Even Mighty ZM uses FR - and it implies that it's great to be WeaklingsessssssFR is for ....... Weaklingsessssss
especially FC ones
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The amp looks just gorgeous 😍Wasn’t sure about the perforated aluminum…but what’s not to like about a sexy see through top? 😉
I can easily view my thermostatic display which tells me I’m running just under 53 C while pushing 1A5 when it settles into equilibrium.
Driving a load in a cooler room made quite a difference from it idling on the bench down in the furnace room at about 55.5C.
I could most likely try going for 1A7 I think.
I’m going to spend some time with it and then switch back to the amp running 1A3 and see if I think its worth the hassle to give that chassis the same treatment.
Thanks Plott…I might still do some work to create a frame for the top plate similar to what I did with my gainclone chassis (pic).
The aesthetic case work is my only real contribution…I’m a frustrated artist.
@pfarrell
Just realized I sort of documented the rebuild of my OBs in this Sonido related thread starting around post #93…
https://www.diyaudio.com/community/threads/sonido-fullrange-driver-thoughts.338918/page-5
The aesthetic case work is my only real contribution…I’m a frustrated artist.
@pfarrell
Just realized I sort of documented the rebuild of my OBs in this Sonido related thread starting around post #93…
https://www.diyaudio.com/community/threads/sonido-fullrange-driver-thoughts.338918/page-5
Attachments
That is very nice casework. Have you considered vinyl masking for spraying on front labels/graphics? We have a Cricut in the office—totally doable and precise to make a mask. It looks the same as screen printing in the end. Thanks for the link. The OSMC are seriously legit. Super WOW really—gratitude machines—but I have to build stuff—like all of us—and there's no perfect speaker right? Crossover is primary area of education (concern?) for me without some hand-holding… also looks like this might mean biamping? Endless…
Back to J2—the SS are enroute—I think I'll not put them in immediately. Perhaps go back to M2X, see if what I feel I know 😍. Then swap for R100... basically, impossible to A/B that here... Maybe make a playlist and have a session... take some notes… dunno—some of you had both versions available to A/B.
Any reason to put in posts for resistor swapping for R118 and R122? I can't imagine going back to the 150s based on the feedback up here.
Back to J2—the SS are enroute—I think I'll not put them in immediately. Perhaps go back to M2X, see if what I feel I know 😍. Then swap for R100... basically, impossible to A/B that here... Maybe make a playlist and have a session... take some notes… dunno—some of you had both versions available to A/B.
Any reason to put in posts for resistor swapping for R118 and R122? I can't imagine going back to the 150s based on the feedback up here.
I put sockets at R118, R122 and R123?
Still have them in place. Who knows I might try all Semisouth at some point.
Previous builds going all Semisouth ran out of Iq adjustment I believe and had to swap out R123?…not sure of value.
Same may apply for DC offset. I can’t remember the values or circumstances, but its here in the thread.
P.S. Thanks for the labeling ideas. I’ve been brainstorming about that stuff for a while and may want to try something with my Iron Pumpkin/Turtle build if I don’t go for a remote/display.
Still have them in place. Who knows I might try all Semisouth at some point.
Previous builds going all Semisouth ran out of Iq adjustment I believe and had to swap out R123?…not sure of value.
Same may apply for DC offset. I can’t remember the values or circumstances, but its here in the thread.
P.S. Thanks for the labeling ideas. I’ve been brainstorming about that stuff for a while and may want to try something with my Iron Pumpkin/Turtle build if I don’t go for a remote/display.
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Pics....
Like I mentioned... easy build since those chassis I built back in 2020.....for SissySIT.... ho hum.
Like I mentioned... easy build since those chassis I built back in 2020.....for SissySIT.... ho hum.
I come back here from time to time just to check how many more people have made this terrific amp....
The best versioon, at least to my ears, is the one with one semisouth dwn. With both semisouth in place, it seemss that you loose some precision and natural timbar in sound but you get more "lush" presentation.
Did I already mention that this is THE best amp from the Mighty One? (at least from the ones I heard so far)
🙂
It is my reference for SS amp for more than two years now...
With proper tube pre-amp, it is just wonderful.
OH, did I mention that I use ZM-s tube pre-amp as well?
😀
The best versioon, at least to my ears, is the one with one semisouth dwn. With both semisouth in place, it seemss that you loose some precision and natural timbar in sound but you get more "lush" presentation.
Did I already mention that this is THE best amp from the Mighty One? (at least from the ones I heard so far)
🙂
It is my reference for SS amp for more than two years now...
With proper tube pre-amp, it is just wonderful.
OH, did I mention that I use ZM-s tube pre-amp as well?
😀
ZM's tube preamp?OH, did I mention that I use ZM-s tube pre-amp as well?
😀

A little more upgraded version of this:
https://www.diyaudio.rs/choky/WOT_preamp_and_battery_charger.html
https://www.diyaudio.rs/choky/WOT_preamp_and_battery_charger.html
Well... it happened. Long listening session yesterday with a friend. The goal was just to mess about with SUTs/phono pres and vinyl...but alas after moving speakers around and playing with height (cleaned up the bass tremendously), and some different carts—I was inspired to see what's up with J2 Babel vs M2X/Norwoods I've been playing with for the last couple of years... Oh man. J2s have been in the system since the above posts—all sorts of music/movies/listening—both on purpose and ambient....
....swtiching back to M2X/Norwood.....
Here's the thing—If someone handed me either of these exceptional amps—I'd be grateful and thrilled and happy. BUT—being able to try them both an interesting thing happened. Long story short—the J2 Babel was more "alive and engaging" than M2X! I was kinda shocked that this was the impression that both of us felt. It's completely a matter of "feeling". One really can't sit there and assign some character traits like "clarity" or "bass" (J2 does have more punch in the bass department, not as massively so as I had thought pre-comparisson). This was an emotional reaction... energy... joy....
Now—it's subtle and dramatic at the same time. I'm super glad I have both amps—and wouldn't ever suggest anyone build one over the other. Perhaps there's also component synergies in play as well. Hard to say.
[ For anyone interested in that chain, it's as follows: Hana ML/Soundsmith Zephyr MIMC star -> SP10MK2 -> Salas Ultra (also FSP+SUTs—fascinating!) -> Salas DCG3 (Muses inside) -> J2 BabelHotAction monos -> OSMC ]. Haha—when I write that out it all sounds so simple... good grief.
Thanks ZM! (And NP!!!) (makes me excited to try bi-amping and play with some open baffle stuff.)
Next up Semisouth down—can things get even better??? Gonna be a couple of weeks...
....swtiching back to M2X/Norwood.....
Here's the thing—If someone handed me either of these exceptional amps—I'd be grateful and thrilled and happy. BUT—being able to try them both an interesting thing happened. Long story short—the J2 Babel was more "alive and engaging" than M2X! I was kinda shocked that this was the impression that both of us felt. It's completely a matter of "feeling". One really can't sit there and assign some character traits like "clarity" or "bass" (J2 does have more punch in the bass department, not as massively so as I had thought pre-comparisson). This was an emotional reaction... energy... joy....
Now—it's subtle and dramatic at the same time. I'm super glad I have both amps—and wouldn't ever suggest anyone build one over the other. Perhaps there's also component synergies in play as well. Hard to say.
[ For anyone interested in that chain, it's as follows: Hana ML/Soundsmith Zephyr MIMC star -> SP10MK2 -> Salas Ultra (also FSP+SUTs—fascinating!) -> Salas DCG3 (Muses inside) -> J2 BabelHotAction monos -> OSMC ]. Haha—when I write that out it all sounds so simple... good grief.
Thanks ZM! (And NP!!!) (makes me excited to try bi-amping and play with some open baffle stuff.)
Next up Semisouth down—can things get even better??? Gonna be a couple of weeks...
@pfarrell
I guess what you mean by ‘height’ is VTA, right?
Do you have a write up somewhere of the different M2X/daughterboard combinations you have tried and what your impressions were with the OSMC at the tail end?
Do you have a digital setup (streamer/dac or combination)?
I’m not surprised by your impressions though. Whenever Aleksander gets his hands on a Pass design, he sprinkles his special sauce and voila, it’s magic! Such was my impression of the Aleph J vs. Aleph J Zen.
Best,
Anand.
I guess what you mean by ‘height’ is VTA, right?
Do you have a write up somewhere of the different M2X/daughterboard combinations you have tried and what your impressions were with the OSMC at the tail end?
Do you have a digital setup (streamer/dac or combination)?
I’m not surprised by your impressions though. Whenever Aleksander gets his hands on a Pass design, he sprinkles his special sauce and voila, it’s magic! Such was my impression of the Aleph J vs. Aleph J Zen.
Best,
Anand.
@Anand
"Height" was speaker height—getting those beasts off the floor—sat them on the Xover boxes which was kinda the design I had in mind from the start when building them—made a big difference.
Re: M2X/daughter combos—my feedback is all mixed into the M2X thread.... Suffice it to say that MJ had sent me all the new stuff before release in most cases and Norwood and Cedarburg where the family favorites. All those daughter evals where into OSMC.
And in pursuit of a mostly DIY chain—I do have this DAC in the works—all boards and chips made up and ready for testing chassis and assembly—it's a pretty complex project (for me) and motivation is a tad lacking (see last sentence in paragraph ;-). I have a couple of really good commercial DACs R2R (Denafrips) and a Schitt BiFrost 2 (Anyone not familiar with the history of DAC dev related to Schitt and Mike Moffat should read Jason Stoddard's "book" at headfi—they know their stuff over there re: DACs)... Thing is‚ I'd give up vinyl right now if I found a hi-res audio source that moved me the same way vinyl does.... hasn't happened yet—AND I've blind A/B'd for people who say they wouldn't know the difference and 100% of the time they choose the record (and there aren't clicks and pops to give anything away). Really amusing...but I digress...
AJ Zen is at the in-laws house! AJ was the first amp I heard, second one I built, that at one listening session I had to fight to stay inside my body. Literally. Really cool—BUT my AJ wasn't ever quiet—and even AJ Zen (quieter than AJ) wasn't as quiet at J2 and M2X (both virtually silent with ear in cones and vol jacked, very slight edge actually to J2)—I think I have a not quiet transformer in that build AJ case (Antek)—and maybe I should dual mono it at some point (But what about VFet!!? haha, need to finish those first). J2 has put back into our listening space a good dose of that AJ thing—but with all the clarity that M2X offers. Win win really. So yes—another keeper.
My take anyway!
Oh, and Anand—thanks for the AJ link! GREAT reading—also your system page—super good.
"Height" was speaker height—getting those beasts off the floor—sat them on the Xover boxes which was kinda the design I had in mind from the start when building them—made a big difference.
Re: M2X/daughter combos—my feedback is all mixed into the M2X thread.... Suffice it to say that MJ had sent me all the new stuff before release in most cases and Norwood and Cedarburg where the family favorites. All those daughter evals where into OSMC.
And in pursuit of a mostly DIY chain—I do have this DAC in the works—all boards and chips made up and ready for testing chassis and assembly—it's a pretty complex project (for me) and motivation is a tad lacking (see last sentence in paragraph ;-). I have a couple of really good commercial DACs R2R (Denafrips) and a Schitt BiFrost 2 (Anyone not familiar with the history of DAC dev related to Schitt and Mike Moffat should read Jason Stoddard's "book" at headfi—they know their stuff over there re: DACs)... Thing is‚ I'd give up vinyl right now if I found a hi-res audio source that moved me the same way vinyl does.... hasn't happened yet—AND I've blind A/B'd for people who say they wouldn't know the difference and 100% of the time they choose the record (and there aren't clicks and pops to give anything away). Really amusing...but I digress...
AJ Zen is at the in-laws house! AJ was the first amp I heard, second one I built, that at one listening session I had to fight to stay inside my body. Literally. Really cool—BUT my AJ wasn't ever quiet—and even AJ Zen (quieter than AJ) wasn't as quiet at J2 and M2X (both virtually silent with ear in cones and vol jacked, very slight edge actually to J2)—I think I have a not quiet transformer in that build AJ case (Antek)—and maybe I should dual mono it at some point (But what about VFet!!? haha, need to finish those first). J2 has put back into our listening space a good dose of that AJ thing—but with all the clarity that M2X offers. Win win really. So yes—another keeper.
My take anyway!
Oh, and Anand—thanks for the AJ link! GREAT reading—also your system page—super good.
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Papa's
kung
is
funniest
Fu
.
ZM's
is
good
.
Drek!
kung
is
funniest
Fu
.
ZM's
is
good
.
Drek!
With SS down you will get even more details, you will think that you lost some bass (first impression), but soon you realize its just got more defined, detailed and real. Tone character will change, and you will get that "zing and clong" in mids and highs, similar to best tube amps....for me it was really obvious change to much better sound 🙂 . For comparator - it sounded much more natural, detailed and with better bass definition than Cary sli-80.
Enjoy - you build looks fantastic!
One thing to note thought - this amp really likes high efficiency and pro drivers. With tannoy kensington GR for example, it was one of the best matching ans sounding combo-s ever, but with many low sensitivity bookshelves it's just plain boring (Ls3/a for example 😀 ).
Enjoy - you build looks fantastic!
One thing to note thought - this amp really likes high efficiency and pro drivers. With tannoy kensington GR for example, it was one of the best matching ans sounding combo-s ever, but with many low sensitivity bookshelves it's just plain boring (Ls3/a for example 😀 ).
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