Audio channel test - 7.1

The 7.1 channels play one after another: first the channel name is spoken, then six seconds of pink noise. Checks the wiring of all eight channels, rear ones included. Flat container, 1:12.

audio-71-v2.0New · 08/10/2026

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2K · XCT-71-ChannelID_TST-1_F_EN-XX_INT-TD_71_2K_NULL_20261008_NUL_SMPTE_OV.zip · 992 MBSHA-256 2fcf697bae1e3e4fdb9e8367d9e7235e3e8a7a57ca80bc8fc9f6f042d52d24bd

What the package contains

Channel order: L, C, R, LFE, Ls, Rs, Bsl, Bsr. Every channel first speaks its name, then plays 6 s of pink noise, one channel at a time.
Level: Pink noise at -20 dBFS RMS on all channels, LFE band-limited to 30 to 120 Hz. The voice has the same loudness on every channel.
7.1 DS layout: DCP channels per ISDCF Doc4: L 1, R 2, C 3, LFE 4, Lss 5, Rss 6, Lrs 11, Rrs 12, with SMPTE MCA labels, so the rear channel wiring is checked too.
Picture: An auditorium model with the playing speaker group highlighted, the channel name, the DCP channel number and a timeline of the whole sequence.

How to use the test

1
Play the package in the auditorium with your usual processor volume.
2
The channels play one after another in the order L, C, R, LFE, Ls, Rs, Bsl, Bsr: first the channel name is spoken, then six seconds of pink noise.
3
The auditorium model on screen highlights the speaker that should be playing. Check that the sound really comes from it.
4
If another speaker plays or a channel is missing, the wiring or the channel mapping is wrong. The rear channels Bsl and Bsr sit on DCP positions 11 and 12 (7.1 DS layout).
5
The pink noise has the same level on every channel (-20 dBFS RMS), so you also hear level differences between channels. LFE plays only from 30 to 120 Hz.

Technical parameters

Container: Flat 1.85:1 · 1998 × 1080
Duration: 1:12 at 24 fps (1739 frames)
Bit rate: 100 Mbit/s
Audio: 16-channel PCM 24 bit / 48 kHz, 7.1 DS layout (ISDCF Doc4), SMPTE MCA labels
Authored with: DCP-o-matic 2.18
Standard: SMPTE DCP, unencrypted (no KDM), content kind TST
Picture: JPEG 2000 in MXF, X'Y'Z' 12 bit, gamma 2.6 (SMPTE ST 428-1)
Package: ASSETMAP, CPL, PKL, VOLINDEX and MXF in a folder ending in _SMPTE_OV, zipped

Versions

v2.0 (2026-10-08)
- First public release: the channels play in the order L, C, R, LFE, Ls, Rs, Bsl, Bsr. Each one speaks its name, then plays six seconds of pink noise at -20 dBFS RMS (LFE band-limited to 30 to 120 Hz).
- The sound is 16-channel PCM in the 7.1 DS layout (ISDCF Doc4) with SMPTE MCA labels. The screen shows an auditorium model with the playing speaker highlighted.

All releases: GitHub Releases · Free for projector alignment, commercial use included, under the licence CC BY-ND 4.0

Frequently asked questions

Does the test check the rear channels of a 7.1 auditorium?

Yes. The package has 16 channels in the 7.1 DS layout per ISDCF Doc4 (L 1, R 2, C 3, LFE 4, Lss 5, Rss 6, Lrs 11, Rrs 12) with SMPTE MCA labels. The rear channels Bsl and Bsr sit on positions 11 and 12, so the test shows whether they are missing or swapped in the chain.

Why does LFE sound only like a low rumble?

LFE plays pink noise only from 30 to 120 Hz, the subwoofer range. On a laptop or phone you will hardly hear it in the preview; in the auditorium the subwoofer should play it.

How long is the test?

1:12 at 24 fps (1739 frames). Each of the eight channels has a spoken name and six seconds of pink noise.

More test DCPs

DCI alignment pattern→Geometry, convergence, sharpness and colour channels in one chart, with Flat, Scope, F-200 and F-220 framing lines. Full container, 20 s @ 24 fps.Framing F-190 / F-210→F-190 and F-210 framing lines with masking arrows and pixel offsets, plus Flat, Scope and 16:9 for reference. Full container, 20 s @ 24 fps.Audio/video sync test→Shows whether the sound in the auditorium runs ahead of or behind the picture, and by how many milliseconds. Countdown, offset finder from -100 to +100 ms, clapperboard scene and an L, C, R and LFE channel check. Flat container, 1:03.

All test DCPs→

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