Hello everyone,
I have and love my Thresholds: 400A and SL-10 pre, hoverer, I just can't live without future plan. So my question is: What should be a next future upgrade from 400A? Should it be a S200/300 or save some money and buy Aleph or x150? My budget is tight so I won't be able to afford x.5 series 🙁. How x150s compare to Aleph and why Mr. Pass moved from class A to symmetric p-p x series, is it improvement?
I would appreciate any comments and will be glad to give you some more input parameters if needed. Thanks!
I have and love my Thresholds: 400A and SL-10 pre, hoverer, I just can't live without future plan. So my question is: What should be a next future upgrade from 400A? Should it be a S200/300 or save some money and buy Aleph or x150? My budget is tight so I won't be able to afford x.5 series 🙁. How x150s compare to Aleph and why Mr. Pass moved from class A to symmetric p-p x series, is it improvement?
I would appreciate any comments and will be glad to give you some more input parameters if needed. Thanks!
I bet you thought that getting good Class A performance without a feedback loop was exotic, difficult, and expensive.
Not if you Do it Yourself.
Not if you Do it Yourself.

OK , besides DIY , have you any possibility to listen possible candidates ?
preferably in your environment ....
preferably in your environment ....
OK , besides DIY , have you any possibility to listen possible candidates ?
preferably in your environment ....
I would say NO, but I will try! How about Threshold S-series S200/300 will it be an upgrade from 400A(I've recapped it)?
presuming that both are capable to drive your speakers in your room with your ears ...... dunno

you're asking too much in forum - at least for difference between Treshold ; for my knowledge they're still on same side of coin
are PL amps on other side of coin - enough - to justify price difference - I would say yes , but only you can measure value of that
sorry .... ;(

you're asking too much in forum - at least for difference between Treshold ; for my knowledge they're still on same side of coin
are PL amps on other side of coin - enough - to justify price difference - I would say yes , but only you can measure value of that
sorry .... ;(
Maybe thats a good idea, what Aleph you can recommend? I have infinity kappa 8.1 speakers now, so they benefits from more power and high current. Thanks!
with 6 Ohms and 89db/2V83 you need either a biiig Aleph , or smaller X amp
maybe Aleph 5 as smallest you can use
FYI - Aleph 5 is 60W/8R/ch
Aleph 4 is 100W/8R/ch
having no experience with your Infinity sps , I can't tell more
maybe Aleph 5 as smallest you can use
FYI - Aleph 5 is 60W/8R/ch
Aleph 4 is 100W/8R/ch
having no experience with your Infinity sps , I can't tell more
all those were Pass Labs products , later given by Mighty Papa to DIY community , for joy and pleasure


why Mr. Pass moved from class A to symmetric p-p x series?
Abandon Class A? Hahahahahahahaaaaa........

Mr. Pass, it was not a statement, but question! 🙂 I read that x series is AB class but Aleph was class A. Maybe I am wrong, please correct me. What do you think if biamp Aleph 4(mid/top) with 400A(bottom)?
With minor surgery and terminals added, could even go tri-amped.
http://www.infinity-classics.de/technik/manuals/Kappa_8.1_technical_sheet.pdf
http://www.infinity-classics.de/technik/manuals/Kappa_8.1_technical_sheet.pdf
Ok, I am really got excited on DIY Aleph 4! As I mentioned before it is not a best time financially for me, would you be willing to help me just estimate how much this project can cost? (or these types of project). Thanks!
Oh, btw, I have a question to Mr. Pass or maybe someone else can answer:
I can hold my hand on a heatsink of my 400A for 3 seconds when it is warmed up, is ok or it is too hot for this amp and I need to adjust the bias? (do not want to fry outputs)
I can hold my hand on a heatsink of my 400A for 3 seconds when it is warmed up, is ok or it is too hot for this amp and I need to adjust the bias? (do not want to fry outputs)
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I forgot - 50 is OK, 55 is too much - considering that's winter now
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