Microphones

[Grider Pirate[_2_]]

Most of the boom microphones are Dynamic, while the headset type
microphones are 'standard'. I get that the 'standard' mike is quite
small, and fits in a headset boom. Is the dynamic element in the boom
mikes preferred because of the audio quality? From time to time I
hears someone on 23.3 that has such good clarity that you'd think
they're in a sound studio. One of these days I'll find out what their
setup is!

[John Carlyle]

It's my understanding that the "dynamic" microphones are really capacitive microphones. This is indeed the design that sound studios use. The "standard" microphones are based on the carbon resistor principle used by Alexander Graham Bell. While they are very rugged, they don't offer the highest sound quality.

There are other factors that affect the quality of the transmission. One factor is the percent of modulation, which if not set properly causes the received sound wave to be distorted by "clipping" (it would have flat tops if seen on an oscilloscope). Percent modulation is usually best set by an avionics tech.

But another sound quality factor is the position of the microphone with regard to the pilot's mouth. If you speak directly into the microphone you can distort the sound - it's better to speak across the microphone. The microphone position is of course under your control, so it may be quite easy to improve your transmissions.

-John

[John Carlyle]

Thanks for the correction. Of course, it's the Electret type that's the capacitive microphone, not the dynamic.

-John

On Friday, December 7, 2012 5:51:19 PM UTC-5, Tim Newport-Peace wrote:
> Dynamic microphones are Moving Coil microphones, not Capacitive.
>
> 'Standard' microphones as used in aviation are usually Electret type
> made to look (electronically) like Carbon Microphones. >
> Tim Newport-Peace

[Darryl Ramm]

On Friday, December 7, 2012 2:25:17 PM UTC-8, John Carlyle wrote:
> It's my understanding that the "dynamic" microphones are really capacitive microphones. This is indeed the design that sound studios use.

While we are on corrections. There is really no such thing as a type of microphones "studios use". Go into any recording studio and you'll see a mix of dynamic, condenser and ribbon microphones used for recording anything from vocals to guitar cabinets to drums (and on a singe drum kit you might have all types of microphones used at once). And every now and again you'll see things like a speaker used as a microphone on a kick drum,... just an oversized dynamic mic.

And if anything high-end vocal studio mics tend to be condenser not dynamic types, e.g. require phantom power and are more sensitive than dynamic mics.. But even for vocals you'll potentially see all types used.

Darryl

[[email protected]]

Copy that. Too bad the manuals aren't typically very forthcoming in providing ideal microphone impedance.
Thank you for the link.


>
>
> What you are probably hearing as 'good clarity' is a microphone well
>
> matched to the transceiver.
>
>
> There is a very good explanation about microphone types at:
>
>
>
> http://www.bas.uk.net/data4.html
>
>
>
> Tim Newport-Peace
>
>
>
> "Indecision is the Key to Flexibility."

[Peter Higgs]

At 23:27 08 December 2012, Darryl Ramm wrote:
>On Friday, December 7, 2012 2:25:17 PM UTC-8, John Carlyle wrote:
>> It's my understanding that the "dynamic" microphones are really
>capacitiv=
>e microphones. This is indeed the design that sound studios use.=20
>
>While we are on corrections. There is really no such thing as a type of
>mic=
>rophones "studios use". Go into any recording studio and you'll see a mix
>o=
>f dynamic, condenser and ribbon microphones used for recording anything
>fro=
>m vocals to guitar cabinets to drums (and on a singe drum kit you might
>hav=
>e all types of microphones used at once). And every now and again you'll
>se=
>e things like a speaker used as a microphone on a kick drum,... just an
>ove=
>rsized dynamic mic.
>
>And if anything high-end vocal studio mics tend to be condenser not
>dynamic=
> types, e.g. require phantom power and are more sensitive than dynamic
>mics=
>.. But even for vocals you'll potentially see all types used.
>
>Darryl
>

A bit off subject, but,,,, I remember my old school had a new system of
Tannoy Loudspeakers installed in each of the classrooms.

Our head teacher would give use the usual morning pep-talk, always starting
with slurp, slurp, 'Attention boys this is your Headmaster speaking'.
slurp.

What I found out when visiting his study, was that the loadspeakers could
be turned into microphones by a click of a switch, so he could monitor each
class in turn... What a Crafty So and So...

[Wheaton]

On the subject, I have any issue transmitting. When I key the mike to talk, I am told the carrier breaks but there is no modulation. Becker 3201 with very little air time. Any ideas? Radio was in the shop for new internal battery and paperwork indicates a basic transmit/receive check. Checked connector on back of radio and at speaker box (dittel).