GB/T 12105-2026General technical requirements for electronic keyboards (English PDF)

5.3 Acoustic Quality

5.3.1 Legal System The twelve-tone equal temperament should be adopted.

5.3.2 Standard Pitch The 'a' sound in the first octave should be 440Hz.

5.3.3 Tone High-end frets should simulate a realistic tone, mid-range frets should simulate a fairly realistic tone, and entry-level frets should simulate a reasonably realistic tone.

5.3.4 Timbre Name It should comply with the provisions of Chapter 4 of GB/T 33722-2025.

5.3.5 Sound Quality It should comply with the provisions of Table 2.

5.3.6 Pitch fine-tuning device For those with pitch fine-tuning devices, the adjustable range should be greater than (inclusive) -50 cents to 50 cents, and have a reset function.

5.3.7 Permissible pitch error within the reference pitch group Using f~e1 as the reference pitch group, the permissible pitch error within the reference pitch group should conform to the provisions of Table 3.

5.3.8 Pitch stability Within the reference pitch group, the pitch variation of the same key should not exceed 2 cents.

5.4.1 Keyboard

5.4.1.1 Difference between the key drop depth and the white key drop depth of the entire keyboard It should comply with the provisions of Table 4.

5.4.1.2 Surface height difference of white bonds It should comply with the provisions of Table 5.

5.4.1.3 Key Movement The keys should be sensitive and not rub against each other; there should be no mechanical noise that affects the sound of the performance when pressing and releasing the keys; the keys should return to their original position quickly when released. Viscous.

5.4.1.4 The starting point of sound production on the piano keys It should be located at 1/3 to 3/4 of the sinking depth.

5.4.1.5 Key Load It should comply with the provisions of Table 6.

5.4.1.6 Load difference between two adjacent white keys and two adjacent black keys on the keyboard The value should not exceed 0.15N.

5.4.1.7 Key width and spacing It should comply with the provisions of Table 1 in QB/T 4131-2010.

5.4.1.8 Key Surface It should be flat and free from obvious shrinkage, scratches, cracks, stains, sharp edges, or other defects.

5.4.1.9 Key Durability After the durability test in section 7.4.1.9, the piano keys should not exhibit any defects that affect performance.

5.4.1.10 Force Keyboard The range of intensity variation should not be less than 26 dB.

5.4.2 Volume pedal interface When the volume pedal is connected, it should be able to fully represent the changes in volume and volume, and its sound pressure level change range should not be less than 30dB.

5.4.3 Sustain Function

5.4.3.1 Sustain Button There should be a noticeable sustain effect; the sustain time of the C1 note should not be less than 3 seconds.

5.4.3.2 Sustain Pedal Interface When the sustain pedal is engaged, there should be a noticeable sustain effect; the sustain time for C1 should not be less than 5 seconds.

5.5 Electroacoustic performance

5.5.1 Noise Level It should comply with the provisions of Table 7.

5.5.2 Total Harmonic Distortion of the Sound System It should comply with the provisions of Table 7.

5.5.3 Signal-to-noise ratio at the line output It should comply with the provisions of Table 7.

5.5.4 Maximum sound pressure level of a single key tone in the reference pitch group Using f~e1 as the reference pitch group, the maximum sound pressure level of a single key tone within the reference pitch group should conform to the provisions of Table 7.

5.5.5 Maximum volume variation of adjacent musical notes on the full keyboard It should be even and without any jumps.

5.5.6 Changes in Sound Pressure Level The force required varies with the feel, and there is no significant difference in the force response between adjacent keys.

5.5.7 Wireless MIDI Transmission It should not affect the musical expression.

Note. This applies to products with wireless MIDI transmission and reception capabilities.

5.5.8 Polyphony It should comply with the provisions of Table 1.

5.6 Safety Performance

5.6.1 Security It should comply with the relevant provisions of Chapters 4 to 6, 7.6, and Chapters 8 to 10 of GB 4943.1-2022.

5.6.2 Electromagnetic Compatibility. Radiated and Conducted Emissions It should comply with the provisions of Appendix A in GB/T 9254.1-2021.

5.6.3 Harmonic Current Limits It should comply with the provisions of Chapter 7 of GB 17625.1-2022.

5.6.4 Radio Frequency Specifications It should comply with the provisions of Chapter 5 of YD/T 3168-2016.

Note. This excludes low-power short-range radio transmitting equipment.

5.7 Power Adaptability

5.7.1 AC power supply The product should be able to operate normally within a frequency range of (50±1)Hz and a voltage range of (220±22)V.

5.7.2 DC Power Supply The product should be able to operate normally when the rated voltage deviates by ±10%.

5.8 Appearance and Structure

5.8.1 The surface of the instrument body should be free from burrs, bubbles, cracks, deformation, obvious scratches, and overflow of the filling.

5.8.2 Metal parts should be free from rust, and plating or coating should not peel off.

5.8.3 Structural components should be free from mechanical damage.

5.8.4 The control elements should be complete, the action should be sensitive, and the control effect should be effective.

5.8.5 Text and symbols should be clear.

5.9 Environmental Testing After the

7.9 test, the product shall comply with the provisions of 5.3.2, 5.3.5~5.3.8, 5.4~5.8, and 5.11.

5.10 Limits for Hazardous Substances It should comply with the relevant provisions in GB 28489.

5.11 Energy Consumption It should comply with the provisions of

6.1.2 in GB/T 37878-2019.

7.3 Acoustic Quality

7.3.1 Legal System After powering on for 10 minutes, reset the pitch to piano, organ, or clarinet tone with velocity off (if there is no velocity off function). The settings (available in MIDI maximum velocity settings) can be checked using a measuring device with a resolution of no more than

0.5 cents.

7.3.2 Standard Pitch After powering on for 10 minutes, reset the pitch to piano, organ, or clarinet tone with velocity off (if there is no velocity off function). The settings allow you to use the velocity corresponding to the maximum MIDI value. Use a measuring device with a resolution of no more than

0.5 cents to check the A note in the first octave.

7.3.3 Tone Sensory inspection.

7.3.4 Timbre Name Sensory inspection.

7.3.5 Sound Quality Sensory inspection shall be conducted in accordance with the conditions specified in

5.3 of GB/T 31109-2014.

7.3.6 Pitch fine-tuning device After powering on for 10 minutes, reset the pitch to piano, organ, or clarinet tone with velocity off (if there is no velocity off function). The settings (available in MIDI maximum velocity settings) can be checked using a measuring device with a resolution of no more than

0.5 cents.

7.3.7 Permissible pitch error within the reference pitch group After powering on for 10 minutes, reset the pitch to piano, organ, or clarinet tone with velocity off (if there is no velocity off function). The settings (available in MIDI maximum velocity settings) can be checked using a measuring device with a resolution of no more than

0.5 cents.

7.3.8 Pitch stability After the test in 7.3.6, the test piano was powered on continuously for 2 hours, and then the same method was used to test it again. Then, the same key position was tested twice, before and after. The difference in measured pitch points is compared and checked.

7.4.1 Keyboard

7.4.1.1 Difference between the key drop depth and the white key drop depth of the entire keyboard Place a 300g weight on the surface of the piano keys, with the center of the weight 15mm from the front end of the top surface of the key. Press the key down, then press the weight down from the top surface of the white key. Use a length measuring tool to check at a point 2mm from the front edge and 5mm from the front edge of the black key; after testing, record the maximum and minimum sinking depths. difference.

7.4.1.2 White bond surface height difference Use a length measuring tool to check.

7.4.1.3 Piano Key Movement Sensory inspection.

7.4.1.4 Piano Key Initial Sound Point After powering on, play the piano with velocity off (if there is no velocity off setting, you can use the velocity corresponding to the maximum MIDI value). The key was checked using length measuring tools and by listening.

7.4.1.5 Key Load With velocity off (if there is no velocity off setting, use the velocity corresponding to the maximum MIDI value), use a force meter or weights on the instrument. Gradually add weights 10mm from the front of the key surface (with the center of the bottom surface as the reference) until the sound is produced.

7.4.1.6 Load difference between two adjacent white keys and two adjacent black keys on the keyboard After the test in 7.4.1.5, calculate the load difference between two adjacent white bonds and two adjacent black bonds.

7.4.1.7 Key width and spacing Use a length measuring tool to check.

7.4.1.8 Key Surface Sensory inspection.

7.4.1.9 Key Durability Play the keys continuously using the keyboard's striking mechanism at a force of 1.96N~2.94N and a speed of 2~3 times/s, 10mm from the tip of the keys. Sensory inspection after 1 million times.

7.4.1.10 Force Keyboard Use the tone of an organ or clarinet to lightly and heavily pluck the keys, and check according to the method specified in

5.20.2 of QB/T 4487-2013.

7.4.3 Sustain Function

7.4.3.1 Sustain Button Press the sustain button, play the key again with the piano tone, and then quickly release the key. Use a stopwatch to measure the output sound pressure level as it gradually decreases from the maximum sound pressure level to... The duration of 35dB (A-weighted).

7.4.3.2 Sustain Pedal Interface Engage the sustain pedal, depress it, and then quickly release the key after striking the piano note. Use a stopwatch to measure the output sound pressure level from maximum. The time it takes for the pressure level to gradually decay to 35 dB (A-weighted).

7.5 Electroacoustic performance

7.5.1 Noise Level Test using the following steps.

a) Place the instrument under test in a quiet room where the ambient noise level is below 20 dB (A-weighted);

b) As shown in Figure 1, place the piano under test horizontally on the test platform, and position the sound level meter at the reference point (the midpoint between the center lines of the left and right speakers). 500mm directly above;

c) Set the sound level meter parameters to A-weighted, Fast, and MAXHOLD.

d) Turn the volume of the instrument under test to the maximum and record the decibel value on the sound level meter as the noise level.

7.5.2 Total Harmonic Distortion of the Sound System Input a sine wave from 300Hz to 5000Hz. High-end and mid-range products should have a sound pressure level of no less than 80dB, while entry-level products should have a sound pressure level of no less than 70dB. Under the conditions described in section

5.9 of QB/T 4487-2013, check the instrument or use an audio analyzer.

7.5.3 Signal-to-noise ratio at the line output Under the conditions of inputting a 1000Hz sine wave and outputting a signal with a THD of 1%, the method described in section

5.10 of QB/T 4487-2013 is used to detect... Check; or use an audio analyzer to check.

7.5.4 Maximum sound pressure level of a single key tone in the reference pitch group Test using the following steps.

a) Place the instrument under test in a quiet room where the ambient noise level is below 20 dB (A-weighted);

b) As shown in Figure 1, place the piano under test horizontally on the test platform, and position the sound level meter at the reference point (the midpoint between the center lines of the left and right speakers). 500mm directly above;

c) Set the sound level meter parameters to A-weighted, Fast, and MAXHOLD.

d) Turn the volume of the piano under test to maximum, use the piano tone, and enable velocity control (if there is no velocity control setting, you can use...). (The maximum velocity corresponding to the MIDI value), play the keys in the reference tone group f~e1 one by one, and record the decibel value on the sound level meter, as the base... Maximum sound pressure level of a single key note in the pitch group.

7.6 Safety Performance

7.6.1 Security According to Chapters 8 and 9, Appendix B, Appendices E to G, Appendix M, Appendix O, Appendix S, and Appendix V of GB 4943.1-2022 The method described in Appendix Z is used for inspection.

7.6.2 Electromagnetic Compatibility. Radiated and Conducted Emissions Check according to the methods described in Appendix B, Appendix C and Appendix D of GB/T 9254.1-2021.

7.6.3 Harmonic Current Limits Check according to the methods described in Appendix A, Appendix B and Appendix C of GB 17625.1-2022.

7.6.4 Radio Frequency Specifications Check according to the method described in

6.2 of YD/T 3168-2016.

7.7 Power Adaptability

7.7.1 AC power supply When the AC power supply voltage with a frequency of (50±1)Hz is adjusted to 198V and 242V respectively using a voltage regulator, the instrument is played for testing.

7.7.2 DC Power Supply Use a voltage regulator to create a ±10% deviation from the rated operating voltage, and then play a test.

7.8 Appearance and Structure Sensory inspection.

7.9 Environmental Testing Check according to the method described in GB/T 12106-2026.

7.10 Limits for Hazardous Substances Check according to the method described in GB 28489.

7.11 Energy Consumption Check according to the methods described in

7.5.2.3 of GB/T 37878-2019.

8.2 Factory Inspection

8.2.1 The sampling plan for factory inspection shall comply with the provisions of GB/T 2828.1-2012 regarding the single sampling plan for normal inspection.

8.2.2 The inspection items, requirements, test methods, inspection level, and Acceptable Quality Limit (AQL) for factory inspection shall comply with the provisions of Table 8.

8.2.3 If the product fails the factory inspection, the batch shall be returned to the manufacturer for rectification of the non-conforming items. The rectified product may be resubmitted. Inspection. Resubmission of non-conforming batches shall be carried out in accordance with the provisions of section

7.6 of GB/T 2828.1-2012.

8.3 Type Testing

8.3.1 Product type testing shall be conducted annually. This testing may be conducted when changes occur in the structure, manufacturing process, or main raw materials that may affect product performance. It should also be carried out when production resumes after a shutdown of more than 6 months, or when required by the national quality supervision department.

8.3.2 Samples for type testing shall be randomly selected from currently manufactured products that have passed factory inspection.

8.3.3 Except for the limit testing items for hazardous substances, the sampling plan for type testing shall comply with discrimination level I in GB/T 2829-2025. The single sampling plan specifies that the nonconforming quality level (RQL) is 50, the decision array for class A is (0 1), and the decision array for class B is (1 2).

8.3.4 Sampling inspection of hazardous substance limits shall be conducted in accordance with the provisions of GB 28489.

8.3.5 Type testing is a full-item test. The test items, requirements, test methods and non-conformity categories shall comply with the provisions of Table 9.

8.3.6 If the type test is passed, the products produced in this cycle are qualified products.

8.3.7 Products that have undergone type testing should not be shipped as qualified products.