VTL MB 175 Signature monoblock power amplifier Page 5

You can have that by shifting to triode operation at a flick of the front-panel switch (after turning the amps off!). I tried it but didn't end up liking it very much. Ninety watts sounded anemic to me, with sloppier bass and compressed dynamics. Rock music got stuck in the mud, solo violin sounded a bit more rich but too syrupy for my taste. Perhaps the amps would work better in triode mode with other, easier-to-drive loudspeakers. I preferred the taut bottom-end control, the outstanding high-frequency extension, and the overall dynamic thrust tetrode operation offered. I did all of my listening with the switches set like this.

While the VTL 175s lack the physical sex appeal of some other tube amplifiers out there, they offer sufficient power to drive small- to medium-size, efficient, small-woofered speakers at a more than reasonable price point. Add outstanding extension and control at the frequency extremes, low noise, and low audible distortion, and you have a prescription for long-term musical satisfaction.

Conclusion
The 807-driven, medium-power VTL MB 175 monoblock offers an outstanding combination of sonic and technical virtues at a more than reasonable price. Over the nine months I had the pair in constant use, they required no maintenance, nor did their performance change. If you like your sound "warm and tubey," you probably won't like this amp. If you like your sound "lean, clean, and tubey," as I do, you might really like it. Mikey did. Definitely worth checking out if it's in your price range and you have appropriate transducers.

I can't wait to read the measurements to see how well they correlate with what I heard. Here's my prediction: Rated power will be 10-15% below spec, or about 160W at less than 3% THD. Frequency response will be less rolled-off on top than some other tube amplifiers, and squarewave response will also be respectable at 10kHz with good risetime and perhaps a bit of ringing, less so at 1kHz. I predict reasonably low second-harmonic distortion for a tube amp from a 50Hz sinewave only because this is not a "warm"-sounding product.

Probably foolish of me to make these kinds of predictions, but there you go. As for some of the other things TJN measures, I can wait to find out—and I can definitely wait to read about how what I'm hearing that I like is all some kind of distortion. So be it, TJN!

COMPANY INFO
VTL
4774 Murietta Street, Suite 10
Chino, CA 91710
(909) 627-5944
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