spl meter help

pmckeealaska

I just picked up an SPL meter to calibrate my HT setup and will be using my revievers test tones to calibrate my system. Does anyone know of any good links that can give directions on how to use the SPL meter? Thanks!

shawn474

Here's the link:

http://www.audiophilia.com/hardware/spl.htm

pmckeealaska

Great! Thanks a lot!!

aaharvel

use the C weighting on "Slow"
stand BEHIND your listening position and hold the SPL meter out to where your head would be, and make sure it's pointing upwards toward the ceiling. NOT towards the front.

MrNightly

So I need a CD as well to calibrate huh? Now I find that out. Arg. Can't you use the built in tones of the receiver??

mldennison

well you dont "need" to have a CD/DVD to do it. you definately can do it with the tones in the receiver. the idea behind using a CD/DVD is that there might be something in the signal path between your source and receiver that alters the sound somewhat and since you will always be listening off of your source, you measurements could be a little off.

i have tried both in the different rooms that i have setup my system in and have never noticed a difference of more than 1dB between the two.

MrNightly

Cool. I'll try using the tones in the receiver first (These are the ones from the receiver where we select the level for each individual speaker right?). Did you find it very difficult to set properly? The page listed above didn't seem to easy. Just wondering!

Thanks

mldennison

yeah, you want to play the tones for all of the speakers and then adjust so that they match. give it a few seconds at each speaker to make sure the level is steady before changing it. also, since the low frequencies are not very directional, you want to "wave around" the meter when you are doing the sub to get a good idea of the sound from all around, not just those coming directly from the sub.

it really is not hard to do and i know i was suprised at the difference between my ears setting the levels and the meter!

MrNightly

Very good. Thank you. My wife is picking up some 9v batteries And then i'll get to work!

Cheerio

Holydoc

mldennison wrote:

well you dont "need" to have a CD/DVD to do it. you definately can do it with the tones in the receiver. the idea behind using a CD/DVD is that there might be something in the signal path between your source and receiver that alters the sound somewhat and since you will always be listening off of your source, you measurements could be a little off.

i have tried both in the different rooms that i have setup my system in and have never noticed a difference of more than 1dB between the two.

With my receiver, I have found just the opposite. The built-in test tones are not even close to running AVIA from my DVD player. And since all my HT experience will be coming from that DVD player, I trust it much more.

MrNightly

Ok, I guess I'm pretty stupid, but how do I change the frequency on my HT with only the SPL meter? That article keeps talking about all that. Also, Am I suppossed to test all speakers at once, or each individual speaker at a time? Sorry for the dumb questions, but its like greek to me.

Holydoc

Your HT system should have a way to adjust the power to each individual speaker. It is usually near or at the same place where you can invoke your internal test tones.

You will be testing each individual speaker. The goal is to get all your speakers, when your receiver volume/gain control is set to the "0" setting, to the same sound level. The sound level that you are trying to achieve is called the standard reference level. This level should be 85db, for each speaker, tested at your listening spot.

This sound level is not the level you have to listen to movies at. For most people this is entirely too loud. However movies are mixed to play best at the reference level so that is why you calibrate at this level. I generally watch movies at a volume/gain setting of "-10" though I am calibrated at "0".

Dennis Gardner

MrNightly wrote:

Ok, I guess I'm pretty stupid, but how do I change the frequency on my HT with only the SPL meter? That article keeps talking about all that. Also, Am I suppossed to test all speakers at once, or each individual speaker at a time? Sorry for the dumb questions, but its like greek to me.

You can't change the frequency. That is why you either need a setup DVD/CD made for testing or tones downloaded and burned onto a disk to test all ranges of frequency.This site has them individually so you can work with subwoofer tones too.

http://www.snapbug.ws/sinewaves/

MrNightly

Ahh, that might explain things Mr Gardner. Thank you. I was scratching my head thinking I didn't have a clue how to change the frequency, but what you said makes sense. Thank you muchly. I'll have to burn a disc and see what happens. Now, with a proper mic hooked into the Denon, and this disc playing the frequencies, I can select the "Auto setup" mode right? and have the receiver calibrated that way right?

At least now all the speakers are at the standard reference level. Making progress Is it normal to run a AVIA like disc to help smooth frequencies or is it even worth it?

Dennis Gardner

The Denon's auto settings can be pretty good if you don't have alot of room anomolies to confuse the setup. It should give you a good baseline to begin. I still suggest getting Avia or Digital Video Essentials since they also have help to calibrate your video (DVDPlayer/Projector/TV) with too.