Ive always assumed that passive preamps are the hair-shirt audio equivalent of milling your own flour or cutting your own hair. Theyre supposed to be for extremists. After all, if there were anything to this passive business, wed all be using passive preamps, wouldnt we?
So it was with a resigned sigh that I agreed to review the FT Audio LW1 passive preamp, nicknamed Little Wonder by its manufacturer. While this thing might sound OK, I thought, itll probably lack dynamics or bass, or something, and odds are itll only have two inputs and be made from folded tinplate with sharp edges.
Theres nothing like getting kicked in your preconceptions when you least expect it. Imagine my surprise when I opened up the shipping box and pulled out a jewel-like, beautifully constructed unit with five inputs. OK, it looks great, but theres still time for it to sound bad and allow me to continue on with some sense of order in my life.
A sense of wonder
Passive preamps are a startlingly good idea (theyre unpowered units that only attenuate the signal, and as we all know, the less thats in the signal path the better), but theyve never really caught on in a big way. Long, high-capacitance cables, low input sensitivity and input impedance on amplifiers, and low gain and/or low current-drive capability from source components may preclude the use of a passive preamp in some systems. But for those systems where all is right, the simplicity of a passive unit can offer dramatic advantages at significant savings.
FT Audio is a six-year-old company in based in Hong Kong, and Fred Tang, who is chief engineer at a large electrical company in Hong Kong, designed the LW1. When Paul Lam, whos the other principal in FT Audio, first heard the LW1 in Tang s system, he persuaded Fred to get it into production, and the company was formed.
The LW1 preamp is FT Audios first product. Even though its the company's premiere offering, the LW1 reeks of professional competency. The thick aluminum faceplate is anodized a tasteful gray, and the selector switch has a chunky, authoritative feel. The LW1 has five inputs, a tape-out circuit, and two sets of output RCAs. The jacks themselves are also of high quality, and they are bolted to the chassis.
Speaking of the chassis, its made from 1/8" aluminum with a really nice brushed anodized finish. Pictures dont do the LW1 justice, and it deserves top marks for its carriage work. The LW1 retails for $495 USD, and looks to be worth the asking price based on its construction quality alone.
The good news continues internally. The wiring is neat, tidy and utilizes Kimber cable, and the volume pot is a high-quality ALPS unit. There are captured steel nuts for each chassis screw, so theyre not driving into soft aluminum. This makes good sense, as steel screwed into aluminum can corrode due to the difference in metallurgical chemistry between the two metals.
Theres no power cord needed, and little exists inside the unit. Measuring 3 1/4" high by 8 1/4" wide by 8 1/2" deep and weighing just over three pounds, the LW1 is fairly compact, but not so insubstantial that thick interconnects make it wheelie.
According to FT Audio, the LW1 contains an impedance-matching circuit called the X-coupler, which gives it the ability to look at the source, volume control, and the amplifier as a complete package. Reportedly, the actual load impedance of the source is the X-coupler and the amplifier input impedance. The actual source impedance of the amp is the source and the X-coupler. The X-coupler is designed for a wide range of combinations and can drive amplifier loads as low as 10k ohms. This, in theory, should help reduce the shift in tonal balance that results from the changes in impedance caused by the varying positions of the volume control.
The LW1 replaced my Sonic Frontiers SFL-2, and so drove my EAR 509 tube mono amps. I also tried the LW1 with the Audio Aero Transtrac amp. The sources were my Roksan Xerxes/Artemiz/Shiraz turntable via a Sonic Frontiers SFP-1 Signature phono stage, and a Toshiba DVD player driving either a Melior Bidat or an Audio Aero Prima DAC. I also drove the LW1 with my Rotel RCD 975 CD player. Cables were Acoustic Zen Matrix Reference and Satori. The interconnects between the LW1 and the EARs were 2 1/2 meters in length.
Speakers alternated between my Hales Transcendence Vs and Tannoy TD10s, the latter of which I received early in the review period. These formidable transducers are at least 3dB more sensitive than my Hales, and this simple change in components highlighted just how sensitive passive preamps can be to system interaction. This small increase in sensitivity (coupled with the very high input sensitivity of my EAR509s) forced me to use less than the initial quarter of the volume knobs travel, as opposed to the almost halfway setting that I was using with the Hales. The already slightly lean lower midrange of the Tannoys became even more so, as I was unable to forge ahead to the halfway level without risking an embolism from the extreme SPLs. Switching back to my SFL-2 preamp restored the missing midrange to the great Scottish beasties. It appears that while the X-coupler may well help with impedance-matching issues, it doesnt totally eradicate them at the very bottom of the volume controls travel. Id imagine, though, that with the majority of systems this effect wouldnt be noticeable
Part of the way through the review I inserted a Toshiba DVD player into the system so that I could watch movies and use my stereo for the audio track. I was pleased to find absolutely no lack of bass or dynamics. I expected the mass-market Toshiba to suffer in this regard as it has a puny little power supply thats rather current-challenged in comparison to the other much more expensive sources that Id been using, and I figured this would be a worst-case scenario for the LW1. Thats one more torpedoed preconception.
As I say in just about every review I write, its all about system matching, and therefore you must audition equipment in your system. Unfortunately for you, the prospective purchaser, and for the desirability of repeatable results, this is much more important with a unit of the LW1s nature. Fortunately, FT Audio provides a 30-day money-back guarantee should the LW1 not work out in your home, so at the worst youll only be out the shipping costs.
With my spider-sense tingling, I hooked up the LW1 and lowered the tonearm onto the first record. My initial impression was that the LW1 sounded darned good -- much better than I had expected -- but a tad bright. However, the more I listened to the LW1 the more I realized that it wasnt adding anything in the way of brightness to the sound. Rather, in a subtle way its sound was not as dark as Id become accustomed to.
Neutral and truthful, the LW1 tells it like it is. As a result, this means that you wont get any added sweeteners. Should the recording be brutally forward, thats how youll get it played back. If the recording is thin, youll end up wasting away. When all is right, though, youll revel in the full, unedited glory of the music.
Of course, theres always the risk of lessened bass response with passive preamps. This, in effect, can highlight the mids and highs, which might perhaps explain the light and glory that many people associate with passives. So I was on my guard. There was no way that the LW1 was gonna trick me.
Sure enough the LW1 can be just a bit lightweight in the bottom end, but in a way that doesnt detract from the music. The bass could go from a touch thin at the very bottom of the volume knobs travel to satisfyingly accurate anywhere past that point. This effect was very slight, but noticeable nonetheless. As a result, I found myself playing music a bit louder than I would normally, as it was at this raised level where the bass integrated fully with the mids and highs.
But dont get me wrong! I enjoyed playing the LW1 at these levels. Space Groove by Projekt 2 [Discipline Global Mobile DGM9801] demands to be played at fairly loud levels, and the LW1 prompted me to throttle it up even more. Projekt 2 consists of Robert Fripp, Trey Gunn and Adrian Belew getting down in a slick, sparse, groove-based jam session. Fripps guitar has a biting edge with reverberant trails that go on forever, yet remain razor sharp. If the LW1 had added any brightness, that guitar would have been intolerable at the high SPLs that I was generating. The bass integrated beautifully at this increased level, and the guitar had a sizzling tone that made me imagine that I could see the strings vibrating. It sounded -- dare I say it? -- live.
The bass in the Projekt 2 disc is deep and authoritative with the right system, but can easily end up sounding boomy and overpowering if a component adds any slop into the mix. Perhaps due to its very slightly lean balance, the LW1 turned out to be just outstanding in this regard.
There was a sense of harmonic rightness about the LW1 that brought me to the conclusion that lean just doesnt tell the whole story. Cowboy Junkies The Trinity Session [Latent Latex 5] is audiophile cocaine, and it just screams to be pulled out and played every once in a while (just make sure that its the Latent pressing -- the RCA version is strident and harsh). On "Mining for Gold," the hall ambience thats present before the music starts had the requisite depth and dimensionality. This low-frequency rumble helps define the depth and size of the hall, and the LW1 did nothing to mask or diminish it. In fact, the LW1s complete absence of any sort of noise accentuated this feeling of spaciousness. Dearest Margos voice was full and breathy. As near as I could tell, there were no artifacts added to her rich contralto that could even slightly be described as colorations.
On the song that follows, "Misguided Angel," the dynamic attack and snap of the guitar was stunningly rendered, but not at the expense of the harmonic richness that underlies it (a true balancing act, this). Trinity Session perfectly captures the underlying nature of the LW1: nothing added, nothing taken away. In my system, in my room, this preamp was about as truthful as it is possible to get.
You cant handle the truth!
Over the past five years Ive had an enduring romantic relationship with my Sonic Frontiers SFL-2 preamp, which originally retailed for $3795. Bristling with tubes, the SFL-2 presents tons of detail, the bass is strong and tight, and the very slight tube softening helps smooth out the rough edges on crappy recordings. Add in imaging that goes back a city block, and Ive never felt the need to two-time.
I kept vacillating between two views of the LW1. "Its lean," Id think at times. "Rich and filling" would be my verdict with other recordings. I eventually came to the conclusion that the LW1 is exceptionally neutral. My SFL-2, in comparison, adds a very slight mellowness to the sound. This trait isnt of the vintage, misty-tube-sparkle nature. Rather, its as if some of the harsh edges have been slightly rounded, but not at the expense of detail and top-end extension (although there is just a touch of homogenization). On most recordings this results in sound thats exceptionally easy to listen to, yet detailed at the same time.
Ive come to the realization that in order to be a real man, I have to like and understand Mahler, so Im trying, Im trying. The Fifth Symphony [Phillips 422 355-2] is an incredibly dense recording, made even more richly textured by the (to me) dissonant melodies and constantly shifting textures. It takes a high-resolution system to make sense of the almost fractal divergences within this piece, and the LW1 helped me to dissect each instrument and place every musician in 3-D space. Imaging with the LW1 was crystalline. Image size seemed correct, and the space between instruments was greater than I was used to. The SFL-2, on the other hand, encapsulated the instruments in a thin haze while still managing to keep them distinct. On this recording I failed to notice any tonal shenanigans regardless of where the LW1s volume control sat.
Via the LW1, I was more conscious of individual musicians and how they were contributing to the music. With the SFL-2 routing the signal, I tended to listen to the entire piece as a whole. This tendency was very slight. The LW1 was not trounced by the formidable, two-chassis, reference-quality SFL-2. Id have to say that it was basically a fair fight that would come down to a judges split decision, and may end up in a draw.
One area where the LW1 nosed ahead of the SFL-2 was in what I call the "look up" factor. I often read while Im listening, and if a component change causes my attention to be involuntarily dragged away from a good book, then its doing something right. The superb dynamics, rhythmic pace, delineation of instruments in space, and absolutely dead-silent operation repeatedly blindsided me in the middle of the best novel that Ive read in the last decade (Cryptonomicon by Neal Stephenson).
Whos this thing for?
Throughout this review Ive summarized what the LW1 does. In some ways, its best characterized by what it doesnt do. In my system it doesnt smear or occlude images in any way, nor does it restrict dynamics. It isnt shy on bass or treble and it isnt bright, sharp or aggressive; its an exceptionally neutral preamplifier and a great bargain. Perhaps the best indicator of value is that I was quite happy using the LW1 in a system with the cheapest interconnect being twice its price.
And maybe you dont actually need an active preamp. If a unit such as the LW1 fits synergistically into your system, you could end up saving a bundle of cash that would be better spent elsewhere, and you'd still get world-class sound. While the LW1 might not be compatible with your gear, its just as likely that itll work really well. If it does, youll be in for a treat.
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