MK-U47 - build thread

Am I on the right track here? Having a bit of an eye problem... Must be the age!

Blue ok!
Green ok!
Red make extra connections
Yellow rewire pins

See attached pic for help (made with some computer trickery)

marcelkroese said:

Am I on the right track here? Having a bit of an eye problem... Must be the age!

Click to expand...

THANKS!!

Banzai said:

Blue ok!
Green ok!
Red make extra connections
Yellow rewire pins

See attached pic for help (made with some computer trickery)

marcelkroese said:

Am I on the right track here? Having a bit of an eye problem... Must be the age!

Click to expand...

Click to expand...

not so sure if yellow is wrong. maybe it doesn't matter with the heater, but if you look at the schematic, i think the first picture is right.

Yeah, I went by this layout thing here.

I'm sure someone else can confirm, as the build pics have it wired like the first pic too!

andia said:

not so sure if yellow is wrong. maybe it doesn't matter with the heater, but if you look at the schematic, i think the first picture is right.

Click to expand...

Hi,

I've completed the mics so far and am only waiting for the capsules to arrive. My Question is if I can burn in the tubes without the capsule or an equivalent capacitor attached? Would that harm the microphone?

thank you all, andi

Yes, connect capsule front (green wire) to ground for the burn in.

-Max

this way for example? thanks again  :

yes!

Though debated it is generally required that you run signal through the tubes to burn them in properly.

Been thinking about building a test/burn-in jig myself. 

ioaudio said:

Hi Everybody,

now that the correct screws finally arrived, I'm completing the assembly of the new MK-U47 batch.
Shipping starts tomorrow, and I'm now open for orders. I'll go through my list, but if you inquired about a kit in the past it doesn't hurt to send me another email.
Kit/pricing and contact info: http://groupdiy.com/index.php?topic=35667.msg437839#msg437839

A quick snapshot during assembly:

Click to expand...

Dear audio,

Cold you send a quote by PM? I am very interested in get one.

In another hand: Are you compared with a REAL U-47? Do you have any discuss about in the forum or in your website(if you have one?)?

Thanks anticipated
Opacheco.

Hello!

Are there fellow diyers who have come up with a clever way of attaching and aligning a Flea capsule holder to the MK-U47 body other than cutting the plastic screw? I want to use just one spacer. If so, I am curious of what you came up with.

All the best,

Marcel

Hi Marcel,

that's why i provided a nylon screw - so it can be easily cut for the various heights!
So just cut to required length - not too short

-Max

I was aware of that, Max. Thank you. I tried and now I'm looking for a more solid solution.  Just wondering where other DIY'ers came up with.

Screw cuts easily if needed but with the largest Thiersh mount you need all 4 inserts to reach the correct vintage height for the M7 so no trimming needed. 

My first one is finished , this was a LONG wait for the M7 !

I'm not sure about the wires of my Thiersch M7 Blueline,  is this correct ?
The omni switch doesn't work, mic stays in cardioid,
and when I touch the body, I get very loud noise.
Any tips ?

the mic itself works perfect and is very quiet ! I use RCA408.

Be sure you are testing the mic INSIDE the body and head grille! Or you will get all manner of ugly noises...

hth

Mike

Yeah I know,
I took the head grille down for the photo.

Hi Kosi,

That looks great! Got my own M7 Blue Lines today. Very excited. I was also wondering about the wiring, but I think it doesn't matter either way around. The glass switch needs some tweaking to allign and get it working properly in line with the magnet on the basket's switch. The capsule will react on any contact made to the body's mic since it's attached to that. That's why you need a good shockmount to avoid this. Let us know if you come up with tips and tricks.

Best,

Marcel

8)

All is good, after 48 hours burn in, the mic is very quiet.

And I found out about my Omni problem: When I move the switch slowly from left to right, the mic switches after one centimeter to Omni.  When I move it all the way over to the right, the mic goes back to cardioid.
I tried to adjust it, but I didn't find out, how, and I don't want to reopen and unsolder the whole HI Z area.
But I can easily live with that, I will use it in cardioid most of the time anyway.

The touch sensitivity of the body is still there, it's a little bit too much for my taste, but tomorrow I make a real world test in the studio.

All in all, this was a super nice build, I had some problems with the mounting of the HI Z area and the position of the little magnetic switch, took me quite awhile to do it (nearly) right.

A BIG thank you to Max in Vienna, you are my hero
And thanks to everyone in this thread for sharing their knowledge and findings !