Radio Shack SPL Meter corrections


Looking at some other recent thread and some own experience, I have come to question the accuracy of the Radio Shack SPL meter and some of the suggested (measured?) correction curves. I was wondering what your experiences with the meter are and what correction curves you use.

I found the following different suggestions for correcting the meter readings:

Sean's Audiogon corrections

Audio Asylum corrections

The issue of the SPL meter corrections came up in a recent thread:

4khz-8khz room spike

From my own experiences, I have had similar observations (3-6 kHz plateau with 6dB or more). So far I had used the Asylum corrections but certainly Sean's corrections would lower this anomaly close to normal due to the 4dB difference between the two correction curves in that frequency range.

Another problem was that I found a significant high frequency roll-off (-10db or more) for frequencies above 12KHz. This roll-off was present and similar with several different speakers (Spendor S3/5, Mission 751, Omega Super3) and different electronics (Linn amps, Jolida tube amp). This would indicate a need for a correction of my SPL meter in that range as well. Measurements were done on a tripod, using the C-(neutral) weighting and slow response.

Any suggestions on the use of the SPL meter? What are the variations between different production dates of the SPL meter? Are there any, not too expensive (less than $300), alternatives? What about suggestions for a spectrum analyzer combined with a corrected microphone?

Thanks to everyone for their responses in advance. Also, many thanks to Sean and Clayton for posting the above corrections.
restock
Post removed 
Teonyc...I have used the digital readout RS meter together with the corrected tracks on the Rives test CD, and the results are in general agreement with my Behringer spectrum analyser. I agree that after you make your system (and room) "flat", you will probably want to tweek things a bit.
I believe the digital version of the RS SPL meter is the same as the analog, except for the display. I've used the compensation charts which seem to work well. But ultimately, I end up tweaking the settings based on how everything sounds.

I've also just ordered the Rives Audio Test CD2 and will let everyone know how it works out.
Are corrections for the digital RS SPL necessary and if so, have any ever been posted?
Restock...Behringer DEQ2496. $300 plus about $70 for the mic. Great unit. See Behringer website.
Post removed 
Rgodin, both corrections are for the analog Radio Shack SPL meter.

G_m_c, thanks for bringing up Rives Audio. Does anyone know what corrections the Rives CD uses? Also, I believe with the right corrections the SPL meter would be usable. I am just not sure what the variations between different SPL meters are and which correction curve is closest.

Eldartford, what spectrum analyzer and calibrated microphone are you using?
Rives Audio has info on this meter, along with downloads for corrections. They seem to think it is a pretty capable meter for "home" use.
I bet that the RS meter is being used, by audiophiles, for an application that it was not designed for...frequency response. The RS meter seems to be meant for measuring overall SPL, as for a factory environment, planes flying over, or your neighbor's lawnmower. For such uses flat frequency sensitivity is not very important. For the price it does very well.

I have been through the RS meter stage, and (sorry to repeat myself) have moved on to a real time spectrum analyser, which is the way to go.