Audio Professional FAQ
Frequently Asked Questions from rec.audio.pro
This rec.audio.pro FAQ
was compiled and written by
Gabe M. Wiener
with numerous contributions by others.
Many thanks to all who have contributed to the FAQ. Individual
contributions are credited at the end of their respective sections.
The core FAQ writers are listed below. The rubric in brackets will be
used to indicate who has written a particular section.
Scott Dorsey firstname.lastname@example.org [Scott]
Christopher Hicks email@example.com [Chris]
David Josephson firstname.lastname@example.org [David]
Dick Pierce email@example.com [Dick]
Gabe Wiener firstname.lastname@example.org [Gabe]
* Each author maintains and asserts full legal copyright on his
* contribution to the FAQ. Compilation copyright (C) 1996 by
* Gabe M. Wiener. All rights reserved. Permission is granted for
* non-commercial electronic distribution of this document.
* Distribution in any other form, or distribution as part of any
* commercial product requires permission. Inquire to
- 1.1 - What is this newsgroup for? What topics are appropriate here, and what topics are best saved for another newsgroup?
- 1.2 - Do I have to be a "professional" to post here?
- 1.3 - I need to ask the group for help with selecting a piece of equipment. What information should I provide in my message?
- 2.1 - How does one get started as a professional audio engineer?
- 2.2 - Are audio schools worth the money? Which schools are best?
- 2.3 - What are typical rates for various professional audio services?
- 3.1 - How are professional transmission lines and levels different from consumer lines and levels? What is -10 and +4? What's a balanced or differential line?
- 3.2 - What is meant by "impedance matching"? How is it done? Why is it necessary?
- 3.3 - What is the difference between dBv, dBu, dBV, dBm, dB SPL, and plain old dB? Why not just use regular voltage and power measurements?
- 3.4 - Which is it for XLRs? Pin 2 hot? Or pin 3 hot?
- 3.5 - What is phantom power? What is T-power?
- 3.6 - How do I interconnect balanced and unbalanced components?
- 3.7 - What are ground loops and how do I avoid them?
- 3.8 - What is the "Pin 1 problem" and how do I avoid it?
- 4.1 - What does it mean to "align" a tape machine?
- 4.2 - What is bias? What is overbias?
- 4.3 - What is the difference between Dolby A, B, C, S, and SR? How do each of these systems work?
- 4.4 - What is Dolby HX-Pro?
- 4.6 - How much better are external microphone preamplifiers than those found in my portable recorder?
- 4.7 - What is an MRL? Where do I get one?
- 5.1 - What is sampling? What is a sampling rate?
- 5.2 - What is oversampling?
- 5.3 - What is the difference between a "1 bit" and a "multibit" converter? What is MASH? What is Delta/Sigma? Should I really care?
- 5.4 - On an analog recorder, I was always taught to make sure the signal averages around 0 VU. But on my new DAT machine, 0 is all the way at the top of the scale. What's going on here?
- 5.5 - Why doesn't MiniDisc or Digital Compact Cassette sound as good as DAT or CD? After all, they're both digital.
- 5.6 - What is S/P-DIF? What is AES/EBU?
- 5.7 - What is clock jitter?
- 5.8 - What kind of cable AES/EBU or S/P-DIF cables should I use? How long can I run them?
- 5.9 - What is SCMS? How do I defeat it?
- 5.10 - What is PCM-F1 format?
- 5.11 - How do digital recorders handle selective synchronization?
- 5.12 - How can a 44.1 kHz sampling rate be enough to record all the harmonics of music? Doesn't that mean that we chop off all the harmonicsabove 20 khz? Doesn't this affect the music? After all, analog systemsdon't filter out all the information above 20 kHz, do they?
- 5.13 - Yeah, well what about square waves? I've seen square wavetests of digital systems that show a lot of ringing. Isn't that bad?
- 5.14 - How can a 16-bit word length be enough to record all the detailin music? Doesn't that mean that the sound below -96 dB gets lost in thenoise? Since it is commonly understood that humans can perceive audiothat IS below the noise floor, aren't we losing something in digitalthat we don't lose in analog?
- 5.15 - What's all this about 20- and 24-bit digital audio? Aren't CDs limited to 16 bits?
- 6.1 - What is a digital audio workstation?
- 6.2 - How is digital editing different from analog editing?
- 6.3 - What is mastering?
- 6.4 - What is normalizing?
- 6.6 - What is PCM-1630? What is PMCD?
- 6.7 - When preparing a tape for CD, how hot should the levels be?
- 9.1 - How can I play old 78s?
- 9.2 - How can I play Edison cylinders?
- 9.3 - What are "Hill and Dale" recordings, and how do I play them back?
- 9.4 - What exactly are NoNOISE and CEDAR? How are they used?
- 9.5 - How do noise suppression systems like NoNOISE and CEDAR work?
- 9.51 - Impulsive noise
- 9.52 - Broadband Noise
- 9.6 - What is forensic audio?
- 10.3 - How do I soundproof a room?
- 10.4 - What is a near-field monitor?
- 10.5 - What are the differences between "studio monitors" and home loudspeakers?
- 10.6 - My near field monitors are affecting the colors on my video monitor. What can I do to shield the speakers?
- 12.3 - How do I remove vocals from a song?
- 13.4 - Digital audio theory and practice
- 13.5 - Acoustics
- 14.2 - How do you spell and pronounce the FAQ maintainer's surname?