mic help

[1iwilly]

I recently picked up a Heil MH-12 Genesis mic with a 4-pin connector, and I'm trying to use it with my FT-890. The only adjustment I could make on my radio is pressing Fast + USB to reduce some of the bass, but the mic still lacks treble. I remember an old trick for CB mics where you take a .01 ceramic capacitor and place it across the positive and negative terminals of the cartridge. Does anyone have any other tips or tricks I can try?

 

[brandon7861]

Did you try the capacitor trick? Did it help?

If I had to guess how that cap trick worked, I would assume it is different for every mic as every dynamic mic has a different inductance. According to the internet, that mic has a dynamic element. Not sure tossing a 10nF cap across a random mic element is going to do what you want.

Can you measure the inductance of it? If you know the inductance, you can calculate the reactance of the element at treble frequencies, and then choose a cap that has equal reactance at that frequency to parallel across the mic element. This would cause a resonance at the treble frequencies and, I believe, boost them.

 

[doffo]

I recently picked up a Heil MH-12 Genesis mic with a 4-pin connector, and I'm trying to use it with my FT-890. The only adjustment I could make on my radio is pressing Fast + USB to reduce some of the bass, but the mic still lacks treble. I remember an old trick for CB mics where you take a .01 ceramic capacitor and place it across the positive and negative terminals of the cartridge. Does anyone have any other tips or tricks I can try?

Unsure if there is much you can do. even the eham reviews had a couple where:
"Inherently, bass voice tones are VERY emphasized while mid-tones are muddy. High tones, despite the claimed brightness boost at 2 KHz, are almost missing. Hence clarity and the brightness clarity requires is just not there."

another review mentioned:
"With those settings, I plugged the HM-12 in, thinking is should be not quite a sharp, same amount of Gain to drive the transmitter. Boy was I surprised, Muffled, Bassey Audio galore. Hardly any Highs, had to turn the TREBLE to +5 & the BASS all the way down to Minus 5. Now it sounds pretty good, actually like a Muddy sounding Goldline. Articulation in a separate receiver just wasn’t there with the advertised 4db Boost at 2000 hz, like the Goldine. Somethings wrong with this Mic? Needs a $300.00 Equalizer! That’s what everybody does, EQ it!"

Guess you may as well get an EQ and try to make use of it.

That might be the problem with the mic itself.

 

[nomadradio]

A capacitor in parallel with the audio wire will cut treble. A capacitor inserted in series with the audio wire will cut bass.

Might start with a .01 or .05 uf and see if it sounds better.

73

 

[1iwilly]

A capacitor in parallel with the audio wire will cut treble. A capacitor inserted in series with the audio wire will cut bass.

Might start with a .01 or .05 uf and see if it sounds better.

73

will give that a try later on thanks nomad

 

[1iwilly]

ok, i use a .01 cap, which seems to help lower some bass but to me, it almost has like a tad of nasally sound.

 

[nomadradio]

Adding a capacitor from the audio signal to ground will cut the highs. Might or might not help the "nasally" sound. Might try larger values than .01 for the series cap and see if the tone is better balanced.

It's like pin-the-tail-on-the-donkey, but without the blindfold.

73