Standalone · macOS · iPad

loudness CORRECTLoudness correction to EBU R128 and ITU-R BS.1770-4

Offline loudness correction to EBU R128 / ITU-R BS.1770-4. Drop a file, pick a preset, correct it. Two-pass with verify-and-refine: hit your target within +/-0.1 LU, cleanly limited, no real-time guesswork.

Back to Shop
pegelWERK loudness CORRECT: original and target values side by side, EBU R128 preset, true peak and integrated on target
Highlights

Hit your target. Repeatable.

loudness CORRECT is the focused single-file solution for spec-compliant loudness correction. It shares its DSP engine with pegelWERK loudness METER PRO, same K-weighting, same loudness meter, same true-peak detector. What you see in the meter, you hit here.

BS.1770-4

K-Weighting + Double Gating

ITU-R BS.1770-4 K-filter (pre + RLB), 400 ms blocks at 75% overlap, absolute -70 LUFS and relative -10 LU gating. LUFS-I, LUFS-S Max, LUFS-M Max, LRA (EBU Tech 3342), every value exactly per spec.

True Peak

4x Polyphase TP Limiter

Identical polyphase taps as the TP detector, what it measures, it limits. 5 ms lookahead, dual-time-constant envelope, 50 ms exponential release. Clean flat limit curves, no pumping.

LRA

3-Band LRA Processor

Linkwitz-Riley 4th order with perfect reconstruction. Low <= 150 Hz, mid 150-3000 Hz, high > 3000 Hz. Per-band soft-knee compressor with RMS envelope. Band-specific time constants, pulls every LRA into the broadcast corridor.

Verify

Two-Pass with auto-refine

Pass 1 measures, pass 2 corrects, a third pass verifies. If the residual is above 0.1 LU, the correction pass runs again with trimmed gain. Result: your target hit within +/-0.1 LU.

Presets

14 delivery presets

EBU R128, R128 S1 short-form, ATSC A/85 (CALM), ARIB TR-B32, AGCOM, OP-59, DPP, Portaria 354, OTT -27 LUFS, Apple Podcasts, Spotify, Amazon Music, YouTube, plus custom. Tolerance window per preset, verify reports PASS / FAIL.

Surround

Mono to 9.1.6

Up to 16 channels, four routing layouts (Auto/ITU, Film L-C-R, DTS, Raw/Stems). LFE BS.1770-compliant with weight 0, surrounds at 1.41 in the power domain, exactly per spec, no creative interpretation.

By an experienced sound engineer
Built by an active broadcast engineer for broadcast engineers. No useless marketing features, only what actually gets used in the studio.
7-day risk-free trial
Download the full version, use it for a week in your real workflow, no account, no email, no credit card. Decide afterwards.
Reply from the developer
Support emails go straight to the developer's inbox, not into a ticket system. Usually within 24 hours on working days.
Delivery Presets

14 targets out of the box

From EBU R128 to OTT, from Apple Podcasts to YouTube. One click; the verify pass documents PASS / FAIL.

EBU R128
-23 LUFS · -1 dBTP
R128 S1
-23 LUFS · S max -18
ATSC A/85
-24 LUFS · -2 dBTP
ARIB TR-B32
-24 LUFS · -1 dBTP
AGCOM
-24 LUFS · -2 dBTP
FreeTV OP-59
-24 LUFS · -2 dBTP
DPP
-23 LUFS · -1 dBTP
Portaria 354
-23 LUFS · -2 dBTP
OTT -27 LUFS
-27 LUFS · -2 dBTP
Apple Podcasts
-16 LUFS · -1 dBTP
Spotify
-14 LUFS · -1 dBTP
Amazon Music
-14 LUFS · -2 dBTP
YouTube
-14 LUFS · -1 dBTP
Custom
Free choice
How it works

Four steps to spec

Drop, click, done. The two-pass pipeline runs in the background, you get a corrected file and a PDF acceptance report.

01

Drop file

WAV, AIFF, FLAC, MP3. Mono to 9.1.6, four routing layouts (ITU, Film, DTS, Raw). On macOS via file picker, on iPad via Files / iCloud Drive.

02

Pick preset

One of the 13 delivery targets, or custom with your own LUFS / TP / LRA values. LRA correction and TP limiter individually toggleable.

03

ANALYZE + CORRECT

Pass 1 measures LUFS-I/S/M, LRA, TP. Pass 2 writes a new file with static gain optional LRA multi-band correction TP limiter.

04

VERIFY + Report

Output is re-measured. If |residual| > 0.1 LU, pass 2 runs again. PDF report with source / target / result and PASS badge.

Technical Details

Built for Production

DSP parity with pegelWERK loudness METER PRO, same K-weighting, same loudness meter, same true-peak detector.

Standards & Engine

  • Standard ITU-R BS.1770-4 · EBU R128
  • K-Filter Pre + RLB
  • Gating Abs -70 / Rel -10 LU
  • Blocks 400 ms · 75% OL
  • True Peak 4x polyphase FIR
  • LRA EBU Tech 3342

Processing

  • TP-Limiter 4x OS · 5 ms Lookahead
  • Release 50 ms exponentiell
  • LRA 3-Band Linkwitz-Riley 4. Ordnung
  • Bands <= 150 / 150-3k / > 3 kHz
  • Verify Auto-Refine bei > 0,1 LU
  • Presets 13 + Custom

Platform & I/O

  • macOS 13+ Universal Binary
  • iPad iPadOS 16+ Landscape Dark
  • Input WAV · AIFF · FLAC · MP3
  • Output WAV / AIFF · 16/24/32 Bit
  • Channels Mono bis 9.1.6 (16)
  • Layouts Auto · Film · DTS · Raw
What sets it apart

Measure with sample accuracy.
Correct file-clean.

Real-time limiters have to guess, loudness CORRECT measures the file first, plans the correction, writes it cleanly, measures again, refines on deviation. That is how you hit targets exactly instead of approximately. Documented via PDF report, acceptance-safe, reproducible.