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      01-29-2013, 05:22 PM   #304
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Drives: E92 335D
Join Date: Mar 2012
Location: East Midlands, UK

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Originally Posted by makkan00 View Post
I guess somebody has given you wrong information or somebody at some stage has perceived it wrong.

Drivers (speakers) are being driven by AC current. So, IMHO, with voltmeter you will be checking the AC current and not frquency of sound.
If you do not get AC current at 1Khz, then simply amp is not abled to produced those signals or xovers are not set in that range.

Type of voltmeter becomes irrelevant here as far as it can measure AC voltage within the abilities of drivers / amps range (Lets say upto 20V for 100W driver with 4 ohm amp).

If I am wrong, please correct me.
Yes you will be measuring AC voltage and not the frequency. Think you misunderstood me as i said you'll need a multimeter that can measure ac voltage at 1khz. My point was that the multimeter needs 1khz in its range, i.e able to measure ac voltage at that frequency. Let me explain.

AC voltage is voltage going from positive to negative, i.e alternating current. So it will have a frequency. This is how the frequency of a test tone is reproduced in the driver:
Higher the frequency of the test tone --> the faster the voltage will change from positive to negative at amp output--> faster the driver cone will alternate --> higher audible frequency produced.

Some multimeters can not measure really fast changing voltage, such as 1khz. So you need one that is able to.

Hope thats clearer now.
E92 335D
422bhp 618ft.lbs
Ohlins R&T with custom Swift rears, diff lock plate, monroe upper shock mounts