If I want to test a room or, say, my card for audio neviroment (how
loud, possibly some frequency info) what's the best way to go about
it?

For the room, I can use several microphones and a good sound card
I have in a PC. What's the best procedure?

For the car, anyone know of good, cheap hand held devices?

Thanks in advance.

i've used this device before. works well i think...

http://www.radioshack.com/product.as...t%5Fid=33-4050



Philip N. Daly wrote:
If I want to test a room or, say, my card for audio neviroment (how
loud, possibly some frequency info) what's the best way to go about
it?

For the room, I can use several microphones and a good sound card
I have in a PC. What's the best procedure?

For the car, anyone know of good, cheap hand held devices?

Thanks in advance.

"H" wrote in message
news:3V1_d.57613$i6.37050@edtnps90...
i've used this device before. works well i think...


http://www.radioshack.com/product.as...t%5Fid=33-4050

I have a digital version which has a similar range, and can store max and
min, and has a choice of weightings. No idea of the accuracy. Our
professional meter at work came with a calibrator.

--
M Stewart
Milton Keynes, UK
http://www.megalith.freeserve.co.uk/oddimage.htm

On Wed, 16 Mar 2005 21:53:03 +0000, H wrote:

i've used this device before. works well i think...

http://www.radioshack.com/product.as...t%5Fid=33-4050

I'm interested in making some rudimentary measurements in my studio as
well.

What would be the basic procedure?
Here is what I have in mind.

1. Position meter at sweet spot for listening (or about 1 ft in front of
each monitor if measuring monitor response).

2 . Play a series of tones, say 40hz, 100hz etc.

3. Write down the levels from the meter.

4. Graph it.

Would this basic approach, crude as it is, work?

Steve

Steve Glenn wrote:
On Wed, 16 Mar 2005 21:53:03 +0000, H wrote:


i've used this device before. works well i think...

http://www.radioshack.com/product.as...t%5Fid=33-4050


I'm interested in making some rudimentary measurements in my studio as
well.

What would be the basic procedure?
Here is what I have in mind.

1. Position meter at sweet spot for listening (or about 1 ft in front of
each monitor if measuring monitor response).

2 . Play a series of tones, say 40hz, 100hz etc.

3. Write down the levels from the meter.

4. Graph it.

Would this basic approach, crude as it is, work?

Steve

Basically, yes, but you'd need wider frequency response than that.
The A above middle C is 440 Hz so on an 8-octave keyboard the range
would be 28 - 7040 Hz! Would also consider measuring volume in the
range 40 - 110 dB.

Comments? Brickbats and bouquets!

P

In article , Philip N. Daly wrote:
If I want to test a room or, say, my card for audio neviroment (how
loud, possibly some frequency info) what's the best way to go about
it?

What do you want to test it for?

For the room, I can use several microphones and a good sound card
I have in a PC. What's the best procedure?

Depends on what you're testing. You want to know RT60 or decay spectrum,
that's a different thing than knowing room response of a speaker system in
a small room. What do you want to measure?

For the car, anyone know of good, cheap hand held devices?

To measure what? If you just want to know absolute level with A or C
weighting, the cheap Radio Shack meter (don't buy the digital one) is
surprisingly accurate. But it won't measure down to very low levels and
it won't do anything with more low end extension than C weighting.

I'm not sure if knowing absolute level really tells you anything much useful,
though.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Malcolm Stewart wrote:
"H" wrote in message
news:3V1_d.57613$i6.37050@edtnps90...
i've used this device before. works well i think...

http://www.radioshack.com/product.as...t%5Fid=33-4050

I have a digital version which has a similar range, and can store max and
min, and has a choice of weightings. No idea of the accuracy. Our
professional meter at work came with a calibrator.

The digital Radio Shack unit is unusable because the numbers jump around too
quickly to be useful, and there's no way to see trends. The cheaper one is
much more useful and a test unit agreed with my NBS-traceable GenRad within
2 dB from 20-20 KHz on A-weighting. It ain't no B&K, but for the price it is
not half bad.
--scott


--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Steve Glenn wrote:
I'm interested in making some rudimentary measurements in my studio as
well.

What would be the basic procedure?
Here is what I have in mind.

1. Position meter at sweet spot for listening (or about 1 ft in front of
each monitor if measuring monitor response).

2 . Play a series of tones, say 40hz, 100hz etc.

3. Write down the levels from the meter.

4. Graph it.

Would this basic approach, crude as it is, work?

No, because unless a room mode is directly on one of the tones you are playing,
you won't notice it.

A warble tone set is more useful than the tone ladder for this reason, but it
will still miss narrow resonances.

Sweeping a tone back and forth by hand and looking at the meter (and also
listening) is much more useful. Of course, you still have to do it at a
dozen or so points in the room.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

1. Position meter at sweet spot for listening (or about 1 ft in front of
each monitor if measuring monitor response).

2 . Play a series of tones, say 40hz, 100hz etc.

3. Write down the levels from the meter.

4. Graph it.

Would this basic approach, crude as it is, work?

Steve

Basically, yes, but you'd need wider frequency response than that.
The A above middle C is 440 Hz so on an 8-octave keyboard the range
would be 28 - 7040 Hz! Would also consider measuring volume in the
range 40 - 110 dB.

Comments? Brickbats and bouquets!

Why not use white noise and a FFT analyzer? Using a good front end, like the
MOTU 896, and SoundForge with the Spectral Analysis plugin is a good way to
do it. Record ten seconds of white noise played on the speaker under test,
using a mic with a known response (preferably flat). Select the recorded
segment, run the FFT plugin and set the graph options for the highest FFT
resolution and the range to that which you're interested in.
Works well for me.

BTW, speaking of sound level meters, does anyone make a portable meter that
is accurate to slightly beyond 150dB and down to 16Hz?


--
Best Regards,

Mark A. Weiss, P.E.
www.mwcomms.com
-

Mark & Mary Ann Weiss wrote:

Why not use white noise and a FFT analyzer? Using a good front end, like the
MOTU 896, and SoundForge with the Spectral Analysis plugin is a good way to
do it. Record ten seconds of white noise played on the speaker under test,
using a mic with a known response (preferably flat). Select the recorded
segment, run the FFT plugin and set the graph options for the highest FFT
resolution and the range to that which you're interested in.
Works well for me.

Takes more than ten seconds if you care about low end, but if you are going
to go that route, you might as well just do MLSSA-style impulse responses
and be done with it.

BTW, speaking of sound level meters, does anyone make a portable meter that
is accurate to slightly beyond 150dB and down to 16Hz?

B&K, Ono Sokki, and Larson-Davis. Ivie probably does too. Note that the
accompanying mike will cost more than the meter.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Philip N. Daly wrote:
If I want to test a room or, say, my card for audio neviroment (how
loud, possibly some frequency info) what's the best way to go about
it?

For the room, I can use several microphones and a good sound card
I have in a PC. What's the best procedure?

For the car, anyone know of good, cheap hand held devices?

Has anyone use the "Sound Check 2" CD with response analyser? for
testing room/monitor responses?
http://www.interstudio.co.uk/sndchk.htm

I'd be interested to know how this compares with fancy test equipment -
Sound Check is produced by engineers with a very respectable background,
so it ought to be useful.

(the relevant parts are a series of band limited pink noise samples on
the CD, combined with a mic + LED level meter apparently built into the
CD's jewel case.)

I've just finished building/treating a room and want to see how well
I've done/assess monitor reponse tweaking requirements.

Anahata