Help on using a SPL meter...

[Johnny Canuck]

Can someone please direct me to a link or give simple instructions on how to use a SPL meter. i borrowed one from a friend...at least i think it is a SPL meter..it's a Realistic Sound Level Meter,Cat. No. 42-3019. My friend does not have the Avia disc or the like....says to use test tone/pink noise on the Denon 3805...or a THX DVD with set up...

I am having troubles matching the new Hsu STF 3 with my system. Will this SPL be better than the Denon auto set up mic? When I tried the Denon auto set up i got an error message "mic overload". so i turned down the sub...then i got -6.5 for the sub and +12 with my fronts and rears. sub and fronts are 7.3 feet from listening position. i know. don't laugh.

thanks again!!

JC

 

[nibhaz]

I guess the first question I have is: at what level do you have volume/level knob set on your sub? The reason I ask is because my B&W sub which not in the as powerful as your HSU needs the volume knob turned down to just below the 9 o'clock postion, and then it's trimed down -11db in my receiver. I guess what I'm trying to say is if you haven't turned down the volume knob on the sub amp do that first then start over. I'm not sure whatelse you need to know?

 

[Johnny Canuck]

somebody else told me to set my sub volume on my receiver to "0" and dial the sub in with its volume control.

so looking at this meter...it has a dial for range with numbers 70, 80 90 etc to 120...two switches, one for weighting with options A or C, and another switch for response with options slow or fast....then the decibel level meter, -10 to +6.

I have never done this before. Please help from the beginning. I use my Denon test tones and measure each speaker but what am i measuring? where should the settings be?

 

[nibhaz]

Decide if you want to calibrate your system to at 75db or 85db. Take your pick...I prefer to work at 85db, but perhaps someone else around here could make an argument for one or the other that I'm not aware of. If you have an analog meter and you choose 75db set the range dial to 80, if you choose 85db set it to 90. If you’re using a digital you can just set it to 80 for either one. You want the weight to be set to C; this tells the meter to measure a broader portion of frequency range, especially in the lower end. Set the response to slow, this allows for easier reading while taking your readings.

Now for actual use....I like my L\R to be the starting point for the rest of the system. I set the meter up in the listening position, start the test tone on the left and adjust the volume until I get an avg reading of 85db. From here on out I don't touch the volume. As you bring the test tone to each speaker make the necessary adjustments +/- db in the receiver until you get a consistent level across all speakers. I did my sub last, since I figured it would require the most tinkering and since it also has volume knob of it's own it gives you the broadest range of adjustment. This is the basics to my knowledge. Hope this helps.

 

[nibhaz]

one more thing...

One more thing...

I started with my sub's volume knob set a tad under 9 o'clock, for my initial test. My receiver allows me trim down a channel -12db. Since I only had to go to -11db to get my sub-level to match I didn't bother to touch my sub volume again. If I had ran out of room on the receiver's adjustments then I would have turned the sub's knob down...but only in baby steps...until the receiver was able to handle making the correction. This might take several tries if you run in to this situation...basically trial and error. Good luck, ask if you have anymore questions.

 

[Johnny Canuck]

nibhaz....thanks man....i will try this tonight..

I have one more question though regarding subwoofer settings....sub settings for ext. input, where should that be set at? my settings are +15, +10, +5 or 0. right now it's at +10. DVD audio discs pound really heavy in the bass, dvd player set on small speakers.

then there is LFE for DTS movies....where should that be set?

I have noticed that the system sounds better with my Denon EQ set on "manual" and have adjusted my manual EQ settings to make my mid range (250 hz) louder...around +3. 100% improvement!

I also notice that my system sounds much different when you change sources. If I am listening to satellite radio,I have to crank my sub...DVD audio, turn it down...cd's all sound different...will I always have to adjust my settings, once I calibrate, depending on the source?

Geesh...whatever happened to just pushing play??????

 

[nibhaz]

nibhaz....thanks man....i will try this tonight..

I have one more question though regarding subwoofer settings....sub settings for ext. input, where should that be set at? my settings are +15, +10, +5 or 0. right now it's at +10. DVD audio discs pound really heavy in the bass, dvd player set on small speakers.

then there is LFE for DTS movies....where should that be set?

I'm not familiar with the setting you are referring to, or to what its exact function may be. I could guess, but I don’t want you making any adjustments based on my speculation. However when calibrating I believe it's a general practice to have tone controls and such at 0. By doing so it gives you a baseline that's repeatable and a starting point to make adjustments from.

If you watch DTS movies and you want more bass turn up the db if you’re happy with way they sound after you calibrate, leave it alone....what ever sounds best to you. Do to people's differing equipment and room acoustics there is never just one setting that's right for everyone. In cooking they say season to taste...in audio it's adjust to taste.

 

[Johnny Canuck]

I bought the Digital Video Essentials dvd as the Avia is nowhere to be found.....hop it will work..i have read it is similar..

so how does one use this dvd with a SPL meter? Will the dvd guide me?

 

[krzywica]

I have the Avia, and if they are similar at all it will tell you all you need to know, and then some.

About the different levels of playback this is very common and I wish there were more conponents out there to aid in this problem but I am not aware of any (other than car audio). It would be nice to be able to adjust the input level for each source on the reciever, instead of having to adjust it manually. The only remedy I have found is to use macro's on my remote when switching sources. But of course this is not perfect either.

Oh well, some time in the near future I'm sure we will take another big leap in technology and our lives will become that much easier.

 

[warnerwh]

A very important point: When using the Radio Shack meter you need to use correction values as you can't go by the meter. Here they are:

10hz........+20db
12.5hz.....+16.5db
16hz........+11.5db
20hz........+7.5db
25hz........+5db
31.5hz.....+3db
40hz........+2.5db
50hz........+1.5db
63hz........+1.5db
80hz........+1.5db
100hz......+2db
125hz......+.5db
160hz......-.5db
200hz......-.5db
250hz......+.5db
315hz......-.5db
400hz......0db
500hz......-.5db
630hz......0db
800hz......0db
1k...........0db
1.25k......0db
1.6k........-.5db
2k...........-1.5db
2.5k........-1.5db
3.15k......-1.5db
4k...........-2db
5k...........-2db
6.3k........-2db
8k...........-2db
10k.........-1db
12.5k......+.5db
16k.........0db
20k.........+1db

 

[Johnny Canuck]

correction values?!?!??!?!

now I am confused...what and where do I add these amounts to?

 

[warnerwh]

You add or subtract the amount given in the table at each of those frequencies. You can also buy a cd from rives audio that has the correction for the RS meter. It's pretty easy, I don't know what you don't understand.

 

[The Nerdly Guy]

Johnny,

I found a good, a simple to understand, article at my new fav site (url removed) that explains the SPL meter, and how to use it. Here's a link to the article: url removed

PS. Edit: I am a moron who likes to go on forums and do nothing but self-promote myself.