MXL 9000 (Frankenmic) assistance please....

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tchgtr said:
Maybe a smaller value than the 9pf that was in there would make less of a hi cut...

Yes, it would shift the cut-off. Depends where you want roll off, and at what rate depending on if you want to use just a cap...
 
I removed the filter network on the secondary of the transformer and the mic won't pass signal but the tube lights up and warms.

Due to needing a working mic, I removed the capsule and put it in an MXL 990 with the Gus Smalley mod.

I kind of want to send it to a tech who can get the mic working.

I may just send it off to John Peluso.

In the process of putting the mk319 capsule in the mxl 990, my Peluso CEK12 was rendered homeless and i didn't need it as much since the v76t i got back from john peluso with PK67 capsule is pretty bright but controlled, i figured i'd let it go.

Does anybody want a CEK12 Peluso capsule? I used it maybe all of 10 times, it mostly sat dormant in the mic in the case.

I'm selling it for $150 with mounts (saddle and throne w/screws) and free shipping, no paypal fees.

Peace
Illumination
 
illacov said:
I removed the filter network on the secondary of the transformer and the mic won't pass signal but the tube lights up and warms.

Sure it won't. You need to put wire jumpers in place of R20, R21, and L1, L2.

Best, M
 
Thanks, I thought it might be that but....I'm not exactly the best informed on this.

Getting something worked out with a tech anyhoo, they'll address this, plus do some other mods apparently :)
Thanks everybody for the help and patience you've shown me. It was very enlightening and apparently pretty helpful to others.

We should do a similar thread for the V76t which despite being similar is not quite the same mic.

Peace
Illumination
 
    I removed the R20, R21, C20, C21, and L1 and L2 from my 9000. My first impressions are that it's a bit more mid-rangey than before (after the mods mentioned earlier), but it may be my listening environment. I'll make some recordings later, through the same signal chain as my other tests, and see how it compares.
  Instead of bridging the gaps with wires, I moved the output wires to the solder pads that meet with the wires coming from the tranny to reduce extra wire in the circuit.
  The mic has the classic tube-mic response, which shows me how poorly insulated for sound my studio room is. Sounds from other rooms and outside (computer, fridge, TVs, planes, cars, etc.) are painfully obvious, and I live in a relatively quiet neighborhood...
Sibilance is not too bad, and that clean tube hi end is very nice, especially now with more stuff removed from the circuit. The noise level of the mic seems to be reduced a bit, too, which might be why I am noticing this even more than previously.
  As a side note, I took Rodabod's  advice (very good, I thought), and replaced the 9 pf cap back into the circuit. To make a long story short, it was no good, and may have been part of the problem with the mic all along. After warming up, the mic began to hiss and spit at quite a loud volume level. Since I did this at the same time as the removal of the aforementioned parts, it took me a while to trace the problem. 
  Chalk it up as a lesson about the delicacy of small value caps in tube circuits. I thought my solder touch was good, but maybe I burned it a bit.
  The mic made these same noises to a lesser degree when I first got it (used and abused), but I thought I had repaired it when I found a stressed wire coming from the tube socket.
It's a whole new mic now, and much better than before. It's given me a good education.

Thanks all...
Jim
 

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