Unfair Competition: Orchard Audio Bosc Monoblocks vs. Pass Labs XA30.8


After hearing a friend's Orchard Audio Starkrimson Integrated Amplifier in my system (https://systems.audiogon.com/systems/9074) a few weeks ago (it sounded pretty good!), I arranged to audition a pair of used Bosc $1500 monoblocks (now called Starkrimson) for close listening.  Was curious to see just how well this "distortion-free" class D amp (https://www.audiosciencereview.com/forum/index.php?attachments/orchard-audio-bosc-pdf.47492/) could replicate my beloved Pass labs class A beast costing >$6000 new.  Close listening was done after several days of casual listening/break-in.

Bosc - The Good:
- Wide and tall soundstage
- Convincing central image
- Extremely quiet -- less baseline hiss than the Pass
- Fast transients
- Excellent instrument decay/echo
- Obviously more energy and space efficient

Bosc - The Not as Good
- Lacked soundstage depth/separation
- Less vibrant and engaging, lacking difficult-to-articulate "magic" of the Pass
- Inconsistent bass performance, some tracks sounded firmer and tighter, others weaker than the Pass
- "Flat sounding" with less fleshed-out midrange

After having the Bosc in my system for a few days and listening to nothing but that with a variety of music, I would have been very happy to keep it for the long-term.  It was only after A/B with my Pass that I realized what I was missing.  

Not a fair comparison dollar-wise, but I was, perhaps naively, prepared to be convinced the Bosc could go head to head.  A nice reminder of what I enjoy about the Pass in my system, though.  How to measure these qualities, though?
redwoodaudio

This is getting interesting. After hearing the more open top octave of the Starkrimson monos compared to my old Aleph 2 monos...with NO compromise in harmonic richness nor soundstage depth, I sold the Alephs, their Nordost SPM 8' cables, as well Red Dawn pre/pow ICs, deciding to make my olwn solid pure silver 1' links from the Starks to my Parsifal Encores...as well new ICs and Parsifal jumpers.  The reduction in smear and sandiness on brush strokes with the Ag links is real. I remporarily had to use a Stark Stereo Ultra unit, reverting to old AudioQuest speaker cables, and indeed the top octave res dropped. Reinserting the Stark monos with 1' Ag cables restored the improved res. NOT expectation bias, as I've had enough swaps to be not experiencing placebo.  The point is that the clearer top octrave res of the modern Starks is simply more revealing of cables and upstream sources...for good or bad. Even though it';; probably be less forgiving of a larger portion of mediocre recordings, I'm willing to live with that to get a "fresher", VERY realistic presentation. I attend many live classical and acoustic performances, and the Starks simply bring me closer than the old Alephs.

NOW, that's not to say that Nelson's NEWER designs aren't more resolving...and maybe less "dark" sounding indeed, as so many love his XA25, for example, as well the big boys.  Given that the Starks only consume 8w idle means they're on 24/7, without the "juicy" (300w idle each!) i hour warmup the Alephs required. Class D with GaN is indeed a brave new world....

The thread-head's comment that the Stark's midrange disn't seem as fleshed out as his Pass amp is intriguing. I wonder if that Class A "magic" or the possibility that because the Starks sound FLATTER that one hears less midrange because there's no top octave perceived droop (or darkness?). Which Pass amp, by the way? Foilks tell me the old Alephs were wonderful...but not as open up top. That's my perspective now too.

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