Before I get started on my experience, here’s an outline of the equipment used, why I have been interested in the AKSA, and my objectives for the audition.
Source: Panasonic XR50 CD/DVD transport, Musical Fidelity TriVista 21 DAC
Line-level: Musical Fidelity A3cr, dbx 223 active crossover
Amplification: Carver PM-175, AKSA 100N+
Speakers: Anthony Gallo Reference 3, DCM Timeframe TF400
Interconnects: DIY Cardas/Belden 89207, misc Monster coaxials
Speaker cables: DIY Jon Risch CC89259, 14AWG stranded zip cord, DIY Cat 5
I have auditioned the Gallos with the Acurus A250 and the Simaudio i5 integrated, but they were not available for direct comparison with the AKSA.
All the critical listening recounted herein is via the XR50/TriVista combination, but I often use an HTPC with ASIO (bit-perfect) output via S/PDIF into the DAC.
I have never been a tube amp owner, although I do appreciate the sonics of tube designs WAY beyond financial consideration. I want to be able to sit down and just listen to quality music, watch TV or play a DVD without worrying about the time on the tubes, etc. The marketed qualities of the AKSA appeal to me here.
My objectives for the audition were to: evaluate the musical performance of the AKSA amplifier, and experiment with the Gallos’ pseudo-biamping features. These speakers have a dual voice coil woofer, with one coil connected to the full-range speaker inputs, and the second to a dedicated sub input. There is no way to split off the first voice coil from the rest of the speaker without modifying it. Thus, the AKSA always was asked to provide power to the woofer’s primary voice coil.
My review methodology was to simply listen to recordings which I have heard tens, if not hundreds of times, and write down anything that truly struck me as exceptional, remarkable or different than previous experiences.
First, some general observations:
It was interesting (and disconcerting) to discover how many recordings have serious mixing and production flaws, that I thought were flawless. The AKSA ruthlessly revealed any anomalies, and faithfully rendered recorded hiss to a very noticeable level, where it had been forgotten or ignored before.
The Gallos have been reported to be slightly soft in the lower midrange, which I have validated with several amplifiers, most obvious in male vocal recordings. I think that this may be partially a break-in issue, partially a speaker placement/phasing issue, and that people are used to popular speakers that have a characteristic bulge in their midranges. In any case, the AKSA immediately erased my historical impressions of the Gallo lower-midrange. Perhaps it is just a fortuitous combination of amp and speaker, but the male vocals were full and vibrant, and I honestly didn’t think about it again after that minor revelation. Hugh, should you be able to convince Srajan Ebaen to audition the AKSA, his feedback will be an interesting read. He is a Gallo owner and has postulated on the configuration options and challenges of the speakers.
Someone commented on the AKSA throwing a wide, but not deep soundstage. IMHO, the soundstage is uniquely dependent upon the combination of amp, speaker and speaker/room configuration. Therefore, the likelihood of different system combinations offering divergent results is high. My result? The AKSA’s soundstage width was not dramatically different than the Carver. Depth, however, was palpably increased, especially at higher volume levels, and the amp’s ability to create the ambience of recording venues was excellent. I imagine that the AKSA is offering much higher resolution than the Carver, and remaining undistorted at a much higher output level.
Now to the specifics:
First, a minor hitch. I wanted to see how much feedback occurred via mechanical manipulation of the Gallos’ voice coils, so I initially configured the Carver to drive the speakers’ bass inputs only, with the full-range inputs disconnected. Sure enough, the bass driver generated current through its idle voice coil, which flowed back through the crossover and audibly into the midrange drivers. I replaced the Carver with the AKSA to note any differences. During a particularly spirited bass guitar solo, the amp appeared to oscillate on the left channel. I quickly brought down the gain and it stopped, and I could not get it to do it again. I am no EE, but at risk of inserting ubiquitous quotations around the word oscillate, that was my impression. The sound was not musical, and was a much higher frequency than the source material. Hugh, if it is helpful, the amp was receiving the low-pass signal crossed over at 70Hz with a steep fourth-order slope, the speaker impedance was probably dipping well below 4 ohms, and the amp was subjectively at about 75% power output, based on later preamp settings where it clipped.
Onward to better things. I switched the AKSA to the Gallos’ full-range inputs. The 100 wpc AKSA’s power/gain ratio was slightly greater than the 175 watt Carver. Others have commented that the tour AKSA’s system interaction is similar to an amp with about twice the RMS power, and I concur. Connected to the strong A3cr preamp, the AKSA typically pushed the 88dB Gallos to a spirited volume level at about 5.5/10. A few CDs with very dynamic amplitude required an 8/10 volume. Recordings saturating the audio spectrum caused the AKSA to clip at that level.
The first album I listened to was Scheherazade / Chicago Symphony Orchestra, conducted by Fritz Reiner. It is remarkably mastered, recorded in the excellent (and very large) Chicago Orchestra Hall, and in my opinion, is a reference recording for full-range speakers. The Gallo bass was adequate (unbiamped), but tight. Strings were rendered sweetly and brass was clean and pure, and I could hear their piercing echoes fading into the auditorium. Cymbals were full and clear, with excellent sustain. I know this recording well, and I heard harpstrings, soft percussion and triangle hits during full orchestral passages that had never been there before. When listening to classical, I often move into the nearfield, and the AKSA’s detail just made this a pleasure. Overall my impression was, “Wow, this is up a notch across the board.”
Then I pulled out Dave Grusin’s GRP All-Star Big Band LIVE! to play a rendition of “Sing, Sing, Sing.” While the stereo mix of the percussion is a bit aggressive, this track was the first one to bowl me over. The vibraphone and clarinet were just spectacular. Each strike of the vibraphone hung in the middle of the soundstage and echoed in my head. This track really featured the AKSA’s soundstage depth, and I repeated it several times to solidify my impressions.
I put on Trilok Gurtu / The Glimpse. This is might be described as “International Jazz,” and is one of my favorite albums for demoing my system, as it never fails to astonish people with a never-ending stream of interesting and complex sound. But it was my turn to be floored, because I realized I had never really heard it before. I don’t even know where to start – timbres of woodblocks, musically rushing air, Trilok’s signature rapid-fire percussion, weird phase-shifting guitar play, sparkling-clear bells, aggressive bass licks, the unusual Indian vocals – each moment revealed sounds with subtlety, intricacy and clarity, lovely clarity. During this play, the CD was elevated from demo to critical reference recording.
On to Diana Krall / Stepping Out. True or not, my mind’s eye sees that “Body and Soul” was recorded in a small auditorium with no acoustic treatments, and a hard floor. The reverb of the piano and vocals combine to create this ambiance. The AKSA’s spatial interpretation was convincing, Diana’s vocal was lush and full (well, it always is), and imaging was excellent. I was surprised by a squeaking sound that occurred at various points in the song. At this point, I think it is the piano pedal. The AKSA clearly revealed moments when the mixing engineer cut the vocal mike, consequently the piano’s crosstalk into it, and destroyed that sense of ambiance.
Fleetwood Mac / Rumours (on DVD-A). Overall, this disc was excellent. The band’s syncopated, shuffling rhythms, and leading snare/bass combos were a great match for the AKSA’s speed. “Never Going Back Again,” is really a front for a twin acoustic guitar performance, with the artists placed at extreme left and right of the soundstage. The performances are with picks, and the AKSA’s detail and transient ability really were obvious here. I should point out that the DVD-A mix of this song is quite different than the CD release. I have yet to listen to it with any solid-state amplifier where the guitars did not sound etched, and the AKSA was no exception. I have heard it on a McIntosh tube amp, and they were absolutely lifelike, but the vocal was very muted and diffused.
Enya / Shepherd Moons. This disc really complements the AKSA character. On the title track, the melody line is doubled by guitar and synthesizer. With many sound systems, the attack and timbre of the guitar plucks are lost into the synth and ambient harmonies. The AKSA/Gallo combo really pulled the two sounds apart and created depth in the performance. With this track, it was very easy to explain and demonstrate the concepts of layering and soundstage depth to a friend who had never critically listened to audio before.
Tori Amos / Little Earthquakes. I played the title track on a whim, and discovered something startling. On the lead-in to the chorus, Tori’s center stage vocal is suddenly split into two separately recorded vocals, presented at either side of the soundstage. I had formerly thought that this was just a studio effect diffusing her voice across the soundstage, but with the AKSA I was able to easily discern when the shift occurred, and that it was two individual vocal recordings. Neat!
James Taylor / Greatest Hits. I have never been a James Taylor fan, and bought his greatest hits album just to round out my musical collection. But the AKSA brought out a palpability of the artist’s voice that was just truly pleasurable to listen to. On “How Sweet It Is,” the wood blocks easily extended the soundstage several feet past the edges of the speakers. I was very surprised by “Shower the People.” This song’s signature sound is the xylophone, and apparently I never knew it. The AKSA connected me to the performance in a new way, despite having heard it so many times through the years.
B.B. King & Eric Clapton / Riding With the King. If you don’t have this CD, buy it. My favorite track is the last, “Come Rain, or Come Shine.” Eric sits at the extreme left of the stage, and B.B. is on the right. The whole song, recorded live, puts the two golden voices and their signature guitars (Gibson Lucille vs. Fender Stratocaster) in direct contrast and interplay. Everything is heavily miked. The solos are strong, slow and deliberate, with heavy blooming. Have I built this up enough? Well, the AKSA/Gallo combo sat me down in the first row. I could have reached out and touched the artists, they sounded so close. Another one in the “chills” column.
Next was Dave Brubeck Quartet / Time Out. This timeless album devotes distinct soundstage space to each of the artists, and is a good test of soundstage size, spatial imaging and ambiance. A favorite is “Kathy Waltz,” which opens with piano on the right and snare brushes on the left, and a loping bass in the center. Later the sax drops in between the drums and the bass. The AKSA pinpointed these perfectly, and I was even able to determine which way the piano was facing! The reproduction of the brushes was utterly convincing. In the last few measures, the brush mike is cut and the performance finishes with the piano. Again, the spatial picture collapsed as the AKSA exposed this mixing flaw. A colleague who was visiting at the time thought that the channel had failed. Good with the bad, I guess!
Finally, I listened to a number of rock selections, and while it was more difficult to pull out vignettes of sonic excellence from this genre, the notables that kept leaping off the CDs were incredibly complex renderings of guitar feedback. The AKSA’s ability to sustain those subtle (tube!) harmonics, in the middle of a saturated audio spectrum, was very reminiscent of its performances with cymbals, triangles and xylophones. So much of the rock genre is mastered so badly, and the AKSA is so revealing, that much of my catalog was frustrating to listen to. But it was also thrilling to hear CD’s owned for 20 years as I never had before. Standouts included Pink Floyd / The Wall, Steely Dan / Aja, The Police / Ghost in the Machine, and Eric Johnson / Ah Via Musicom.
To summarize the suitability of the AKSA/Carver combo for the Gallo application: The AKSA performed beautifully as a full-range amplifier with the 88dB Gallos. It did clip at higher than comfortable volume levels. I do wonder exactly how much headroom, with very dynamic recordings, is left in this particular system. Hugh, count me in on the list of folks eagerly awaiting development of the AKSA 200 Nirvana Plus!
Lest you get the wrong impression about the Carver, it was totally unacceptable for the supplemental bass application, both in terms of power available and impedance compatibility with the 4 ohm voice coil. I had to use the crossover’s input gain and low output gain in order to get the Carver anywhere near balanced with the AKSA’s full range output. Needless to say, it clipped early and often set up that way. After about 15 minutes of critical listening, I resolved to look for an inexpensive high-powered amplifier for bass-duty (the Gallo SA amp is looking better all the time!) Any idea of synergy or matching between Carver and AKSA for that application was right out. While I didn’t try it outside of that first feedback test, I doubt that the AKSA would do any better. It’d be a waste of high fidelity anyway!
In deference to the “explore all possible connection permutations” audio rule (a.k.a plug everything into everything), I wired up the AKSA and the DCM Timeframe 400s. These are 2.5-way designs, with a pair of 6.5” drivers and a tweeter mounted coaxially with one of the drivers. Bass is handled via transmission line cabinet and a rear port. Their strengths are imaging, clean midrange and efficiency. The AKSA’s imaging performance with these speakers was absolutely spectacular, at least as good as the AKSA/Gallo combination. But the 100’s power easily overwhelmed the 92dB DCM’s – as the website states, the 55 would have been a better fit. If one was just starting out, buying a pair of TF400’s for $175 and building an AKSA 55 would be an attractive price/performance option.
A note on speaker cables: I tend to build my own out of high-quality wire and connectors. As requested, I dutifully auditioned the AKSA using the supplied Tara Labs Phase Return cables, but later switched in DIY Cat 5 braided, stranded zip cord, and DIY Jon Risch cross-connected 89259s. I fully expected the CC89259 to outperform all others, but my order of preference was:
Tara Labs (hands down the best – not a nuanced, subjectively tiny bit best)
CC89259 (sounded warm and soft after the Taras)
16AWG stranded zip cord (my reference cable)
Cat 5 (yuk. as advertised, high capacitance cables do not make AKSA happy)
I have always felt that the CC89259 and zip cord were roughly comparable in sound, so I built and used the CC89259 for its noise-rejection features. I never had the impression that they were coloring the sound, but the Tara Labs / AKSA combo demonstrated otherwise. At a price hardly more than good quality wire/terminating hardware and labor, the Taras are hardly a difficult decision.
I found it interesting that while double checking facts, I realized that Hugh’s (and others’) various assertions of the AKSA mirror most of the impressions I had already scribbled down for posterity. He’s on the level, folks, and I would guess he pretty much has to be with the open nature of the AKSA community…
For me, the AKSA’s central listening themes included a strong appreciation for the reproduction of the music, open presentation, clarity and detail in spades, and often a totally unexpected surprise worth writing down. The AKSA has its own sound, neither tube-ey nor solid-state-ey. As stated before, brushes, cymbals, bells, triangles and vibes were reproduced as I have never heard before. It was clear that there was some of that elusive audio synergy happening among the AKSA, Gallos and the source components. My personal audiophile benchmarks (a.k.a. Gear In House) are officially elevated. Thanks, Hugh.
For me, the products that might compete with the AKSA 100N+ in price/performance are the McCormack DNA-225, DNA-125 Platinum, and the Odyssey Khartago monos. I’ve heard each of these amps, which also attempt to avoid “solid-state sound”, but I haven’t tried them with the Gallos. I will admit that the draw toward these amps is the desire for just a bit more power, and were I to go that route, am worried about being satisfied after having witnessed the sonic performance of the AKSA.
Hugh and Paul, thank you very much for the audition opportunity. I very much enjoyed the AKSA 100N+ amplifier, and like U4EA, hate to send it on.
Tim
