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Gear & Tone — plain-language explainers
Music knowledge / Guides and practical tools
About this reference
From the music-learning collection, adapted for Philojain Music Muse. Referenced sources remain credited in the article.
Guitars, amps, pedals and getting the sound you want.
The pitch number every tuner, pickup and pedal in this section answers to
ISO 16:1975 fixes concert A, on the treble stave, at 440 Hz, to be held “within an accuracy of 0.5 Hz.” That single reference sits underneath every article below whether it says so or not — a standard six-string guitar, a seven-string in drop tuning, and an amp sim’s built-in tuner are all ultimately checked against the same 440 Hz, just from different starting points. Extended-range instruments do not get a different reference pitch; they get more strings arranged around the same one.
The volume number worth knowing before you turn anything up
The other reference this section keeps returning to is CDC/NIOSH’s exposure guidance: a recommended exposure limit (REL) of 85 dBA over an eight-hour day, with a 3 dBA exchange rate that halves the same-risk exposure time for every 3 dB increase. NIOSH names 85–90 dBA for power tools and lawn mowers — a fair comparison for a solid rehearsal level — and 95 dBA and above for bulldozers, chain saws and, specifically, bars and nightclubs, a range a distorted rig at a small venue reaches easily. Getting the tone right and protecting your hearing while you find it are two separate jobs, and this section has articles that touch both.
Two kinds of “correct,” in one sentence: a guitar tuned to ISO 16’s 440 Hz within half a hertz and a rehearsal room held near NIOSH’s 85 dBA reference are both “right” by an actual published standard — one about pitch accuracy, the other about how long your ears can take it, and neither substitutes for the other.
Which reference does a given question actually need?
Pick what you are trying to get right, and see which of the two references above actually answers it.
Where this comes from
ISO 16:1975, Acoustics — Standard tuning frequency (Standard musical pitch): concert A at 440 Hz, held within 0.5 Hz. iso.org · accessed 4 August 2026.
CDC/NIOSH — Understand Noise Exposure (last reviewed 31 January 2024) and Noise-Induced Hearing Loss (last reviewed 30 January 2024): the 85 dBA/8-hour REL, the 3 dBA exchange rate, and the 85–90/95+ dBA example sources. cdc.gov/understand, /about · accessed 4 August 2026.
General reference figures, not a measurement of any specific instrument, amp or room. If your ears ring or sound feels dulled after playing, NIOSH names that as a warning sign regardless of any number above.
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