It’s been a long and winding road, but I finally have ZM’s 2021v Iron Pre built and singing away. Jensen iron, matched Linear Systems JFET’s, set for 6dB gain, 0mV offset and silent background at idle. Totally worth the wait, I’ve been enjoying Iron Pre in my system for the past few days. It’s a wonderful addition to my stable of gear. Well done ZM! Thanks for sharing this little gem.


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I've built a few preamps here, and this is my favorite I keep coming back to. Looking to build a "fancy" version.It’s been a long and winding road, but I finally have ZM’s 2021v Iron Pre built and singing away. Jensen iron, matched Linear Systems JFET’s, set for 6dB gain, 0mV offset and silent background at idle. Totally worth the wait, I’ve been enjoying Iron Pre in my system for the past few days. It’s a wonderful addition to my stable of gear. Well done ZM! Thanks for sharing this little gem.
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Russellc
A massive thank you to ZM for the amazing work he has put into these projects. I recently completed the slow going evolution of my iron pre.
After listening to the iron pre as my main preamp for almost a year now, I was honestly wondering if the planned addition of a AVC was actually necessary. In the spring I finally was decided to pull the trigger on the turtle AVC and replace the TKD pot as planned and I am extremely happy I did, this will not be leaving my main system any time soon!
It is still in the "test" case and the new 3U case just arrived this week from HiFi2000. Once I get the face plate finished I will post some pictures with everything in its final config, all cleaned up and with the Millet LR phone that goes very very well with iron pre.
This was a really over due update as it has really exceeded my expectations and I really cannot praise this preamp enough....thanks again ZM for all the help!
After listening to the iron pre as my main preamp for almost a year now, I was honestly wondering if the planned addition of a AVC was actually necessary. In the spring I finally was decided to pull the trigger on the turtle AVC and replace the TKD pot as planned and I am extremely happy I did, this will not be leaving my main system any time soon!
It is still in the "test" case and the new 3U case just arrived this week from HiFi2000. Once I get the face plate finished I will post some pictures with everything in its final config, all cleaned up and with the Millet LR phone that goes very very well with iron pre.
This was a really over due update as it has really exceeded my expectations and I really cannot praise this preamp enough....thanks again ZM for all the help!
so, you have it .... almost Iron Pumpkin ...... but main ingredient is here
full blown IP is better in two things - better buffer (less of its own, in particular role) and neater wiring and (trivial or not) full dual mono arrangement
but I can bet that you had more fun building it as is

full blown IP is better in two things - better buffer (less of its own, in particular role) and neater wiring and (trivial or not) full dual mono arrangement
but I can bet that you had more fun building it as is

Wow! This is fantastic!this one is "fancy", big MoBo (64step relay-resistor matrix attenuator on board) and TFT+logic module and remote
have SE pcbs, need to order Bal ones
though, down low on the list
🍻
OMG I need onethis one is "fancy", big MoBo (64step relay-resistor matrix attenuator on board) and TFT+logic module and remote
have SE pcbs, need to order Bal ones
though, down low on the list

glad to see you working
to cheer you up, episode which was forbidden in Norway, too funny


Yup, very slooooowly working...


where's Iron?
also, no need for heatsinks at mosfets, small T0220 ones on both BD transistors
also, no need for heatsinks at mosfets, small T0220 ones on both BD transistors
Ok, I'll invert them
Iron's here:
https://www.diyaudio.com/community/threads/whats-wrong-with-the-kiss-boy.293169/post-7104574
Iron's here:
https://www.diyaudio.com/community/threads/whats-wrong-with-the-kiss-boy.293169/post-7104574
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