Threshold verse Pass Labs how can I justify significant price difference
I'm running currently series one Threshold S500 with the optical bias and Threshold S500 second series as a bi amp config to my JBL 4367. System sounds the way I like it no complains. Now I've been having thoughts about upgrade amps to Pass Labs 350.5 or 250.5. 250.5 would be in same power range as S500 so my question is since Pass will be priced higher how much better would it sound and is it worth to spend extra $$? does 250.5 will make so much difference that there is no sense to go up to 350.5? or the only way to get any significant upgrade is to go for 2 of 350.5 and would it be so much better sound than my Thresholds I could justify spending extra $7K!
Nelson Pass seems to suggest prolonged "Class A bias" as a positive attribute. FWIW, the Threshold S Series amps were said to be "Class A biased" to 20 % of it's rated full 8 Ohm output per channel. That would suggest that your S 500's has a "Class A biased" output of 50 Watts per channel. More than the either the Pass Labs 250.5 or 350.5.
So as far as I can see, I should live alone my setup. the only reason I would even look at 350.5 is its looks and appearance. And since there is no significant difference between S series and Pass X series there is no point for me to spend money. BTW I’m aware my amps aren’t the best but I like how they sound and look and I like to stick with Pass design amps. thank you guys for your opinions
Valid point and all opinions lead me to conclusion to stop improving my setup and start enjoying it. All doe I always wanted FAT 10 both panels so I just might get it and see if on pre amp stage I could improve situation
I'd hardly say there's no significant difference between Threshold products and Pass Labs! Major differences to note: Pass Labs amps use FETs instead of BJTs, they use Su-Sy feedback, they're high bias region is single ended rather than balanced. They represent the more evolved designs of a more experienced engineer.
Unless you're using obscenely inefficient speakers, which you're not, you don't need 250+ watts. I'm listening to 91dB sensitive speakers powered by a 31 watt Pass F5. It's more power than I need. And it sounds excellent.
Sorry, not having read enough of this thread, I may be repeating something here. I owned a Threshold S500 and took a peek inside. It was impressive, 'for it's time', I will say that. As well built as it was, there was an issue with the channels being cooler than they should, which is a bias issue. My point here is that to resolve all the issues associated with getting the amp back to spec was not worth the effort. The search went on from there to find a suitable working replacement.
Yeah. They're completely different architectures with completely different gain devices and very different feedback schemes. Nelson likes to say MOSFETs are superior output devices so there's that when it comes to transistors.