GB/T 10240-2026Specification for the editing and production of programme sources for the subjective assessment of sound quality of electroacoustic products and systems (English PDF)

4.1.1 Subjective evaluation of sound quality using program source content

4.1.1.1 Overview The program sources used for subjective sound quality evaluation include various audio products and systems that may be reproduced during the subjective sound quality evaluation. A typical representative of a type of program, or a program segment that makes a significant contribution to evaluating a certain sound quality attribute.

4.1.1.2 Voice Read aloud in Mandarin Chinese. Based on the probability of occurrence of its initials, finals, and tones, and its impact on the sound quality of electroacoustic products and systems. The evaluation of contributions was specially edited and produced.

4.1.1.3 Vocal Performance Vocal performance should include the following.

a) Solo singing by male and female voices. Generally, bass and soprano voices are used. Instrumental accompaniment is not recommended.

b) Choir. Mixed choir, children's choir.

c) Traditional Chinese Opera. Select representative opera styles and vocal techniques. This includes both a cappella singing and performances accompanied by traditional musical instruments.

4.1.1.4 Instrumental music Instrumental music should include the following.

a) Folk music. Solo and ensemble pieces on typical traditional Chinese musical instruments such as the suona, flute, xiao, erhu, yangqin, and pipa.

b) Western music.

---Piano music. The range should be at least five octaves.

---Orchestral music. String music includes passages played by string instruments such as the violin, viola, and double bass; wind music includes brass and woodwind instruments. The music includes sections played by wind instruments; percussion sections include sections played by percussion instruments such as timpani, snare drum, and triangle. Simultaneously... There should be ensemble sections for these instruments.

c) Electroacoustic Music. Representative electroacoustic instruments that have significantly contributed to the subjective evaluation of the sound quality of electroacoustic products and systems will be selected. Solo or ensemble passages.

4.1.1.5 Other Choose sounds such as bells, trains, birdsong, and steam whistles.

4.1.2 Check and adjust signals

4.1.2.1 Left and right channel check signals. speech or percussion.

4.1.2.2 Polarity check signal. Program signal with bass and treble percussion instruments.

4.1.2.3 Left and right channel balanced signals. The analog program signal shall comply with the provisions of GB/T 6278.

4.1.2.4 Sound level adjustment signal. The analog program signal shall comply with the provisions of GB/T 6278.

4.1.2.5 Reference Program Signals. Select some complete program segments with relatively complete artistic effects for reference when adjusting the equipment.

4.2 Recording requirements for evaluation program sources

4.2.1 Recording System A digital recording system should be used, with Pulse Code Modulation (PCM) as the audio encoding format and a sampling frequency of not less than 96kHz, quantization precision not less than 24bit.

4.2.2 Recording Environment For subjective evaluation of sound quality, the program source should be recorded in an anechoic chamber.

4.3 Evaluation of Program Source Technical Indicators

4.3.1 The spectrum range of the program source should not be narrower than 40Hz~18kHz.

4.3.2 The dynamic range of the program source should be no less than 50dB.

4.4 Evaluation of the audio quality characteristics of the program source

4.4.1 Qualitative requirements. The sound quality of each program segment in the evaluation source should be natural and realistic.

4.4.2 Quantitative requirements. When using a 5-point scoring system, the sound quality characteristic value of each program segment should not be less than

4.5 Requirements for Subjective Characteristics of Program Sources Used for Evaluation

4.5.1 The duration of each program segment should be between 10s and 60s. For orchestral programs, the duration can be appropriately relaxed, but should not exceed 5 minutes.

4.5.2 The replay volume of each program segment should be basically balanced.

4.5.3 The musical phrases in each program segment should be complete, with clean beginnings and endings.

4.5.4 All program segments are two-channel stereo signals, with accurate and realistic sound image positioning.

4.5.5 The ambient noise level for each program segment should be sufficiently low.

4.5.6 The overall information of the program source used for evaluation should not be lacking.

4.6 Program Source Storage Requirements The evaluation program source and the inspection and adjustment signals are stored uniformly in a designated digital carrier for use in copying the application version.

5.1 Requirements for the Production of Digital Audio Players

5.1.1 The electrical performance indicators of digital audio players should be superior to those specified in GB/T 15860.

5.1.2 Digital audio players should have automatic program playback and control functions.

5.1.3 During the original program source dumping process, data loss should be prevented.

5.2 Requirements for other digital carriers For program source applications using digital hard drives as the carrier, each program segment on the digital hard drive should be evaluated according to the requirements of the prescribed evaluation method. Line arrangement.