Ok here’s my quick review:
Belles 350a Reference (in comparison to the VK-500)
The Belles is more detailed and clearer layering more apparent. Absolutely no mud but also no ‘glue’.
The amp comes off as all midrange and highs, which makes sibilants feel a bit less obtrusive, more integrated.
It’s not a ‘transportive’ amplifier, it doesn’t take you anywhere. Feels like a clean cutting surgeon in a stainless steel room, clinical and not very sexy.
Definitely a wider more holographic presentation. But not as full frequency as the VK-500. The Belles is missing that foundational low end. Perhaps it is too dampened...?
Even at lower volumes still very clear and forward. Maybe a bit better dynamics in the upper mids/low highs. Lot of energy here makes the amp feel a bit faster than the VK-500. This is the only area of real excitement in this amp—think Baba Oriley rebellious guitar strums really jumping.
When you aren’t being pushed always by the aggressive upper mids it’s very easy to hear into any mix. There is more air than the VK-500 with some nice specificity of instrument placement.
...I was hoping the Belles would replace my VK-500. The VK-500 is a beast of an amp, at about 110 lbs it is the largest heaviest machine I have owned, not including automobiles. But the 500 makes music—warm, rich, intensely impactful in the lows, setting up an incredible foundation for the rest of the soundscape to be intoxicating and inviting. It’s rare to stop thinking about the gear and to be swept away by the music. The VK-500 achieves this.
In summation, the Belles would be extremely useful as an ‘in-studio’ amplifier. With silk dome tweeters and a more mellow, woody speaker, it would promote effortless appreciation of any mix.