spl meter

[d.white]

having trouble using radio shack spl meter, what is the volume level suppose to be at before you run the pink noise through each channel,i read big daddys sticky,but i dont remember seeing that,on my third beer and a pint of brandy might not be helping the situation any,any help would be appreciated.

[crazyBLUE]

Originally Posted by d.white

having trouble using radio shack spl meter, what is the volume level suppose to be at before you run the pink noise through each channel,i read big daddys sticky,but i dont remember seeing that,on my third beer and a pint of brandy might not be helping the situation any,any help would be appreciated.

Maybe wait until tomorrow to do it & Just enjoy it tonight

[Big Daddy]

Originally Posted by d.white

having trouble using radio shack spl meter, what is the volume level suppose to be at before you run the pink noise through each channel,i read big daddys sticky,but i dont remember seeing that,on my third beer and a pint of brandy might not be helping the situation any,any help would be appreciated.

Blame it on poor Big Daddy. You really need to calibrate your audio while you are sober.

This is from Big Daddy's sticky thread on Calibrating Your Audio with an SPL Meter

Reference Level
Reference level is defined for film mixing and movie theaters. Every studio and movie theater is calibrated according to this level. It represents an average of 85dB for the regular speakers on the SPL meter (set on C weighting and Slow) using a band limited (500Hz to 2,000Hz) pink noise at the listening position. The peak level is set 20dB higher at 105db and the LFE peak level is set +10dB higher to a maximum of 115dB. The purpose of the +10 dB gain for the LFE channel is to increase the dynamic range of bass sound such as explosions and crashes. This means when the receiver's master volume is set to 0dB, the regular speakers are expected to play a peak level of 105dB and the subwoofer is expected to produce a peak output level of 115dB. This is louder than most people can tolerate, so people normally set the master volume much lower than 0 when watching movies or listening to music. Furthermore, such loud bass level places a heavy burden on the subwoofer and requires multiple high-end subwoofers to produce it accurately.

Because 85dBC test tones can be very loud in a small home theater room and can damage hearing, receiver manufacturers through the encouragement by Dolby and THX decided that a reasonable test-tone level is 75dB and that is the level that most receivers use.


Measuring and Evaluating the Response
When you go into the receiver's manual setup mode and play test tones, the master volume on some receivers will be disabled and the test tones are played at 75dBC reference level for home theater. You can use the gain level for each speaker inside the menu and adjust their levels so that you get 75dB on the SPL meter. It is ok to adjust them a little higher in order to get 78dB or 80dB.

The master volume is not disabled on some receivers when you go to the manual setup menu. For these receivers, you can choose either the left front channel or the center channel and adjust the master volume until you read 75dB on the SPL meter (+5dB on the analog meter), or the level that the calibration disc specifies. Once you have completed this step, do not change the master volume.

As the test tones go through each speaker, use the adjustment level for that speaker (not the master volume) to cut or boost the output for that speaker to 75db. When you are finished, every speaker should output the same volume level to your listening position. Your subwoofer should also be adjusted to the same level, but if you like a little extra bass, calibrate it 5db more than the other speakers.

[d.white]

Im good now, thanks B.D.

[tlinnert]

Hi, I recently noticed that my movie dialog is drown out by volume of other speakers, particularly during action/explosions, etc. Before I use my Radio Shack analog SPL, I wanted to confirm whether:

1.) the receiver volume is important to the test? For example, before playing any of the pink noise test tones, what base volume should I be turning my Onkyo 606 AVR up to? If I set the Onkyo volume to like ~40, it seems I have to turn the speaker levels up to ~+10 db per speaker just to register +5 db on the SPL (set at 70) = 75db. But if I crank the receiver volume up, it doesn't require as significant of per speaker sound level adjustments.

2.) after I effectively correct the speakers so their volumes are balanced, wouldn't I still want to increase the db volume of the center speaker to compensate for low dialog? what do you all suggest?

Just want to ensure I'm doing it correctly. Any advice would be much appreciated. Thanks.