Need help with a TLM 102 sized PCB for DIY LDC mic

[MidnightArrakis]

Bold of you to assume someone named eden was a guy

[Bold of you to assume someone named eden was a guy] -- There is absolutely no way that anyone can assume that whatever combination of alphanumeric characters are used in someone's screen-name on this forum even remotely constitutes them to be a persons name!!! So.....if your a female.....GREAT!!! Females involved in professional audio AND electronics is certainly a rarity!!!

If you're some confused -- "trans" -- person.....well.....I feel sorry for you and wish you well. In any case.....I DON'T BUY INTO ANY OF THE CURRENT -- WOKE-SH!T -- THAT'S PLAGUING OUR COUNTRY RIGHT NOW!!! Let's just leave it at that, OK???

>> Have you downloaded the videos I have provided you with yet? Have you reviewed my KiCAD version of your schematic yet?

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[Khron]

If you're some confused -- "trans" -- person.....well.....I feel sorry for you and wish you well. In any case.....I DON'T BUY INTO ANY OF THE CURRENT -- WOKE-SH!T -- THAT'S PLAGUING OUR COUNTRY RIGHT NOW!!! Let's just leave it at that, OK???

Well this part was surely unnecessary

 

[edenooo]

Well this part was surely unnecessary

Yeah..... Not really sure what triggered that lol</3

 

[Itsme]

I agree that this circuit produces more noise than the impedance converter with SE output (assuming you are referring to the above circuit...).
Reason: the first stage has a signal gain of one (doing it's job well to adapt to the high impedance source characteristics of the capsule). It also has a noise gain of one.
The second stage has a signal gain of (-) 1 but a noise gain of two - which indeed is not great...
The noise characteristics of the whole circuit would get a lot better if the first amp had some gain already. best would be it would amplify the signal to the highest desirable level and then either exit the mice single-ended or add add an inverter for differential transmission (considering the appropriate gain for that configuration). Note that the noise gain counts. Example: the first stage has a gain of 6 the second -1 (noise gain=2) the calculation would be: sqrt (6^2 +2^2) -> sqrt 40=6.32 (or 0.95 times the dynamic range of the SE version). This means the 2nd stage adds only about 5% to the overall noise.
As a bonus (in this example) the gain (and noise) of the rest of the signal chain could be reduced by a factor of 6 increasing the dynamic range by (almost) 6x.
In comparison the above circuit would give you sqrt (1^2+2^2) -> 1.73 or 0.58 times the dynamic range.
This isn't entirely correct as I only considered the voltage noise contribution of the amplifiers while the first stage would also have some contribution due to current noise (hence only 3dB more noise).