Audio restoration

NG2 repair, NRNG and media grading

Control the sequential DeClick and DeCrackle stages, choose the S150 or S200 noise profile, then use the independent grading reference to keep automatic decisions and record comparisons consistent.

Applies to VinylRest Live 1.20b1 (build 45)

One audible chain, one independent reference

VinylRest Live separates the sound you hear from the condition measurement shown as the media grade. This is deliberate: changing a listening preference must not change the reference used to compare records.

Audible restoration
Runs fixed NG2 DeClick, then NG2 DeCrackle, then the current S150 or S200 NRNG mix. Its output can be heard as Repaired or inspected through the aligned Original, All, Clicks and Noise monitoring signals.
Grading reference
Sees the original captured stereo audio, supplies the rolling observations used by the three automatic controls and never changes the audible signal.
Important distinction: Applied Repairs shows what the audible repair engine actually changed. Grade detections belong to the fixed grading reference. They are intentionally different measurements.

One fixed NG2 generation

DeClick
The first independently controlled NG2 repair stage. It produces the candidate passed directly to DeCrackle.
DeCrackle
The second independently controlled NG2 stage. It repairs the already-DeClicked candidate without stacking another full processing window.
Exact bypass
Set either stage's manual sensitivity to 0. The stage becomes transparent and its Removed contribution becomes zero while prepared latency remains unchanged.

The release product displays NG2 as a fixed value. Generation selection and historical repair engines are diagnostic-build features and are not part of the product interface.

Sensitivity

Each stage has its own real integer sensitivity from 0 to 100. Higher values ask that stage to detect and repair more subtle events, but an unnecessarily high value can also alter legitimate transients. Manual values are preserved while Auto is enabled.

Recommendation: begin with the Paranoid profile and enable the Auto controls you want to evaluate. Paranoid is intentionally conservative and is the default for a new installation.

How automatic sensitivity works

DeClick Auto and DeCrackle Auto independently own their corresponding audible sensitivity. Each evaluates the same most recent rolling observation from the fixed reference engine but follows its own profile curve.

The Mac and WebApp show each effective value on its disabled slider while Auto is active. Turning that stage's Auto off restores the manual value that was preserved underneath. A delayed browser command cannot combine settings from two different repair revisions.

Correction profiles

Profiles do not change what the fixed detector hears. Each profile contains separate maximum curves for DeClick Auto, DeCrackle Auto and NR Auto. VinylRest Live interpolates between the limits, so the beginning of a grade receives less correction than the end when the profile values rise.

DeClick Auto maximums

GradeParanoidLightMidHigh
M5%10%10%20%
NM10%22%25%35%
VG+20%35%40%45%
VG30%48%55%60%
G+35%61%70%75%
G60%70%80%85%
F45%77%88%89%
P60%79%90%90%
Paranoid
The gentlest profile and product default. Use it when preserving musical transients is more important than removing every small defect.
Light
A gentle step up from Paranoid across all three restoration stages.
Mid
A balanced middle profile for records that need more restoration than Light.
High
A stronger response for damaged records. Listen carefully for changes to percussion and other sharp attacks.
Custom
Your own grade boundaries and DeClick, DeCrackle and NR maximums, saved from Settings → Grading.

DeCrackle Auto maximums

GradeParanoidLightMidHigh
M0%4%5%10%
NM1%9%12%15%
VG+3%14%18%20%
VG5%17%23%25%
G+7%21%28%40%
G9%25%33%50%
F11%29%38%55%
P15%30%45%60%

NRNG noise reduction

NRNG always follows both NG2 repair stages. Choose the conservative S150 profile or the stronger S200 profile. The branch is prepared and advanced even while bypassed, so Repaired and Original keep the same timing. Enabling NR, disabling it or changing the selected maximum uses a short transition and does not stop, flush or re-prime the audio stream.

NR
Enables the processed mix. When disabled, the time-aligned DeCrackled signal is copied to the output while the NRNG state continues in the background.
Manual maximum
Selects 1–12 dB. This value is preserved while NR Auto is active and returns when Auto is disabled.
NR Auto
Uses the current media grade's NR maximum from the selected profile, uses the Mint row until grading is available and clamps every stronger value to 12 dB.
Relearn noise
Starts a new P65 acquisition without rebuilding the transport. A new side starts one automatically after two seconds of qualified input.

Acquisition selects the first one-second run made from four consecutive qualifying 250 ms windows below the configured maximum capture level. The default is −55 dBFS. Until the profile is valid, NRNG is a delayed bit-transparent bypass and Noise monitoring is zero.

Grade boundaryParanoidLightMidHigh
M · Mint2 dB2 dB3 dB6 dB
NM · Near Mint4 dB4 dB6 dB9 dB
VG+ · Very Good Plus5 dB6 dB9 dB12 dB
VG · Very Good6 dB8 dB11 dB12 dB
G+ · Good Plus8 dB10 dB12 dB12 dB
G · Good10 dB12 dB12 dB12 dB
F · Fair11 dB12 dB12 dB12 dB
P · Poor12 dB12 dB12 dB12 dB

These are the effective release-product maxima; profile entries above 12 dB are clamped to the NRNG limit. The selected maximum is a ceiling, and the engine's frequency-dependent gain may apply less where music protection or confidence requires it.

What Activity shows: profile state, transition, gain mean and minimum, music protection, confidence, invariant violations and the latest automatic decision. These diagnostics explain how NRNG is operating; none is a promise of uniform attenuation across every frequency.

Understanding the media grade

The stable grade uses the median of complete, non-overlapping windows of about ten seconds collected since the last reset or automatically detected side change. Using a median prevents one unusually noisy passage from dominating the whole result.

GradeMaximum reference detections / s
M · Mint0.2499
NM · Near Mint0.7496
VG+ · Very Good Plus1.2993
VG · Very Good2.6486
G+ · Good Plus4.2977
G · Good8.8203
F · Fair17.6406
P · PoorAbove 17.6406
Not an official Discogs grade: this is an experimental measurement of defects detected in the captured audio. It cannot assess the sleeve, visual condition, pressing quality, cartridge setup or every kind of audible wear.

Reset grading

Reset grading when you intentionally begin a new record or want a fresh measurement. The audio does not stop and the Applied Repairs graph is preserved. DeClick and DeCrackle Auto use bounded fallbacks until a new rolling observation is complete. The next qualified side starts fresh NRNG acquisition.

Automatic side detection

After sustained input below the configured silence threshold, cumulative grading and Shazam recognition pause. Now Playing is cleared, but the previous grade remains visible. When audio returns, VinylRest Live waits for two seconds of sustained input before resetting cumulative grading and beginning a fresh Shazam search. The short rolling observation used by the automatic restoration controls continues during the pause.