acm 1200 circuit and mods (similar to apex 460)

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Thanks!  Brian Fox at Fox Audio Research recommends 200-330 pF with the CEK-12, with 220 pF being his favorite, so, that's what I'm going to try first.  He also sent me an ELA M schematic you can actually read.  What a cool guy.
 
I ended up staying with 330pF.

I found that the modded mic did not end up too dark with that choice. It is still a bit brighter than my other fet ldc and I wouldn't want it to be any brighter.

The final mod worked a treat - it still amazes me how big the change was. It is now so sensitive, quiet and full frequency responsive it's hard to believe where this started from. A disaster!

I think my total cost was something like 420usd for the mic, mod electronics, tube and good quality sino capsule. And shipping was probably 1/3 of that cost.
 
Yes, the sonic results of this project are frankly, amazing to me.  I used Peluso capsules, for a total project cost per-mic of about $550-600 but I haven't done the actual calculation, that's a rough estimate.  That's with Gotham cables, Neutrik plugs, replacement Neutrik panel jacks (essential--tighter fit), low-noise 6072a tubes, Peluso capsules and transformers, high end caps and resistors.  Compared to buying a P-12 from Peluso I'm saving $600 per mic for a total savings for the pair of $1,200.  That's pretty incredible, to me.  If I could do the same kind of build to replace my 2247 SE, I would.  There isn't an adequate multipattern tube LDC of the right body type and size for this, currently, to my knowledge.  I suspect these mics I built might actually end up sounding slightly better than the P-12 from Peluso due to the upscale caps and high-end smoothing tweaks that I'm about to do.

Any way you look at it, this is such a rewarding project.  Someone I read said "this is the best deal going in microphones right now," but he was referring to using the Tim Campbell capsules, which I would love to, but haven't yet been able to afford.  I might, later, build a "251" with one of his transducers.  I'm really interested in attempting a Thiersch M7 mic, as well.

Thanks for the tip, I'll be sure to keep 330 pF in mind, too, when I'm doing my smoothing capacitor evaluations.  Other than the excessive high end, the Peluso CEK-12 is really a fantastic sounding capsule.  This seems to be a trend with Peluso.  I had to sell the CEMC6 because they were just, too, bright.  They, like the CEK-12 mics here, were exceptionally detailed and clear sounding, though.  My 2247 SE, however, is only occasionally too bright.  Most of the time it is very pleasantly balanced.
 

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