Km84 PCB

[Khron]

I'd say the top red circle should also enclose the schematic joints above it as well (as per the text description, R1-C9-C2-C1).

 

[jean-christophe boussin]

I just welded the capsule correctly, the microphone works very well for 10 seconds after nothing.

 

[Chrisfromthepast]

*edited/deleted. Plainly I missed the last word and misunderstood.
Can you post audio of the failure?
Sounds like a loose solder joint or the tantalum coupling cap from words.

 

[jean-christophe boussin]

the microphone works well, it is very sensitive, I have the impression of speaking in a pipe, still some crackling

 

[Chrisfromthepast]

Whats the capsule?

 

[jean-christophe boussin]

Whats the capsule?

I took a cheap capsule, I wanted to test my pcb first

 

[jean-christophe boussin]

Whats the capsule?

you have references to offer me for the purchase of a capsule, I will mainly record an electric guitar

 

[Chrisfromthepast]

Is the body one of those mxl 603s types with the white paint? Blizzard edition. I have one like that and the threads are terrible. Only a few of the 22mm capsules I have can securely fit. I chose one and taped it to remind me to not remove.
The 3U capsules at the deeper depth (3mm?) would normally work for this model of mic, but the threads were so shot on my mic, only a careful selection of mxl capsules will thread on successfully. Your mileage may vary.
If the threads are good, go for 3U

 

[Chrisfromthepast]

Crackling is more likely residual flux that needs to be cleaned with a toothbrush and 91% alcohol. Capsule might be fine. Can you post photos?

 

[titote]

I'm recording an audio extract tonight, I'll try to find how to post it on the site

 

[jean-christophe boussin]

Crackling is more likely residual flux that needs to be cleaned with a toothbrush and 91% alcohol. Capsule might be fine. Can you post photos?

a try without any treatment, the preamp is at 1/4 of its power, Focusrite 2.2, stratocaster, Marshall plexi 100 watt. There are crackles at the beginning.

 

[Chrisfromthepast]

Maybe a cold solder joint?
But it may be helpful to rule out the capsule. When you biased, could you get those crackles to appear if you increased the signal level enough? Did you go for 10V or third harmonic?
How is the noise level with just a 15pf capacitor instead of the capsule?
Any crackling when you are expecting silence or only when hitting it hard?

 

[titote]

Maybe a cold solder joint?
But it may be helpful to rule out the capsule. When you biased, could you get those crackles to appear if you increased the signal level enough? Did you go for 10V or third harmonic?
How is the noise level with just a 15pf capacitor instead of the capsule?
Any crackling when you are expecting silence or only when hitting it hard?

I have 10v at the bias, it seems to me that the crackle is still there as background noise, the microphone is very sensitive and saturates very quickly. it could be a cold weld

 

[jean-christophe boussin]

Maybe a cold solder joint?
But it may be helpful to rule out the capsule. When you biased, could you get those crackles to appear if you increased the signal level enough? Did you go for 10V or third harmonic?
How is the noise level with just a 15pf capacitor instead of the capsule?
Any crackling when you are expecting silence or only when hitting it hard?

the microphone works without cracking, it was a bad solder, I'm surprised with the result.