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Posted By: BobG Sound Level meter - 01/05/08 04:35 PM
I need information on how to actually use the digital Radio Shack sound level meter to calibrate my system. I have M80's, VP150 and QS8's (no sub) with a Sherwood Newcastle R965. (My receiver is the older version that does not have the auto calibration function. I have the software to update it, but it will be a while before I get motivated to disconnect the receiver and bring it to my computer, and I need to find someone who can show me how to actually do the update, since I am not computer savvy.) Anyway, I know how to get the test tones out of my receiver, and how to adjust the volume for each channel. But, what I need to determine is the actual process for using the sound level meter to calibrate the speakers. If you could direct me to a source for this info, or provide assistance here, that would be much appreciated.

Thnaks in advance.
Posted By: St_PatGuy Re: Sound Level meter - 01/05/08 04:56 PM
Bob, you want to make sure your meter is on "C"weighting and set the response to "slow." Then, simply sit in your normal listening position and hold the meter upright (I try to hold it close to my head to approximate a reading where my ears are). With the receiver's test tone calibrate your left front speaker to 70-75dB (70dB may be easier to read on the meter--turn the big dial to 70 and when the needle is on 0, or right in the middle, you're at 70 dB. Then, play the test tone through the other speakers, matching the same decibel level to the left front. You can tweak a little here and there to suit your tastes. Some set the center channel just a tad higher, but it's all personal preference.
Posted By: SirQuack Re: Sound Level meter - 01/05/08 05:03 PM
I'm finding that not all receivers allow you to do this Sean. On my Denon if I kick off the test tones, the receiver uses a built in pattern and you can't adjust the left speaker like the old days.

Bob, the main thing is that all speakers are showing the same SPL on the meter. I usually use 74dB. So, whether you kick off the receiver automatic built in tones, manually cycle through the receiver tones, or use one of the many calibration cd's, the goal is to get all the speakers/sub to the same spl.
Posted By: BobG Re: Sound Level meter - 01/05/08 05:08 PM
OK, thanks. One more question. Do I turn the meter microphone to face each speaker as I calibrate that speaker, or do I just hold it vertical and leave it in the same position throughout?
Posted By: St_PatGuy Re: Sound Level meter - 01/05/08 05:10 PM
Hold it vertical and in the same position.
Posted By: SirQuack Re: Sound Level meter - 01/05/08 05:13 PM
The instructions should tell you that came with it, however, the microphone is designed to pick up signals from around you. Many people place it in a camera tripod facing up. For me, I usually have it slightlyyyyyy pointed forward towards the front, but not much. If you think of your ears on the side of your head, they are not aiming backward, and are designed to primarly focus to the side and forward. I figure this way, you will bump up the surround levels a bit more for a better experience. \:\)
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