hello,

i was reading this month's Recording magazine. There was a DPA mic
review. DPA had a quote saying something like "the capsule is so small
that it automatically puts out a pure omni so you don't need a polar
plot."


Does this infer that smaller diaphragms on mics have a better ability
to create an omni pattern?

On 20 Jan 2005 12:46:58 -0800, wrote:

hello,

i was reading this month's Recording magazine. There was a DPA mic
review. DPA had a quote saying something like "the capsule is so small
that it automatically puts out a pure omni so you don't need a polar
plot."


Does this infer that smaller diaphragms on mics have a better ability
to create an omni pattern?

Yes, although the dimensions of the housing play a large part too. If
you could reduce a mic to a point, it would be a perfect omni.

d

Pearce Consulting
http://www.pearce.uk.com

wrote in message
oups.com
hello,

i was reading this month's Recording magazine. There was a DPA mic
review. DPA had a quote saying something like "the capsule is so
small that it automatically puts out a pure omni so you don't need a
polar plot."


Does this infer that smaller diaphragms on mics have a better ability
to create an omni pattern?

Yes.

Omnis used in recording range between 1 inch and a half inch, with a few
quarter inch and even tenth inchers.

1 inchers are definately directional at high frequencies and therefore qre
often thought to need some built-in treble boost to sound balanced in the
mid and far field. Half-inchers and smaller need very little *help* of that
kind.

OK....how many of you chuckled a bit when reading Arny talk so
seriously about 1 inchers, half-inchers and the like......
later,
m

wrote in message
oups.com
OK....how many of you chuckled a bit when reading Arny talk so
seriously about 1 inchers, half-inchers and the like......
later,

Exactly what do you mean?

In article ,
Chel van Gennip wrote:

If you reduce the size of the diaphragms
you have less sound energy, so more noise, mechanical problems etc.

Not true. A small diaphragm capsule is less noisy than a large diaphragm
capsule on average.

-Todd

On Thu, 20 Jan 2005 16:00:02 -0500, Arny Krueger wrote
(in article ):

wrote in message
oups.com
hello,

i was reading this month's Recording magazine. There was a DPA mic
review. DPA had a quote saying something like "the capsule is so
small that it automatically puts out a pure omni so you don't need a
polar plot."


Does this infer that smaller diaphragms on mics have a better ability
to create an omni pattern?

Yes.

Omnis used in recording range between 1 inch and a half inch, with a few
quarter inch and even tenth inchers.

1 inchers are definately directional at high frequencies and therefore qre
often thought to need some built-in treble boost to sound balanced in the
mid and far field. Half-inchers and smaller need very little *help* of that
kind.



OTOH, the smaller the diaphragm, the louder the selfnoise.

Regards,

Ty Ford



-- Ty Ford's equipment reviews, audio samples, rates and other audiocentric
stuff are at www.tyford.com

On Thu, 20 Jan 2005 22:29:30 -0500, Todd Lipcon wrote
(in article ):

In article ,
Chel van Gennip wrote:

If you reduce the size of the diaphragms
you have less sound energy, so more noise, mechanical problems etc.

Not true. A small diaphragm capsule is less noisy than a large diaphragm
capsule on average.

-Todd

That is absolutely FALSE. Selfnoise (all thing being equal) varies indirectly
with the size of the diaphragm. The smaller the diaphragm, the louder the
selfnoise.

Why? Simple physics. The movement of smaller diaphragms produces smaller
voltages differences that those of larger diaphragms.

Sorry.

Ty Ford



-- Ty Ford's equipment reviews, audio samples, rates and other audiocentric
stuff are at www.tyford.com

In article ,
Ty Ford wrote:

On Thu, 20 Jan 2005 22:29:30 -0500, Todd Lipcon wrote
(in article ):

In article ,
Chel van Gennip wrote:

If you reduce the size of the diaphragms
you have less sound energy, so more noise, mechanical problems etc.

Not true. A small diaphragm capsule is less noisy than a large diaphragm
capsule on average.

-Todd

That is absolutely FALSE. Selfnoise (all thing being equal) varies indirectly
with the size of the diaphragm. The smaller the diaphragm, the louder the
selfnoise.

Why? Simple physics. The movement of smaller diaphragms produces smaller
voltages differences that those of larger diaphragms.

Sorry.

Ty Ford


Hmm.. yes, in fact I realize I was being quite idiotic when I wrote
that. Apologies all around. Not sure what I was thinking of.

-Todd

Todd Lipcon wrote:


Chel van Gennip wrote:

If you reduce the size of the diaphragms
you have less sound energy, so more noise, mechanical problems etc.

Not true. A small diaphragm capsule is less noisy than a large diaphragm
capsule on average.

You have that exactly backwards. The self noise of the smaller capsule
is greater than the self noise of the larger capsule, assuming all else
being equal.

--
ha

"Todd Lipcon" wrote in message
...
In article ,
Ty Ford wrote:

On Thu, 20 Jan 2005 22:29:30 -0500, Todd Lipcon wrote
(in article ):

In article ,
Chel van Gennip wrote:

If you reduce the size of the diaphragms
you have less sound energy, so more noise, mechanical problems etc.

Not true. A small diaphragm capsule is less noisy than a large
diaphragm
capsule on average.

-Todd

That is absolutely FALSE. Selfnoise (all thing being equal) varies
indirectly
with the size of the diaphragm. The smaller the diaphragm, the louder
the
selfnoise.

Why? Simple physics. The movement of smaller diaphragms produces smaller
voltages differences that those of larger diaphragms.

Hmm.. yes, in fact I realize I was being quite idiotic when I wrote
that. Apologies all around. Not sure what I was thinking of.

What you were probably thinking of is that the noise does get lower when the
diaphragm size goes down, but the signal output gets lower faster, so the
signal-to-noise ratio is what suffers.

Peace,
Paul

The pros here are right of course. Shure has a nice explanation as
well: http://tinyurl.com/3q5nx

I was chasing this a little since I got a pair of Avenson STO-2 omnis.
Very nice mics, BTW.

Steve

It seems the bottom line is

small diaphram = more accurate but worse noise performance
large diaphram = less accurate but better noise performance

Mark

"Mark" wrote:

It seems the bottom line is

small diaphram = more accurate but worse noise performance
large diaphram = less accurate but better noise performance

Mark,

Almost. Try:

small diaphram = more accurate, better off-axis response, but lower output and
worse noise performance

large diaphram = less accurate, poorer off-axis response, but higher output and
better noise performance

This, of course, assumes that everything else is equal which, in real life, it
never is.

Harvey Gerst
Indian Trail Recording Studio
http://www.ITRstudio.com/

Harvey Gerst wrote:
"Mark" wrote:

It seems the bottom line is

small diaphram = more accurate but worse noise performance
large diaphram = less accurate but better noise performance

Mark,

Almost. Try:

small diaphram = more accurate, better off-axis response, but lower
output and
worse noise performance

large diaphram = less accurate, poorer off-axis response, but higher
output and
better noise performance

This, of course, assumes that everything else is equal which, in real
life, it
never is.

Harvey Gerst
Indian Trail Recording Studio
http://www.ITRstudio.com/

Does the noise issue hold true for small dynamics ?
I believe the accuracy, response, and output functions
would equate between condensors and dynamics.

rd