Extending the frequency range of other studio equipment
Even though an ADAT HD24 equipped with the EC-2 upgrade gives you the capability of recording audio beyond 40 kHz, many other elements of your studio may need to be upgraded to truly take advantage of this capability. Most studio equipment was designed to meet a 20-20 kHz spec, not the 44 kHz range that the EC-2 can record. Many devices treat anything above 20 kHz as nothing more than noise and may have low-pass filters that cut it off. To make truly wide-range recordings, make sure that every component of the signal chain is capable of ultra-wide response:
•Look for measurement microphones, usually small-diaphragm condensers, with response beyond 30 kHz. Most microphones are limited to 20 kHz response.
•An ideal mic preamp for 96 kHz recording should be flat to at least 70 kHz. Make sure the microphone preamp does not have built-in low- pass filters in an attempt to keep RF (radio frequency) noise out of the circuitry. They still need some filtering, but a well-designed preamp filters out RF without filtering audio.
•Many mixing consoles also have internal filtering to cut down on crosstalk, etc. These are often critical to low noise operation, so in some cases your best bet is to bypass the console during tracking and save it for only the final mix. Plug high-grade microphone preamps directly into the balanced inputs of the HD24/EC-2. Or, have your console custom- modified to raise its low-pass point by someone who understands the tradeoffs between noise, stability, and frequency response.
•For listening to a high-sample-rate recording, electrostatic headphones (e.g., Stax) or monitors with electrostatic or ribbon tweeters are your best bet. Most studio monitors don’t respond well to frequencies above 25 kHz, if they respond at all. A soft-dome tweeter trying to reproduce 30-40 kHz often goes into irregular modes that may, oddly, sound “good” to a listener, but they’re not really playing back what was recorded.
If you’ve done all the above, and confirmed your studio’s capability of reproducing the full range of frequencies the HD24/EC-2 can record, you now have a truly state-of-the-art studio that’s capable of mastering audiophile-quality DVDs and SACDs. Though the extra octave of high end may not be audible to the majority of listeners (or even to you, especially if you’ve been listening to loud music for too many years), you can be assured that what you’re recording will stand the test of time, for all listeners. Audio technology won’t get significantly better than this.
Good luck and thank you for using the ADAT HD24 with the EC-2 96 kHz Upgrade!
