find them difficult to adequately drive. With the medium efficient Von Schweikert VR-35’s this did not become a problem. In fact they pushed the VR-35’s to levels I felt truly satisfied with. Still it would have been nice to see how well the Reference 3's would have sounded if connected to my Klipsch Klipschorn loudspeakers. They unfortunately are no longer with me having found a new home somewhere in Germany where I envision them playing beautiful music for their new owner.

The Klipschorn’s have a 104dB w/m rating and could rock even when connected to a pair of 4-watt Dignity Audio tube mono block amplifiers. Imagine how they would have sounded with these twenty-six watt "powerhouses" from Audio Space. On the SACD recording of Wolfgang Amadeus Mozart's Requiem in D Minor K626 [BMG 82876 58705 2], Mozart's unfinished masterpiece, the 3's once again shinned. Each singer within the choir was showcased individually within the context of the larger whole. This large scale orchestra work never failed to thrill me with its portrayal of a large wide three-dimensional soundscape. The 3's were powerful enough to fill my medium sized room with the magic of tubes without running out of steam and this great recording became a pleasure to hear. As for timbre presentation of both string and horn sections the 3’s left me with a truly satisfied feeling with regards to each individual instruments. Rather than projecting images of loosely defined bass the 3's did a great job outlining lower and mid bass notes true to the correct musical content on hand at the moment. Listening fatigue never entered the equation as long late night listening sessions were again a pleasure to entertain.

The Reference 3’s As An Integrated Amplifier
Perhaps the biggest choice one must make is whether to use the Reference 3’s as mono block or integrated amplifiers. The beauty of the 3’s is that all one need do is run a source, such as a CD player or phono stage, directly into these amplifiers after just flipping the switch on their front panels from source to direct. Doing so allows for the Reference 3’s to be controlled by their volume control knob located on the right side of their front faceplates and viola, you now have an integrated amplifier. What was personally lost from my system though was the convenience of a remote control but as we all know life has its little tradeoffs. If you need to adjust the balance on individual recordings the two separate volume controls, one on each amplifier, still makes that all possible. The only small glitch is that there are no digital readouts telling you exactly how accurate the balance is. This never proved a problem as long as I carefully looked at the controls matching both accordingly with their faceplate markings.

Running them as integrated amplifiers will not only save you the expense of a separate preamplifier but the associated interconnects and power cords (especially if you use high dollar aftermarket ones as I do). If though your system needs more inputs or you feel you must have a remote control then by all means go with a preamplifier as a remote is just not part of the 3's package. Losing the mute feature was a different matter. If the phone or doorbell rang or a family member called out from another room it was just a matter of hitting the pause button on my CD's remote control to put things on temporary hold. With the turntable though it necessitated getting up to cue the cartridge off the record or if you prefer going over to lower the volume on both mono amplifiers, yes a small inconvenience in exchange for saving a bit of money. This was definitely something I found livable with especially since my vinyl listening sessions are rarely interrupted. Do not let either of these small possible inconveniences make you for even a moment to not consider the 3’s for use as a stand alone unit.

In integrated amplifier mode while re-listening to the same above mentioned Mozart Requiem in D Minor K626 CD I was not able to detect any major differences. The soundscape still appeared wide as well as deep, clarity was constant, music had a feeling of a proper weight to it, and isolating performers was still one of its stronger points. With The Oscar Peterson Trio CD We Get Requests [LIM Records B002HTWYZ6] the focusing ability of the Reference 3’s was startling. This was the best I have heard from this song yet as each performers location was so clearly defined in a very wide soundscape. Dynamics remained intact, to a great extent, as swings from low to high volume were reproduced almost with the same ferocity as with a separate high quality preamplifier in place. All in all if budget constraints warranted I would not hesitate to recommend listening to them as stand-alone integrated amplifiers.

Yes my $5000 preamplifier did take things to a slightly higher level but that difference was ever so slight making me question cost versus need and to wonder if that money could be better put to use elsewhere within my system. It would certainly buy me a great deal more CD and or vinyl recordings, always a big plus. It seemed that only those seeking out the highest degree of musical reproduction would even question the need to look for a separate preamplifier. For me listening without a preamplifier produced no regrets whatsoever. Given my very positive experience with the Reference 3’s it did though spark my interest on how their Reference 2 300B tube preamplifier might have sounded if both were used together. Perhaps that would be a good place to start if one were to opt for using them as mono block rather than integrated amplifiers.

Conclusion
Since I am a believer of looking at the glass being half full rather than half empty let us start by looking at the many positive attributes of the Reference 3 amplifiers. First off they use tubes, four each, and tubes produce those even order harmonics are brain so dearly loves. Secondly the Reference 3's are mono block amplifiers with two larger transformers, one for each unit, instead of one smaller transformer housed within a much smaller single chassis. Doing this helps make for an increase in power during demanding musical passages while keeping the music sounding clearly defined. Let us not also forget the preference for using shorter loudspeaker cables but longer interconnects (preferably XLR cables) as the amplifiers can now be placed one each next to their respected loudspeakers. Thirdly and something not to be overlooked is the fact that these amplifiers are to die for with their attractive faceplates, large output transforms, chokes and capacitors all in plain view. Same goes for those gorgeous 845, 300B, 6SN7 and 6SL7 tubes which should never be hidden behind audio rack doors yet rather displayed in full view for everyone to see. Fourthly, you can adjust feedback on the fly with just a flip of a switch, a great feature to have and one I used during my listening sessions whenever I felt it appropriate. It would be nice to see this feature found on more products. As for biasing those large 845's it was a snap with its built in meter needing only one small screw driver to do the job. Lastly the Reference 3's allow their owner to avoid using a preamplifier when used as two integrated units thusly saving you a substantial amount of money in the process.

On my very short list of concerns it can be said they produce only 26-watts of tube power and so must be carefully matched to appropriate loudspeakers as well as the size of your listening environment. Not having 450-watts of power like my reference amplifier it took a little while to get used to. Once I settled in to appreciate their sonic capabilities of imaging, layering of musicians in a deep front to back soundscape, delicacy, presence and focus the 3’s won me over big time. With the proper setup you can sit back to "Enjoy the Music" while the Reference 3's perform in admirable fashion. Without question these amplifiers from Audio Space are not only long on quality but a monetary bargain to boot. Save your money, use them as integrated amplifiers, run XLR cables long, keeping loudspeaker cabling short, then turn out the lights to enjoy not only the sound but the beauty of those 845 tubes glowing in the dark. Life is good and so are these amazing tube amplifiers from Audio Space, give then a listen.

The Listening Environment
The review room is eighteen feet eight inches long by thirteen feet wide with loudspeakers and equipment kept on the short wall. The cathedral ceiling starts at eight feet from the short wall slopping upwards to reach a height of thirteen feet in the middle than returning to eight feet at the opposite end. The hardwood floor is partially covered by a nine by six foot oriental rug lying down the long ways facing toward the loudspeakers, placed dead center between but not under the listener or the audio system. The room has no doors but there are two openings. One opening is in front of the right loudspeaker giving access to the hallway while the other is behind the listener’s position opening to a formal dining area. There are three large floor standing acoustical panels and numerous Auralex Studiofoam panels placed around the room as well as three GIF Tri-traps one in each of three corners. All the audio equipment is located in a Synergy Twin S30 Salamander audio rack placed about a foot away from and in the middle of the short wall opposite the listening position. Power conditioners are located on the hardwood floor behind and to the left of the audio rack with the exception of an Audience Ar2p-T0 which is plugged directly into the socket behind the rack.

Review Equipment
Von Schweikert VR-35 Export Deluxe Loudspeakers
Aesthetix Saturn Calypso Preamplifier
OPPO Digital BDP-95 Universal player
Oracle Delphi MK 1 Turntable, Grace 707 Tone arm with custom made
interconnects
Audio-Technica Prestige AT33PTG Moving Coil Cartridge
Whest Phono Stage & .20+MsU.20 Power Supply
VPI 16.5 Record Cleaning Machine
Acoustic Revive RPT-4 Ultimate Power Supply Box
Audience: Ar2p-T0 power conditioner
Loudspeaker Cables: Kimber Kable 4TC and 4PR (bi-wired to loudspeakers,
top and bottom respectfully)
Interconnects: Monarchy Audio DAB-1 XLR Balanced cables
            Acoustic Revive XLR Balanced cables
Power Cords: Tek Line PC-8 Signature Power Cords (2)
            Mr-Cable Musician Power Cord
            Monarchy Audio AC-1 Power Cord
            Acoustic Revive Power Cords (2)
Cherry Synergy Twin S30 Salamander audio rack

Specifications
Type: Monoblock vacuum tube amplifier
Operation Mode: Single-Eeded triode
Output Power: 26 W/ch Clas -A
Output Impedance: 4, 8, 16 POhms
Input Sensitivity: 300 to 600mV
Input Impedance: 60 kOhm
SNR: >87dB (hum noise < 1mV)
T.H.D.: <1%
Input: unbalanced via RCA and balanced via XRL
Tube Complement: One each 300B, 845, 6SN7 and 6SL7.
Size: 20.5" x 14.5" x 9" (DxWxH)
Weight: 72 lbs each
Warranty: Two years parts and labor on electronics (90-days on tubes)
Price: $7900 per pair

Company Information
Audio Space
1F, 151 Apliu Street
Sham Shui Po
Kowloon, Hong Kong

Voice: (852) 2729 7271
Website: www.AudioSpace.com.hk

United States Distributor
GINI System, LLC.
3431 Pomona Blvd., Unit G
Pomona, CA 91768

Voice: (909) 720-8188
Website: www.Gini.com