MK47 PCB tube mic kit - build thread

[ioaudio]

looks fine.

 

[micaddict]

Those interested in doing this (or with a twist) may also want to check replies #727 and #729 of this thread.

 

[Kathode]

Hello everyone!
Thanks for this threat. I got so much information by reading it.

I will start building this kit and psu next days and i own to telefunken 6922. Is it possible to use them, or to mod the kit?

 

[micaddict]

Welcome!

 

[ioaudio]

I will start building this kit and psu next days and i own to telefunken 6922. Is it possible to use them, or to mod the kit?

Hi again!
No the circuit needs 6028 / 408a tubes to work correctly.

 

[Kathode]

Ok. thank you!

 

[EvLoutonian]

PSU gut shot

Hi James,

Do you mind posting a nice detailed photo of just the wiring in the back of your connectors, at PSU end?
I'm trying to get my head around the wiring of the 7 pin connector, including paths across to XLR output etc.

Much appreciated!
Evan.

 

[wave]

Evan,
Here is a pic of my wiring. I etched my own board so it might look a little different than a P2P build but the wiring is still the same




If it helps you then that is my goal!

Dave

 

[EvLoutonian]

Thanks Dave - That's awesome!

I have to wire up all of this section next, and I'm just going through all the wiring info I can find in the thread to make sure I have the best overview I can figure out. 
Pictures sometimes really do tell a thousand words though, in these cases.


Much appreciated.
Evan

 

[EvLoutonian]

Here is a pic of my wiring ...
If it helps you then that is my goal!

One more question.. Do I strictly need the two 0v conductors (pins 3 & 7 indicated on your picture), or can one suffice?

Thanks again,
Ev.

 

[wave]

Evan,
IIRC, you do need both. It's been a while since I had it open tho. There was a diagram floating around the build thread that I based my wiring on and I have no noise issues.

Dave

 

[braeden]

Speaking of PSUs, I finished mine recently... I just have to wire up the output/input connectors.

I'm getting 105V with the 2.3K load resistor when the pattern switch is off, and 110V when it's on (voltage is being supplied to the relay). Is this normal? (I might be asking in the wrong thread).

By the way, for the U48 set up, the film capacitor is connected in series with the lead going to the back of the capsule correct?

Thanks,
Braeden

 

[The Frizzle]

I couldn't source a 5W 500 Ohm trim pot in Germany.
But i got this 4W 1K pot: http://www.conrad.de/ce/de/product/444820/TT-Electronics-AB-4-Watt-Drahtdrehwiderstaende-Linear-1-k-4-W-10-
So i need 5W and it only has 4W.
My Question is: Can i put a resistor in parallel to the pot so half the current flows through the resistor and i don't need 5W anymore?
I need 325 Ohm to get 105V, so i would use a 680 Ohm Resistor in parallel to the pot which then needs to have 623 Ohm.
So I'll have 680 Ohm with 623 Ohm in parallel.

 

[Majestic12]

My Question is: Can i put a resistor in parallel to the pot so half the current flows through the resistor and i don't need 5W anymore?
I need 325 Ohm to get 105V, so i would use a 680 Ohm Resistor in parallel to the pot which then needs to have 623 Ohm.
So I'll have 680 Ohm with 623 Ohm in parallel.

Sure, no problem.

 

[tonycamp]

Hey Fella's,

I've been following this thread for a looooong time, regarding capsules for the mk47, i've read about the majestic sound of the Beezneez K7, and it's on it's way. I am going to be purchasing a M7 today!(i hope), my quandary is choosing between the REDLINE/BLUELINE from Thiersch?? All my nostalgic nerves are screaming BLUE and my practical side is saying RED and save a couple $'s, I haven't heard these 2 in person (that i know of), anyone have some feedback for me? Help me please! I'll be your best friend :-\

one way, or the other, the "pay now" button will be depressed shortly

Thanx Fella's
T

 

[micaddict]

Tony, you may or may not have seen/heard this:

http://www.panphonic.com/M7/tellme.html

The corresponding graphs were posted on several fora, including ours:

http://www.groupdiy.com/index.php?topic=29254.0

This was before the BeesNeez K7 and M7 were available.

http://repforums.prosoundweb.com/index.php/topic,33278.0.html




Henk

 

[tonycamp]

Thanx addict,

The Thiersch is a no brainer in those tests to my ears, seemed the mylar capsule had more bass than the reskinned pvc? Wish there was a comparison between a straight up redline and blueline. I decided to go with the blueline. I requested an invoice, but they haven't sent it yet, probably not till tomrw, so?... still time to vacillate :

T

 

[bubbi]

Hey guys,
is mounting the 1.5K resistor like this a bad idea?

 

[baol]

Hi all you guys, I finished today to assemble my mk47 and psu well... I have 105v on the ouput but when I connect the mic there's no signsl at all, just a few pop sometime. Any idea of what to check again? thank you a million.

Andrea

 

[HellfireStudios]

Hi all you guys, I finished today to assemble my mk47 and psu well... I have 105v on the ouput but when I connect the mic there's no signsl at all, just a few pop sometime. Any idea of what to check again? thank you a million.

Andrea

There are too many places to recommend a good starting point. Pictures of your mic and circuit will help us with solving your problem (obvious wiring mistakes). As always, double check your wiring and solder joints. A lot of times it is simply a cold soldered joint. Do you have another tube to try in the mic?

-James-