Burson op-amps are solid-state. I've already place in my first post this link:
https://www.head-fi.org/threads/bur...ssion-and-reviews.854912/page-7#post-13711554, so everyone here can understand what's inside a V6 generation. The newer and smaller V7 Pro SS
op-amps are biased in Class A, same as the power output stage.
Here on Head-Fi folks started to talk about the Burson Solid State op-amps since generation 4...or perhaps even before of that. I started testing these op-amps since gen. 5, so feel free to search within Head-Fi database some more interesting readings about them.
As you can see from my earlier measurements, harmonics profile is a bit different from one op-amp to another, so some golden-ears persons might hear different nuances of the music, most of these being usually very subtle. I'll see if I'll find in my shelves a few OPA1602 to try them out inside the Soloist GT, as these are the best measuring BJT-input op-amps I've ever seen.
I myself use at home -120 dB THD+N DAC and -150 dB ADC+APU (used for audio measurements) because I like to own high performance audio equipment, but that doesn't stops me to try other sort of audio equipment that in A/B tests might show different nuances of the voices, cymbals etc. I am an objectivist that looks for proofs when audio differences appears, so this is why I perform such audio measurements most of the times.
I remember a few years back how I managed to lower the background noise of my Objective2 headamp by swapping the default NJM2068 op-amp with a Burson V5, although on the paper the default NJM2608 or the later OPA1602 are more performant than the V5, so sometimes the final output sound might not match datasheets perfectly, so listening tests and probably different ways of measurement techniques might be required.
L.E.: AFAIK, Burson op-amps are made for audio use only and are optimised for Burson audio equipment, also several head-fiers are reporting audible improvements when using them inside non-Burson devices too.
