For those interested in using the "fancy little seat", I've posted the 3D print files in the "Parts" forum. Just another option for anyone using the "Lip Up" orientation of the perforated base plate that's interested in trying it out. I made an update to include a second slot to allow the transformer to be mounted in a 3U size chassis, keeping the transformer as close to the chassis front plate as possible.
https://www.diyaudio.com/community/...on-over-chassis-plate-lip-up-3d-print.410708/
https://www.diyaudio.com/community/...on-over-chassis-plate-lip-up-3d-print.410708/
@Vunce
Best to wait his reply, but as far as I remember his reaction - difference wasn't night and day
in fact, from my previous endeavors with J271 in place of 2SJ74, that old one was not slouch at all ....... and this one ( presented) is made with more mileage than old one
that's why you can read on schematic in first post:
"JFets arrangement:
case 1: J1,J2 - 2SJ74BL or V/LSJ74B or C
case 2: J1,J2,J3,J4 - 2SJ74/LSJ74 any suffix or
J270/271
case 3: J1',J2',J3',J4' - mmbfj270/271
all matched"
so, pair of 2SJ74BL as regular option
quad of any suffix 2SJ74 for those filthy rich Greedy Boyz
quad or J270/271 - double, to compensate lesser xconductance of cheapo ones; sorta diminishing stock parts
quad of mmbfj270/271, again - double, same reasons, regularly available part
Best to wait his reply, but as far as I remember his reaction - difference wasn't night and day
in fact, from my previous endeavors with J271 in place of 2SJ74, that old one was not slouch at all ....... and this one ( presented) is made with more mileage than old one
that's why you can read on schematic in first post:
"JFets arrangement:
case 1: J1,J2 - 2SJ74BL or V/LSJ74B or C
case 2: J1,J2,J3,J4 - 2SJ74/LSJ74 any suffix or
J270/271
case 3: J1',J2',J3',J4' - mmbfj270/271
all matched"
so, pair of 2SJ74BL as regular option
quad of any suffix 2SJ74 for those filthy rich Greedy Boyz
quad or J270/271 - double, to compensate lesser xconductance of cheapo ones; sorta diminishing stock parts
quad of mmbfj270/271, again - double, same reasons, regularly available part
Hi All -
AJ a la ZM ... or AJzm. No one has missed anything. They will be in the store... soon... ish.
Let's not get ahead of ourselves. ZM, no more teasing the Greedy Boyz...
All will be posted in good time and in one place. 
It's always fun when people may enjoy a new project...
The long story...
--------
Those that have built or seen the schematics for ZMs iteration of the Aleph J know it well. See @poseidonsvoice post above to know what boards we're talking about. From a novice (my) perspective it was / is wonderful because it didn't require matched output devices and it was (to me) a bit simpler to build and set up than the existing Aleph J boards. Most importantly, as we all know... EVERYONE should build an Aleph. So, how could we make building an Aleph even more approachable...?
ZM to the rescue... again.
It was painfully clear to me while I was working on the Iron Pre that the world's supply of K170 and J74 devices is fixed. We're insanely lucky to be able to get them, but they won't last forever; and yes, Virginia, there are alternatives. Also... we all know that through-hole is on the decline. So, rather than put a design out that was only tested with the famous J74's ... I asked ZM about other alternatives. In his kindness and infinite wisdom, he created at least 4 board designs for alternatives. I ordered a bunch and was lucky enough to learn how to test them under his guidance to make sure they performed to his expectations even in the hands of the average dodo (me).
I tested all but the SMD versions very thoroughly with a variety of components in various configurations. We even did some surgery on a few. After I asked a typical dodo question, we agreed to make one set of "flexible" boards vs. having different boards for different JFETs . He's devilish and already knew it would work ...
ZM is a very patient teacher... I may have had a few moments of 
Get to the point you cry!!!...
Fine...
So... the "store" boards will be suitable for (as ZM mentioned above)...
The kits will include all the parts to stuff the PCBs (with matched quads of J270s).
Soon... ish... kits to build a couple of these boards will be in the store.
I think it sounds just swell in all configurations. Again, this is DIY... it's fun... and YMMV. I'll post some giggly wigglies for the final iteration when I get them done.
Also @birdbox is too modest... he was a huuuuuge help.
Papa, ZM, and 6L6...
AJ a la ZM ... or AJzm. No one has missed anything. They will be in the store... soon... ish.
Let's not get ahead of ourselves. ZM, no more teasing the Greedy Boyz...
All will be posted in good time and in one place. It's always fun when people may enjoy a new project...
The long story...
--------
Those that have built or seen the schematics for ZMs iteration of the Aleph J know it well. See @poseidonsvoice post above to know what boards we're talking about. From a novice (my) perspective it was / is wonderful because it didn't require matched output devices and it was (to me) a bit simpler to build and set up than the existing Aleph J boards. Most importantly, as we all know... EVERYONE should build an Aleph. So, how could we make building an Aleph even more approachable...?
ZM to the rescue... again.
It was painfully clear to me while I was working on the Iron Pre that the world's supply of K170 and J74 devices is fixed. We're insanely lucky to be able to get them, but they won't last forever; and yes, Virginia, there are alternatives. Also... we all know that through-hole is on the decline. So, rather than put a design out that was only tested with the famous J74's ... I asked ZM about other alternatives. In his kindness and infinite wisdom, he created at least 4 board designs for alternatives. I ordered a bunch and was lucky enough to learn how to test them under his guidance to make sure they performed to his expectations even in the hands of the average dodo (me).
I tested all but the SMD versions very thoroughly with a variety of components in various configurations. We even did some surgery on a few. After I asked a typical dodo question, we agreed to make one set of "flexible" boards vs. having different boards for different JFETs . He's devilish and already knew it would work ...
ZM is a very patient teacher... I may have had a few moments of Get to the point you cry!!!...
Fine...
So... the "store" boards will be suitable for (as ZM mentioned above)...
- A matched pair of J74
- A matched quad of J74 for those with some around or $$$
- A matched quad of J270/J271
- A matched quad of mmbfj270/271. Choose your own adventure. For advanced DIYers willing to go it alone.
The kits will include all the parts to stuff the PCBs (with matched quads of J270s).
Soon... ish... kits to build a couple of these boards will be in the store.
I think it sounds just swell in all configurations. Again, this is DIY... it's fun... and YMMV. I'll post some giggly wigglies for the final iteration when I get them done.
Also @birdbox is too modest... he was a huuuuuge help.
Papa, ZM, and 6L6...
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Aahhh, shucks. Thank you Patrick! I'm blushing and my head is starting to swell from your endorsement. And with that…
I’ll offer up my amazing services that I’m now advertising as “Birdbox’s Baffoonery Board Build B’niss”
Do you have a pre-production prototype project that needs someone to find where noob dodos can go astray? I have just the right amount of overconfidence combined with lack of experience and inadequate knowledge to find nearly all the places someone can screw up your awesome build.
I may not find all the pitfalls a diy-audiophile caveman can fall into, but I’ll find a heck of a lot. Not only are my services likely second to none, I’ll do it for free. Heck, I’ll pay you so that I can screw up your builds and help find where the guide guard rails are needed. PM me today to find out my availability. Don’t wait, these services won’t last long. I may be dumb now, but I’m getting smarter with each and every build.
{These services are not authorized or endorsed by ItsAllInMyHead, or any other diyaudio member. All of the above are real world experience subject to needing “context” for full understanding of the situation. “Birdbox’s Baffoonery Board Build B’niss” is not a real business and just a humorous name to highlight services offered. Your results and mileage of these services may vary. Reach out via Private Message (PM) at your own risk.}
I’ll offer up my amazing services that I’m now advertising as “Birdbox’s Baffoonery Board Build B’niss”
Do you have a pre-production prototype project that needs someone to find where noob dodos can go astray? I have just the right amount of overconfidence combined with lack of experience and inadequate knowledge to find nearly all the places someone can screw up your awesome build.
- Do you need someone who will disregard the directions to not open the parts bags until told to do so, and instead dump them all out in a mixed pile? Been there, done that, can do.
- How about a self proclaimed "audio enthusiast" who thinks 100uF motor run cap has more energy storage than 18kuF Aluminum Electrolytic. I’m the dunce that made that mistake.
- Need to see if someone will solder the MOSFET to the board before tightening the board to the heat sinks, so it’s outta wack and leaves the board all bent outta shape. I’ve pulled that one off.
- How about the one where I reach out to ask you why it won’t power on, then realize I didn’t put a fuse in the power entry module. That’s a hum dinger that I’ve already demonstrated is repeatable.
- Want someone who'll skip the step in the instructions to install a jumper between two pads and struggles for 3 hours banging his head against the table wondering why it won't play music before reaching out for help. I’ve established I’m fully capable of this.
- I’ll screw up offset thinking it’s measured in “Amps” and bias is measured in “Volts”, just be sure your fully aware that I know very little. I call this “the stupefying sneak attack”.
- Once you've straightened me out, I’ll still miss the bias target, dialing it up to 1.7A, when the instructions clearly state 1.4A max. I’ll even skip over thermistor swap guidance and just let er’ rip as is. It’s a given.
- Do you need someone to struggle for 3 days trying to find what’s causing a loud transformer to hum with your ever patient assistance, still resulting in zero progress, only to find out that shutting off the recessed dimmable LED lights in the home completely removed it. This happened, and lessons were learned.
I may not find all the pitfalls a diy-audiophile caveman can fall into, but I’ll find a heck of a lot. Not only are my services likely second to none, I’ll do it for free. Heck, I’ll pay you so that I can screw up your builds and help find where the guide guard rails are needed. PM me today to find out my availability. Don’t wait, these services won’t last long. I may be dumb now, but I’m getting smarter with each and every build.
{These services are not authorized or endorsed by ItsAllInMyHead, or any other diyaudio member. All of the above are real world experience subject to needing “context” for full understanding of the situation. “Birdbox’s Baffoonery Board Build B’niss” is not a real business and just a humorous name to highlight services offered. Your results and mileage of these services may vary. Reach out via Private Message (PM) at your own risk.}
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I know ZM, I had to throw at least one funny sarcastic statement in there somewhere.
I wasn't disagreeing, I was showing my gladness
@TungstenAudio I can not find this ITXQ75N20P in a google search. Are you sure that this is the right mosfet name? What tweaks did you made to use this mosfet?
@ItsAllInMyHead when will be this kit available in diyaudiostore? I already have missed 3-4 kits sales from diyaudiostore and I do not wanna miss also this one.
@ItsAllInMyHead when will be this kit available in diyaudiostore? I already have missed 3-4 kits sales from diyaudiostore and I do not wanna miss also this one.
^ I can't imagine where I got the idea to get these and why they're on my bench in the queue... for... sometime...
@Toys4Boys - Hope the build is going well!