-0 reference ?

[just-some-guy]

ok, trying to learn here.

what exactly does -0 reference mean ? iiuc, its when the volume is all the way up, correct. -0 is all the way up on my receiver. but is there some kind meaning to this in the audio world ?

tia

 

[bandphan]

Reference volume iirc is like 75dbs with peaks to 100dbs.

 

[dem beats]

It means that you are using the amp to it's maximum level suggested. It would be the "referance level" for listening.

Since referance level is what that peice of equipment is intended to produce, it lists it at 0. When you turn the volume down you are brining it further away from it's referance level. So the numers get smaller, which is why you end up in negatives. You are actually attenuating the volume to the level you want.

 

[sptrout]

Below is a link to an article posted on "Secrets of Home Theatre & High Fidelity's" web page about "THX - Certification." Near the bottom of page one, is the description of "reference level".

http://www.hometheaterhifi.com/features/technical-topics/thx-certification.html

In a HT system, reference level is set such that the level of white noise as measured with an SPL Meter, C-weighted, will be 75 dB SPL per channel at the prime listening location. Newer AVR systems, with auto-calibrate capability, will automatically set the levels at 75 dB SPL (among many other things). For older systems, you must do this manually using an AVR's internal test tones, or tones provided by a DVD or CD, and a SPL Meter.

As noted in the article, one seldom listens to a movie at reference level since that is very loud. With my system, I typically listen to movies in the -3 to -5 dB range (as shown on the AVR's display). However, this varies greatly depending on the source and the content. Blu-ray & DVD concerts for example I have run as low as -11 dB and they were still very loud.

 

[fmw]

It has no meaning that I can divine in the consumer audio business. In the pro audio world it normally refers to the clipping point (or, in this day and age, point at which quantization error begins.)

 

[ChrisJam]

ok, trying to learn here.

what exactly does -0 reference mean ? iiuc, its when the volume is all the way up, correct. -0 is all the way up on my receiver. but is there some kind meaning to this in the audio world ?

tia

Volume scales vary according to manufacturer and model. On my old AVR the scale was -100 to 0, IIRC. On my newer AVR made by the same company the scale is -80 to +20.

If I turned the old AVR up to zero, that would be the maximum the amps would play. It'd also hurt the speakers, because there's no extra room for the amp to play dynamic peaks. The amp would clip at those peaks and clipping hurts speakers.

In a -80 to 20 scale, playing sound at zero allows the amp to hold 20 dB in reserve for those dynamic peaks. There's no guarantee this set-up won't clip--some spike might need 30 exta dB--but it's fairly safe.

Some AVRs have user selectable scales, called "relative" and "absolute," IIRC (I never had one of these systems). A user might chose a straightforward 0 to 100 scale, or perhaps the -80 to +20 scale.

Chris