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HamLet
03-13-2007, 05:41 AM
I asked this in HA, but no one answered ... Better luck here?

Here is the situation: I created a file in audacity via generate -> tone -> 440 Hz, Amplitude 1 at 16bit 44.1 KHz I feed the digital output from my soundcard directly into a Behringer DEQ2496 digital equalizer -- A nice toy that happens to have a digital peak/rms meter (0.1 db accuracy)

The following happens:

1. If I play the file directly from audacity I get peak= 0dB and RMS = -3 dB -- no surprises here.

2. If I save the file as wav and play it in foobar2000 or in WMP I get peak = clip , and -3db RMS

3. If I play the wav file in dBpowerAMP I get peak = -6 dB and RMS = -9 dB.

OK, so what goes on? Clearly the digital output is different in the 3 cases above, but why and how?

It seems that dba chops one bit, true? But why is 1 and 2 different? Is there a simple way to look directly at the samples? Maybe capture on a different PC?

Thanks! -- Ham

LtData
03-13-2007, 11:38 AM
If you play your saved WAV file in Audacity, does it give the same output as before?

Spoon
03-13-2007, 04:56 PM
You have the option of using DirectX out or WaveOut, each of these have different volume defaults.

donny
03-13-2007, 06:49 PM
yes the directx is quieter. I prefer this for two reasons, one if I watch movies the volume level is more similar, two it doesn't touch my "wave" system volume.

it could be the difference.

the other difference could be because of the export function in audicity, maybe... this is just a guess thou.

HamLet
03-14-2007, 01:33 AM
(1) Opening a saved file (vs local generate) (both 16bits, 44.1 ) does not make a difference in Audacity: peak = 0, rms = -3

(2) Changing dba from WaveOut to DirectX does not make a difference either: peak = -6, rms = -9

So let's assume that I record the samples somehow (for instance Audacity in another machine). Is there an easy way to see the actual values of the samples?

Many thanks! -- Ham