(click thumbnail)Price: $39.95 Info: www.atiaudio.com
Anybody doing anything with sound measurements has probably used a Radio Shack sound pressure level meter. You know, the one with the yellow analog meter that was always $20-30. ATI's SLM-100, priced at $39.95, is a similar style SPL meter that is a bit more durable for pro use. These meters are useful in many applications; recording studios, live, broadcast. home studio, etc.
Compared to newer decibel meters with precise digital readouts, the SLM-100 uses the old fashioned analog meter. But it is still easy to use. The meter is lightweight and is powered by an internal 9V battery, hidden under a Philips screw-locked cover. The unit features switches for either A and C weightings and slow or fast response time. The blue-color, dB range selection dial ranges from 60 dB to 120 dB in 10 dB increments. The meter dial ranges from - 10 dB to +6 dB, with 0 dB used as the reference point for each range setting. Example: a measured 78 dB in the 80 dB setting reads as -2 dB on the meter.
The meter's rated frequency response is 32 Hz to 20 kHz, but there is a fast roll-off in frequencies above 10 kHz. The meter is more accurate between 32 Hz and 10 kHz. (-2 dB). The electret mic is omnidirectional. The meter is accurate to within 2 dB at 114 dB SPL.
Just like the Radio Shack meter of old, I found the ATI SLM-100 was easy to use. I used it to set up and match the levels of a new surround speaker system. The processor had its own noise and tone and generator. Since I was using mostly noise for reference, the A-weighting and the slow response settings worked just fine. Using warble tones, I did notice that the SLM-100 has a flatter bass response to 35 Hz or so than the Radio Shack meter. Overall, a useful tool that is inexpensive and indispensable.