Balanced Audio Technology (BAT) is a decades old company specializing in, you guessed it, balanced audio components. They have produced a long line of vacuum tube and solid-state preamplifiers and amplifiers, phono preamplifiers and, more recently, digital converters. The BAT VK-300xSE integrated amplifier was reviewed here in 2004, and the VK-31SE tube preamp was reviewed here in 2005. BAT has received numerous “best of” awards over the years for their excellent sounding and innovative products.
There has been a convergence in the sound quality of vacuum tube and solid-state components which has been happening gradually since solid-state gear exploded into the marketplace in the 1960s. Over the past few years, this convergence seems to have entered a terminal phase because some solid-state components meet or exceed the highly desired sonic strengths of tube gear. This is relevant for this review not only to showcase a long-gestating technology, but also to give audio consumers the option to not rely on any particular technology when considering a system change. Tube rollers will find little to do here.
The BAT VK-43SE stereo analog line stage solid-state preamplifier, $8995, was requested for this review to help ascertain the maturity of solid-state technology and to hear the latest top-of-the-line solid-state preamplifier from BAT. Steve Bednarski, the General Manager of BAT, was very kind and accommodating in their participation with this review. From the BAT description of this model:
“Combining BAT’s trademark high-current Unistage topology with the transformer-coupled outputs anchoring all Balanced Audio Technology Special Edition preamplifiers, VK-43SE establishes a new performance benchmark. Upgraded output transformers work in conjunction with a high-bias symmetrical N-channel Unistage gain block. Fully balanced dual-mono construction and more than 55,000uF of power-supply capacitance yield instantaneous response to the most demanding signal requirements. Second-generation oil-filled capacitors provide increased purity to the elegant Unistage circuit, completing BAT’s new flagship solid-state preamplifier.”
The VK-43SE includes a proprietary electronic shunt volume attenuator that has 140 steps of 0.5dB resolution. Most listening was with the volume control in the 30 to 60 range, and the very fine 0.5 dB adjustments were a delight to be able to get the volume just right, although the change from 30 to 60 takes several seconds. The large volume adjustment range practically guarantees that the VK-43SE will be compatible with any power amplifier on the planet. Also available is the optional, internal VK-P20 phono module. 10 Audio requested the line stage only, so the phono module add-in was not tested here. There are 3 balanced analog XLR inputs and 2 unbalanced RCA inputs. The 2 outputs are both on XLRs, and the tape output is RCA. There is no trigger input or output. All features are controllable on the excellent metal remote control, including balance, mute and phase adjustments. The dimmable front panel display has large lettering and can be set with custom input names, such as “LP” instead of input 1. A 5 year warranty is standard. The user interface for setup and regular operation is superb.
Other components on hand during the audition include a VPI Aries 3 turntable with a Kuzma 4-Point tonearm, ZYX UNIverse Premium and Miyajima Madake moving coil cartridges; B.M.C. MCCI ULN and Pass Labs XP-25 phono preamplifiers; custom Windows 10 music computer running JRiver Media Center; Wyred 4 Sound DAC 2v2SE 10th Anniversary and Bryston BDA-3 DA converters; RME ADI-2 Pro AD/DA converter with external power supply; Pass Labs XP-22 and Wyred 4 Sound STP-SE Stage 2 preamplifiers; Wyred 4 Sound ST-750 LE, Valvet E2, and Pass Labs XA30.8 power amplifiers; Focal Sopra 1 loudspeakers with the lowest few Hertz supplied by a pair of JL Audio e110 subwoofers, and Focal Chorus 714 loudspeakers borrowed from the HT system. The audio cabling is Audioquest WEL Signature and Mogami interconnects and speaker cables. USB cables are Straight Wire USB-F. Power cords include my DIY power cord and Straight Wire Pro Thunder. Power protection and purification are provided by a PS Audio Dectet for the preamplifiers and source components, and a PS Audio Quintet for the power amplifiers. The Quintet provides remote turn-on and -off of power amplifiers that lack a 12V remote trigger.
After the initial 300 hour break-in period, a wonderfully rich and human sounding midrange is quickly apparent. There is very fine resolution across the octaves with an understanding that the final voicing of the preamp was honored by designers and engineers who hold excellent vacuum tube sound in high regard. What does this mean, exactly? The answer to that question is the primary conclusion of this review.
Solid-state components are usually noted for their powerful, controlled bass and extension into the uppermost treble. Tube gear is especially valued for the rich harmonic density in the midrange and lower treble. The VK-43SE blends these two characters very well. The vocal range bears a very strong resemblance to vacuum tube-type quality, and the bass is very powerful ‘solid-state’ sound.
The bass range is very high quality with the highly desired tight, fast high resolution which often provides that “punch in the gut”, shake the foundation slam and power, with outstanding resolution. Bass notes have excellent depth and present the vibration of individual strings clearly. The overall bass character is not the dry and lifeless type that was prevalent with older solid state. Think of the best tube bass you have ever heard, and then add in warp speed and thunderous dynamic power down low, and you will understand the bass quality of this BAT preamp.
The midrange is special. Both male and female vocals are presented with a warm richness that gives body and depth to all singers. Instruments have wonderfully complete fundamental tones with a natural harmonic accompaniment in the lower treble. There is no hash, grain, grit or other bothersome distortions in the very tube-like midrange. This really is a wonderful preamplifier, spectacular when listening to music with singers, from one to one-hundred voices. All are presented with clarity that makes “seeing” individual performers on a large 3-D performance stage a simple task.
Mark Knopfler’s vocals on “Romeo and Juliet” from the Dire Straits album Making Movies is tremendously vibrant and textured. Bonnie Raitt, especially on her Luck of the Draw LP, also sounds wonderfully present and alive. These two examples are not unique. All vocals are presented beautifully.
The upper treble is very tube like and similar to a Mullard 12AU7 which is warmer and more focused on the midrange than, for example, a Telefunken tube might be. The extension into the upper treble is a bit shelved-down. All the detail and resolution which are on the recording are present with the VK-43SE, just relatively recessed compared to the lower treble. Many listeners will find this balance to be perfect, in the way some listeners find the sound of solid-state preamps to be bright and forward. It is all about system synergy, with you being part of the system.
The soundstage can be huge, with a lot of space and atmosphere, as the recording demands. This is one of the preamp’s many strengths. The center image is solid, 3 dimensional and focused. Instruments are delivered with excellent placement on a well-defined sound stage, with superior depth and height. Each performer is clearly placed, with excellent separation from adjacent musicians, although with not quite the sharper outlines provided by the Pass Labs XP-22 preamp. Especially noteworthy is the perception of depth into the farthest reaches of the performance stage. Many components are unable to dig into the sound stage as deeply.
The most important difference between the VK-43SE, the Pass Labs XP-22 ($9000), and the Wyred 4 Sound STP-SE Stage 2 ($3749) preamplifiers is in their mid-upper treble presentation, specifically linearity (extension), when compared to bypassed. Bypassing the preamplifier simply involves connecting the source cable’s XLR male connector directly to the amplifier cable’s female XLR connector, and controlling volume in the DAC or software – with great care and planning for volume control. (Sorry vinyl. For this test, you’re on the bench.) In the order of how each preamplifier’s sound in the upper frequencies compares to the sound of the direct, bypassed configuration, the Wyred 4 Sound preamp is “dead nuts” right there, followed by the XP-22, with the VK-43SE bringing up the rear position. This is voicing. The quality is there for all three preamplifiers, only the presentation is different. In a more direct comparison, the VK-43SE has greater purity and freedom from an electronic signature than the XP-22.
The entire preamplifier sounds better than some individual tubes in my experience. This is not the early Sovtek 6922 hard and aggressive type of sound. On the contrary, an owner will be rewarded with a tube-like overall character, one that could be the final result after all the tube swapping we often do to a component with vacuum tubes. Here, however, you would forego that effort and expense in the initial selection, and again later when the tubes would need replacing. There are no tubes to bother with in this preamplifier, but you get that level of sound quality.
Go tubeless! The BAT VK-43SE can take you there. Due to the powerful bass and clear treble, this preamp is definitely more linear and accurate than many all-tube preamps. You get the richness and control that could cause you to re-evaluate the need for tubes. For the often-preferred combination of a tube preamp with a solid-state power amplifier, the VK-43SE preamp will work splendidly and is highly recommended. The VK-43SE and the Pass XA30.8 amplifier is a fine marriage.
Vacuum tubes have been mentioned extensively in this review because the similarity of this preamp’s character to tube gear is unmistakable. You are encouraged to audition this preamp if you enjoy the rich, saturated midrange and grain-free treble of vacuum tubes but want better bass and would like to banish all tube maintenance issues. This preamp just might convince you that vacuum tubes are not required for good sound, and that the older technology is slowly but surely becoming passé. The wonderful sound qualities of the BAT VK-43SE preamplifier will find a perfect place in many fine audio systems.
Overall Rating: 9.5 LPs
This review would not have been possible without the kind and generous support of Steve Bednarski of Balanced Audio Technology. Thank you, Steve!
Link to manufacturer: Balanced Audio Technology