Topic: AKG B.i.G./CK91 (NEW MOD) detachable Blueline series caps

[leehookem]

Not trying to compete as I'm not doing a ck91 mod, but my ck6x coupling will probably be $99 including the (mono) PFA.  I am not doing the metalwork though, I will hire that out, which will run in the $10-$15 range per unit, depending on volume.  I also hire out powdercoating, which costs me about $0.50/unit.

Count me in!  I've got a pair of ck63 caps looking for a connection...

  Richard

Me too!

[igene]

I'm curious, are you guys interested in my mod CK91/93 or Jon's CK6X

[leehookem]

I'm interested in both actually.

[illconditioned]

I'm curious, are you guys interested in my mod CK91/93 or Jon's CK6X

I'm just waiting for the CK6X.  I've already got a set of modded ck93...

  Richard

[igene]

Has anyone listened to the sample clip ?

[EarlyMorningRain]

^ just did and sounds nice! I know it's mono (single cap), but maybe try it out in the field?

[igene]

^ just did and sounds nice! I know it's mono (single cap), but maybe try it out in the field?

I'm waiting on supplies...
I'm out of miniXLR connectors, and don't have any cables made up.
I just have my 1 shorty 12" one for testing.

As soon as I get the delivery, I'll make up cables and roll a show ASAP.
I just posted the clip to show High db is not an issue, the mic sounds real nice, and that 9v will power it no problem !

that's all I can do for now.
money is tight, so 1 step at a time.

[ArchivalAudio]

back a bit I saw a 9v to 16v range for the ck91
does this mean 16v is the max?  if I set my Littlebox to 20v phantom that's too much?
or would I just run the Naiant PFA with these.... I understand that would work fine.
 thanx for the awesome work Gene  I would totally find a machine shop to make you say 100 pieces or get quotes and price-breaks.
thanx
--Ian

[igene]

I actually don't know the full answer to that question.
With the preamp body, the mic works great from 9 - 48v
The cap itself ? I would say 9 - 16/18v is good...anything more I'm unsure of.
(20v may still be OK / without knowing more)
It may work fine up to 48v., but I need to research that...

If anyone knows, please help.

[igene]

right now I have the cap connection wired >

Pin 1: Shield
Pin 2: Battery (+)
Pin 3: Audio

no extra resisters inline or anything.
It works fine w/ a CA-9100 providing 9v.
Are you saying that I should only run these at that voltage because it's efficient enough @ that voltage ?

Also, I'm only going to make these 3 wire / balanced.
What would be different, or needed to run it with a tiny or little box ?

[illconditioned]

To iGene and others: I don't have time to answer questions by PM.  Please post the questions here and (hopefully) someone will answer them.  Or I will answer them once, and not multiple times.  I am trying to help out by posting what I have, but I have to limit my time here.  I say that while obsessively following the posts, but I'm still trying, lol.

  Richard

[igene]

Can someone confirm this is correct.
Thank you.

standard miniXLR wiring is :
Pin 1: Shield
Pin 2: Battery (+)
Pin 3: Audio


PCB wiring :



the Blueline lav mic I used for wiring ref. :


How I have my CK91 PCB wired :




Thank you.

Sorry to ALL for any OD in the PM department.

[illconditioned]

I'm not sure about the pins you've labeled on the CK9x circuit board.  This is a loooong time ago for me.

However, I *think* miniXLR should be wired differently.  The way I've seen AT853 and family, it is:
pin1: shield
pin2: audio
pin3: battery +

If you look inside the AT853 power modules they usually have a load resistor (5.1k or something?) between audio and ground, and then take the signal off pin 2.  The voltage is something like 5-9V.

If you have a choice, I would follow the AT853 convention for any three wire mic.

However, it is probably simpler to put a load resistor between pin 2 and 1 *inside* the ck9x capsule, and then just put a two wire connection on the output and use a standard "two wire" battery box.  The trick is the value of this load resistor.  I'm guessing something like 10-15k might be more appropriate.  Notice that the recommended value in the circuit I posted (from AKG directly) is 13.3k.  So, you're doing something like the standard 4.7k mod, except using a 13.3k resistor in this case.

  Richard

[igene]

I look at the schematic, and it shows 3 resistors present in the circuit already. (R1, R2, R3)
Aren't they performing the exact the function you are describing ?


also, in the picture (3rd image) of the lav connector/ PCB board: is RED (+) and Blue (-) ?
I've been over this a dozen times and I'm 99.9% sure that I've wired this correctly,
I just want to be 200% sure.
----------------------------------------------------------------------
add:
OK, I got it. 200%, I'm right!
pic 3 and 4 are the key /then cross ref. to the 1st schematic.
Both are the underside of the PCB.
If you start at the ground and go right(up)...the next contact point is BLUE or (-) in both instances.
That corresponds to the 1st schematic as well.

I'm sorry I second guess myself, but I prefer the piece of mind.
whew !

[it-goes-to-eleven]

So, to digress just a bit.  How would that circuit look if driving a 60v capsule that has only 1 connection pin + ground?