OK , we need to differentiate mosfet input Alephs vs. JFet input Alephs , but I'm sure that any Aleph no good sounding - either isn't made properly , or isn't mated properly
I think we are likely "splitting hairs" on Aleph J vs F5. Both are great amps if built correctly. It is like trying to discuss which is better, a Porsche GT3 or GT4. They have their design differences, they have their similarities. You can debate all day long about the merits of each, but both are wonderful high performance machines. And I would be happy with either one. Manual gearbox and Riviera, Mexico, or Miami blue if possible.
OK , we need to differentiate mosfet input Alephs vs. JFet input Alephs , but I'm sure that any Aleph no good sounding - either isn't made properly , or isn't mated properly
Parts for an Aleph J keep appearing in my mailbox so eventually I will need to find it a mate. So Mr ZM what would you consider a proper mate? Currently I have some 88db sensitive 4" fullrangers 8 ohm (ff105wk). If I start shopping around for other speakers anything to avoid?
any speaker is good if SPL is low and you''re close to them
though , for my taste ,sissy A class amps are best when paired with bigger and efficient and sensitive drivers
choice is waste , both old SH or new ones .... but , I need to say - one must observe both efficiency and sensitivity ; explanation - high power PA speakers are efficient , but of lesser sensitivity , simply because of fact that high power demands strong and heavy motors , thus higher moving mass
so , old school drivers (low power ) are way to go
in case that you're on this side of Pond , I would advise to buy Sonido (say something as Sonido , (almost) 1,5 Way speakers by ZM , Woland Edition | Zen Mod Blog )
but , you being where you are , someone with more local knowledge must chime in
though , for my taste ,sissy A class amps are best when paired with bigger and efficient and sensitive drivers
choice is waste , both old SH or new ones .... but , I need to say - one must observe both efficiency and sensitivity ; explanation - high power PA speakers are efficient , but of lesser sensitivity , simply because of fact that high power demands strong and heavy motors , thus higher moving mass
so , old school drivers (low power ) are way to go
in case that you're on this side of Pond , I would advise to buy Sonido (say something as Sonido , (almost) 1,5 Way speakers by ZM , Woland Edition | Zen Mod Blog )
but , you being where you are , someone with more local knowledge must chime in
A friend also has AJ Mono's and an F5 that he uses on Alon Lotus SE's. I lent him an F5 while I was working on his AJ's, and he bought it from me (he wouldn't let it go...).
An Alon would make a nice choice: bi-amp using Aleph J on the open baffle top and F5 on the sealed bottom. Then future expansion to run active LP to the bottom. Let’s clone one!
J vs 30
Anyone done comparisons with Aleph J vs the older Pass models? I have a Aleph 30 that I love and am trying to decide which DIY amp to tackle for stablemate . Considered the Aleph J, but also wanting something with some different sonic character and not sure what improvements the J would provide over the 30. Essentially, I have the cash to build one amp right now and am scratching my head on which to choose. Also considering F6 and M2
OK , we need to differentiate mosfet input Alephs vs. JFet input Alephs , but I'm sure that any Aleph no good sounding - either isn't made properly , or isn't mated properly
Anyone done comparisons with Aleph J vs the older Pass models? I have a Aleph 30 that I love and am trying to decide which DIY amp to tackle for stablemate . Considered the Aleph J, but also wanting something with some different sonic character and not sure what improvements the J would provide over the 30. Essentially, I have the cash to build one amp right now and am scratching my head on which to choose. Also considering F6 and M2
Anyone done comparisons with Aleph J vs the older Pass models? I have a Aleph 30 that I love and am trying to decide which DIY amp to tackle for stablemate . Considered the Aleph J, but also wanting something with some different sonic character and not sure what improvements the J would provide over the 30. Essentially, I have the cash to build one amp right now and am scratching my head on which to choose. Also considering F6 and M2
I think the F5 would be the most "different".
I think the F5 would be the most "different".
I’ve suspected that too, but somewhat concerned about the abundance of detail and accuracy. Sounds silly to say, but not sure my room and rest of system would handle it well. I guess what I mean by different from Aleph 30 is “same, but different” or “same, but better.” 😀
if you want different , build SissySIT -for delicate and easier load , or build Babelfish M25 for more demanding load
or Babelfish J2 , for loads in between

or Babelfish J2 , for loads in between

if you want different , build SissySIT -for delicate and easier load , or build Babelfish M25 for more demanding load
or Babelfish J2 , for loads in between
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On the list. Heard that guy too is a genius

Anyone done comparisons with Aleph J vs the older Pass models? I have a Aleph 30 that I love and am trying to decide which DIY amp to tackle for stablemate . Considered the Aleph J, but also wanting something with some different sonic character and not sure what improvements the J would provide over the 30. Essentially, I have the cash to build one amp right now and am scratching my head on which to choose. Also considering F6 and M2
I have compared AJ with Pass Labs Aleph 5. Aleph 5 looks way better than my DIY AJ, but they share surprisingly the same sound signature, and I'm pretty sure that you'll not find too much difference between 30 ands J. It would be a reasonable upgrade, though. If you would pursue single ended and don't mind low wattage, I would recommend to try MOFO or L'amp.
Agree with ZM, AJ sounds great with the classic horn speakers with 15" woofers.
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I have compared AJ with Pass Labs Aleph 5. Aleph 5 looks way better than my DIY AJ, but they share surprisingly the same sound signature, and I'm pretty sure that you'll not find too much difference between 30 ands J. It would be a reasonable upgrade, though. If you would pursue single ended and don't mind low wattage, I would recommend to try MOFO or L'amp.
Agree with ZM, AJ sounds great with the classic horn speakers with 15" woofers.
Thanks, that's good feedback! I've also been tossing around the idea of F6, if for no other reason than intrigue of the transformer. Any thoughts on Aleph vs F6?
ahem , let's talk about fun of building ...... instead of joys of simply having?
if in doubt , buy one set of mechanicals (case , PSU , all terminals) and both electronicals you're interested in
make one first , listen for a month
out with electronicals , put second one in , listen for a month ......
buy another set of mechanicals , few sets more of other electronicals ....... fun guaranteed
if in doubt , buy one set of mechanicals (case , PSU , all terminals) and both electronicals you're interested in
make one first , listen for a month
out with electronicals , put second one in , listen for a month ......
buy another set of mechanicals , few sets more of other electronicals ....... fun guaranteed
Attachments
ahem , let's talk about fun of building ...... instead of joys of simply having?
if in doubt , buy one set of mechanicals (case , PSU , all terminals) and both electronicals you're interested in
make one first , listen for a month
out with electronicals , put second one in , listen for a month ......
buy another set of mechanicals , few sets more of other electronicals ....... fun guaranteed
Also a great point. I need to remind myself that an amp can also be 'disassembled' 😀 And I do love the build, or at least have on the limited number of projects I've tackled. I suppose having the A30 around means I can always do some swapping and a/b listening.
Hi.Is it good to use FQA28N15 at the output of Babelfish J amp? Because it seems these mosfets have very good specs.They are better than IRFP150.Regards
I didn't tried
if you believe they're good (Rdson, xconductance, dissipation, SOA, capacitances ...) then use them 🙂
if you believe they're good (Rdson, xconductance, dissipation, SOA, capacitances ...) then use them 🙂
Hi.Yes it seems FQA28N15 have similar Power, half input capacitance, 1,5 times xconductance and about 1,5 time Rdson of the IRFP150N.
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