Reference listening level??

[eapiel]

What exactly is this supposed be? I have searched the web and this site looking for a definition to no avail. My Onkyo receiver has this setting in the volume display which is LOUD when I set it that high.

Is this supposed to be some standard for listening levels for a pre-defined environment, or another marketing scam? Just curious.

[dougdrake]

Depends on the context it is in, I believe. If you are referring to Home Theater, it means setting the volume at a level which will enable the system to reproduce the volumes to the maximum level dictated by the audio format in use.

For example, Dolby Digital specifies 105db as the maximum (with 115db, I believe, for the subwoofer). Thus, many calibration disks have their test tones recorded at 75db or 85db (30 or 20 db "down" is what it's referred to as) so that when you calibrate you don't melt your ears. Make a note of what setting your receiver/preamp was at when it achieved that volume (using an SPL meter to measure the volume in your seating position). Then, whenever you return the receiver to that position when watching a DD DVD, you know your system will be able (if it has the power to, anyway) to hit reference levels as they were intended to be heard.

The reference markings on preamps/receivers (such as 00 on the volume setting on my Denon) are meaningless in your system, due to the varying sensitivity of your speakers, your room arrangement, and so forth. That's why you need an SPL meter to accurately know where "reference" is in your system. If I set my Denon to 00 ("reference"), I'd be about 20db OVER reference volumes, and in search of an ear doctor.

DD

[eapiel]

Thanks for the response, RS SPL meter is on the top of my shopping list. How many db's would I be looking for a home theater "reference level". I realize this may be an ambiguous question as I will use the SPL to balance my system but I am again curious regarding the intended db level by the film's producers.

For that matter, does anyone know the db intended levels of 2 channel stereo music? By intended I mean the sound level as mixed by the producers of the music tracks when they produce the original cd or digital track.

Thanks.

[HornEd]

Reference level can be confusing... especially since it changes from one authority to another. The Dolby Digital Reference Level for Home Theaters is 85 dB for the front and rear array speakers and 115 dB for subwoofers (LFE). The Dolby Digital Reference Level for Professional Theaters is higher, 121.5 dB at 20 Hz.

Reference level for your basic surround system is set by using an SPL (Sound Pressure Level or volume) meter. I prefer to set my speakers up at 75 dB... as the 85 dB standard gets VERY loud... going up to as much as 105 dB for extended periods. Thus, you calibrate all of your speakers (except subwoofers) to a test tone (like pink noise) to 75 dB... that balances the sound from all speakers. In essence, it creates a level playing field by which you can better appreciate how the sound mixer has prepared a

DVD move or CD music experience for you. Subwoofers are set louder because, realistically, sounds recorded in the Dolby Digital format can be very lound... but usually less then a second at the highest levels. This brief spike is thought not to be a threat to your hearing and contributes a high degree of realism to movie sound such as crashes, explosions, and the thunderous applause has fini presents his nude avatar.

It is important to use an SPL meter and a set-up disk (i.e., Avia) to set up your speakers reference levels. A Radio Shack SPL meter can be had for under $50 and will do most set-ups quite nicely. Be sure to get the analog model for it is more accurate for this particular purpose... and cheaper too! It is physically impossible for the human ear to correctly set-up speakers... because of the persistance of sound dynamic that affects every ear... just like persistance of vision makes it possible to "see" a movie that is really a series of still pictures.

So, when you set up your system to a reference level you are integrating all speakers properly and leaving enough room for the sound mixer to deliver a full spectrum of sound from low lows to high highs... within the Dolby Digital recording parameters. Any system will sound MUCH better when properly set up. Do it right and enjoy! =HornEd

[prodj101]

my rs spl meter was only like 15 bucks. the digital ones seem like they'd be really hard to use for measuring spl, especially peaks.