I still have a Super PAS 3 that saw regular use until about 5 years ago. Now it and a ST70 are in rotation with two tube integrated amps. I have tried several PAS modifications over the years, and found the Super PAS 3 to provide the best sound.
If you’re interested in the gory details, I got my first new PAS around 1976 after hearing a modified Dynaco system at the CES in Chicago that year with Fulton/FMI speakers (my first exposure to truly high-fidelity sound). I built the PAS with modification plans from a place in San Diego called Audio Dimensions, and thought it sounded great. Then I put together a system for a friend. He didn’t want to budget for the fancy parts from Audio Dimensions, so I just tweaked the RIAA, and deleted the tone controls and hi filter. You probably know what happened next. His preamp sounded better than mine. Learning experience: modified is not synonymous with improved! Turns out the Audio Dimensions mod was basically to change all the circuit values to those of the ARC SP3A-1, but of course without the cathode followers. That made it sound relatively dark and slow in comparison to the less-modified PAS, much like a real SP3A-1. So, out with the Audio Dimensions circuit, and in with the circuit like my friend’s unit. I stayed with that for many years. My chief complaint was a slightly nasal quality to the sound that I thought was the fault of my speakers but turns out was the linestage. In a second PAS, I built Norman Koren’s circuit when it was published in Audio Amateur, I think around early to mid 90s. It was a good sounding circuit that eliminated that nasal quality, but overall was a little veiled, maybe due to the cathode followers, I don’t know. But it put your listening perspective in the back half of the hall rather than the front half, so to speak. Not long after that, I decided to go with the AVA circuit, probably because I had begun to question my ST70 mods, and implemented Frank’s 1982 Audio Basics article on an ST70 with great results. The Super PAS 3 proved superior to the Koren mods, and that annoying nasal quality was still gone. I have tried one other circuit since that time, a cascode linestage from an article by Bruce Rozenblit in Glass Audio. It’s good, but not as good as the Super PAS 3 in my opinion. The only other preamp that I have compared directly to the Super PAS 3 is a McIntosh C20 that I owned. Other than the cool factor, it’s not as good, so I sold it.
I have not had the pleasure of hearing any of the newest AVA gear, and I am sure they are amazing, but that doesn’t make the Super PAS 3 any less satisfying, especially if your reference is live music. Hope something in this long tome was useful!
Best regards,
Mike