Audio Research • LS17 SE Preamplifier

". . .a true great."

by John Crossett | April 23, 2014

t doesn’t seem that long ago -- though it was actually six years -- that I was praising the Audio Research Corporation (ARC) LS17 line-stage preamp with words like ". . .while using the word 'bargain’ to describe a $4000 preamp may be a tad presumptuous, within its price range, the LS17 is exactly that. You’ll find yourself having to pay far more money for less than what the LS17 offers." And I meant every word.

Thus, on finding out that Audio Research had created a Special Edition (SE) version of the LS17, that nugget of news had me champing at the bit to get it in-house for review. After all, the LS17 had been the heart and soul of my system ever since I’d first heard the sweet music it was capable of making. What in the world could ARC have done to improve on what I already considered was the best preamp at its price? I mean, just making a few parts and circuit changes will change the sound only so much, right? Yet I also knew that ARC has a long history of allowing advances made in their top models to trickle down to their lower-priced offerings, and the upgrades they’d made to their Reference 5 SE preamp had earned high praise indeed. I sincerely wanted, I really needed to hear if they could improve upon the LS17. Was this a case of better, or just different, or (whisper it quietly) not actually as good?

The size of the case is unchanged; outwardly, the first thing you’ll notice is that the faceplate is different. Gone are the black plastic buttons and optional black handles -- the Special Edition of the LS17 sports round, metal buttons to switch between power, monitor, processor (i.e., home-theater bypass), and mute. The black inset with its LEDs to indicate the status of power and mute on/off, the source selection, and the volume level are the same as on the LS17. The only other outward difference is that the faceplate now says "LS17 SE." Around back, the new model has exactly the same inputs and outputs as the LS17: two balanced and four single-ended RCA inputs, a tape loop, and one set of unbalanced RCA and two sets of balanced outputs. There is a 15A IEC socket for either the supplied power cord or one of your choosing. The remote control is identical to its predecessor's.

So, what changes has ARC wrought to justify elevating the LS17 to SE status? When in doubt, ask -- which is exactly what I did. Dave Gordon of ARC explained that they’d replaced the LS17’s large coupling capacitors with ones taken from the LS27. Then they added the same Teflon bypass capacitors used in the Reference 5 (the original LS17 had no bypass capacitors), along with "some other nonspecific ‘enhancements.’" Because there were no changes to the circuitry, all of the other changes can be retrofitted to the LS17 should owners want the upgrade.

Could the Special Edition’s relatively small changes in components really improve on the benchmark performance of the LS17? Therein lies the rest of the story.

hen ARC launched the LS17, they called it the "baby Ref," referring, at the time, to the top-of-the-line Reference 3 line-stage preamplifier. In the interim, the Reference 5 was introduced and then relaunched in a Special Edition, and that upgrade having been so well received, it was no surprise that Audio Research would want to give the rest of the line, including the LS17, the SE treatment as well. As noted earlier, given how I felt about the original LS17, if ARC could improve on its sound, then the LS17 SE must be wicked special. I began reaching for the CDs and LPs that I usually use in my reviews to hear what, if any, improvements a new component might make to both the sound of my system and my enjoyment of the music. I call my stereo the Time Machine -- on good days, it can transport me back in time to those moments when some of my favorite music was created. The LS17 has given me many such moments in the years I’ve used it.

Once the LS17 SE had been given a good amount of burn-in time, I began serious listening with a CD that has become one of my staples for both enjoyment and reviewing: Andy McCloud’s Blues for Bighead [Mapleshade CD 07832]. Over the years, I’ve found that this disc gives me an immediate glimpse of any improvement or degradation in my system’s sound. What I heard was more -- more of everything. Like Dr. Frankenstein, the first words out of my mouth were "It’s alive!" The McCloud album was recorded live in the studio, with a very real sense of atmosphere and presence. The CD opens with McCloud at the left rear, calling instructions to the band. Drummer Lewis Nash is at right rear, answering McCloud and tapping his foot on a raised wooden platform. The sound of those foot taps was far more natural, the platform more obviously hollow, the end result far closer to actually being in Mapleshade’s recording studio than I’d ever heard before. McCloud’s bass was not only fuller, deeper, and more wooden-sounding, there was a greater sense of the man himself standing there plucking his instrument. Steve Nelson’s vibes had more shimmer, but also a greater sense of Nelson standing there with his mallets, hitting the various aluminum bars. Yes sir, things had started off very nicely.

Next up was another live-in-the-studio recording, this time on LP: Dave Bailey’s One Foot in the Gutter [Epic/Classic Records BA 17008]. I regularly use this for reviewing because of its precise placement of each musician and the sense of atmosphere captured by the recording engineer. And I truly enjoy the music. With the LS17 SE in the system, the recording studio seemed more real; I felt more involved in the proceedings than ever before. Bailey’s voice, as he announces each tune, sounded much more like the voice of a real person as he sat behind his drum set toward the right rear. Each instrument was that little bit more realistic. I was especially entranced by how easily I could tell when Clark Terry was playing his flugelhorn instead of his trumpet. There was more body and heft to the larger instrument, plus a deeper, richer sound than a trumpet can offer. In either case, there was also a greater sense of Terry blowing through a metal instrument. Peck Morrison’s bass was more pronounced without stepping over the line to overblown. The LS17 SE made a noticeable difference simply by doing everything just that little bit better. It seemed to be a case of stripping away another layer of electronic haze to offer a more open window on the sound.

A great preamp needs to offer more than just precise image placement and razor-sharp imaging, and my first experiences with the LS17 SE were definitely hinting at greatness. As well as the improved separation and positional clarity, there was that extra sense of each instrument’s individual identity and character: the ability to make an acoustic guitar sound like an acoustic guitar. Wanting to investigate further, I reached for my favorite recording of acoustic music, Tiny Island [Opus 3 19824]. Chock full of diverse acoustic instruments, this SACD is also musically satisfying -- if any new component can’t portray each instrument as an individual entity with a distinct sonic signature, it fails in one of its major tasks. The LS17 SE didn’t disappoint -- this definitely wasn’t my old LS17. "Black Sand" captivated me with its musicianship and the sound of each instrument. The opening guitar solo was magical. I could not only feel (and, in my mind’s eye, see) the fingers strumming and picking the strings, but also how each pluck of a string excited the instrument’s wooden body and formed each note. I could close my eyes and feel I was in the presence of the musician. Each note was clearly shaped, from opening transient right through to the final vestiges of decay. Percussion instruments such as marimbas, chimes, and wood blocks each had their own sound and were sharply defined. The tone and timbre of each instrument were fully as real as I’ve ever heard, and way better than my system had reproduced in the past. Finally, a true sense of the room acoustic infused the music, adding to the sense of realness.

The 45rpm vinyl edition of Jackie McLean’s Jackie’s Bag [Blue Note/Analogue Productions ST-84051] really highlighted this aspect of the LS17 SE’s way with tone and timbre. It sorted out and clearly defined the differences between McLean’s alto sax and Tina Brooks’s tenor. I got a real sense of the instruments’ different sizes and how that affected the tone of each. Both were reproduced with a feeling of presence and breathy realness that helped ratchet up the enjoyment factor a notch or three.

Timing and tempo are also crucial factors. A component that drags its feet robs the music of life and energy, while one that speeds things along does just as much damage, making the music seem hurried, congested, and pressured. The LS17 SE seemed able to start and stop on a dime -- giving change as necessary -- while keeping the music flowing, just as the artists intended. From the rock of Supertramp to the jazz musings of Duke Ellington’s big band to the infectious sounds of Mozart, the LS17 SE was up to any challenge I threw at it.

So far, so good -- but for any preamp to make me feel as if I’m in the presence of live musicians, wide dynamic range is a must. The LS17 SE excelled in this regard. I first noticed this when playing "Four Strings," from a 45rpm edition of Paul Chambers Quintet [Blue Note/Music Matters 1564]. Chambers is taking a bass solo, his sound full, deep, and appropriately woody, but a bit lower in volume than the surrounding instruments. Suddenly, trumpeter Donald Byrd pops in, and wow, was there a startling difference in dynamics! Byrd’s trumpet seemed to leap out of my speakers, in contrast to Chambers’ plucked bass -- yet both were reproduced just as I would have heard them had I been in Rudy Van Gelder’s studio, where loud really did mean loud but quiet didn’t mean inaudible. That ability to simultaneously reproduce both ends of the dynamic range is crucial to maintaining clarity with denser recordings, something the LS17 SE made clear as it dug even deeper into a couple of my favorite SACDs: Ben Webster’s My Romance [Top Music SACD8020.2] and Dead Can Dance’s Into the Labyrinth [4AD SAD 2711 CD]. The Webster contains tracks by both a small big band and a quartet, while the Dead Can Dance is a mélange of sounds that create an otherworldly atmosphere. In the Webster, I could easily hear each instrument and how it helped make up the musical whole, while on the Dead Can Dance disc, the LS17 SE sifted through the dense layers of sound, keeping them all distinct while still binding them together to create the dreamscape this group intended us to hear.

I found little, if anything, to quibble about with the LS17 SE. The improvements wrought by the SE upgrade have taken what I considered to be a superb line stage and made it into a true great. My enjoyment factor climbed with each LP or disc I played -- surely the measure of any preamp’s quality. Are there better line stages available? Sure. Audio Research itself makes at least three. But they cost far more, so it’s up to you to decide if the cost/benefit ratio is worth it to you.

hen I reviewed the LS17, I stated that it ". . .was like John Wayne: unflappable, cocksure, authoritative and quietly powerful. There was a tactile realness and a distinct sense of the recording venue, along with deep, tight bass. Its highs seemed to extend into the stratosphere, allowing for great portrayal of space -- which showed ample layering and depth -- together with abundant detail."

Well, with the Special Edition upgrade, the LS17 is still John Wayne, but now in Technicolor. The bass of the SE, while not much deeper, is more detailed and clearly defined. The midrange has even more of that tactile sense of real instruments in real space. The feeling of being in the recording venue has been enhanced far more than I thought possible. The top end, which with the LS17 was already extended as far as I thought it could be, now has further layers of musical definition. Finally, the sense of space between and around the musicians has expanded, reinforcing the feeling of being there. It gave me more of those suspension-of-disbelief moments than I thought possible from such seemingly insignificant changes.

In describing the original LS17, I also noted that "It doesn’t offer the widest or deepest soundstage I’ve heard, nor does it sound as three-dimensional as the best preamps on the market. It lacks the ultimate sparkle and extension on top as well as the fullest authority at the bottom. While it is very quiet, it does not have the purest, blackest, most silent background. Nor does it dredge up every last scrap of detail." Well, the SE still doesn’t offer the widest of soundstages, but in that department it’s a considerable improvement over the LS17. It’s also much closer to highest-priced preamps in its ability to flesh out both instruments and voices. There’s more sparkle, life, and energy in the top end, though the LS17 SE is still not the equal of ARC’s Reference 5 SE -- but then, you’re not paying the Ref. 5 SE’s price, are you? And too, the SE’s background is far darker than the LS17’s, revealing more instrumental detail. So while still not the perfect preamp -- does such an animal exist? -- the LS17 SE offers a distinct improvement in every aspect of musical reproduction over the original LS17. The increments might be small, but the cumulative effect certainly is not.

The old LS17 was a benchmark product in its price range, and I openly wondered how it could be improved. Audio Research has made me eat my words by creating a better LS17. But what makes the LS17 SE most special is that owners of LS17s can get all the same benefits of buying the new SE simply by sending their units back to ARC to be upgraded -- for only $1200, including the new faceplate. In my book, that’s a win/win -- and kudos to ARC for making this possible and not just pushing the new model.

f you’re shopping at the high end of audio, then you’re already aware that the LS17 SE’s price of $5500 is closer to the low end of the price range for a high-quality line stage than the very top, which can run into the tens if not hundreds of thousands of dollars. But by significantly raising the performance bar, the LS17 SE doesn’t just reinforce its benchmark status within its own price range, it becomes the standard against which many more expensive products should also be judged -- it really is that good. If you are in the market for a line-stage preamplifier at anywhere near this price, or you just want to hear what a really great preamp can bring to a system, give the LS17 SE a listen. I bet you’ll have that checkbook or credit card out faster than you can say, "Yes sir, I’ll take it."