Acknowledgement: Claude Sonnet 4.6 (Anthropic) was used to vet specifications, trace provenance of all data used in this system, provide engineering estimates for missing data, code the optimization algorithm, and prepare the first draft of the user guide.
This tool is under active development. Specifications are sourced from manufacturer datasheets, published measurements, and topology-based estimates documented in the companion JSON data files. Use at your own risk. Results are intended as guidance for initially setting gain levels. Use your own ears to adjust and refine these levels as needed.
Values for this genre are derived from first principles — published measurement data is limited. Consider adding 2–4 dB extra headroom when setting input levels.
⚠ Beyond direct-field range
Beyond ~8 m in a reverberant hall the ISL formula overstates SPL reduction. Treat these values as approximate.
Recommended SPL Values — 24-bit recorder
Loudest (fff)
--
dB SPL
Quietest (ppp)
--
dB SPL
Dynamic range
--
dB
Headroom (24-bit)
--
dB
Set gain: fff peak at −-- dBFS
ℹ Data note
🎙 Sound check
Instrument Family & Source
Typical genres:
ISL: slant distance = √(horiz² + height²)
ℹ DI (line-level) source
Values are in dBu relative to nominal line level (+4 dBu professional). ISL scaling does not apply — distance is not relevant for DI signals.
▶ Gain staging note
ℹ Voice type note
⚠ Large distance adjustment
ISL scaling is most reliable within 1–3× the reference distance. Room reflections reduce the actual SPL change at larger departures.
Recommended SPL Values — 24-bit recorder
Loudest (fff)
--
dB SPL
Quietest (ppp)
--
dB SPL
Dynamic range
--
dB
Headroom (24-bit)
--
dB
Set gain: peak at −-- dBFS
ℹ Vibrato / SPL oscillation
✓ Values ready for the Optimizer
Loudest SPL: --
|
Quietest SPL: --
Enter these values in the “Loudest program material” and “Quietest program material” fields of the Gain Staging Optimizer.
Performance & Venue
dB SPL
dB SPL
dB
SPL ref sent:
35 dB SPL
Microphone
Tonal character
Note: Custom entries are used for this session only. Your entry will also be logged as a device request -- click Download all device requests below to export the log as a JSON file for submission.
✓ Added. Device request logged.
Preamplifier
dB
Character
Note: Custom entries are used for this session only and logged as a device request.
✓ Added. Device request logged.
Shure A15AS Attenuator (optional)
Position:
Attenuation:
Optimizer recommendation
Run optimization to see recommendation.
A15AS: input Z 1 kΩ, output Z 150 Ω, flat +/-0.5 dB 20 Hz-20 kHz. Phantom power passes through in both positions. Mic → Pre position note: Shure states the pad adds 215 ohm series simplex-powering resistance in the phantom supply path. For most condensers this is negligible; for high-current mics (Earthworks M50, QTC40 at 10 mA) it may reduce phantom voltage by a few volts -- monitor for any change in mic behavior. Pre → A/D position: Phantom supply is entirely upstream; the 215 ohm note does not apply.
A/D Converter
Note: Custom entries are used for this session only and logged as a device request.
✓ Added. Device request logged.
Signal chain
Microphone output levels
Preamplifier settings
Shure A15AS
A/D converter settings
Select all → Copy → Paste into cell A1 of a new Google Sheet.
Google Sheets will automatically split the columns. Mac: Cmd+A then Cmd+C | Windows: Ctrl+A then Ctrl+C.