Speaker Workshop + Microphone = invaluable

[Vince35]

5/6

Vincent

 

[Vince35]

The last. (half big)

Vincent

 

[Vince35]

Ok, it works.
Now good luck for the translation !
I (or my father) will try to answer the questions... (if there are)

Vincent

 

[Vince35]

Hello world.

Does my upload work ? It was ok for me, so I need confirmation. If it doesn't work, I'll send the document in email...


Vincent

PS : Chris, fréquentes-tu le forum HC-FR ? ( http://www.homecinema-fr.com/ )

 

[wintermute]

Thanks Vincent,

I picked up the email, so haven't tried downloading the individual files, looks very comprehensive, including amp schematics and all. Now to start on the strategy to get a translation done

Regards,

Tony.

 

[claudio]

internet translation

Hello,
I am interested too in how to measure SPL with SW. So I used Altavista to translate from french into english, just the first part of the article, and here it comes:


""If the tensions of input left and right of the SC are equal, the graphics of the measurement of frequency response show a straight line with 0dB (see further additional checking). It is thus enough to return towards SPK... a reference voltage equal to the output voltage of the microphone obtained for 2,83V at the boundaries of l'enceinte and 90dB to the microphone.

Potentiometer RV1 allows a precision adjustment of the level of exit of the ampli 2,83V (1W/8 ohms). the bridge R3, R4 brings back this level to 0,775V on the left input of the SC (reference). It is thus enough of a micro amplified standard giving 0,775V at exit for 90dB SPL, connected to right input of the SC, to have a graph
calibrated in SPL. 0db on the graph = 90db/1W/1m. ""

So we feed the DUT with 2.83V through the amplifier.
We adjust the SC LEFT INPUT to receive 0.775 V (using 2 resistors).
We adjust the mic preamplifier(right chammel) to read the same value of the left channel in SW VuMeters.
Is it right?

Can someone explain better the relation between 0.775V and microphone standard? The translation is not very good in this point.

Claudio

 

[Vince35]

Re: internet translation

The calibration of our microphone has been made with a reference mic (Brüel & Kjaer) which give 0,775 V for 90 dB SPL.
So when the level is the same on the left and right inputs, and equal to 0,775 V, we have 2,83 V on the DUT and 90 dB on the microphone.


Vincent