Originally Posted by Martycool007
Originally Posted by A9X-308
Yes, because it doesn't give the conditions it was measured under.
Which inuke do you have?
I have no idea what this means. Could I have it in English please?
Yes. Run a test signal through your system at a known level, eg 0dBFS (digital full scale) and measure with a DMM. There are test discs out there that will give you the test signal.
Can a 0dbfs test tone be downloaded? If so, where?
They are all over the web. Either a .wav file or a MP3 file can do the job if you are playing the file on a computer. You can also burn the file to a CD and play that on your BD or CD player. Google is your friend.
You can also roll-your-own with the freeware Audacity audio editor. Then the level and frequency is up to you.
When using a 0dbfs test tone to measure the receivers subwoofer pre-out voltage, what is the proper way to adjust the volume on the receiver so as to get a test tone that is loud enough, but not over 0dbfs?
You want to set the internal channel gains on your receiver for the desired output voltage at the preamp's or AVRs output.
Also, I am assuming that the DMM is a digital multimeter? Can a cheap one from Wal-Mart or Radio Shack work ok for this? What do you set the multimeter to and where should the probes be positioned at for the reading?
Here is what I use for such *adventures*
The Uni-T UT61E DMM shown runs about $60 and has the advantage of having frequency response +/- 0.1 dB over the audio range which cheaper meters don't usually have. In fact its pretty standard for multimeters to cut their response off at a few 100 Hz because they are for measuring power line voltage, eh? You can find lots of retailers on the web that stock the UT61E on eBay, Amazon and the web in general.
As you can see I made my own test cable. I recommend getting a mono dual RCA cable and cutting it in half. Attach a double-banana plug to the cut end. Use this for measuring line level signals. Cut the other RCA plug off of the other one and attach double banana plugs to each end. Use this for measuring the output of power amps and inputs to speakers.
Edited by arnyk - 11/25/13 at 8:05am
I would really like to measure the subwoofer pre-outs on my Denon AVR-3310, just for fun!