These two amplifiers are children from the same BAT family and have similar BAT sound qualities. The 125W per channel VK-220 ($3000) and the 150W VK-250SE ($7000) employ mosfets in their output stages. Both amplifiers are fully balanced designs and have XLR input connections. Both amplifiers weigh 75 pounds and measure 19” wide x 6.5” high x 16” deep. They have toroidal transformers and keep their heat sinks fully inside the enclosures so there are no concerns about dealing with sharp edges during installation. And both amplifiers, like several other components from Balanced Audio Technology that have been reviewed here on 10Audio, were completely reliable and trouble-free even after many hot-plug cable changes and on-off cycles which are a normal part of the review process.
Neither amplifier offers a lot of appeal to those prospective owners who like their components to be visually imposing. For eye-candy, you should shop – and pay dearly for the privilege – elsewhere. I think they are understated but elegant, especially the more sculptured appearance of the VK-250SE which is available with either an all-black face or BAT’s more common brushed aluminum center section with black “wings” on the very nicely finished front panels. The VK-220 sports an all-black faceplate as standard. I appreciated the quality construction and excellent fit of the top covers on both models. Most of our audio systems have the components occupying a rack which is situated between the speakers and the listener faces the components. Bright LEDs and other lights can be an intrusion into the listening experience. I welcomed the muted blue LED power indicators. Thank you, BAT!
Both “VK” (for Victor Khomenko, who holds a Master's degree in electronics and physics from the Leningrad Polytechnic Institute) amplifiers have excellent timing that moves the music forward in a cohesive and natural manner. The soundstage is very believable with excellent depth and lateral placement of performers. The VK-250SE is just a bit better than the VK-220 in this regard. The feeling of dynamic power and control always seemed to be greater than the specified power ratings would suggest. This ability to deliver a lot of power has a benefit in the soundstage where it was noticed that no matter the loudness, performers stayed in their positions and did not wander forward or merge with adjacent musicians as the volume increases as is sometimes heard from competitive products.
The sense of speed of the amplifier, which lets the amplifier deliver a note to the speakers and then move on to the next sound without overhang or blurring, was never an issue. The amplifiers never seemed to be straining to deliver instant power as required. There was plenty of snap and punch when required, although in the VK-220, the sense of dynamic slam was slightly better in the lower frequencies than in the upper frequencies.
This is a good time to talk a bit about comparisons and how unfair they can be to components that visit for a review. I have high standards, both in what I require from my ever-changing system to meet the all-important Zen Test, and how each component is judged in comparison to other gear which may be in-house during the review process. The Zen Test ignores cost, technology, and all other product features and focuses solely on sound quality as it relates to listening enjoyment. A $1,000 component is evaluated on exactly the same scale as one which costs $10,000. Fair or not, this is the arena we play in here at 10 Audio. The primary comparison amplifier was the wonderful Manley Neo-Classic 250. This mono pair of EL34 tube amps delivers 250 Watts in tetrode mode, which is where all my listening occurs. Many audiophiles have a preconceived idea that the EL34 epitomizes stereotypical tube sound. I have heard EL34 amps that are overly sweet and lack extension in the bass and treble (which describes the Manley amps in triode mode), but the Manley amps in tetrode mode completely avoid these characteristics and sound very dynamic, have powerful and detailed bass, and an extended and detailed treble region. The Manley’s bass may not be quite as tight or focused as we often hear from typical solid-state amplifiers, but the overall dynamic power and resolution are outstanding. These amplifiers are easily world-class, reference-level components.
Compared to the Neo-Classic 250s, the VK-220 amplifier exhibited a noticeable lack of high frequency purity. Treble extension is slightly reticent, which may be a trade-off to somewhat mute the character of the transistor heart of these amplifiers. However, they did not sound noticeably dark or closed in. There was a definite layer of solid stage “texture” that removed the feeling of freedom from distortion and air that the Manleys, and many other tube and better solid-state amplifiers, easily deliver. Do you remember Snoopy from the Charlie Brown comics and the way he danced when he was happy? That sense of openness and joy is largely missing from the treble presentation of the VK-220. For the VK-250SE, much of that openness is present, but this character definitely runs in the family. For the VK-220, this “transistor effect” includes the midrange, too. The treble quality is credible for either amp – and quite a bit better with the VK-250SE than the VK-220, but I would not recommend either model if your acceptable standard is based on your preference for the openness, freedom from electronic artifacts, and purity of tone that we usually get from tubes.
I also compared the VK-250SE to a Pass X250.5. The Pass is one of the world’s best 15 Watt amplifiers. Above 15 Watts, its output mode changes from pure Class A to AB and the sound becomes less sweet, resolved, and smooth. At higher levels, the VK-250SE and X250.5 sounded more similar, although the bass from the Pass amp was a bit more powerful and detailed. Late in the review period, a Halcro MC20, which is a 400W Class D stereo amplifier, made an impressive showing with an extremely dynamic performance that was utterly free from the upper frequency deficiencies heard from either BAT product, although this same range was not quite as rich and voluptuous as offered by the Manleys.
The VK-250SE was enjoyable for longer listening sessions, and it seemed to make the relative advantage of vinyl – greater resolution and tonal purity – over CD the preferred medium by a larger margin than I experience with the Manley amplifiers. One standout CD was Sailing to Philadelphia, and the title song put both Mark Knopfler’s and James Taylor’s voices right there in my listening room. The midrange of the VK-250SE is excellent, both in resolution and in being a coherent partner to adjacent frequencies. This character enabled this particular CD to sound rewarding and enjoyable.
The stock power cord worked very well and was apparently chosen with great care and is not just a “throw-away” cable. Its sound complements the amplifier and helps the lower midrange add some welcome weight and power. The sonic results were better with an Audience PowerChord E with which the VK-250SE had more openness in the upper frequencies, with more metallic sheen heard from cymbals. As with most audio components, experimentation with power cords is recommended to extract the most performance and tune the sound to the rest of your SRT: system, room and tastes.
The results of my listening sessions were similar for both amplifiers, although the VK-250SE is quite a bit better sounding than the less expensive model. I dutifully listened to each amplifier at length, took extensive notes and tried different speakers, sources and cables. After a couple of record sides with the VK-220, or around two to three hours listening to the VK-250SE, I would look at the Manleys sitting there, disconnected and cold, and usually decide that it was worth the wait for them to warm up to really enjoy listening to music for the remainder of the evening.
...VK-220: 6 LPs
...VK-250SE: 7.5 LPs
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