MK47 PCB tube mic kit - build thread

Hi

Is it normal that with 2.3k test load i can get about 105v but with mic 103v. My mic resistance is 1.8k.

the test load gets you in the ballpark voltage so you do not damage the mic. readjust the voltage with the mic after the test load adjustment.

useme2305 said:

the test load gets you in the ballpark voltage so you do not damage the mic. readjust the voltage with the mic after the test load adjustment.

Click to expand...

103v is the max what i can get with mic. Wondering why it is 103v with mic. Because it gives about 105v with 2.3k test load and mic resistance is 1.8k. So i need lower 680ohm little bit of psu. But how much if i want get 5v more?

don't you have the 5W pot in series with the resistors? if so, just get a 330ohms to replace the 680ohms resistor and lower the resistance of the pot by turning it. this will get you in the right ballpark with enough play for the pot.

useme2305 said:

don't you have the 5W pot in series with the resistors? if so, just get a 330ohms to replace the 680ohms resistor and lower the resistance of the pot by turning it. this will get you in the right ballpark with enough play for the pot.

Click to expand...

Yes i have 500ohm pot. Ok, so 330ohms.

Hey Guys,

Just after a bit of n00b advice from anyone who has used a Beesneez body to build one of these... could you please let me know how you have installed the 7 pin xlr in the mic? Are you just using the insert and a grub screw (although that side screw hole doesn't look threaded).

I have had a bit of a play around with the insert of standard 7 pin xlr, but it's escaping me how this could be installed in a sturdy/reliable way.

Any advice welcome! Thanks!

Matt

Hi Fella's,

I've got my mk47 running with a couple 408a western electrics in it, and a blueline Thiersch M7. I had crackling for a bit, so i sat it in front of speakers and broke it in for around 4 days, the mic is now dead quiet, and sounds every bit as amazing as i ever hoped it would. I can't believe how beautiful it sounds! I'm really blown away ;D

thank you Max!, i will be ordering a second soon.

T

I'm hoping this is the right place to get an answer on this.. with regards to the Zayance PSU PCB set-up.

Will I run into trouble if I run three LED's off of the LED point?

I'm using a PSU enclosure which already had three lights mounted on the front panel, so, unless there's any reason not to, I was just going to hook them all up..

I even thought about having the top LED (next to pattern selector knob) just switch on in either cardioid or omni, as there are extra poles available on the switch. 

Also, I realised that I think the polarity switch I have installed here is a 'make-before-break' type.  Is that OK, or problematic?

THANKS!!
(can't hardly wait to switch this thing on)  ~gulp~

LED board (inside)

It may not matter, but i try to keep led's and their wiring away from my input, output and polar pattern knobs, I'd also use shielded wire just in case.

on my psi, i have the led away from the audio signal stuff, and behind a shield plate and showing through the top, it's as quiet as a mouse pissing on a cottonball (i'll post an inside pic also)


good luck

inside

Oh, that's interesting..
Maybe I should simply disconnect the LED's altogether..
I did notice, so far, my mic does have a slight background hiss, where-as others here describe their build as positively silent!
(which is obviously what we'd all love to achieve)
Could the LED wiring really cause such noise/interference?

EvLoutonian said:

Oh, that's interesting..
Maybe I should simply disconnect the LED's altogether..
I did notice, so far, my mic does have a slight background hiss, where-as others here describe their build as positively silent!
(which is obviously what we'd all love to achieve)
Could the LED wiring really cause such noise/interference?

Click to expand...

The thing you have to watch for is the current draw of the LED's. You have to remember anything you add t o PSU draws current. I still haven't put any indicator light on my PSU as I didn't have one that drew very little current in stock.

My PSU has a 6.3v normal globe lamp, so I could just disconnect the LEDs I think..

Finally finished! Sounds great! Hi-res pic can be viewed on my Flickr page: http://www.flickr.com/photos/louisstudios/

For people looking for tubes, I just tried these...

http://www.nostubestore.com/2012/08/philips-miniwatt-ts62-6028-408a.html

Awesome tubes...
-marc

Yup, I've got some, too, but haven't tested them, yet. (MK47 still in the works.)

What I can tell you all is that Koray is a great guy to buy tubes from.



Henk

Thanks marc, have to try those.

When I got them, Koray had some slightly older, D-getters left, too.
Probably not much difference, but I got them anyway. 

Hi!

Do you know if this kit might fit in a t-bone sct2000 body? I know it's ok with a sct700 but I'm not sure they have exactly the same size...

What do you think?

Best,

Rémi