Replaced capsule in 3 pattern mic but only figure 8 is working

[157audio]

Hi Everyone, I posted this in the Arienne Audio capsule thread but it was suggested that I make a new thread so as not to derail that. I appreciate any help!

I replaced the stock capsule with an Arienne Audio Flat K47 in a turnstile audio TAC 1100 3 pattern mic, which is marketed by Adorama. I connected the front diaphragm, back diaphragm, and backplate wires to the same locations as on the stock capsule. The cardioid and omni positions have barely any sound, but the figure 8 sounds great and is remarkably improved over the stock capsule. I have 2 mics and 2 capsules, so I left one stock at first so I could compare the difference. I've searched for answers on what would make this issue occur, but have not found anything at all. I took many pictures, so I'll do my best to explain.

This is the stock capsule and wiring, from the rear of the capsule. I marked the rear capsule wire with black to make it easier to see where I connects.

The rear capsule wire connects at the "R" marking in case it's not clear.


Here are shots of the front circuit board, both sides, with the stock capsule attached

Here is the rear circuit board, both sides


Now, here are shots of the Arienne flat k47 attached to the same on the other mic, on which only figure 8 is working. The wire colors on the k47 are:Red front, white rear, black backplate.


If anyone can make sense of this, I'd very much appreciate the help. As a figure 8 only, it sounds beautiful, so I'm hoping I can get this to work. I'm sure there's some user error on my part. Either that, or from the reading I've done, a k47 capsule achieves the multiple patterns differently than than a k67 or k87. I think the stock capsule is one of those since the backplate wire is attached to a screw on the ring?

The other thing is the mount that comes with the Arienne has 2 pieces, and I've read about a "hat" on some capsules- is the small second piece that and do I need it to make the capsule do what it is supposed to do?

I have built some DIY things (that worked!) and replaced transformers in DI's, made cables, etc, so I have half a clue, but the other half is where the problem lies...

Thanks so much for any help you might be able to give.

 

[k brown]

Sorry, I can't help with the problem, but I just have to register my appreciation for the best sentence I've ever read on this forum:

"...I have half a clue, but the other half is where the problem lies..."

 

[157audio]

Sorry, I can't help with the problem, but I just have to register my appreciation for the best sentence I've ever read on this forum:

"...I have half a clue, but the other half is where the problem lies..."

Ha! Well, that’s appreciated too. A producer I used to assist called me “jack*** of all trades.” That about sums it up.

 

[micolas]

Hi Everyone, I posted this in the Arienne Audio capsule thread but it was suggested that I make a new thread so as not to derail that. I appreciate any help!

I replaced the stock capsule with an Arienne Audio Flat K47 in a turnstile audio TAC 1100 3 pattern mic, which is marketed by Adorama. I connected the front diaphragm, back diaphragm, and backplate wires to the same locations as on the stock capsule. The cardioid and omni positions have barely any sound, but the figure 8 sounds great and is remarkably improved over the stock capsule. I have 2 mics and 2 capsules, so I left one stock at first so I could compare the difference. I've searched for answers on what would make this issue occur, but have not found anything at all. I took many pictures, so I'll do my best to explain.

This is the stock capsule and wiring, from the rear of the capsule. I marked the rear capsule wire with black to make it easier to see where I connects.
View attachment 142100
The rear capsule wire connects at the "R" marking ointment case it's not clear.
View attachment 142101

Here are shots of the front circuit board, both sides, with the stock capsule attached
View attachment 142102View attachment 142105View attachment 142103View attachment 142109View attachment 142104
Here is the rear circuit board, both sides
View attachment 142108View attachment 142107

Now, here are shots of the Arienne flat k47 attached to the same on the other mic, on which only figure 8 is working. The wire colors on the k47 are:Red front, white rear, black backplate.
View attachment 142113View attachment 142110View attachment 142109View attachment 142111View attachment 142112View attachment 142114View attachment 142115

If anyone can make sense of this, I'd very much appreciate the help. As a figure 8 only, it sounds beautiful, so I'm hoping I can get this to work. I'm sure there's some user error on my part. Either that, or from the reading I've done, a k47 capsule achieves the multiple patterns differently than than a k67 or k87. I think the stock capsule is one of those since the backplate wire is attached to a screw on the ring?

The other thing is the mount that comes with the Arienne has 2 pieces, and I've read about a "hat" on some capsules- is the small second piece that and do I need it to make the capsule do what it is supposed to do?

I have built some DIY things (that worked!) and replaced transformers in DI's, made cables, etc, so I have half a clue, but the other half is where the problem lies...

Thanks so much for any help you might be able to give.

Hi, @157audio !
So this is the microphone:

https://www.adorama.com/tac1100.html#main-product-tabs

If you are convinced that you have connected the Arienne K47f capsule correctly, then let's check a few things:
*Check if you have continuity between the backplate of the K47f and the point on the microphone PCB, with the microphone not powered.
*In both microphones, original and modified, check the correct operation of the polar pattern switch. In both microphones, without feeding them with the Phantom, with a DMM set to the Ohms range, check the continuity, the good operation of the contacts in all similar positions: cardio, 8, omni.
The other switches, Lo-Cut and Pad should be in the Off position.
*If you have a multitester/capacitor that can measure tens of pF (let's say a 100pF range), then measure and compare the new Arienne K47f capsule with the stock capsule removed from the modified mic, maybe you didn't connect the k47f backplate properly.
If everything is in order, other checks will follow, for example related to the polarization voltages of the capsule.

 

[157audio]

Thank you for those ideas. I’m out now but I’ll check those things when I return home. I know that before I changed the capsule that the pattern switch was working. But, it’s entirely possible I damaged something while I was doing the change.

Edit: as I’m riding in the car (not driving!), I looked at my pictures and on the modded mic switches, it looks like my soldering is sloppy and connected the 2 terminals by letter A (the switch board with the 1 written on it). When I look at the unmodded board, that is not the case. I would assume that would cause a switch issue if they are not supposed to be connected on that side of the switch, unlike the side with the blue wire, where the two terminals are connected. Am I onto something there? That’s the first thing I’ll check when I get home!

 

[micolas]

The stock capsule in this mic looks very familiar to me. It is similar to the one used in the new Behringer B2-pro version with smd parts, so 797 CY002, which is an excellent capsule. I used it in a U87 clone, which sounds great. If confirmed, if I were you I would keep one of the mics with this capsule and modify it for a sound from the 87 family. I'm starting to see this cheap mic from a different perspective

 

[soliloqueen]

check whether the figure 8 is done with front diaphragm at 0 or not

 

[157audio]

check whether the figure 8 is done with front diaphragm at 0 or not

This may sound like a silly question, but would I trace the circuit from where the front connects to see if it winds up at ground? I guess that’s how I would tell, as the mic didn’t include any documentation that would indicate that, or if it did I don’t understand it as such.

I’d I find that it does use front diaphragm at ground, is that how it should be or how it should not be for this to work as intended?

 

[abbey road d enfer]

Are you sure the white and blue wires are connected where they should?

To me, it seems it seems like the blue and whire wires are crossed.

 

[157audio]

The blue wire is where it was attached originally. The white wire is the rear capsule, the black wire is the backplate (the wire attached to the frame of the capsule), and the red wire is the front capsule.

I am not certain that things are connected correctly, but these are the same positions as the original wiring. It’s entirely possible I’m confused but looking at the pictures it seems things are connected where they were. I’m going to go downstairs in a little bit to take things apart again and double check. Thanks for your advice, I’ll report back.

 

[abbey road d enfer]

Well, it does not seem to match the markings on the PCB.

 

[soliloqueen]

Well, it does not seem to match the markings on the PCB.

F is going to front, P is going to backplate and R on the switch board is going to rear in both pictures from my perspective, though the rewire is a little messier. I don't think he has the contacts wrong, this makes sense to me. It must be something else

 

[abbey road d enfer]

F is going to front, P is going to backplate and R on the switch board is going to rear in both pictures from my perspective, though the rewire is a little messier. I don't think he has the contacts wrong, this makes sense to me. It must be something else

I agree but the white wire goes to P.
OP should try to rewire this white wire to the RH part of the picture.

 

[soliloqueen]

I agree but the white wire goes to P.
OP should try to rewire this white wire to the RH part of the picture.

That's R. we've got blue going to the right side of the top of the board and rear diaphragm marked with black Sharpie going to the center. In his modded board it's the other side of the board and we've got blue on the left and rear diaphragm which is white going to the center still, so it doesn't seem like the hookups are wrong. It might just be he's got a bridge somewhere. Either that or I'm just getting confused from the board constantly changing orientation

 

[abbey road d enfer]

That's R. we've got blue going to the right side of the top of the board and rear diaphragm marked with black Sharpie going to the center. In his modded board it's the other side of the board and we've got blue on the left and rear diaphragm which is white going to the center still, so it doesn't seem like the hookups are wrong. It might just be he's got a bridge somewhere. Either that or I'm just getting confused from the board constantly changing orientation

Since we don't know how the connections between boards are organized, I would take no risk and connect all wires to the main PCB.

 

[Khron]

There seems to only be one single capsule bias voltage coming out of the oscillator board, so I'm gonna guess it's closer to 120V or so, as in the CAD GXL3000 schematic (top-left).

http://recordinghacks.com/images/mic_extras/cad/gxl3000-schematic.png

That should then get divided in half on the audio board (i see a whole bunch of 20meg resistors there, the "206" marked ones) probably, and the mid-point would end up... somewhere - bear with me, I'm trying to figure this out as i go.

I believe it would make most sense that the front diaphragm was grounded, the mid-bias (60v) ended up on the backplate (point "P"), while the full bias (120v) would end up at point "A".

On the switch board, the rear diaphragm "R" is floating for cardioid, gets connected to the DC-grounded (via 1G resistor) "F" for omni, or to the 120v "A" for fig-8.

I stand to be corrected though, this is just what i managed to scrape together from clumsily swapping through a couple of those board photos on my phone...

PS. Also, some of those socket headers seem pretty well melted - are you 100% certain those are still mating properly with all pins???

 

[157audio]

There seems to only be one single capsule bias voltage coming out of the oscillator board, so I'm gonna guess it's closer to 120V or so, as in the CAD GXL3000 schematic (top-left).

http://recordinghacks.com/images/mic_extras/cad/gxl3000-schematic.png

That should then get divided in half on the audio board (i see a whole bunch of 20meg resistors there, the "206" marked ones) probably, and the mid-point would end up... somewhere - bear with me, I'm trying to figure this out as i go.

I believe it would make most sense that the front diaphragm was grounded, the mid-bias (60v) ended up on the backplate (point "P"), while the full bias (120v) would end up at point "A".

On the switch board, the rear diaphragm "R" is floating for cardioid, gets connected to the DC-grounded (via 1G resistor) "F" for omni, or to the 120v "A" for fig-8.

I stand to be corrected though, this is just what i managed to scrape together from clumsily swapping through a couple of those board photos on my phone...

PS. Also, some of those socket headers seem pretty well melted - are you 100% certain those are still mating properly with all pins???

Wow.

And I did realize that I hit those sockets with my soldering iron- my hands aren’t the most steady sometimes due to arthritis. Im wondering if I should try to put a capsule in the second one now that I have a better idea of how to get this apart and such. With the mics only being $70, chalking one up to research and learning isn’t so bad. I usually learn best by making mistakes and figuring my way back out (with help).

I didn’t get to touch the mics last night again after getting home from a family gathering for Christmas, so I appreciate all of the thoughts that were posted overnight. I’m going to read through things carefully and make a list. But, I do have the feeling that trying mic 2 while being more careful may be a good way to go. If I don’t accidentally melt a piece and things like that, and it winds up at the same point, then I can eliminate that as a factor.

 

[Voyager10]

Is the 'figure-8' pattern working entirely as it should - so you get sound picked up at both front and rear and a proper null at 90 degrees?

 

[157audio]

Ok, I’m happy and sad to report that the flat k47 in the other mic works correctly. I bet that the melted socket or some of the sloppy soldering is messing the 1st mic up. So, I’ll try wiring those pins to the circuit board directly and getting the socket out of there. I’m also going to check the joints on the extensions I soldered to the capsule wires on the first one, because I didn’t extend the wires on the second.

Worst case scenario is that I buy another mic and do it again. $70 for a learning experience isn’t so bad.

 

[Khron]

getting the socket out of there

... Or you can replace the socket, assuming you can get your hands affordably on some suitable-height piece.