Topic: AKG CK91 caps

[lsd2525]

OK, this ought to be good. Couldn't decide to post here, or in the battery box or cable forum.

Bought a pair of CK91 caps, cables and batter box in the yard sale. Have a couple of questions:

Came with a (I guess) homebrew 9v battery box. From what I've read, these caps need 9-18v. If that's the case, would stepping up to 18v power get me anything? Better sound? Higher SPL?

And would powering them with something like a tinybox and using phantom power adaptors give me better sound than just running a battery box?

Also, would having the 300 bodies do anything other than acting as a pp adaptor and giving me some bass roll off options?

I've seen several posts about AKG adaptors that let you run caps on different bodies that what they were designed for. Anyone know of an adaptor for the blue line caps that would allow me to run a different body than the 300?

Thanks in advance, Dan

[lsd2525]

One other thing I meant to ask - the "side slash" openings on the sides of the caps - do these need to be open to function properly? They came with a PVC pipe DIN mount......if the caps are inserted, the openings on the sides are covered, or at least somewhat obstructed. Do these need to be in open air?

[willndmb]

I don't think the volts would really change the sound but i could be wrong
i would recommend having the slits open as much as possible
the 9x caps can not be run with other bodies

[acidjack]

OK, this ought to be good. Couldn't decide to post here, or in the battery box or cable forum.

Bought a pair of CK91 caps, cables and batter box in the yard sale. Have a couple of questions:

Came with a (I guess) homebrew 9v battery box. From what I've read, these caps need 9-18v. If that's the case, would stepping up to 18v power get me anything? Better sound? Higher SPL?

And would powering them with something like a tinybox and using phantom power adaptors give me better sound than just running a battery box?

Also, would having the 300 bodies do anything other than acting as a pp adaptor and giving me some bass roll off options?

I've seen several posts about AKG adaptors that let you run caps on different bodies that what they were designed for. Anyone know of an adaptor for the blue line caps that would allow me to run a different body than the 300?

Thanks in advance, Dan

I think these may well be a set I owned once. I liked the sound of them a lot.

No, nothing will be gained from increasing the power to the mics. If they're OK with 9, then 18 won't do anything.

The advantages or disadvantages of bodies come in a few flavors. Some "active" solutions aren't actually providing the correct rated voltage to the caps, though they work fine. You can find pages of arguments, particularly among Schoeps guys, about this. In the case of your AKGs, the SE300 body is rated 9V-52V, so that's not an issue, I wouldn't think.

The main advantage of the body would be having something more stable than the homemade wiring connecting the cap, but of course, you'd lose the enhanced portability. Having bodies would also make it easier to run different preamps with the mics rather than just that battery box or another 9V preamp. However, I'm not entirely sure if once you've wired the CK91s for this active setup if you even CAN stick them on bodies without destroying the custom wiring - I would assume not, but I didn't design the setup.

Don't cover the side vents, at all.

[lsd2525]

Thanks. Good to know about the side vents (I guess that's the technical term lol). That's what I'm afraid of. Going to make it a little hard mounting for open stand recording and leaving them open. OK, if all it needs is 9 volts, then 9 volts from a battery box vs 9 volts from an expensive preamp won't make any difference in the sound, right? Or would it?

Just realized that was a stupid question. I'm sure different preamps color the music differently

[lsd2525]

What's the best way to check the output of the box? The mic connectors are 3 pin mini xlr's. Put the multimeter to it, couldn't get a reading. Should have voltage across a couple of the pin's, right?

[vanark]

Preamps can add gain as well.  A battery box is just power to the mics.

[brn2rn]

No problem to build a 9v battery box and solder the cable directly into the capsule and into a mini-xlr.
They will take very high spl and will not need further amplification, just run straight into recorder.
Very stealthy, very efficient, very good sounding.

[lsd2525]

Just confirmed the battery box outputting 9.05v. Guess I should be good to go. Feel a lot better now that I actually saw it on the multimeter. Now I'm thinking I can run the same box with my AT853s......been using a pair of AT8531 power modules thus far. I would think that the 3 pin mini xlr terminations would probably be the same for both sets of mics.......probably?

[sinethomas]

I have been using the CK93 for a while now but have not used a ck91 cap. When i find some time i will try to post up some clips. I dont know how the sound compares to other mics but it pretty much blows my old ME66 away even though they are really 2 different mics but thats the only thing i can compare it to. I have success with it on cam and boomed indoors and out. outdoors i was using the supplied foam screen covered with a FatCat and at a pretty close range.. Still picked up some wind so i plan on getting a BBG in the near future.The mic is also way less prone to handling noise than the ME66. I have been using the k-tek kssm or whatvere the small shockmount is.

[EarlyMorningRain]

OK, this ought to be good. Couldn't decide to post here, or in the battery box or cable forum.

Bought a pair of CK91 caps, cables and batter box in the yard sale. Have a couple of questions:

Came with a (I guess) homebrew 9v battery box. From what I've read, these caps need 9-18v. If that's the case, would stepping up to 18v power get me anything? Better sound? Higher SPL?

And would powering them with something like a tinybox and using phantom power adaptors give me better sound than just running a battery box?

Also, would having the 300 bodies do anything other than acting as a pp adaptor and giving me some bass roll off options?

I've seen several posts about AKG adaptors that let you run caps on different bodies that what they were designed for. Anyone know of an adaptor for the blue line caps that would allow me to run a different body than the 300?

Thanks in advance, Dan

I own some ck91 actives, so I'll chime in and hopefully fill on some blanks that others have not answered yet.

A fellow member here did the active mod on my mics and also made a 9v battery box to go along with it.

So that was my setup initially.

Ultimately I had Chris Church make a 9100 preamp for me to run with these capsules. I had to send him my mics and existing battery box but he was able to configure a 9100 preamp to work with the ck91 capsules. If you want to consider a tinybox to use with these, you will have to check with Jon/Naint first before you go buying something first.

But NO you cannot use phantom power when using just the capsules! 9v is all they need! (12 may be sufficient too for all I know, which isn't much)  Phantom power is only needed when you are using these capsules AND their bodies together.

In regards to using/not using the bodies, one particular thing you lose when not using the bodies in that distinct "AKG sound" as the active option that is available for those caps does not maintain that "sound." Same can be said for most other mics and their own active solution.

I am going to guess your cables are hard wired into the caps? If so, then you cannot use the bodies anymore, that is I guess if you want to hack off the cable and figure out how to get the bodies back into the equation. 

Most (if not all) other items have already been addressed so I guess I can stop there

[DigiGal]

AKG MK90/3 cables are now discontinued, but these were an OEM option for remote mounting their Blueline capsules by connecting them to the SE300B bodies.

They don't pop up for sale used often but you may want to keep an eye out for a set. 

[lsd2525]

Thanks. The cables are hard wired to the caps. I'm happy with the setup; I would like to explore an inexpensive pre that would had some "brightness" or "sizzle" on the top end. I'm happy with the results I'm getting but I do have to increase the treble on playback to get the sound I want. Have not really tried this in post; I've just been bumping up the top three freq's with a graphic EQ on my playback rig.

I have the same issue with my AT853's also......

Any recommendations on a pre that would add "brightness"? Bonus points it it puts out 9v so I can ditch the box. Since the 853's run on 9v and have mini xlr's too I'm thinking I could use the same pre to run either set.