Nice, cheap, easy LDC - way better than any BM700/800 mod

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k brown

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Get yourself a now-discontinued AKG Perception 120 (or P120; I've taken them both apart and could see no difference, even though some reviews claim the P120 has an externally polarized capsule), and just drop in this large electret (discovered by kingkorg - $8.50, get 'em while they last). 25mm Large Diaphragm Microphone Cartridge Core Recording Condenser Mic Capsule | eBay

The original capsule is literally the exact same cheap Transound electret SDC in the same, cheap gold-painted plastic ring as the Samson C01. But the mic's electronics are quite fine.

If the capsule mounting post is rotated 90 degrees in it's rubber bushing, the new capsule can be mounted in a simple loop of brass strap. I ran a strip of self-adhesive craft foam around the outside of the capsule for a bit of additional mechanical isolation (the rubber-mounted post doesn't provide much). After assy, I damped the mounting post/brass strap by covering it with 3M Mastic Tape (not shown in photo).

Unlike the BM700/800s, the AKG has a proper dome under the capsule, a heavy, solid body and lo cut and pad switches; unlike the P220, it is transformerless output.

Sounds very,very close to the AKG P220 with kingkorg's capacitor mod; very slightly less bright (but not as quiet):
https://groupdiy.com/threads/akg-perception-p220-to-neumann-u87-5-min-mod-p200-p100-p400-p420.67473/
Also, noticeably smoother than my AT2035 (that could be more due to the AT's tranformer than the capsule or electronics).


For a little more dough (~$20), this big boy (34mm) is even better, and quieter ( I may even like it better than the modded P220):
https://micbooster.com/jli-microphones/266-jli-3412-cardioid-electret-microphone.html
 

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Get yourself a new or used AKG Perception 120 (NOT the USB model), and just drop in this large electret (discovered by kingkorg - $8.50, get 'em while they last). 25mm Large Diaphragm Microphone Cartridge Core Recording Condenser Mic Capsule | eBay

The original capsule is literally the exact same cheap Transound electret SDC in the same, cheap gold-painted plastic ring as the Samson C01. But the mic's electronics are quite fine.

If the capsule mounting post is rotated 90 degrees in it's rubber bushing, the new capsule can be mounted in a simple loop of brass strap. I ran a strip of self-adhesive craft foam around the outside of the capsule for a bit of additional mechanical isolation (the rubber-mounted post doesn't provide much). After assy, I damped the mounting post/brass strap by covering it with 3M Mastic Tape (not shown in photo).

Unlike the BM700/800s, the AKG has a proper dome under the capsule, a heavy, solid body and lo cut and pad switches; unlike the P220, it is transformerless output.

Sounds very,very close to the AKG P220 with kingkorg's capacitor mod; very slightly less bright (but not as quiet):
https://groupdiy.com/threads/akg-perception-p220-to-neumann-u87-5-min-mod-p200-p100-p400-p420.67473/
Also, noticeably smoother than my AT2035 (that could be more due to the AT's tranformer than the capsule or electronics).


For a little more dough ($21), this big boy (34mm) is even better, and much quieter:
https://www.jlielectronics.com/microphone-capsules/jli-3412/
Have you compared the JLI-3412 to the JLI-2555BXZ3? If the 3412 were less bright I'd be interested.
 
Can't say how it will fare with considerable polarzation voltage on it (grid leakage from the tube) - I did it with a pair of Oktava MK-012s.

Will probably need a cap between tube and capsule.
 
For those of us outside the US, JLI shipping charges make their products stupidly expensive .... That 34mm capsule looks really interesting (even if the data sheet is mostly nonsense!)
Capsule is actually TSB-3412; made by Transound; can you order directly from them?
 
Ah, that's better . . . "ME-10" replaced with JLI3412 34mm electret (see up-thread).

This is now one fine sounding mic!

As before, the mounting post was damped with 3M Mastic Tape after taking photo.

I think it sounds better than the P220, for half the cost; virtually indistinguishable from my AKG C 3000 B with the 'kingkorg mod'.
https://groupdiy.com/threads/akg-c3000b-5-min-mod-awesome-mic.67911/
Total expenditure: $72! (P120 on eBay, $51; JLI3412 capsule, $21).
Time for mod, maybe 1 hour, max (if you're at all handy with hand tools) - no electronics mods needed.

(Can't say I'm crazy about that ice-blue body, though.)
 

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From this . . . to this - for twenty bucks and few drops of sweat.

Yes, that's really the capsule from the AKG Perception 120 on the left, without it's 'gold ring'.
 

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Yes, that's really the capsule from the AKG Perception 120 on the left, without it's 'gold ring'.

RIGHT! I found a similar, if not the same, capsule arrangement in the Behringer C-1 and Samson G-Track USB microphones - and both were similarly improved by installing the same Transsound capsules. I eventually also replaced the C-1 circuit with an Alice OPC board which provided additional improvement. James - K8JHR
 
RIGHT! I found a similar, if not the same, capsule arrangement in the Behringer C-1 and Samson G-Track USB microphones - and both were similarly improved by installing the same Transsound capsules. I eventually also replaced the C-1 circuit with an Alice OPC board which provided additional improvement. James - K8JHR
Some cheap t.bone mics use this capsule arrangement, too.
 
@k brown Did you use the 120's original capsule wires or your own? Or did the 3412 come with its own?

Would you mind also sharing a pic of how you configured the 3M Mastic Tape? I want to add it but mic and capsule with shipping I'm at $100 already so if I add the $30 to get the tape I want to make sure I place it properly.

Thanks, excited to give this a shot!
 
@k brown Did you use the 120's original capsule wires or your own? Or did the 3412 come with its own?

Would you mind also sharing a pic of how you configured the 3M Mastic Tape? I want to add it but mic and capsule with shipping I'm at $100 already so if I add the $30 to get the tape I want to make sure I place it properly.

Thanks, excited to give this a shot!
Used the wire already in there. I think the 3412 is available both ways.
 
I've just seen photos of the circuit board in the USB model, with a big IC and a bunch of other stuff in there, so don't know if it sounds as good; since it also uses an electret capsule, I'm sure the mod will work, I just can't attest to whether it will sound the same.
 
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@k brown Did you use the 120's original capsule wires or your own? Or did the 3412 come with its own?

Would you mind also sharing a pic of how you configured the 3M Mastic Tape? I want to add it but mic and capsule with shipping I'm at $100 already so if I add the $30 to get the tape I want to make sure I place it properly.

Thanks, excited to give this a shot!
Sorry - I neglected to answer the second question -

Nothing fancy, just glopped it around the post/brass strap assy.

The stuff has a lot of stretch-back when you mould it into place - you have to press/stretch it a bit farther than you want it to be so it can 'retreat' a bit. Coax-Seal is more easily mouldable; it doesn't shrink back like the 3M stuff, but it's not as firm, so not as supportive for certain applications.
https://www.amazon.com/Coax-Seal-Moisture-Proof-Sealing/dp/B00075J4J6
Here's a cheaper one; I've used it, too. It's quite soft; no shrink-back.
https://www.amazon.com/Skywalker-Si...al&sprefix=coax+sealant,industrial,159&sr=1-3
 

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