Any mods to do to C414 ULS?

[Icantthinkofaname]

I (literally) just managed to score a C414 B-ULS on eBay. Are there any mods that can be done on them besides removing the transformer to make it the first TL model? A mod other than putting a brass CK12 capsule in there I mean.

 

[Khron]

... In order to achieve... what exactly?

 

[Icantthinkofaname]

... In order to achieve... what exactly?

Assuming everything works properly on it (if not I'll be sending it back), I was wondering if there's really anything that can be improved upon. I'm asking out of curiosity because everything I can think of like transformer vs transformerless or installing an older CK12 replica is a matter of opinion. I'll be leaving the capsule alone because I want to use it as an all around vocal mic

 

[Khron]

Cleaning the capsule would be an interesting first step - i'm (cynically) assuming it has never been serviced before.

Other than that, i'd argue for the "use it for a while and see if there are aspects you're not thrilled about, and THEN considering 'fixing' those issues" approach. But that's just me

 

[Icantthinkofaname]

Cleaning the capsule would be an interesting first step - i'm (cynically) assuming it has never been serviced before.

Other than that, i'd argue for the "use it for a while and see if there are aspects you're not thrilled about, and THEN considering 'fixing' those issues" approach. But that's just me

I think you're definitely right, I believe the self noise is something like 14 dBA if it's to spec, so the only thing I can think of is maaaaybe making it transformerless.

I'm also assuming it hasn't been serviced, the seller merely said "We have checked all functions. It works fine." when asked about about whether they checked all patterns, pads, and low cut filters to make sure everything is functional. Luckily I have some mics with around the same self noise as it's supposed to be, so as long as it's not noticeably noisy and everything works I'll be happy.

The only mod I can think of is all the stuff Jim Williams did, and all I know for certain was he removed the transformer from them. This one should be a stock B-ULS with a transformer since I didn't see a TL marking or a sticker from Jim Williams or another modder.

 

[shabtek]

https://groupdiy.com/threads/akg-ck12-teflon-repair-and-surprise.75161/

 

[RuudNL]

Cleaning older C414 microphone capsules can be risky.
Often the gold already falls off 'if you look at it'...
(Anyway: be very careful!)

 

[Icantthinkofaname]

https://groupdiy.com/threads/akg-ck12-teflon-repair-and-surprise.75161/

Cleaning older C414 microphone capsules can be risky.
Often the gold already falls off 'if you look at it'...
(Anyway: be very careful!)

Apparently it works fine, so I'm assuming nothing super funky is going on. I guess we'll find out when it arrives.

If the mic doesn't work, I'll just return it or file a claim through eBay or PayPal since it was described as being tested and working.

 

[12afael]

I understand that some B-uls still have the brass ring capsule. I think it is a great mic. a lot of people will tell you to stay away from more modern versions.

 

[Icantthinkofaname]

I understand that some B-uls still have the brass ring capsule. I think it is a great mic. a lot of people will tell you to stay away from more modern versions.

Pretty sure this one's a nylon ring capsule. That's preferable for me since I want to use it on male voices and I feel like with a brass capsule I'd want it tuned for only like +3 dB.

I understand that some B-uls still have the brass ring capsule. I think it is a great mic. a lot of people will tell you to stay away from more modern versions.

I've thought about getting modern ones and then replacing the capsules so that I don't have to worry about the switches breaking. But I couldn't find a cheap used C414 XLS. Pre-COVID I saw a lot of them for like $450 USD.

 

[amplexus]

This is one of the better iterations of the 414, and probably the last really “great” 414 version imo.

Ripping the transformer out of this particular mic would be a crime. The only “mod” i ever did to mine was to put replica brass ring capsules in them.

I’m all for fun and games modding- but imo this isn’t a mic that can be “improved upon” in a way that wouldn’t make it something other than what it is. If that something doesn’t do it for you, i would suggest selling it before you irreparably mod a valuable, well regarded microphone that many other engineers would enjoy and love in it’s current format.

 

[LevinGuitar]

Some fast and stupid ideas here:

If the "A" is the front membrane, could the C101 be jumpered? Not sure what voltage goes through R108.
That would be one cap less in the sound path.

Looking for the same goal, could the C1, C2 or C3 be jumpered also? Not sure if there are two caps in series there with the S2 "disconnected"

And last don't know what type of cap and value have C9, but if it's a talantum or electrolytic, an Elna Silmic or polyester cap of same capacitance surely will do better job there.

C119 off too?

Schematic here:
https://elektrotanya.com/akg-c414b_uls_sm.pdf/download.html

 

[Midnightsun]

I understand that some B-uls still have the brass ring capsule. I think it is a great mic. a lot of people will tell you to stay away from more modern versions.

Nope, no chance at all to find a brass capsule in any ULS. The only chance having the brass capsule installed are in early EB versions

 

[Icantthinkofaname]

I'm probably gonna leave it stock. I don't know the manufacture date on it, so it could be a later one. I'm sure it's either on the PCB or I can try asking AKG about the serial.

If it dies in the future, anybody know if the TLII capsule can be tuned? Cause I'm not seeing the B-ULS capsule online anymore.

 

[blakeyboy]

I ( literally) think you should just enjoy the mic, and respect it's design.
You should ( literally) leave it as it is, and if you don't love it,
you should ( literally ) sell it to someone who will.

Just having this conversation is troubling.....

 

[LevinGuitar]

An interesting review of all versions with samples

https://sonicscoop.com/curing-condenser-confusion-an-audio-history-of-the-akg-c-414-2/

 

[MagnetoSound]

No!

 

[Gus]

I (literally) just managed to score a C414 B-ULS on eBay. Are there any mods that can be done on them besides removing the transformer to make it the first TL model? A mod other than putting a brass CK12 capsule in there I mean.

Nothing wrong with the schematic
Very nice input buffer design
cascode
BJT "helper current" transistor
And a CC
it does not get much better than that
Discrete opamp stage to a transformer

I would keep it stock(fix it if broken) or sell it
OR if you do change things keep the parts to install them if you decide to sell it and the buyer wants it stock

 

[mjrippe]

The only mod I can think of is all the stuff Jim Williams did, and all I know for certain was he removed the transformer from them. This one should be a stock B-ULS with a transformer since I didn't see a TL marking or a sticker from Jim Williams or another modder.

Anything Jim Williams says, I would do the opposite.

 

[Icantthinkofaname]

The XLR connector is a bit loose. Not terribly so but there's a noticeable wiggle. What do I need to do to fix it? Tightening the Phillips head screw doesn't help.