Receiver volume (dB) ?

[The Big Blue]

At the risk of sounding like an idiot....

My new receiver is the first I've owned to have the volume readout on the display in dB. Could some kind soul give me an idea what this all means? e.g. what does 0dB represent? etc....

[Bourne1]

It just means decibles. It's a measure for sound level. I believe 0db would represent your highest volume level or no change in sound leve. I am not 100% sure.

[MacDaddyOJack]

It can depend on your reciever and your setting. Onkyo has an absolute and a relative volume (measured in dB). In relative, the zero setting would be considered the 'reference' volume. In absolute, the zero setting would mean that you have it turned all the way up. And that is just with Onkyo! It is really just a number, find out what volume you like it at and then use that as a basis to set for when you start a movie.

[WriteSimply]

0 dB means audio at Reference Level. As in, the level of audio you would've heard if you were in a theater. Not recommended if you have thin walls and neighbors, since it is very loud. And if your speakers are not up to snuff, it can damage your speakers too, as well as create a power outage since you suck up a lot of electricity.

The simple guide is play as loud as you can at reasonable hours without the neighbors/wife coming at you with a loaded shotgun.


fuad

[The Big Blue]

So 0 dB should be reference level (85 dB? I remeber back in the day there was some confusion from somewhere as to whether it was 75 or 85)

My new receiver is a Sony 3300ES btw. I've barely been able to play with it yet and haven't even cranked anything up yet. That will be corrected tonight.

[MouseRider]

Originally Posted by The Big Blue

So 0 dB should be reference level (85 dB? I remeber back in the day there was some confusion from somewhere as to whether it was 75 or 85)

My new receiver is a Sony 3300ES btw. I've barely been able to play with it yet and haven't even cranked anything up yet. That will be corrected tonight.

Reference level for home theater as per THX and convention is 105dB peak SPL (Sound Pressure Level).

When you perform manual calibration, to make it bearable for you to be in the room, most calibration white noise segments are recorded with a -20dB or -30dB attenuation which means you calibrate with your SPL meter at either 85dB or 75dB respectively.

The volume indicators on receivers and pre/pros that show dB is basically showing you the level of attenuation, not the volume level.

So at 0dB, if correctly calibrated, your speakers should be pushing out at 105db if they are receiving peak volume, which almost never happens.

Not many systems can really adequately perform at reference levels, but many homes don't need systems to perform at reference levels.

[crackinhedz]

Originally Posted by WriteSimply

0 dB means audio at Reference Level.

god I love learning something new! I can get to about -4 and I have to stop! (scared to go any further) never new why though. thanks.

another question I never really comprehended is why does it go (well at least my receiver) from the high negatives (low volume) down to zero (high volume)?

[crackinhedz]

Originally Posted by MouseRider

The volume indicators on receivers and pre/pros that show dB is basically showing you the level of attenuation, not the volume level.

missed it the first read through. Excellent thanks.

(makes all the sense in the world now)

[MouseRider]

Another fact to remember is that decibels (dB) is logarithmic scale and not linear.

[saprano]

Originally Posted by crackinhedz

god I love learning something new! I can get to about -4 and I have to stop! (scared to go any further) never new why though. thanks.

another question I never really comprehended is why does it go (well at least my receiver) from the high negatives (low volume) down to zero (high volume)?

-4? i can only go as high as -13, any louder and im trouble, looks like i need to do more tweaking

[Sylin]

Originally Posted by The Big Blue

what does 0dB represent?

0dB stands for Old Dirty Bastard, and he represents Compton, yo. Wu Tang 4-eva.

/ghetto

[Merrick]

There is no such thing as "absolute" dB. By definition dB is a relative scale. That having been said, dB could easily be used *mistakenly* as an absolute measure, and is often used (though, really, incorrectly) in the place of dB(SPL).

And it's decibel (as in 1/10 Bel) and not decible. In our case we are concerned about acoustic decibels - though there are power, voltage, bandwidth, etc. usages.

The reference [i.e., 0 dB(SPL)] pressure for dB(SPL) is 20 micropascal - the quietest sound a typical human ear can hear. Any other definition of 0 dB is purely relative.

[The Big Blue]

Crap! Just when I thought I was starting to understand.

[MacDaddyOJack]

Originally Posted by The Big Blue

Crap! Just when I thought I was starting to understand.

He is just saying that there is more than one decibel scale. For the purposes of home theater, we are only concerned with the decibel that measures SPL, or Sound Pressure Level. Again, the 0dB setting is the reference setting and is generally defined as 105dB max output, pretty loud I know my theater can handle it with very little distortion, but its freakin' loud! I usually watch at about -10 or so depending on the movie.

[saprano]

so whats the +db on the onkyo's? my audyessy set my speaker db's in the negatives, so on my reciever the lower the number the louder it gets, i dont think i can get pass -10db. so are the positives louder or somthing?.

[Automission]

sorry to bump, but what exactly is the deal with a low number being louder? I ran my auto setup and my speakers set the db to -7, -10, etc. now at that, I need to turn my volume dial to 40+ to hear things, while if I set them to +7 +9, etc, It is much easier to reach a more audible level earlier, i.e Volume level 22.

Is this harmful, or is it just a case of choosing what the default volume level is at?

[DonRSD]

Originally Posted by Automission

sorry to bump, but what exactly is the deal with a low number being louder? I ran my auto setup and my speakers set the db to -7, -10, etc. now at that, I need to turn my volume dial to 40+ to hear things, while if I set them to +7 +9, etc, It is much easier to reach a more audible level earlier, i.e Volume level 22.

Is this harmful, or is it just a case of choosing what the default volume level is at?

instead of 'reference level' being 0db....youve raised it
so now 'reference level' may be -20db....depending on how much you raised the speakers up in volume

[BIslander]

Originally Posted by saprano

so whats the +db on the onkyo's? my audyessy set my speaker db's in the negatives, so on my reciever the lower the number the louder it gets, i dont think i can get pass -10db. so are the positives louder or somthing?.

0 db is usually the reference level - much louder than you would want to listen to for any length of time. If you calibrate with an SPL meter to 85db and the AVR dial set at 0, you'll get peaks up to 105db. But, after calibration, you'll probably end up doing playback at -20 to -30, depending on the volume of the source recording. So, you'll be listening at 55-65db with peaks of 75-85db.

[Rob J in WNY]

Basically, 0dB means you have your volume set at its maximum, often referred to as "reference volume." Turning the volume down from 0dB is what gives you values such as, for example, -20.5dB. All this means that you are listening at a level 20.5dB quieter than the maximum amplifier volume.

Now, having said that, what you actually hear at a given volume setting is a relative thing entirely. Different input sources and program volumes, played back at an identical volume setting, will vary in perceived loudness.

For example, a CD played back at a -20.5dB volume setting may sound noticeably louder or quieter than a different CD played back at -20.5dB, or a DVD or BD played back at -20.5dB. Some aspects of audio levels are standardized (such as the attempt to use "Dialnorm" on BD discs - another subject entirely), but there is still a lot of variation from source to source.

Your receiver only serves to amplify what is presented to it. Thus, a volume value of -20.5dB will offer your ears different sound levels for different program material, but it is accurate to say that, based on the 0dB "reference" level, what you are hearing is -20.5dB quieter than the same program material played at 0dB.

The use of a decibel scale to show you your volume setting is simply a more accurate and technical way than, say, the classic "1 to 10" scale. Other receivers may show percentage values, such a 0% (muted) to 100% (reference volume).

When considering the decibel scale in your volume setting, note that for every 3dB increase you make in volume, your amplifer will attempt to double its power output. Now, 3dB is not a fantastic increase to your ears, but asks a lot of your amplifier if you are playing closer to reference levels (in other words, really loudly already). By that measure, a 6dB volume gain will four-fold the amplifer power increase, and a 9dB gain will create an amplifer increase of eight times the power. Hence, as MouseRider previously posted, the decibel scale is not a linear scale.

I would not recommend trying to run your receiver at 0dB for any length of time. Because differing program material will have different recorded levels, some program material is low enough to avoid over-driving your amplifier (clipping), while others will easily push your amplifier beyond clipping at 0dB. You have to know your equipment limits. Clipping can damage the amplifer and your speakers. The loudness levels incurred at 0dB is not good for your ears, either. Reference volumes are fun to demonstrate on occasion, but are debilitating to your ears over time.

[d.white]

ODB is from New York FYI.