We celebrate a new feature, which will be appearing in virtually all our future reviews here at Enjoy the Music.com. Click on any image with a red dot/crosshairs to see a much larger, hi-res version!
I have to hand it to LKV
Research's owner and chief designer Bill Hutchins. Although he is certainly not
the first and will certainly not the last audiophile to start a company to
design, build and sell high-end audio equipment out of his home, what surprises
me is that he has chosen to design his components using solid-state circuits
rather than vacuum tubes. Vacuum tube circuits are usually simpler than their
solid-state counterparts, not to mention that solid-state components are usually
not as forgiving when one makes even a simple design mistake. During operation,
when there is a problem with a tube component it is usually because of a tube
malfunction rather than a faulty circuit design. Often, when a vacuum tube
circuit is faulty it will simply not function, often when a solid-state circuit
is fault it will self-destruct, and often destroy the equipment that is
connected to it. Not only that, but solid-state components are a bit trickier to
diagnose. This is why when one decides to tackle their first DIY project it is
usually a simple tube amp. But one must keep in mind that Bill Hutchins is
hardly a novice designer.
Within my review of the LKV Research Phono 2-SB phonostage I disclosed that he had retired as an attorney, but during those years that he was practicing law he was also studying electronics, and he designed, built, listened, tested, modified, and troubleshot amps, preamps and speakers. For his efforts he was able to design, build and market the solid-state Phono 2-SB, which is as good as any phono stage not only within its price class, but beyond. After I reviewed it in the August 2013 issue, I nominated it for an Enjoy The Music.com Best Of 2013 Blue Note Equipment Award in the preamplification/amplification category. In its summary I said that "I found the 2-SB to be one of the most honest sounding and transparent phono preamps I've ever had the pleasure of using in my system." While I was working on my review of the Phono 2-SB Mr. Hutchins revealed to me that he was working on a linestage. I asked him for a review sample while it was still in its design stages.
The LKV Research Line One preamplifier and the Phono 2-SB have at least one thing in common: their rather large "overbuilt" outboard power supply. The Line One's power supply has seven stages of regulation and filtering, which "assures clean DC power for the amplifier 'gain blocks'". These hand-matched Class A JFET zero feedback blocks are designed to amplify low level signals with "vanishingly low noise and distortion". The dual mono design of the Line One splits the right and left circuit boards, which as a rule guarantees excellent channel separation. Also similar to the Phono 2-SB are the use of premium parts to "assure purity of the musical signal". The Line One also has a four-gang stepped attenuator, and controls the volume using discrete 0.1% tolerance resistors. A large majority of the Line One's internal parts are made by trusted parts manufacturers that are often used in audio equipment that usually costs much more than the LKV Research Line One: for input selection ELMA switches are employed, and of course their contacts are gold-plated, and one can also find within the Line One Vishay/Dale metal film resistors that measure within 1% tolerance. Signal path capacitors are WIMA polypropylene, and the internal solid-core wiring is all Teflon insulated, All paths of this internal wiring are made as short as possible, and noise is also kept to a minimum by using four-layered circuit boards. It is not difficult to imagine that when designing the Line One Bill Hutchins didn't just pick these internal components off the shelf because of name recognition he most likely spent hours upon hours using trial and error, and of course listening tests, in order to arrive at what would become the Line One.
Most importantly, though, a system such as mine,
and I've heard this happen in many systems that are not my own, sonically suffer
if a linestage is not used. There have been times when my system was all-digital
(although only for a short time) and the system still sounded better with a
preamplifier. Even the simpler second system located on a lower floor in my home
has benefited from a dedicated linestage in the chain. There are many reasons
why a separate linestage or preamplifier will sound better than simply using the
volume control of a DAC besides that with the DAC it is in the same cabinet
using the same power supply. I'm sure the separate power supply has a lot to do
with it, because of gain demands (the usual culprit), or some other unknown
reasons, in both of my systems they always sound better when using a dedicated
linestage. I'd bet that there are massive DACs with a high quality volume
control with their correspondingly massive power supplies being made and sold
somewhere that could trounce my separate linestage approach, but I have not yet
heard one, and I'm not sure if I ever will.
The PS box attaches to the main unit by a grey umbilical that attaches itself to a connector smack dab in the center of the main box's rear panel. Also on its rear panel are a healthy amount of inputs, two balanced XLR inputs and four unbalanced RCAs. This is where the back panel layout becomes a reflection of the unique dual-mono construction of the Line One. Each input takes the shortest path possible to the differential gain blocks, where all amplification of the signal occurs. So, the two channels of the stereo preamp are at either end of the panel, for example, balanced input 1 has its left input on the right side of the rear panel, its right input on the left side of the rear panel. And so it goes for the remaining inputs. The outputs for each channel are at the far ends of the rear panel, the left outputs on the far right, and the right on the far left. This wasn't inconvenient. It just deviates from what I am accustomed to. The outputs of the Line One are many, two single-ended and two-balanced output jacks per channel. The two types of outputs are fed by separate output current amplifiers, in other words, the two XLR balanced output jacks are wired in parallel for the same JFET unity gain current amplifier. Because of the robust construction of the Line One it is comfortable with low impedances so it can drive as many as four power amplifiers simultaneously.
the dual-mono construction is also reflected on the Line One's front panel, as
two controls are necessary to select the source input. This is in stark contrast
to the Audible Illusions preamplifier that I owned in the 1990s, which boasted
two volume controls, one for each channel. I must admit it was a lot easier, not
to mention more convenient to have to get used to two source selectors than two
volume controls. On the front panel are also two mute/play toggles, one for each
channel. That's it for the front panel other than the LKV Research logo and a
blue power indicator. The Line One has no balance control, no phase selector,
and no tape output. And no remote. I might be one of only a few audiophiles, at
least I'm the only one I know, who is not
bothered by not having a remote control, but actually prefers it that
way. I'm also one of the only audiophiles I know that still plays 45 rpm 7"
records, so I won't take offense if you think I'm "unique". I assume the reason
for the Line One not having a remote is at least partially due to sound quality.
Since you are reading this magazine, I will assume you would also choose sound quality over a remote. In an interview, LKV Research's designer and owner Bill Hutchins said "Everything we've done here is about the sound. Our goal is to give listeners the experience of having nothing between themselves and the music... Listening to music played though this preamp and its teammate, the Phono 2-SB, I find that yet another layer of separation between me and the music is gone. It's a layer most listeners don't know is there, until they hear music without it." Accordingly, it's no surprise that the Line One has a uniquely arranged rear panel and a spare front panel that does away with some of the intangibles that are included in some other brands of linestages. If sound quality is your most important goal, this makes perfect sense.
The LKV Research Line One does add one luxury to its circuit design, the ability to change the amount of gain it provides through its outputs. In regards to preamplifier gain, as Bill Hutchins so eloquently puts it, is that they "make much more gain than is needed". An unavoidable consequence of providing more gain is that noise comes with this gain. In the real world this is unavoidable. It is helpful to note that in regards to a preamplifier's gain, we're not talking about the volume control the volume control does not alter the preamp's gain it is actually an attenuator. Gain and volume control are different. Some amplifiers that are connected to a set of speakers do not need the amount of gain (and certainly not the accompanying noise) that is provided from the preamplifier, so LKV Research has designed the Line One with adjustable gain via internal toggle switches. There are four switches, two for the unbalanced and two for the balanced outputs, which enable the user to choose between a gain level of 4dB, 10dB and 16 dB. The unit is shipped with the default of 4dB, which is fine for most users, including me I left the gain at this setting for the entire audition period, which allowed me to set the volume control at about the 2-o'clock position. Of course, your system might be different. The Line One can accommodate this difference.
In my main system, and where the Line One spent
the majority of its time, I located it on the second shelf of an Arcici Suspense
equipment rack. It fed one of two amplifier systems, either a 350-Watt per
channel Pass Laboratories X350.5 solid-state amp, or a pair of 70 Wpc PrimaLuna
DiaLogue Six vacuum tube monoblocks. When the Pass Labs amp was in the system I
usually used a pair of Sound Lab DynaStat hybrid-electrostatic speakers. The
PrimaLunas were used when the Venture Audio Encore floor-standing speakers were
being used in the system during the first half of the review period. Both
speakers systems were usually augmented by a Velodyne HGS-15b subwoofer. The
digital front end that fed into the Line One was based around a music server
which resided within a 3.20 GHz Dell Studio XPS PC with and 8 Gig of RAM. FLAC
files that filled a few 2 and 3T hard-drives were hard-wired to the computer.
The FLAC files were read on the open-source FOOBAR 2000 supported by Windows 7.
A Furutech GT-2 USB cable was used to connect the server to the DAC, usually
using an AURALiC VEGA (which
I reviewed in the July 2014 issue of Enjoy The Music.com), but
sometimes a Benchmark DAC1USB. Both of these DACs have balanced XLR outputs that
I connected to the Line One.
Late into the review I used the Chord Hugo headphone amp (review forthcoming), which sports an awesome internal DAC that has unbalanced RCA fixed outputs. The occasional SACD and even less occasional DVD-A was spun on an Oppo BDP-83 Special Edition with its unbalanced analog outputs connected to the Line One. I used two turntable systems for the analog front-end during the Line One's stay an Oracle Delphi MK VI (reviewed in the April 2014 issue) and a Basis Debut V. On the Oracle I used an SME V tonearm, on which was mounted either a Lyra Kleos phono cartridge, or a Kiseki Blue NS which is on loan for review. The Basis usually used the Lyra cartridge; it was mounted on a Tri-Planar 6 tonearm. The turntables took turns resting upon the top shelf of the Arcici rack, which has a 70-pound plate of steel under the rack's top acrylic shelf, which in turn sits on three air-filled bladders. As far as cabling was concerned, I violated the one system/one brand rule by using the brand and model of cables that not only sounded the best for that particular component, but length also suited my needs. These interconnect and power cables included those made by MIT, Virtual Dynamics, DH Labs, and Audio Art. All the front end components were connected to PS Audios Power Plant AC Regenerators. The Oracle MK VI used its own Turbo II power supply, but the Basis was connected to its own PS Audio P300 AC Regenerator, which not only provided a pure sine wave of AC, but its frequency could be switched between 60Hz to provide the correct speed for 33.3 rpm records, and 81Hz for 45 rpm records. The power amps connected directly to one of two dedicated AC lines that powered the listening room fitted with Virtual Dynamics wall receptacles. The room is treated with Echobuster Acoustic Treatment panels, LPs shelves on three of the room boundaries, and in some areas detritus from many a late night listening session randomly arranged upon the listening room's industrial carpeting.
I also used the Line One in my second system, the one I spoke of that didn't always use a linestage. This system was sometimes powered by the same PrimaLuna tube monoblocks as the main system, but also often was powered by a pair of solid-state AURALiC MERAK monoblocks (reviewed in the July 2014 issue). The power cords of all the gear was connected to a Chang Lightspeed power conditioner. I used Cardas interconnect and speaker cable, but the power cables were the Audio Art Statement II. Both amps had no problem driving the pair of two-way floor-standing EgglestonWorks Isabel speakers. As good as this system is (and it is good) it is less revealing than my main system. This might be due to its lack of front-end refinement, or perhaps the rather live untreated room. Again, I'm being over-critical. This is a fine system that most many would envy, and was a fine evaluation tool to test the LKV Research Line One. Although the main system was better, so that's where it spent most of its time.
In the main system I arranged the Line One's power supply box so it was able to sit on the floor next to the equipment rack, with its umbilical still having enough slack to easily reach the main box on the second shelf of the rack, which was about two and a half feet off the ground. I was told by LKV Research proprietor Bill Hutchins that all the LKV products are run in a bit before they are shipped, but the Line One would still need to break-in for a while. I wasn't able to listen off-axis for too long, though, as the sound drew me away from working on my computer to sit in the sweet spot quite a few times before the Line One was fully broken-in. I suspect the amp was fully broken-in when I started my "serious" listening sessions, but to be honest, although I did hear a bit of difference after a while, this difference wasn't huge. In the Line One's manual it states that the component sounds better after about an hour of use, to make things easier on myself I powered the unit either at the start of the day, or when my listening session started, whatever came first -- and then left the Line One powered until I was ready to turn off all the lights in the house at the end of the day, or the end of my listening sessions, whatever happened last. How much power the unit draws isn't specified, although I figure it is only a few watts when no signal is passing through its circuit so there was little harm in powering the unit when it was idle. The cabinet of the Line One's main box and its power supply didn't get warm during operation. In fact, even after some very long listening sessions the both of the cabinets' temperatures remained cold to the touch. The manual states that the main component doesn't need much room around it when choosing a space to set it up and I believe them. If it weren't for the risk of having some stray signal enter the cabinet and the risk of it causing noise, I wouldn't hesitate stacking other components on top of the Line One.
In regards to the LKV Research Line One's sound quality, the Line One does not pretend to be anything that it is not, as it wears its solid-state badge proudly although it's transparency to the source is a trait one is most likely to notice, its super-clean sound will not fool anyone into thinking that its circuits are powered by tubes. In most respects, I mean this as a good thing. There were times, especially when I wasn't listening too loudly that it seemed as if the Line One wasn't even part of the signal chain. I could listen to my favorite LPs or digital files unencumbered by thoughts as whether or not the linestage was contributing or not contributing anything to the sound of my system. If I cranked the volume up a bit more the Line One's presence was made more obvious by injecting a bit of what solid-state is good at deep, thunderous, and tight bass, a clear, transparent midrange, and high frequencies that seemed to reach to into the stratosphere. The Line One's soundstage might not be the most spacious I've ever heard, but the images within its soundstage sounded as if sculpted by a skilled surgeon's scalpel, each image in a sharply defined area and placed appropriately. This last characteristic might not sound so great, especially for tube loving audiophiles who are accustomed to having a certain amount of sweetness in the treble. But when listening this characteristic struck me as one that seemed reminiscent of a linestage where if its raison d'etre is to be transparent to the source while providing the necessary gain to send along the signal to the power amp.
I feel as if my writing is a bit forced here, that breaking down the Line One's sound into aural compartments is not how things work in real life. When playing an album through the Line One, especially if it is good music I'm listening to, it isn't as if I can patently hear each of its characteristics broken into slices of audiophile terminology. Yes, if one concentrates on the sound of a particular instrument there is no question that one can hear that its outline is sharply drawn in space, but that's not how one listens to music, is it? I've said this at least once before, but it isn't as if one goes to hear an ensemble in concert and utters, "Wow, listen to how sharply the images of that instrument are drawn in space!" But the way in which the Line One is able to render images in its soundfield is representative of its overall sound, which is not only transparent, but precise in the way in which it is able transfer the signal to one's amplifier, and if one's amp or amps are up to it, to one's speakers. So, if the images on a recording are sharply drawn, the Line One will transfer this trait. If they are not, it will not.
When I spun my copy of the latest vinyl re-issue of Pink Floyd's Wish You Were Here pressed at Quality Records and issued by Acoustic Sounds, it was made clear that it is not only the best pressing I've ever heard of this LP, but also the best I've ever heard it sound in my system. After all these years of playing this record it is such a joy to hear new things in these grooves. But to be honest, the first thing I noticed was the bass, which was, in a word, astonishing. Not only did it rival the SACD version of the album, but in many ways it was better. It reached as low as my system would allow, had the power to shake the window frames in the room, but also had a transient response that let me follow each line regardless of what was happening above these frequencies, even though the bass on this album isn't the most uncolored, crisply recorded bass that was ever recorded. The Line One was also very musical and very revealing -- and I never realized how much counterpoint was composed on each of the songs, especially the main "Shine On... " theme, where the interplay of David Gilmour's overdubbed guitars and Rick Wright's keyboards shape the sound and keep the listener engaged throughout the album's long first and last sections.
Despite the minor idiosyncrasies of the recording, throughout it all Nick Mason's extremely solid sounding kick drum along with his often improvised sounding tom-tom interjections, combined with Roger Water's mercurial bass are evidence of the Line One's taut low-frequency response. Yet the midrange is the star of the show. During "Wish You Were Here" I could hear the overdubbed acoustic guitars as if viewed through a transparent sonic window into the studio. The acoustic guitars and vocals are obviously where the Line One's ultra-transparent midrange shines, as the Line One demonstrates that it can be both invisible and conspicuous invisible because its seems as if I was hearing straight through to my Pass Labs phono preamplifier, and conspicuous because I've never heard such deep low end, such a transparent midrange, and a far-reaching treble when playing this record. The old audiophile adage of "the equipment got out of the way and let the music through" is certainly applicable here, but it is also tough not to notice the Line One because of such a fine job it does making this album "new" again. Not an easy task for a record I probably heard a thousand times.
Long time readers are well aware that I listen to lots of Gustav Mahler's symphonies. And why not? Mahler has a great bio, and the events in his life are constantly being interpreted and reinterpreted by those who enjoy imagining these events as interwoven into the picturesque themes within his works. Even more impressive is the way he intertwines layer upon layers of relatively complex counterpoint and orchestration, not to mention the forces that Mahler employs that make for some great audiophile listening experiences. The different interpretations that I've collected of orchestras and conductors throughout the years provide plenty of food for thought, although these days most versions sound more alike than dissimilar due to many reasons that are obvious to those who follow this sort of thing, but I don't have the space to go into detail here. Still, the skills of the orchestra, the conductor, and the recording engineers and producers are certainly put to the test with a Mahler symphony. It is understandable that not all share my fondness for this composer, some find his works just too convoluted, but my love for Mahler's symphonies and my familiarity with these works and many of the recordings have made me quite opinionated on the subject! Mahler's Third Symphony is perhaps one of his most "difficult" works, both for the listener and those responsible for playing it, not to mention recording it it's first movement is over 30 minutes long, and the entire symphony clocks in at over 90 minutes or more. It requires not only a huge orchestra but also instruments located off-stage, a chorus, boys' choir, and a vocal soloist.
Sometimes I'm presented with an interpretation of Mahler's Third Symphony which I do not terribly care for, but the recording quality is so good I can overlook the fact that it is not the best in the large catalog of offerings. This is the case when considering Riccardo Chailly's version with his Concertgebouw Orchestra on Decca released in 2004. The first movement is taken at a pace that I initially thought drearily slow. Although this version is only a couple of minutes longer than what others take to wind their way through it, I always felt that it drags, especially at its onset. There is no denying, though, that the recording is one of the best. There are even many characteristics of this recording that place it among one of the best orchestral recordings in my collection, but the character of the recording itself, combining both the strong leadership of Maestro Chailly and the way in which they perform Mahler. The Concertgebouw's history with Mahler is well known, with the composer conducting many of his symphonies with the orchestra.
Played through with the LKV Research Line one in the system, the recording of the concert bass drum in the introduction nearly made me jump out of my listening seat, as its resonance rattled anything not securely fastened in my listening room. But it wasn't just its volume and depth that made this drum's sound so startling its sound could be heard resounding throughout the recording venue. It was as if I could "see" the air pressurize within the first hundred yards of the theater's proscenium. OK, this is the type of "sonic spectacular" that impresses the layperson as well as the audiophile, but it was the less ostentatious traits of the Line One that one will be aware of if selected to be part of one's system throughout its lifespan. And so, thankfully the Line One's transparent midrange will be more noticeable in the long run. Some might interpret this midrange as being a bit forward, as it brought these frequencies more than a bit out in front of the plain of the speakers, a row D rather than row H perspective. Many would expect this trait to be detrimental, but in many ways it wasn't, as it was in keeping with the Line One's ability to let me hear many details in the recording I haven't noticed before. This was of course true in non-orchestral recordings, where the inner-details of just about every instrument that has a good amount of mid-range energy (in other words, just about all of them) were revealed. Hearing the Concertgebouw's string section play as one mind is patently evident on this double disc set, making it quite that their reputation is well deserved, at least when it comes to reading, performing, and recording a Mahler score.
It helps that this Decca recording made in 2003 is very, very good, and is one of the discs I turn to when I want to demonstrate how an SACD's treble makes mincemeat out of the treble on an "ordinary" CD. And here it is for all its glory on this SACD and with this score a perfect vehicle for demonstrating this quality. During the first movement we hear snare drum, cymbals, tambourine, tam-tam, triangle, glockenspiel, and perhaps some more percussion instruments that I've not been made aware of, not to mention the woodwinds that reach into the upper registers that wouldn't sound nearly as good if the Line One's treble response wasn't up to the task. The Line One's treble is, like I said, decidedly solid-state, so it is missing that warmth that make tubes so inviting to so many, but still, the Line One's treble manages to reach these upper-registers without committing any sins that would annoy those with sensitive ears so it was just as important which traits the treble did possess as which traits it didn't possess. There was no discernable grit, grain, or untoward sibilance in even the highest reaches of these frequencies. What remained was one of the most natural sounding high-frequencies I've heard from a solid-state preamplifier, so as a result the preamplifier's treble didn't call attention to itself and sounded as if for the most part it was simply passing on what the source component was feeding it and then passing this signal to the power amplifier.
It also helps that the background of the Line One is a completely silent one. Whether this silence is due to the physical distance created by having the main unit and its power supply in separate cabinets, good engineering principles, or a combination of both, having music arise from the black background added to the perceived dynamism of the music. Depending on the quality of the source material added to the illusion that I was listening to a copy of the master tape rather than the music passing through the high-quality circuitry of a high-quality linestage.
A Good Fit
I could continue, and discuss what I've heard
with more records and digital files to bear witness to the LKV Research Line One's
midrange transparency prowess, its very deep and tight bass, extended and
sparkling treble, transient speed, its adeptness at creating pin-point images,
and crystalline clarity. But I'd just be repeating myself. One may have noticed
that when using musical examples to illustrate the characteristics of the Line
One I discuss the particular music selection almost as much as the traits of the
component. This is because when listening to the Line One the music is what is
being featured, not the equipment. This is because the Line One sounds more like
music than a piece of audio equipment. There is no higher praise. The Line One
might not have many extra features, so it might not be perfect for every system
(show me a component that is!) but this linestage is certainly worth its asking
price, and its fine performance throughout the audition period has proven to me
at least, that I can recommend it to anyone who is searching for a linestage at
or anywhere near its price.
Single ended output with volume control at maximum:
Fuse: 1.5 Amp, fast acting