Uh-oh....did I just wreck this mic capsule?

[dai h.]

The interesting thing about condenser mics is, they're basically the same as piezo pickups. Too heavy a loading resistance on the capsule causes loss of low end.

But, they have much lower capacitance than a piezo pickup, so the loading resistance needs to be much higher. I heard that a good condenser mic head amp can have an input resistance of 100 gigaohms.

The Schoeps circuit-based ones seem to usually have an R or two of 1G. My MXL603S has what appears to be Teflon standoffs for the capsule to FET gate connection. I have two 603S (due to my failure to figure out I had a bad XLR cable with failing shield), and one has the standoff not firmly placed into the PCB(guess that's where some of the cheapness is showing--but it seems to work fine though).

To get that kind of impedance, things like component quality, construction quality, even quality of plastics and cleanliness start to matter. So that is one possible explanation for "Chinese highs": the bass is leaking away because of too low a load resistance.

Maybe there is something there since I've read of flux not being cleaned well in some of the Cheap condensers. I also tried a cap swap mod (suggested by Gus S.) of changing the capsule to gate and two output caps from ceramic to film. There seemed to be a slight difference (going "ssss" and "shhh" into the mic to try to accent sibilance since I thought that would be one of the most obvious things) but it's not particularly drastic and I can't say with 100% certainty. Some of the other aspects/possibilities in re: to the perceived problem highs are (according to some) a mismatch (or lack of compensation) with the combo of the style of capsule (some high end emphasis) and the amplifying Schoeps-style circuit (tending towards a clear sound and possible improper loading when driving a transformer-coupled preamp (too low an impedance--something around 35ohms) which may have been a factor when assessed subjectively.

I've got a pair of Rode NT5s and they're not too bad for the money. (I bought them on recommendation from Eric Persing.) Rode used to rebadge Chinese stuff, but they started making their own mics in Australia. Yes, they work better upside down

What I understand is that there was some tech.transfer (capsule manufacturing)from German engineers (I'm assuming E.Germany) some time ago to China, and one of the better considered capsules is made by the company with this history. Rode (and many other companies) had some of their mics built by them, and many are essentially the same thing (certain joemeek, Behringer, etc.).

[J M Fahey]

Hi gtr tech.
I'm kind of slow, but I have just noticed something:

since it came in missing its windscreen the capsule was pretty dirty.

If he used it that way, *he* killed it; you just tried your best rescue efforts in good faith.
As Frondelli said, it's not a fault of Windex, *anything* would have been useless, stop.
You have nothing to buy.
Aren't any generic Chinese capsules available for replacement?
I guess there must be just one or two manufacturers who supply everybody, as in the reverb tank market.

[dai h.]

found a couple more links on cleaning:

PSW Recording Forums: Klaus Heyne's Mic Lab => Cleaning microphone capsules?

PSW Recording Forums: Klaus Heyne's Mic Lab => capsule re-plating

Cleaning a LDC (K67-type) capsule... with pics

so far, it looks like just water (and no solvents such as alcohol, etc.) is best (see last link)

[imaradiostar]

A quick look on ebay showed lots of different capsules are available. Maybe you could try some cheap ones as an experiment or buy one of the supposed "German" ones as an upgrade. Not sure if they're to be trusted or not but it looks like there is a pretty decent selection.

jamie

[dai h.]

another link, plus an idea (last ditch) to reverse the sides (assuming dual diaphram where front and back are the same and the front is bad but back is not) :

PSW Recording Forums: Klaus Heyne's Mic Lab => Gefell Capsule Cleaning

[J M Fahey]

Since it's gold, a chemically inert metal, it should stand pure distilled water, which in turn, even without mechanically scratching (that's what swabbing is, after all), should remove *water* soluble deposits.
Problem is, whatever regular saliva contains is water soluble, by definition; but if the guy has been smoking up to a few minutes before (or even taking some puffs there) , he will shower the diaphragm with saliva carrying tar and ashes.
Even if the amount per "serving" is small, it adds up.
Don't want to even imagine what will cover it if the guy has just downed a Quad Stacked Whooper with double cheese and bacon, or even a humble burrito.

[Ronsonic]

Don't want to even imagine what will cover it if the guy has just downed a Quad Stacked Whooper with double cheese and bacon, or even a humble burrito.

We do some mic work. Sometimes these mic's come from rap clubs. Your imagination will not do justice to their condition.

[dai h.]

more:

Cannot Get a Good Sound Out Of AKG C 414 B - Page 2 - Gearslutz.com

(seems risky to use anything more than tiny amounts of water/moisture, esp. getting fluid near the edge(and between the diaphram and retaining ring) or near the center (where there is a hole in which fluid could be sucked into)--unless you have the know how and equip. to disassemble, dry and tension the capsule :

Acid Dipped Diaphram ? - Gearslutz.com

pics of what some of that involves:

Diaphragm Tensioning

DIY Audio Stuff