Matt Nolan
Well-known member
Another solution to that is to not use part legs as buses.
"U67"-ish microphone
- Thread starter RuudNL
- Start date
Help Support GroupDIY Audio Forum:
Fair. I was responding to the pictures in post #98.
I'm building an M49c on turrets right now, so I'm not opposed to getting away from PCBs. For more complex circuits and/or circuits that use a lot of transistors, PCBs seem to be cleaner though.
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Getting ready to power before connecting M7 capsules. Will I need a load to protect the transformers? Dont anticipate any strong AC signal and the cap is rated 1kV
Just want to check V readings.
And yes I anticipate hum before I get the enclosures.
Just want to check V readings.And yes I anticipate hum before I get the enclosures.
Are you building a microphone or a radio control tower?Getting ready to power before connecting M7 capsules. Will I need a load to protect the transformers? Dont anticipate any strong AC signal and the cap is rated 1kV
And yes I anticipate hum before I get the enclosures.
View attachment 126449
Just kidding! Very interesting technique, and not a bad way to test voltages. I'd anticipate that the hum will be as loud/louder than your signal though.
That plate under the capsule will affect it's frequency and pattern response in a really bad way.Getting ready to power before connecting M7 capsules. Will I need a load to protect the transformers? Dont anticipate any strong AC signal and the cap is rated 1kV
And yes I anticipate hum before I get the enclosures.
View attachment 126449
Will be 5 mm machined brass.
Bazooka ! Have ordered brass mesh and the housing is 2 mm brass.View attachment M7 Mic från sidan3_1.jpgAre you building a microphone or a radio control tower?
Just kidding! Very interesting technique, and not a bad way to test voltages. I'd anticipate that the hum will be as loud/louder than your signal though.
Doesn't help, it will cause reflections anyways, and cause cancelations in high midrange. You'll get quite substantial nulls and spikes in very audible range. If it absolutely needs to remain this way, you should elevate the capsule some more, and make a dome that would difract the soundwaves away from the capsule.
Thanks! I am aware of the problem with standing waves and coloration. Every cavity and every piece of metal has a resonance giving a "wowel" as in the vocal tract or a trumpet, ogan pipe etc. Maybe you didn't see that the top is a ring, so the paralell surface is not so big. I could slant the top ring maybe 10 degrees to deflect.
Thankfull for all suggestions.
View attachment Plates 3_2.jpg
The problem isn’t (only) with the top ring and standing waves, it’s comb-filtering caused by primary reflections off of the surface of the plate below the capsule.
Sound will enter the microphone and simultaneously hit the capsule and the bottom plate, then some of those waves will bounce off the plate and strike the capsule immediately after, causing phase cancellation with the waves that directly hit the capsule. The only way to prevent this is to do as @kingkorg said - move the capsule higher and/or add diffusion/absorption to the surface of the plate below the capsule.
