D-M269B Build Thread.

[poctop]

I don't think there is a U67c, just a U67, unless you've altered the circuit in the DU-67. Is your U67 "b" or "c"?

correct this was just a way of describing that the heateer voltgae is indeed isolated from the kathode in a U67,  the circuit do not have any alteration just the old U67 .

Sorry for the confusion ,
Dan,

Well this is a tiny bit over my head, because I'm basically a n00b, so I don't know if that means self bias or not. Apologies.

I guess what I'm saying though is that your U67 and M269b should sound almost the same.  Unless 1) the capsules in both mics that you're comparing are not consistent with each other, or 2) the 5840 results in a darker sound than the AC701k

I wil be building  a 269C also , when this is done i will have to do another M49C  and then i will try to shoot out the whole collection,

Stay tuned,
Dan,

 

[ShellShock]

A .WAV posted shootout between all these DIY mics would be epic indeed. Then I can pick and choose which one I like best..which will likely be all of them...
Tonight I will be making two of them on the hood of a Humvee in Africa, pictures will be posted!

 

[poctop]

A .WAV posted shootout between all these DIY mics would be epic indeed. Then I can pick and choose which one I like best..which will likely be all of them...
Tonight I will be making two of them on the hood of a Humvee in Africa, pictures will be posted!

i'd like to get a picture of gazelle too if not too much asked,  ,
Best,
D

 

[poctop]

important Information For All M49 and 269c builder

the psu pinout  connection shows that pin 3 is the cable shield lift channel with the jumper that should be by default installed on the psu , unless a specific cableshield scheme is used  and that pin 7 is the Audio Ground ,

on the M49 Mic pcb as per the original numbering the pin 7 is actually the shield from chassis and the pin 3 is the audio ground ,
since the 2 points are linked on the pcb they are basically the same but special attention must be taken to actually take into account for this properly grounding the mic and cableshield as the number are reversed on the mic end ,

take special attention to ground loop while grounding the shield of the mic cable ,


the same PSU can be used for the M269C build but note that the difference is that pin 3 is the calibration input on the mic pcb not the shield ,
there is a pad on the 269 pcb labeled Cal on the mic pcb. Always have the original schematic of the mic when building as all the numbering on the mic pcb always follow the original numbering on the schematic as opposed to the psu that will always stay te same for both mics 49bc-269c ,
the remote pattern on the M269c is like the original as well that is you have to switch on the mic pattern and then on the psu to get the poper pattern , ( see schematic)  the use of a linear pot can be used in both configuration for the pattern ,

Best,
Dan,
 

 

[poctop]

A .WAV posted shootout between all these DIY mics would be epic indeed. Then I can pick and choose which one I like best..which will likely be all of them...
Tonight I will be making two of them on the hood of a Humvee in Africa, pictures will be posted!

i'd like to get a picture of gazelle too if not too much asked,  ,
Best,
D

Still waiting for this picture ,  ,
Best,
dAn,