I had great opportunity and compare 3 amps.
Wells audio HeadTrip 3 lv2, Niimbus US5 pro, cen.grand i9-906 Silver Fox.
HT is THE stage champion without any doubts, it is both wide and deep, very 3-dimensional, everything is neatly lined up around the head.
SF is like HT in width, but lose to other 2 amps in depth. US5 is deep and very good layered, but same time narrower than the other two (US5 builds quite tightly without compromising positioning).
HT is better in transparency, timber, details and resolution. Excellent, simply excellent micro and macro dynamics. Bass impact and hardness (elasticity) the best I've ever heard, it would seem that this is the best transistor, but, probably, it is already the best in terms of versatility, but it has its own but... The most neutral, almost dead neutral yet very musical.
US5 has the blackest background, which also catches the eye and gives a very noticeable effect.
Let's talk on "grey zones" of amps
- SF has that weight of notes, top end air, transparency and good detail retrieval. Top end is somewhat bright, low end is massive and thick, mids are full. I never faced something similar sounding. It's almost everything and now. Yes I'd like to have more depth and hardness on lows (like HT) with texture of HT and US5. SF is smooth, very smooth sounding amp.
- US5 is dense, weighted and most dark sounding with sparky top end. It has lower transparency and detail retrieval than HT. I want to say it has matte sound without gloss.
- HT is very punchy, hard hitting with amazing resolution and separation. From the beginning I thought it has not so much weight of notes and sounds bright but after burn in SQ become darker with much more meat on bones.
overview
from dark to bright US5-HT-SF
punch from better to worst HT-US5-SF
details/resolution from better level to lower HT-US5=SF (last two almost the same result)
power - all 3 can drive anything...
dimensions from smaller to bigger US5-SF-HT
musicality (liquid sound) from best to worst SF=HT-US5. That doesn't mean US5 is dry to analytical, it just on 3rd place
Any of these amp can be end-game.
In the end I sold SF and quite sure HT3 lv2 can be the one and only.
P.S. my equipment: PS audio DS mk2, aurender n200, snorry trion headphones.