Vintage Tube & Vintage FET Microphone PCB Kit For DIY & New D7 Custom Capsule

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Studio Mollan said:
Just a question about the m49 builds. In order to build these you need to get your hands on a ac701 right? Pretty expensive for the DIY community... Any chance of a mod to use ef86 or something similar?
/
Emil

these are full original Layout but i have been in touch with 0dbfs and read stuff from Oliver at AMI that suggest using the 5840 as the second best tube outhere to replace the AC701K,  some tweak on the supply and might be some value change or omission but not more than that,

Best
Dan,
 
the more i read the more I think that the 5840 is a drop in replcement  or even th ef732 IIRC
investigation continues,  :)
dan,
 
A quote from Oliver A,

Hello Guys,

there are a bunch of tubes that will work and pass signal to call it close enough to an AC701, but there is virtually no tube that will sound the same. 
There is the AC761 made by RFT an east german copy, that looks and feels the same but the noise figures are pretty bad compared to an real one.
The EC1000 looks pretty similar and gets close to the sound, but the lifetime is pretty short and noise can be an issue.
That far I used the 5840 as general replacement, it give an in the direction feel....

Best regards,

Oliver
 
micaddict said:
the more i read the more I think that the 5840 is a drop in replcement  or even th ef732

Yup.

any toughts on wich traffo should get picked up First..

DMR.jpg


58d0281993a5d.jpg


Best,
Dan,
 
Dany, my remark was to confirm that 5840 and EF732 are the same; not that they're a direct replacement for the AC701. Perhaps I understood you wrong there. There are wiser guys than me, but for starters and from the back of my head, the 5840/EF732 is 6.3 volts (like the EF86) rather than 4 volts on the AC701. Other data I'd have to look up.
That said, I'm pretty sure that Flea has used both the AC701 and the 5840/EF732 in their M49s (with the first option being more expensive most likely).
Also, Brauner has great succes with the 5840/EF732 tube (Philips Jan). Dirk pairs 'em with  Lundahl or custom trannies, but those may be a little too "clean" for vintage sound. I guess brands like AMI and Cinemag would be the ones to look into. And who knows, Max might make you a nice one.  :)

Oh and BTW, should you get lucky with 5840/EF732 tubes (not Brauner or Flea rejects LOL) in an M49 circuit, it could be a very nice idea to do a DU67 version with that tube, making it M269-ish.
 
micaddict said:
Dany, my remark was to confirm that 5840 and EF732 are the same; not that they're a direct replacement for the AC701. Perhaps I understood you wrong there. There are wiser guys than me, but for starters and from the back of my head, the 5840/EF732 is 6.3 volts (like the EF86) rather than 4 volts on the AC701. Other data I'd have to look up.
That said, I'm pretty sure that Flea has used both the AC701 and the 5840/EF732 in their M49s (with the first option being more expensive most likely).
Also, Brauner has great succes with the 5840/EF732 tube (Philips Jan). Dirk pairs 'em with  Lundahl or custom trannies, but those may be a little too "clean" for vintage sound. I guess brands like AMI and Cinemag would be the ones to look into. And who knows, Max might make you a nice one.  :)

Oh and BTW, should you get lucky with 5840/EF732 tubes (not Brauner or Flea rejects LOL) in an M49 circuit, it could be a very nice idea to do a DU67 version with that tube, making it M269-ish.

Anyone would happen to know in details what would be the adaption for the 5840 tube for the M49 circuit as i have some pcb coming my way and they are all original circuit ,  the power supply is calculated for B+ 120V and a remote pattern operation 120. 60. 0V and the Heater should be tweakable enough for both version of tube ,

Let me know  ,

Best,
Dan,
 
micaddict said:
Can't help with the adaption. But to add to my earlier post, apart from Flea, David Bock and Oliver Archut have also used the 5840/EF732 tube for some or their M49 incarnations:

http://recordinghacks.com/microphones/Soundelux/e49

http://www.tab-funkenwerk.com/id84.html
Plus a quote from Oliver about the tranny he uses (and makes):
" for the 5840 I used the AMI BV11R (the one that was used for the C version)."

thanks Miccaddict , i spoke with Oliver this morning and he suggested the budget T49  for trannie and also the budget 5840 miniature tube , i just ordered both,
as far as i know now the C version will require the heater at 6-6.3V and the b will require a value change for proper bias but iam still working on it ,
if i can afford a ac701K one day then the tube will pop right in as well ,
Let see what happen from here , i will keep you posted,
thanks for the info
Dan,


 
Oh and BTW, should you get lucky with 5840/EF732 tubes (not Brauner or Flea rejects LOL) in an M49 circuit, it could be a very nice idea to do a DU67 version with that tube, making it M269-ish.

After this tweaking and M49 experiment I beleive the M269 version of the D-U67 will be my next project ,
;)

Dan,
 
The Store is back online ,

Happy New year All,  :)
Best,
Dan ,
 
D-M269   i was hoping finally having fun with subminis  ;)


MKBV12 D-M269
D-M269BV12.jpg


AMIT67 D-M269
58d0281993a6c.jpg


Dan.
 
Dany,


  you are utterly, erm, brilliant! 


    Are those pcb's to scale? if not, how big are they? I have an AC701k that I have been keeping as a spare for my Sela T25 . . . Maybe I will make an m269 or u367 with my u87 . . .


  m269 or u367 are just amazing, and I've used a few in me time . . . much smoother than u67.



              KIndest regards, as ever,




                  ANdyP
 
    Are those pcb's to scale? if not, how big are they? I have an AC701k that I have been keeping as a spare for my Sela T25 . . . Maybe I will make an m269 or u367 with my u87 . . .

The M49 round pcb is 60mm diameter , the M269 style is the same as U67 dimension , the M49 square version is same as fet 47 for alctron style body ,
if you need to check the dimension there is a link

https://cdn.groupbuilder.com/groupdiy/u/39511/58d0281993a76
Best,
 
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