The power supply is substantial, heavily regulated and using a 35-watt transformer that’s a lot bigger than it has to be. Avid is obviously a fan of oversized power supplies; their much more costly Pulsar has a power supply that’s almost ten times larger than that of the Pulsus. I’m a big fan of large power supplies too. They ensure that a device maintains performance and specs even when under extreme stress. It’s not hard to achieve good specs under low stress, but there are cases where a musical peak can be a very short burst of 30, 40 or even 50dB above the average listening level. A unit needs to be able to meet those demands -- and recover afterwards, even from a very short overload. This is where a good power supply proves its worth.

I connected my VPI HW-19 turntable, still carrying the Shure V15 V MR cartridge (not the later XMR) with Jico stylus, to the Pulsus. I always use the Shure with the damper brush down because I like the effect of damping on signal decay. It’s also essential to use the damper with my Fidelity Research FR64fx tonearm, which has higher effective mass than is ideal for the Shure, and the damping mitigates the associated problems. I checked the overhang and set the tonearm level with the platter as a starting point for VTA, but 'arm height needed to be set precisely and you don’t often get that lucky. Initial listening was very nice, but not something for which I would trade my CD player.

Setting VTA on a tonearm that has just a sliding pillar, as mine does (and most 'arms without a micro-adjustment facility), can be a pain. I improved the performance on my first try, but I knew it could be better. I could kick myself for being cheap when I purchased the FR64fx. I should have bought the stabilizer base with the fine VTA adjustment. Hindsight is always perfect. But then I recalled a trick taught to me about 30 years ago by George Bischoff (of Melos, Pipedreams, Scaena and GeorgeMark Audio). I don’t know where George learned it, but since I had never come across it before, I call it the Bischoff Method.

First, set the tracking force of your pickup in the middle of the recommended range. Then roughly set the VTA as well as possible, varying the pillar height to give as focused a sound as you can in a few minutes of quick adjustments. Alternatively set your 'arm parallel to the platter. Tighten the 'arm height screw. Then take advantage of the vertical tracking force (VTF) adjustment on the 'arm. This can normally be precisely adjusted without too much trouble (although some unipivots that combine VTF and azimuth on an uncalibrated counterweight are not so simple). Dynamically balanced 'arms like the Fidelity Research (as well as the SME 5 and Linn Ittok and Ekos) make it especially simple. Make very small changes back and forth, beginning with just a couple of hundredths of a gram. Increasing the VTF lowers the angle the cantilever makes with the record surface and vice versa. If your initial VTA setting was close, then the sound should lock into precise focus, indicating you’ve hit the correct VTA, while even a tenth of a gram change in VTF should have no effect on tracking performance if you started from the middle of the recommended VTF range. This method is not perfect, but given that it’s a one-time setting on an 'arm like this, it delivers way better performance much more easily than trying to adjust the 'arm height in ever-smaller steps.

While most of my listening was with the Shure V15 V MR, I also used two other pickups in order to ensure that results were consistent with other cartridges. One was a Technics EPC-205C Mk 2, also with a Jico stylus, another excellent moving-magnet cartridge. I also used a Goldbug Clement II, a lower-output moving-coil cartridge, to check the performance of the Avid Pulsus on its higher gain settings. In both cases, the results were essentially similar to those with the Shure, save for the expected differences in the three cartridges. The alternative pickups were slightly softer and airier in the upper octaves. The Shure was crisper and less subtle there, but more assertive in the lower octaves. The higher gain options resulted in no discernable alteration in musical, dynamic or tonal performance when compared to the moving-magnet setting.

ecause dynamics are of primary importance to me, the first recording I put on to get a sense of a system’s -- or rather a component’s -- dynamic capabilities is usually the Evgeny Kissin CD of Pictures at an Exhibition [RCA 63884-2]. A concert piano is just about the hardest single instrument to reproduce, because it is capable of monster dynamic swings, sometimes lasting for just split seconds and then dying quickly away. It’s a mighty test of both the ability to handle the rapid rise in signal level and also its proper decay. Overshoot or softening on the leading edge are obvious as stridency or a loss of percussive impact, while if the decay lasts too long, it muddles the notes that follow.

I don’t have the Kissin version of Pictures on LP, but one of the joys of searching through old software is discovering forgotten treasures, in this case a recording of the Beethoven Piano Sonata No.23, "Appasionata," by a Japanese performer, Ikuyo Kamiya playing a real battleship, a Bosendorfer Imperial [RCA RDC4]. A direct-to-disc, 45rpm recording, it was exactly what I needed for testing dynamics. Serious low-frequency energy is often compressed on a record because the grooves needed to maintain that kind of musical power are too wide to track properly -- and they take up too much space. Commercially, that’s a loser, and commercial considerations trump fidelity. But this was obviously not a normal commercial recording, and it didn’t disappoint. Energy seemed to just fly off the keys, and lower registers were powerful enough to sound nearly live in level. If you’ve been close to a concert piano you know what I’m talking about. Here’s one place where a CD can ultimately beat an LP. As long as you don’t exceed the mathematics of dynamic range, the CD can be totally accurate. I don’t believe an LP can match the digital disc, at least if it’s recorded at a decent level. But shorn of such practical considerations, the reproduction here was totally rocking, filled with drama, energy and excitement. The Pulsus really felt like it got every last bit of dynamic energy off of the LP, an LP at the limit.

I next put on that audiophile war-horse The Sheffield Track Record [Sheffield Lab 20]. I had forgotten over the years just how dynamic and powerful this LP really is. I cranked it to the sort of levels you shouldn’t maintain for very long, just to see if it would put the Pulsus in any peril. There were no problems. Once again, dynamics soared effortlessly and decay was rapid and clean with no apparent overhang. In addition, this time I got to hear some awesome dynamic interchange between multiple instruments, without any bad interactions or confusion -- another good omen.

I love British folk music, my favorite group being the original Pentangle of the late '60s and early '70s, an all-acoustic ensemble of two guitars, drums, upright bass and a pure-voiced female lead singer. Usually called folk rock, in this one case where folk jazz might be even more accurate (lead singer Jacquie McShee was originally a jazz vocalist). One of the first CDs I always play is The Pentangle [Castle 06076 81120-2]. Unfortunately most of my Pentangle LPs are on the Warner Bros. label. The Pentangle was the first non-classical recording reviewed in Stereophile, and it got a very positive review for both music and recording quality, but J. Gordon Holt received a ton of letters asking what he was listening to -- that the recording was barely okay. It turned out that Gordon had a Transatlantic pressing and most readers had the remastered Warner Bros. LPs, which were two-dimensional, less well defined and less focused than the British pressing.

But once again, luck played a part, and amongst my LPs I uncovered a Linn pressing of the Pentangle album, Basket of Light [Demon Records Trandem 7]. Hopefully this will keep happening, this rediscovering of old gems. It feels like getting great software for free. I still have plenty of my collection to search through.

This recording didn’t disappoint. The transients of the two guitars were clean and fast with no sense of overhang, similar to the sound of the Pentangle CDs I have. Jacquie McShee’s voice had that subtle throatiness I expect from good reproduction. Imaging was very good -- this was the first time I took real note of the system’s imaging with the Pulsus in use. Imaging is important to me but a secondary factor. If it’s there, I love it; if it’s not, I usually don’t miss it. Thinking back to other recordings, I recalled that imaging had varied from okay to very good. That’s a good sign. It means that the imaging was a function of the software, as it should be, being reproduced accurately by the Pulsus rather than added by the replay chain. But when it was good, it was very, very good, with a real sense of space, volume and especially height, creating a three-dimensional view of the music of Basket of Light.

I noted how well the drums were reproduced. The Pulsus allowed me to sense that moment just before the drumhead was hit as well as the decay after the strike, the sign of a very good component. I’ve often heard systems, with software I know, where the drum was very clean, but all I could hear was the drum beat itself. You don’t get the echo-like effect of the decay after the strike. That’s not bad, but it’s not an A+ either, as it was with the Pulsus.

I’m a big fan of Charles Ives' work. On the B side of one of my Ives albums [Deutsche Grammophon 2530 048] I found Carl Ruggles' Suntreader, a very Ivesian piece but with its own personality. The recording by Michael Tilson Thomas and the Boston Symphony again confirmed the dynamic capabilities of the Pulsus. Drums were good enough to make me imagine the real thing and imaging was beautiful, a continuous swathe of sound from right to left, with a sense of space further to the sides and of height above the orchestra. There was also a slight brightness to the strings, not the first time I heard this.

Of all the albums I played, it was these last two that summed up the personality of the Pulsus. All phono stages have a personality. Getting the RIAA curve exactly right demands extreme precision, and I’ve never heard a totally flat response with any LP I’ve listened to. Some very fine sounding phono stages are often quite a bit off, with a hill-and-dale measured response of a dB or so in spots. With the Pulsus, I consistently sensed a tad of brightness -- not much, just the tiniest amount, so one would define it as heightened or illuminated rather than absolutely neutral. It’s just that littlest bit, and it will be important to you if you are very sensitive to it. I’m not referring to the highest octaves here, but to the upper midrange, about where a midrange driver crosses over to a tweeter or slightly above. But then, isn’t that where most brightness usually is? It’s rarely a top-octave problem.

Another characteristic I noted was a sense of weight and palpability in the bass and midbass. This was particularly apparent when playing Suntreader, but it was present with everything I played that ventured that low. It’s not a frequency-response thing. I’ve seen response curves for the Pulsus, and even with the difficulty of getting a flat response with RIAA equalization, it’s dead nuts flat there. It sounds like a little bump, although I don’t believe it is. More than likely it is a result of the dynamic response of the unit. More importantly, the bass was tight and very well damped. If it weren’t, it would be one of those characteristics from my list of factors I’d jump on, one that would disqualify the Pulsus for my own use. I like the effect; it added a sense of liveness and substance to the reproduction.

It was this barely noticeable brightness and innate feeling of power and mass that defined the personality of the Pulsus. It was possibly why I’ve also seen the Avid described as more for pop than classical music. I guess if you think of pop as loud and classical as properly behaved, that makes some kind of sense. But pop music is usually loud though not dynamic. In that sense, it’s often less exciting than classical, where dynamics range all over the scale. I recall many discussions with Gordon Holt in which he deplored audio gear that smoothed out classical sound. He wanted the trumpets to blare and the dynamics to jump. The Avid Pulsus does just that.

That solid bass also meant that you had better make sure that there are no bass problems or low-frequency feedback issues with your system. The Pulsus’s bass response was not rolled off at all. It continued all the way down, well into single digits, so you’ll either need a rumble filter somewhere in the system, or better still some good acoustic isolation for your turntable. Be sure your 'arm/cartridge combination doesn’t resonate too low in frequency or too vigorously. Tonearm damping (or cartridge damping, like the brush on the Shure V15 V MR) can be your pal. Some suspended 'tables handle this on their own. Otherwise a good isolation device below your 'table can help. I have my speakers about 20 feet away from my turntable and in another room, while the turntable is still mounted on a modified Lead Balloon stand with lots of added mass as well as racquet balls for decoupling.

Finally, before getting ready to pen this review, I put on Bonnie Koloc's Close Up [Epic 34184]. Koloc is a fabulous female vocalist, easily in my top five, who made some wonderful recordings in the '70s and '80s, none of which has ever made it to CD. So a phono stage was a true gift, allowing me to listen to all of her albums that I have. On Close Up, the imaging changed again to match the recording. It was almost holographic. There was a super cleanliness to individual instruments and to Koloc’s voice. I heard her vocal soar effortlessly, almost Ella-like in its lack of constraint.  On "Clocks and Spoons," there’s a recording of tap dancing, and the crispness and cleanliness of the individual taps really allowed me to hear just how much information the Pulsus let through -- and just how clearly it defined and arranged that information.

iven everything I've said about the Avid Pulsus, is it too good to be true? That depends on whether its character and capabilities match your demands as precisely as they match my own. In my system, the Pulsus was a perfect fit, and I’ll repeat what I wrote earlier in this review: I bought it, and with each passing day and each record played I enjoy it more and more. I rediscovered old favorites and uncovered hidden gems, a mother lode of musical pleasure from past decades of record collecting. Ask yourself what sort of listener you are, and if you are anything like me, you’ll love what the Avid Pulsus does for your LPs.