U67 build PSU question

[Greenie]

Hi. I am working on three u67's at the moment, one from vintagemics, one from Vami and one from a gut in Sweden. Do I have to build threes different PSU's or could I just use one? What would be gainst that and what would make it possible?

 

[Khron]

Three different psu's would allow you to use all three mics at once?

Depending on how you decide to wire the multipin connectors, you may or may not be able to use the same cables, even.

And, well, since we can't have any idea if all those use the exact schematic of the original or not... the question is kinda like "how long is a piece of string?"...

 

[Moby]

Hi. I am working on three u67's at the moment, one from vintagemics, one from Vami and one from a gut in Sweden. Do I have to build threes different PSU's or could I just use one? What would be gainst that and what would make it possible?

If you use the same multipin connector and same pinning, of course, than you can use one PSU (at the time) but you should build 3 PSU's. Right? If you use non regulated, or zener regulated PSU variant as the original, you will probably have to adjust it for the corresponding microphone to achieve correct voltages because of the tube diferences. Mostly because of the heater curent tollerance.

 

[Greenie]

If you use the same multipin connector and same pinning, of course, than you can use one PSU (at the time) but you should build 3 PSU's. Right? If you use non regulated, or zener regulated PSU variant as the original, you will probably have to adjust it for the corresponding microphone to achieve correct voltages because of the tube diferences. Mostly because of the heater curent tollerance.

Thanks Moby, I am trying to grasp the microphone that goes under the name of u67, and why the DIY builds all seem to be so different. The Vami u67 is said to be without the eq, the swedish one is looking a lot like the original and the one from Vintagemicrophonepcb, is yet different again. The ywo main voltages is B+ 210VDC and 6.2VDC at the tube isn't it. or?

 

[Moby]

Thanks Moby, I am trying to grasp the microphone that goes under the name of u67, and why the DIY builds all seem to be so different. The Vami u67 is said to be without the eq, the swedish one is looking a lot like the original and the one from Vintagemicrophonepcb, is yet different again. The ywo main voltages is B+ 210VDC and 6.2VDC at the tube isn't it. or?

People often design "inspired by" projects what can be diferent from the original design. Probably because of the mechanical limitations transformer variants and capsules. I presume that's the reason of the difererences. But, generally they share the same voltages and yes +210 and -6-6.3v volts are those. Since U67 PSU is not fully regulated (original one) I mentioned the detail about possible trimming from mic to mic.