SPL meter ??

[NeilGabriel]

I was looking at articles on SPL meters and one suggested that it was best to get one that gave readings at different frequency levels. If I am only setting channel volumes based upon test tones, do I need something with this ability? Thanks.

[Ricardo]

Not sure I understand this; any SPL meter will give you the Sound Pressure Level of the sound, no matter what the frequency is..... If you want measures at different frequencies, then you get a CD of test tones at different frequencies, and use the same SPL.

Measuring at different frequencies is usually used to test frequency response of speakers/room, blend subwoofers, etc.

For channel calibration, you do not need different frequencies; the test tones of the AVR will be enough (and you can use the Radio Shack SPL meter).

[zingo]

All you need is a basic RS meter like Ricardo suggested. This is the one I have, and the analog meter is great for precise readings.

[jwhitakr]

One point of clarification ... I have always understood that if you are using the analog Radioshack SPL meter, there is a set of corrections that need to be made at certain frequencies. For example, the low frequencies always show up low on the SPL meter and you need to add a few db's to the readings in order to actually have the same SPL across the frequency band.

There are quite a few correction tables on the web and I've read this from a number of people on a number of different forums. I've always used the correction table when I calibrated ...

[shadowofnight]

I have both the analog and digital version of the shack meter....never far :)
In this pic as a matter of fact.....I think what you were referring to was the A and C weighting...not just DB level alone but the frequency spectrum included in the measurment.

[zingo]

Totally. I used the C weighting, and I just worry about main speakers for making sure the volume is equal. I adjust the subs with my ear because I think that is easier then charts and what-not.

[jakelm]

Totally. I used the C weighting, and I just worry about main speakers for making sure the volume is equal. I adjust the subs with my ear because I think that is easier then charts and what-not.

+1

The only thing I found the SPL meter good for in regaurds of subs, is Fr sweeps peaks and nulls and phase callibration, But the ear is used in "blending" the sub with the rest of the system. Although my HK EzEq does a good just at callibration. But I always go back and check.

[ben62670]

I have the Rat Shack digital. I set it to "c weighted" on slow response. It works very well. I like the digital over the analog for the slow response setting, and it is easier to record on paper the readings you get in a sweep. Also check SVS website for calibration on the lower frequencies. Both meters are off up to about 12db at the lower end.

Ben

[zingo]

One of the HT calibration DVDs can really help too.

[ben62670]

Interesting stuff

http://www.svsound.com/questions-faqs.cfm#meter

Calibration table

http://www.svsound.com/questions-faqs-rscomp.cfm

[GV#27]

For the tweakers there is a relatively easy modifcation available for the rat shack meters that give them flat response to 20hz so that correction tables are not needed.If anyone is interested I will dig up the link.I did the mod on my old analog unit and it worked as intended.

[GV#27]

Here is the procedure for the old analog meter. http://mysite.verizon.net/tammie_eri...0/33-2050.html

[ben62670]

Here is the procedure for the old analog meter. http://mysite.verizon.net/tammie_eri...0/33-2050.html

Sweet link.
I still like the SVS correction table. Its easier than modding a stock meter, but if you are into a lot of DIY projects curing the swing at higher frequencies sure would be nice:)

BTW the digital, and analog are only a $5 difference.

[zingo]

Thanks for the link GV#27. I will look into that.

[GV#27]

Sweet link.

There is also mods for 2 other RS units.

I still like the SVS correction table. Its easier than modding a stock meter, but if you are into a lot of DIY projects curing the swing at higher frequencies sure would be nice:)

I like to be able and take a direct reading from the meter and write it down instead of having to add a correction factor.

I use these test tones http://www.realtraps.com/test-cd.htm from the Real Traps site because they are in 1hz steps from 10hz to 300hz.

[ben62670]

I like to be able and take a direct reading from the meter and write it down instead of having to add a correction factor.

Yes tis a mild inconvenience. I use an excel spread sheet to help in that department. I will look into the mod for the digital though. I need better/stable readings in the 2000-3500 range.

Thanks
Ben

[ben62670]

GV you da man!

http://mysite.verizon.net/tammie_eri...5/33-2055.html

Thanks Much. I have to get my read on!
Ben

[GV#27]

I will look into the mod for the digital though. I need better/stable readings in the 2000-3500 range.

Thanks
Ben

I did not do the hi frequency mod on mine yet, but yeh it would be great to have the ability to do accurate measurements when do crossover design.

[GV#27]

Thanks Much.
Ben

Your welcome Ben.

[shadowofnight]

GV you da man!

http://mysite.verizon.net/tammie_eri...5/33-2055.html

Thanks Much. I have to get my read on!
Ben

X2 for GV...I have my analog meter modded but I didnt know you could do the digital version...gonna be done now....thanks :)

[WilliamM2]

If anyone is interested, you can still get the old RS analog meter that the mod article refers to. Cheap too:

http://www.harborfreight.com/cpi/cta...emnumber=92282

[GV#27]

If anyone is interested, you can still get the old RS analog meter that the mod article refers to. Cheap too:

http://www.harborfreight.com/cpi/cta...emnumber=92282

Wow good find.

[NeilGabriel]

These meters say they have various ranges, e.g., 7, is this a setting for distance from source?

[jwhitakr]

These meters say they have various ranges, e.g., 7, is this a setting for distance from source?

No, the analog models have a -10 to +10 range where the little pointer thingie moves back and forth... and then you have to set the SPL meter to the range that you are trying to measure. e.g. set it to '7' to measure from 60-80 dB, set it to '8' to measure 70-90 dB, etc.

[jakelm]

These meters say they have various ranges, e.g., 7, is this a setting for distance from source?

dB ranges, not distance. Like jw said, but I think mine is -10/+6 isnt it?

[jwhitakr]

dB ranges, not distance. Like jw said, but I think mine is -10/+6 isnt it?

Yup, you are right ... it is -10/+6. Leave it to Radioshack to come up with such a nonsensical +/- range. :)