Is there any reason to still use electret capsules?

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Icantthinkofaname

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Now that there are a lot of affordable true condenser capsules in both large and small sizes (and for cheap if you're willing to use WGTCenter or get samples from 797) as well as a lot of available schematics for projects, is there any reason to still use electret capsules?

I know companies like DPA use really high quality electrets, but I'm mostly talking about the affordable but good ones like Primo (I'm quite interested in the EM200 and EM204), Transound (I like the TSB2555), etc.

This isn't really for any specific project, but I thought I'd start a discussion on it, partially because I'm interested in the old American CAD Equitek mics like the E200 and E100.
 
No DC biasing required? That removes the need for a couple resistors and (arguably "pricey") capacitors...
 
I've found electrets - like the EM204 - very useful  for projects like Mid-Side mics.
The fact that there's no need for either external polarisation voltage circuitry - or indeed even for an external impedance converter  - means there's a lot less circuitry to fit into a 'donor' body for example...

The attached schematic  shows just how simple an M-S mic can be with electrets - and works pretty well!
 

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RuudNL said:
Nice and simple design.
And yes, the Primo capsules are excellent!
I've been debating getting a used CAD E200, which I believe used two Primo EM204s, but I've heard a lot of stories of CAD mics suddenly dying out of the blue. And I certainly prefer the sound of the old E100 over the E100S (M179 over E100S as well).

I guess they could be pretty easily put into a donor body, but I don't know of any multipattern electret donor mics (besides the Behringer C3 or Samson C03, but I don't know how good the stock components are). Though I know Khron has his multipattern build using the BM-800 body, I just wouldn't know what to leave out with a pair of electret capsules.

It's too bad cheap electret SDCs don't go with good capsules and just charge more. The iSK Little Gem and Superlux multi capsule electret SDC (basically the Samson C02 with cardioid, hypercardioid, and omni) could've used some.
 
RuudNL said:
Nice and simple design.
And yes, the Primo capsules are excellent!

Larger Primos capsules - like the EM204 are indeed pretty good (although not that cheap!)  - perhaps not quite in the 34mm LDC class though?..

I've tried them out in a M-S mic built into a BM800 body, and have been quite pleased with the results.
I also get both a cardioid and a figure of 8 from the same mic, should I prefer to make recordings that way!

Capsules are mounted using rubber grommets and heat shrink sleeving covered cotton bud stems - with a 4mm neoprene base .. (see attached image).
The 'side' (or figure of 8 ) capsules are not quite coincident, but are only  offset by a few mm , so it's not really a problem.
The circuitry - as per my schematic above - was simple enough to mount straight onto stripboard.....
 

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rogs said:
Larger Primos capsules - like the EM204 are indeed pretty good (although not that cheap!)  - perhaps not quite in the 34mm LDC class though?..

I've tried them out in a M-S mic built into a BM800 body, and have been quite pleased with the results.
I also get both a cardioid and a figure of 8 from the same mic, should I prefer to make recordings that way!

Capsules are mounted using rubber grommets and heat shrink sleeving covered cotton bud stems - with a 4mm neoprene base .. (see attached image).
The 'side' (or figure of 8 ) capsules are not quite coincident, but are only  offset by a few mm , so it's not really a problem.
The circuitry - as per my schematic above - was simple enough to mount straight onto stripboard.....
I think it depends on the capsule and circuit too. I like the vintage CAD E100 (Primo EM204 I think) a lot more than the E300² (and E300S) and M179.

I'd actually really love to get my hands on some of the Earthworks and DPA mics with electret capsules, but they're out of my budget right now.

Are the Primo capsules the best electrets easily (both ease of purchase and pricewise) available to the DIY community?
 
Icantthinkofaname said:
I guess they could be pretty easily put into a donor body, but I don't know of any multipattern electret donor mics (besides the Behringer C3 or Samson C03, but I don't know how good the stock components are).
I once had a Behringer C3 here, but it was the worst microphone I have ever seen. (And heard...)
Capsules sounded like nothing and the microphone was so noisy, that you could only use it to record (loud!) hardrock.
It sounded like you were standing near Niagara Falls.
There was even nothing that was worth keeping, so the microphone ended in the bin.
 
Icantthinkofaname said:
Are the Primo capsules the best electrets easily (both ease of purchase and pricewise) available to the DIY community?
That certainly seems to be the case here in the UK ..... I've had several different types of Primo capsules from Micboosters and have been very pleased with all of them...
 
I ordered from Micboosters in the past. They offer a good range of Primo capsules.
A bit annoying is that it seems they are closed for a couple of weeks from time to time at unexpected moments.
 
RuudNL said:
I once had a Behringer C3 here, but it was the worst microphone I have ever seen. (And heard...)
Capsules sounded like nothing and the microphone was so noisy, that you could only use it to record (loud!) hardrock.
It sounded like you were standing near Niagara Falls.
There was even nothing that was worth keeping, so the microphone ended in the bin.
I've heard people say the use quality components, maybe in the super early ones, but I still kind of doubt that. 23 dBA is pretty high for a studio mic. I sold my iSK Little Gems on eBay because I decided I didn't want to try modding them, because I figured a lot of the noise came from the capsule (since they seemed to have good components in the circuit, noise was 24 dBA, which is a lot to begin with for a mic intended for studio recording, especially when it didn't have a particularly strong output). I didn't really want to grind off the grille, take out the capsule, and try to put in a better electret capsule. That's too much effort for me when there are other budget SDCs for $100 that I don't have to mess with (they weren't bought with the intention of modding, just on recommendations of them being good on Gearslutz, though I'm sure anybody who actually had the skill could mod them). I had really only bought those to use while trouble shooting the Chinese MK-012s I bought. No idea where I put those capsules, I stuffed em in a ziplock bag with some silica gel after I got my Russian capsules. Would've loved to have taken the Chinese capsules apart, which I'll still do if I find them.

Anyway, I think the EM204 would be pretty good in a small diaphragm mic. It's too bad they don't have a similarly sized omni capsule (biggest I can find is 10mm, and the 10mm cardioids are either super noisy or they have a really big boost in the treble).
 
That’s the thing with SD electrets, most of them are either limited in response or noisy. I’m actually always on the lookout for a 4mm electric cardioid or omni with a reasonable noise-floor and a response flat or + to at least 20k... Haven’t found one that’s not inside an expensive, fully-designed mic yet.
 
Recording Engineer said:
That’s the thing with SD electrets, most of them are either limited in response or noisy. I’m actually always on the lookout for a 4mm electric cardioid or omni with a reasonable noise-floor and a response flat or + to at least 20k... Haven’t found one that’s not inside an expensive, fully-designed mic yet.
I'd really love a clone of whatever's in the Earthworks mics, but they're not exactly going to give Chinese mic manufacturers their secrets.

I've toyed with the idea of trying to modify the holes on TSB2555s since they're so cheap.
 
Icantthinkofaname said:
It's too bad they don't have a similarly sized omni capsule (biggest I can find is 10mm, and the 10mm cardioids are either super noisy or they have a really big boost in the treble).

The Primo EM172 Microphone Capsule is omni and has a pretty low noise (14 dBa)
 
So, I had a probably not very original thought. If I were going to try to build a mic similar to the Earthworks ones, which capsules should I go for if I don't want to mod the old Panasonic ones? And are there donor measurement mics like that, or would I be cutting/drilling vents into a cheapo T.Bone MM1 (to make a cardioid mic with a cardioid capsule) or similar Chinese measurement mics?
 

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