'Country Boy's' fig-8 LDC

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k brown

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With apologies to Dave Royer for appropriating his article title.

Having occasional use for fig-8 mics and my vintage ribbons just never being quiet enough, and inspired by the construction of the Neumann KM 66/76/86 (and other, much lesser mics) I modded my two Monoprice LC100s with back-to-back 'ME-10' LDC electret capsules. Diaphragms are 20mm apart.

The most 'Country Boy' part is the way the capsules are mounted to each other and to the saddle: Scotchmount Extreme Mounting Tape (very tough rubber tape with very strong adhesive on both sides) and toothpicks!! https://www.amazon.com/Scotch-Mount-414H-3PK-DC-Tape-Black-Count/dp/B09XJCXRVQ/ref=sr_1_10?crid=1523AM25SSKKV&keywords=scotch+mount+tape&qid=1672710080&sprefix=scothmount+tape,aps,263&sr=8-10 The toothpicks are the painted ones, so they stick to the mount tape very well - unpainted ones probably wouldn't as well.

Despite the daft appearance, it's actually very secure (I can shake the mic pretty violently and nothing comes even slightly loose). Since nothing's hard mounted to anything else, there's also a fair degree of acoustic isolation. Still might be good to add a bit of foam at top to wedge against the head basket, as with the KM86.

Very smooth, rich sound with excellent side null.

Some interesting info on back-to-back cards as figure 8: Neumann KM 86 | RecordingHacks.com

I said it a'fore, and I'll say it again - thanks to kingkorg for giving the first heads up about these capsules.

I know, I know - there's no deflector disc between the capsules, but hey - this is 'Country Boy'!
 

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That's correct :) I was going to put the capsules back to back, as closely as practical, using 3 short strips of tape holding them in place relative to each other. Same for creating an ersatz base.

I think your method is a better way to go, after seeing how you did it!

Edit: there's a lower cost version of the same stuff as FS, under the Gorilla brand. It's also single sided; fairly cheap at Wally World. If the 3M tape is like either of these, it's super sticky and durable - in fact hard to remove after it sets in. Fun fact: the 4" wide version is useful for taping up damage to a canvas convertible top.

https://www.walmart.com/ip/Gorilla-Waterproof-Patch-Seal-Black-Tape-4-inch-x-10-foot-Roll/293956532
 
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With apologies to Dave Royer for appropriating his article title.

Having occasional use for fig-8 mics and my vintage ribbons just never being quiet enough, and inspired by the construction of the Neumann KM86 (and other, much lesser mics) I modded my two Monoprice LC100s with back-to-back 'ME-10' LDC electret capsules. Diaphragms are 20mm apart.

The most 'Country Boy' part is the way the capsules are mounted to each other and to the saddle: Scotchmount Extreme Mounting Tape (very tough rubber tape with very strong adhesive) and toothpicks!! https://www.amazon.com/Scotch-Mount-414H-3PK-DC-Tape-Black-Count/dp/B09XJCXRVQ/ref=sr_1_10?crid=1523AM25SSKKV&keywords=scotch+mount+tape&qid=1672710080&sprefix=scothmount+tape,aps,263&sr=8-10 The toothpicks are the painted ones, so they stick to the mount tape very well - unpainted ones probably wouldn't as well.

Despite the daft appearance, it's actually very secure (I can shake the mic pretty violently and nothing comes even slightly loose). Since nothing's hard mounted to anything else, there's also a fair degree of acoustic isolation. Still might be good to add a bit of foam at top to wedge against the head basket, as with the KM86.

Very smooth, rich sound with excellent side null.

Some interesting info on back-to-back cards as figure 8: Neumann KM 86 | RecordingHacks.com

I said it a'fore, and I'll say it again - thanks to kingkorg for giving the first heads up about these capsules.

I know, I know - there's no deflector disc between the capsules, but hey - this is 'Country Boy'!
Awesome!!!
 
I used 3 x Primo EM204 capsules for a Mid/Side mic experiment...

I decided that as the side 'figure of 8' mics were never likely to be used for any close mic applications, I could probably afford to have a c.10mm capsule mounting offset in the horizontal plane, without affecting the performance too much?.. (see photo).

Mounting like like - rather than genuinely 'back to back' - allows for the back of each capsule to be exposed completely, rather than the 'air' to the reverse side of both capsules being impeded by the presence of the second capsule.

Now whether that actually makes things better - or worse? - I'm not sure?
I've been quite pleased with the results. (I've found the EM200/EM204 capsules to be really useful electrets )...
 

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I always thought this was an interesting arrangement - Sony ECM-MS5 (very highly-regarded MS mic).

Minimizes distance between mid capsule and side pair (for sources directly in front of the mic).
 

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I did a 'Fetless' electret mid/side mic : ( some notes here: OPIC Mid/Side mic ) and for that I employed a slightly unusual way of mounting the capsules.
I think it is fairly well known that one of most effective uses for super glue ( known as 'krazy glue' in the USA, I believe)?...is for sticking rubber.

So I took a couple of rubber bands, cut off a suitable length and then stretched it - only slightly - around the mic capsule.
A small dab of super glue and you have a flexible capsule mounting that hold the capsule really well.

I did the first one a couple of years ago, and the adhesive seems to show no sign of degradation.

For the mounting pillars I used nail cuticle sticks (they look like giant toothpicks) and covered them in heat shrink sleeving.... Which also works pretty well with super glue...
The pillars are mounted into a small block of neoprene.

Cheap, flexible capsule mounting - ideal for prototypes, I've found...
 

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Very clever and resourceful.

Rubber bands only good for short term use though, as (unless they are silicone) they slacken, then rot and crumble eventually.
 

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