AKG 414 B-ULS Mod ID

[Hansblooey Ribbon]

Coming apart easily enough. The PCBs are solder wicking very well.

 

[amplexus]

What a horrible thing to do to one of the last great 414 models.

Stock it out, don’t mod it. They are workhorses as stock with a very smooth top end. If you don’t like them stock, sell them (to me!) and use the cash to get something you do love!

 

[Migs 31]

I think it was a thing at one time...

Yeah I get it,

Like techs. removing transformers from perfectly working mixing desk channels in the 80's...
Mullet haircut with black sweaters and white sleeves (either Iron Maiden or Metallica) late 80's
Or even closing the side vents on MD-441's with duct tape in the 90's,
A fad... nobody can justify those things today or even their foundations...

You can find C-414 imitation bodies like these ones (see pics), get a good metal worker to open up for the HPF, Pad, Pattern switches. Paint the bodies and one side of grill (maybe use originals).
And restore these beauties electronics and sound to their former glory, they good!
Go ! Hansblooey Ribbon Go!
You cain doowit !

M

 

[Gus]

Hansblooey Ribbon
It is good to read you seem to be returning the microphones to stock.
Looks like a fairly simple job.
The tricky part might be getting the right size electros (lead to lead distance, height and OD) so you don't have bend leads.

The following are things I might do, of course you can what ever you want.
I would maybe leave the bodies alone, maybe use push in metal plugs or nuts and bolts or have someone plug weld the holes closed sand them flat and paint.
Let the microphone show it age and use them. Think of this as kind of like patina on cars.

Good luck on the restoration

Late 70's early 80' there were all kind of questionable circuit adjustments.
Change caps to what ever the latest fad was
All ceramic caps are bad seem to come out of this era
BS about electros (There is a need to understand where caps type matter)
Adding extra power supply caps and upping the bias to power amps(I fell for this on one of my Halfer 200s went from 1 to 3 caps per side.luckily I had a second stock one add really did not notice that much if any difference IMO all this did was stress the transformer and diodes more. I then removed the extra caps)
Adding small bypass caps to electros, you need to be careful this can make it worse. IIRC LT had a good app note about issues with this in one of the books. I will look for this I think I have that book.
Tracking weight and improper? loading on phono pickup up ideas
And that was just some of the home audio stuff

 

[Icantthinkofaname]

@Hansblooey Ribbon I've actually got one of those Shuayin C414s as a complete mic if you're interested. With the stock capsule it's not good but I haven't done a capsule swap.

 

[Hansblooey Ribbon]

Friends don't Let Friends...
Have one working well now. All the tantalums were near zero ohms.
The other parts were the Vishay box resistors. Some bizarre resistor values I had to use the nearest.
Not too bothered by the holes in the body.
Replaced parts:
R01 14.3K
R02 6.65K
R06 820R
R111 2.7K
R118 47R
C09 220uF/ 25V
C10 22nF
C05, 06, 08, 11, 106, 10uF/25V
C110 4n7
C113 3.3uF/ 50V
C114 1uF/ 35V

 

[Icantthinkofaname]

Friends don't Let Friends...
Have one working well now. All the tantalums were near zero ohms.
The other parts were the Vishay box resistors. Some bizarre resistor values I had to use the nearest.
Not too bothered by the holes in the body.
Replaced parts:
R01 14.3K
R02 6.65K
R06 820R
R111 2.7K
R118 47R
C09 220uF/ 25V
C10 22nF
C05, 06, 08, 11, 106, 10uF/25V
C110 4n7
C113 3.3uF/ 50V
C114 1uF/ 35V

I'd put some conductive tape on there to cover the holes. Or maybe some aluminum either welded or attached with contact cement. Maybe the capsule is well grounded enough it isn't necessary but I'd worry about contamination too.

 

[Barry Hufker]

I was thinking some nice name plate or custom logo would look great there…

 

[rock soderstrom]

Have one working well now.

Or maybe some aluminum either welded or attached with contact cement. Maybe the capsule is well grounded enough it isn't necessary but I'd worry about contamination too.

Not too bothered by the holes in the body.

I also think it's better to close the holes to make sure the mic works properly under all circumstances.

You could use a "printed" thin metal sheet to recreate the original look or make your own design.

Good work so far!

 

[Migs 31]

Friends don't Let Friends...
Have one working well now. All the tantalums were near zero ohms.
The other parts were the Vishay box resistors. Some bizarre resistor values I had to use the nearest.
Not too bothered by the holes in the body.
Replaced parts:
R01 14.3K
R02 6.65K
R06 820R
R111 2.7K
R118 47R
C09 220uF/ 25V
C10 22nF
C05, 06, 08, 11, 106, 10uF/25V
C110 4n7
C113 3.3uF/ 50V
C114 1uF/ 35V

WOW WOW WOW!

All that abuse on that poor mic ( Never follow HI-FI trends).
All those removed caps!!! That big round hole needs to be patched somehow though.
The "bizarre" resistor values, you mean the E48 or E96 values (like 14.3 KΩ ) I guess?

Keep going man restore that baby to her former glory.

M

 

[k brown]

The Hunchback of Notre Daaamn!

 

[JeffKall]

This is what happens when a high voltage HVAC tech does their FIRST attempt at mic modding … on great “workhorse” microphones that clearly didn’t deserve such catastrophic abuse !!!

I agree with everyone promoting restoration (as close as possible to original stock) … and covering the holes with an appropriate styled custom plate to match the original look and contour that protects the internals …

I applaud your efforts to restore them to their original glory …

And I believe this instance convincingly answers that burning question …

“When is modification TOO MUCH ?”

Best Regards

 

[micolas]

Aesthetically, it can be restored with patience and creativity.
The problem remains with bringing the electronic part to the original configuration and specifications. It hurts your soul when you see such abuses

 

[micolas]

Hansblooey Ribbon,
are the capsules in good condition?

 

[zonkers31]

does it work:?

 

[Hansblooey Ribbon]

Yes. The 1st one works now. Waiting on parts for the 2nd.

 

[ZHOUJUN]

I'm surprised there's such a modification.

 

[Hansblooey Ribbon]

Mics are done, they bias up and work great. Need to find a source for the 1.2 x 6mm switch screws and inner screen material.

 

[rock soderstrom]

Kudos!