Last week, I received a test CD from Rives Audio. It has 2 sets of 1/3 octave test tones recorded from 20 Hz to 20 kHz. One set is the standard set of test tones and the second set is "corrected" for the Radio Shack meter. I used the RS corrected tones to measure my system, and I got some confusing results. I then had the following e-mail exchange with "technical support" at Rives Audio:
"My center channel speaker appears to have severely reduced output above 10kHz, (down ~25 dB compared to the 80 dB reference). I moved one of my mains in front of the CC and hooked it to the CC cable. It too has limited output above 10 kHz, but not quite as severe, (down ~20 dB). However, it was also about 2 feet closer to the meter, which may explain the difference."
Response fro Rives Audio:
"Above 10k, the RS meter is not terribly reliable. I would not be too concerned with measurements above 10k."
Reply from me:
"The Test CD is billed as having a set of tracks that are specifically corrected for the Radio Shack SPL meter. If the Radio Shack meter is really that unreliable above 10k, maybe you should delete tracks 59, 60 and 61, and instead include an explanation that the meter is too unreliable to correct at those frequencies. It would keep people, (like me) from freaking out thinking that a tweeter is blown."
Response from Rives Audio:
"That's a reasonable idea, but people would then freak out and buy other Test CD's that had the full bandwidth."
According to the charts in the links in the original post, the RS meter is within +/- 1 dB from 10k to 20 kHz. So, who's right? I'm thinking that my meter is damaged. I sure HOPE its not my speakers!
Lombardi said it:
Perfection is not attainable, but if we chase perfection we can catch excellence."