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#### waculjr.903

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I hate to ask such a simple question, but what number is actually 50 percent and also full wide open out of curiosity? I usually only bring it up to -20db and the volume is kicking good. I just wanted to really know where fifty percent was, so I definitely wouldn't get into distortion. I am using the Integra 9.8, Emotiva XPA-5 with gains on each channel at -11/-12db. That is what Audessey chose.

#### nova

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Don't think this is so simple a question at all.

The volume knob on a receiver is not a volume control but, in most cases, an attenuator. As I understand it you, are changing the signal prior to the amps where a volume control would change the amplification of the signal. The scale is normally a relative volume scale, say -80dB to +15dB or an absolute scale of 0-100 or something. So you would think that the number that is in the middle of whatever scale is used on your receiver would be 50%, not so.

Throw in the logarithmic scale and things tend to get much more complicated. For example, if you have your receiver set at -30dB and raise it to -29dB you will barely perceive any change. If you raise it to -27dB you'll likely notice a slight increase. When you raise it 10dB to -20dB you will double the volume level and easily hear the difference.

Then whatever gain has been applied to specific channels by Audyssey et al. further complicates things.

So, if my poor explanation is of any help you can see how it is not so simple to find 50%.

Hopefully someone more knowledgeable than I am on this subject will chime in.

#### gregsdouglas

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Nova is right, this isn't a simple question. This was explained to me by an audio engineer and I will repeat the explanation he told me because it made sense - assuming he is accurate!

The issue lies in the difference between perceived volume and actual volume. Our ears are really not that sensitive to changes in volume and it takes a massive change in output to change the perceived volume.

If you look at the voltage going into the receiver's line-in, 0db (or -0db) means the level of voltage going to the amp is equal to the line voltage going into the receiver/pre-amp. At -3db, the voltage is 50% less - so if your Blu-ray player was sending a 1 volt (1000 millivolt) signal out, at 0db, the full 1 volt goes into the amp section. At -3db on a receiver, the amp receives 500 millivolts (mv) and the amp will produce 1/2 the output or 50% less actual volume.

To determine half the "perceived volume," that is going to depend on the efficiency of your speakers and the size of the room. It should be around the 75% mark between full power and zero output.

Sent from my iPhone using HTShack

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