U47 Clone Distorts Easily

[o3misha]

BTW, don't forget to learn from AG what was the problem with your mic, it is very interesting,

 

[Phrazemaster]

I will hope he discovers this. Before sending it off I redid a portion of the High-Z section. Still no joy.  :-\

 

[Phrazemaster]

Just thought I'd post a few pix while waiting for repair/upgrade. As it were...

Hi Z section...

 

[Phrazemaster]

Another

 

[Phrazemaster]

I replaced the Bosche with a 1uF V-Cap OIMP.

 

[Phrazemaster]

Pic

 

[o3misha]

the contacts that are responsible for the contact to the removable head, must be soldered to the subsequent parts springy piece of wire. Otherwise, a plastic substrate may crack during the installation of the head to the body,  tightening the screws to the rails.

 

[Phrazemaster]

If I understand you right, one of the pix of the high-z was prior to soldering the blue wires. I like to have the wires formed and in-place solidly with good mechanical connection before soldering so I get a good connection. If you check the other pix the blue wires are soldered.

Unless you meant something different, in which case I didn't understand.

Thanks

 

[o3misha]

Your blue wiring connecting the female contacts with a high resistance part should be longer. Sometimes they looks like spring (in AG microphone, for example). This is to ensure that when two male contact on the head pass through the female high resistance contacts on the top panel, the plastic is not subjected to tension.

 

[Phrazemaster]

Got it! Thx! 

 

[IndietownRecording]

Hey all, just updating. I sent the mic off to Germany today...cheapest shipping? Guess...

I did try to do the test that Fred suggested prior to shipping it. Put a 1K 1V sine wave across the transformer primary. I just got weird results. Measuring XLR Pins 1-2 or 1-3 I kept getting all kinds of different readings. I'm not sure if it's because Andreas' power supply has a capacitor across ground, or if my connections weren't tight enough. But I got everything from 8V from pins 1-3 to 120mV between the pins.

So, inconclusive, and I wasn't about to start desoldering to make a proper better test. Sorry.

Will update this thread with any further news.

Thanks,

Mike

Oh man, there's no ending to this story! What happened?

 

[Phrazemaster]

Oh man, there's no ending to this story! What happened?

I sent the microphone off to Andreas Grosser in Germany. Cost a fortune in shipping.

Andreas didn't troubleshoot/fix the mic; he gutted it and rebuilt it completely. I was sorry about that because I wanted to know what was wrong with it.

He gave me a surprisingly excellent price, and he replaced the EF12 with one of his home-brew concoctions, a FET VF14 substitute so popular amongst some of the DIY'ers. He also makes a glass tube version (a small glass tube miraculously bent/stuffed into a VF14 look-alike can), but I haven't heard this one. He said the Americans liked this one better because "it's a tube" lol.

It works beautifully. But sadly I'll never know why I was having all the problems. I would love to know, since I was very meticulous in the build.

I wish I had more to report, but sometimes when you are at the end of your string in DIY you have to call in the big boys. I hated doing it, but at least the issue is no more.

Thanks for following the thread and sorry for not having a more satisfying ending.

Best,

Mike