MBHO CK12 Capsule--KA1000N and KA1100?

[C12VR]

Well that capsule is cardioid only so I think the graph must be a very poor representation of 0 degrees compared to 180 degrees.

ah yes you're right. The shape looked similar at first glance, but it's definitely different. Incorrect for sure.

 

[hop.sing]

Your measurement of the MBHO capsule looks correct. They have a bump in the mids which really makes them deviate from an AKG.

That capsule was originally designed to only be polarized to 48v.

Thanks for confirming that the capsule (and my measurement setup) works ok, the mic definitely sounds good.
What is the consequence of the 60v compared to the 48v polarization voltage?
The capsule does not collapse so technically it works.
Since b+ is adjustable in that mics power supply I could lower it just for fun to 100v and have a listen and measure it. The tube should still be happy…
I will try and report.

 

[Tim Campbell]

Thanks for confirming that the capsule (and my measurement setup) works ok, the mic definitely sounds good.
What is the consequence of the 60v compared to the 48v polarization voltage?
The capsule does not collapse so technically it works.
Since b+ is adjustable in that mics power supply I could lower it just for fun to 100v and have a listen and measure it. The tube should still be happy…
I will try and report.

When David Bock first started using MBHO capsules they all collapsed and so he got them to change it so that it could tolerate 60v. I ask that users polarize my capsule to 55v. A 5v drop doesn't lower volume or increase noise but I find that the capsule sounds better at 55v and could extend it's working life.

 

[Tim Campbell]

Just one shipment on my bench today for repair.

 

[RuudNL]

I ask that users polarize my capsule to 55v. A 5v drop doesn't lower volume or increase noise but I find that the capsule sounds better at 55v and could extend it's working life.

The difference between 60 V and 55 V is theoretically 0.8 dB, so this can be neglected.

 

[hop.sing]

When David Bock first started using MBHO capsules they all collapsed and so he got them to change it so that it could tolerate 60v. I ask that users polarize my capsule to 55v. A 5v drop doesn't lower volume or increase noise but I find that the capsule sounds better at 55v and could extend it's working life.

I checked the Microphone and B+ was actually at 128 Volts, so I had 64 Volts on the capsule probably for a long time now. It never collapsed, even on loud sources like 1 meter outside a kikdrum or drum overhead, where I had to Pad the mic to not overload the Preamp, so maybe my MBHO capsule is not the stock one but already modified for higher Voltage. They knew I would put it in a mic with 60V polarisation, so they could have given me a capsule ready for that... I remember talking to Mr Haun on the phone at that time and he was a caring and lovely Person to talk to. I will lower the voltage anyway, because I heard or measured no difference at 115V B+ except 1.3 dB lower Level and that is easily acceptable for me.

 

[paulcheeba]

Up until now I’ve been most impressed with Haun capsule’s in general. The dark Bock one especially. Now I feel that the Austrian Audio are the closest to my original C12’s it’s a shame they don’t make them for DIY. I find others too fizzy, bright and lack depth. It’s frustrating given how easy the centre terminated capsules seem to sound good.

 

[Tim Campbell]

Up until now I’ve been most impressed with Haun capsule’s in general. The dark Bock one especially. Now I feel that the Austrian Audio are the closest to my original C12’s it’s a shame they don’t make them for DIY. I find others too fizzy, bright and lack depth. It’s frustrating given how easy the centre terminated capsules seem to sound good.

Paul I find that interesting. Austrian Audio's own frequency charts show that that capsule doesn't have the same frequency response as a classic brass CK12. They have a peak at 5k and a very deep dip at 8k that the CK12 never had. The peak at 8k is greater than the peak at 11k and there is almost no peak at 10k. I measure vintage capsules all the time, a classic CK12 is pretty flat until just after 2k, has a gentle rise until around 7k, levels off and then rises again until around 11k and then rolls off. I will have to check out this capsule to see why you prefer it's sound.

 

[paulcheeba]

Paul I find that interesting. Austrian Audio's own frequency charts show that that capsule doesn't have the same frequency response as a classic brass CK12. They have a peak at 5k and a very deep dip at 8k that the CK12 never had. The peak at 8k is greater than the peak at 11k and there is almost no peak at 10k. I measure vintage capsules all the time, a classic CK12 is pretty flat until just after 2k, has a gentle rise until around 7k, levels off and then rises again until around 11k and then rolls off. I will have to check out this capsule to see why you prefer it's sound.

It just sounds sweet to me like a real C12. Not brittle or overly bright and sibilant. I don’t look at charts I just listen.

 

[Tim Campbell]

It might be that you like it because it is very similar to the frequency response of a K47 Neumann capsule. They also sound good.

 

[paulcheeba]

It might be that you like it because it is very similar to the frequency response of a K47 Neumann capsule. They also sound good.

Well it doesn't naturally have so much low end and it's not a tube mic but the top end which is where I'm focussed on CK12's is sweet and clear. A small eq adjustment can match them.