Arta

[Safos]

Which calibration file do you use guy for capsule Panasonic MW61A?
Do you recommned any other microfone which is better that "home made" pipe with MW61 but relatively not very expensive?

Safos,

[Loren42]

ECM8000

[ente]

Hi,

ARTA 1.7.1 is available on the ARTA homepage (just a service release). (ARTA Download)

Furthermore there is a interesting tool for guys who are performing a lot of polar measurements. It's just a little AutoIT macro, but it makes repetitive measurements much more handier. Thanks to Fabian.

(http://www.fesb.hr/~mateljan/arta/Ap...%20EngRev1.pdf)

Comments and wishes are welcome!

Regards
Heinrich

[Jmmlc]

Originally Posted by Safos

Which calibration file do you use guy for capsule Panasonic MW61A?
Do you recommned any other microfone which is better that "home made" pipe with MW61 but relatively not very expensive?

Safos,

Hello,

For what it's worth, you may find here attached a calibration file that should be convenient for many cheap electrets capsules.

You'll have to change the extension .txt by an extension .mic before to import it inside ARTA.

BTW : for the French reading people I begun to write several threads about the practical use of ARTA on the french forum of the association "Mélaudia".

See :

MELAUDIA :: forums - mesures


Best regards from Paris, France

Jean-Michel Le Cléac'h

[rich08]

Hello Ente. I was thinking about smoothing distortion in Step. I think it would in some ways more transparent result. Farina system can be smoothed out, and would help in Step ...
It might be interesting to increase sequence lenght on 512k or 1024.

Richard

[rich08]

Hello Ente, another idea is 5th and 6th harmonics or next in Farina system...

[epa]

can anyone tel me wats wrong with my setup.
overlay is left channel input,green right
ive used both the onboard audio and an usb audio device.
ive made the setup with 8k2 ohm and the 910 ohm resistors with the zenerdiodes.
and 28 ohm(2x56ohm paralel)
also used 2 different amps.

its an 8 ohm speaker so the value seems to be ok,but the second impedance peak is negetive .green trace
any help would be greatly apreciated.

[epa]

to be clear
green is refernce channel left,and yellow is refference channel right.

[DBMandrake]

Your mains electricity is at 50Hz ? (I'm assuming so in amsterdam) It will be some sort of earth loop hum pickup issue.

Are you driving the speaker directly from the sound card via a resistor (in the 33 - 100 ohm range) or via an external power amp ?

By the way, the shape of the main impedance peak is all wrong, (it should be a symmetrical bell curve) so even besides the anomaly at 50Hz there is something very wrong with the measurement setup.

[DBMandrake]

Sorry I just noticed you said you're using an external amp, so earth loop issues most likely are your problem or at least part of it.

If your sound card can drive 33 ohms (most can as thats standard headphone impedance) then simply drive the speaker direct from the sound card via a 33 ohm resistor, (or 68 ohms if your card struggles with 33) with your line input left connected directly to the sound card output and line input right connected to the junction between the resistor and speaker.

Both line inputs should have zener diode protection as shown in the arta docs.

T/S measurements should be done at quite low voltages anyway, so the direct output from the sound card is sufficient, and performing the test at higher cone excursions will introduce inaccuracies.