Alesis io26 耳机口的RMAA测试
遇到一个麻烦，io26耳机口输出阻抗是32欧，而它的线路输入阻抗是16K欧，耦合的电平偏低。
先做一个测试，耳机音量调节到80％左右，直连耳机口和线路输入insert口，能够录到足够大的电平，成绩较好。
再做一个测试，耳机音量调节到30％左右，接上HD535耳机，再并联到线路输入insert口，经DAW放大，成绩勉强。
补充一个测试，耳机音量调节到30％左右，直连线路输入insert口，经DAW放大，成绩还可以。
Summary
Frequency response
Noise level
Dynamic range
THD + Noise (at -3 dB FS)
Intermodulation distortion
Stereo crosstalk
IMD (swept tones)
[ 本帖最后由 audiobarbird 于 10-6-19 03:06 编辑 ]
先做一个测试，耳机音量调节到80％左右，直连耳机口和线路输入insert口，能够录到足够大的电平，成绩较好。
再做一个测试，耳机音量调节到30％左右，接上HD535耳机，再并联到线路输入insert口，经DAW放大，成绩勉强。
补充一个测试，耳机音量调节到30％左右，直连线路输入insert口，经DAW放大，成绩还可以。
| Testing device | Alesis io26 |
| Sampling mode | 24-bit, 96 kHz |
| Interface | |
| Testing chain | headphone 1 80% (32ohm), insert in 3-4 (16Kohm) |
| RMAA Version | 6.2.3 |
| 20 Hz - 20 kHz filter | ON |
| Normalize amplitude | ON |
| Level change | -0.2 dB / -0.2 dB |
| Mono mode | OFF |
| Calibration singal, Hz | 1000 |
| Polarity | correct/correct |
Summary
| Frequency response (from 40 Hz to 15 kHz), dB | +0.01, -0.07 | Excellent |
| Noise level, dB (A) | -103.2 | Excellent |
| Dynamic range, dB (A) | 103.1 | Excellent |
| THD, % | 0.0030 | Excellent |
| THD + Noise, dB (A) | -87.8 | Good |
| IMD + Noise, % | 0.0041 | Excellent |
| Stereo crosstalk, dB | -98.2 | Excellent |
| IMD at 10 kHz, % | 0.0040 | Excellent |
| General performance | Very good |
Frequency response
| From 20 Hz to 20 kHz, dB | -0.11, +0.01 |
| From 40 Hz to 15 kHz, dB | -0.07, +0.01 |
Noise level
Left | Right | |
| RMS power, dB | -101.7 | -101.6 |
| RMS power (A-weighted), dB | -103.4 | -103.0 |
| Peak level, dB FS | -71.6 | -71.5 |
| DC offset, % | -0.0 | -0.0 |
Dynamic range
Left | Right | |
| Dynamic range, dB | +101.7 | +101.6 |
| Dynamic range (A-weighted), dB | +103.1 | +103.1 |
| DC offset, % | +0.00 | +0.00 |
THD + Noise (at -3 dB FS)
Left | Right | |
| THD, % | +0.0030 | +0.0030 |
| THD + Noise, % | +0.0037 | +0.0036 |
| THD + Noise (A-weighted), % | +0.0041 | +0.0041 |
Intermodulation distortion
Left | Right | |
| IMD + Noise, % | +0.0042 | +0.0041 |
| IMD + Noise (A-weighted), % | +0.0027 | +0.0027 |
Stereo crosstalk
Left | Right | |
| Crosstalk at 100 Hz, dB | -86 | -87 |
| Crosstalk at 1000 Hz, dB | -98 | -97 |
| Crosstalk at 10000 Hz, dB | -86 | -88 |
IMD (swept tones)
Left | Right | |
| IMD + Noise at 5000 Hz, | 0.0048 | 0.0047 |
| IMD + Noise at 10000 Hz, | 0.0037 | 0.0037 |
| IMD + Noise at 15000 Hz, | 0.0037 | 0.0036 |
[ 本帖最后由 audiobarbird 于 10-6-19 03:06 编辑 ]
并联HD535 30％音量的测试结果
Summary
Frequency response
Noise level
Dynamic range
THD + Noise (at -3 dB FS)
Intermodulation distortion
Stereo crosstalk
IMD (swept tones)
[ 本帖最后由 audiobarbird 于 10-6-18 22:02 编辑 ]
| Testing device | Alesis io26 |
| Sampling mode | 24-bit, 96 kHz |
| Interface | |
| Testing chain | headphone 1 30% (32ohm) with HD535 (150ohm), insert in 3-4 (16Kohm) +21dB |
| RMAA Version | 6.2.3 |
| 20 Hz - 20 kHz filter | ON |
| Normalize amplitude | ON |
| Level change | -1.3 dB / -0.4 dB |
| Mono mode | OFF |
| Calibration singal, Hz | 1000 |
| Polarity | correct/correct |
Summary
| Frequency response (from 40 Hz to 15 kHz), dB | +0.52, -0.26 | Good |
| Noise level, dB (A) | -93.2 | Very good |
| Dynamic range, dB (A) | 93.3 | Very good |
| THD, % | 0.0027 | Excellent |
| THD + Noise, dB (A) | -84.7 | Good |
| IMD + Noise, % | 0.097 | Good |
| Stereo crosstalk, dB | -82.6 | Very good |
| IMD at 10 kHz, % | 0.0081 | Very good |
| General performance | Very good |
Frequency response
| From 20 Hz to 20 kHz, dB | -0.26, +0.52 |
| From 40 Hz to 15 kHz, dB | -0.26, +0.52 |
Noise level
Left | Right | |
| RMS power, dB | -91.9 | -91.9 |
| RMS power (A-weighted), dB | -93.3 | -93.2 |
| Peak level, dB FS | -63.9 | -63.5 |
| DC offset, % | -0.0 | -0.0 |
Dynamic range
Left | Right | |
| Dynamic range, dB | +91.7 | +92.1 |
| Dynamic range (A-weighted), dB | +93.2 | +93.3 |
| DC offset, % | +0.00 | +0.00 |
THD + Noise (at -3 dB FS)
Left | Right | |
| THD, % | +0.0028 | +0.0027 |
| THD + Noise, % | +0.0069 | +0.0061 |
| THD + Noise (A-weighted), % | +0.0060 | +0.0056 |
Intermodulation distortion
Left | Right | |
| IMD + Noise, % | +0.0967 | +0.0981 |
| IMD + Noise (A-weighted), % | +0.0203 | +0.0232 |
Stereo crosstalk
Left | Right | |
| Crosstalk at 100 Hz, dB | -77 | -80 |
| Crosstalk at 1000 Hz, dB | -82 | -81 |
| Crosstalk at 10000 Hz, dB | -78 | -82 |
IMD (swept tones)
Left | Right | |
| IMD + Noise at 5000 Hz, | 0.0086 | 0.0076 |
| IMD + Noise at 10000 Hz, | 0.0086 | 0.0076 |
| IMD + Noise at 15000 Hz, | 0.0086 | 0.0076 |
[ 本帖最后由 audiobarbird 于 10-6-18 22:02 编辑 ]
直连音量30％
Summary
Frequency response
Noise level
Dynamic range
THD + Noise (at -3 dB FS)
Intermodulation distortion
Stereo crosstalk
IMD (swept tones)
| Testing device | Alesis io26 |
| Sampling mode | 24-bit, 96 kHz |
| Interface | |
| Testing chain | headphone 1 30% (32ohm), insert in 3-4 (16Kohm) +24dB |
| RMAA Version | 6.2.3 |
| 20 Hz - 20 kHz filter | ON |
| Normalize amplitude | ON |
| Level change | -0.2 dB / 0.8 dB |
| Mono mode | OFF |
| Calibration singal, Hz | 1000 |
| Polarity | correct/correct |
Summary
| Frequency response (from 40 Hz to 15 kHz), dB | +0.01, -0.07 | Excellent |
| Noise level, dB (A) | -92.1 | Very good |
| Dynamic range, dB (A) | 92.1 | Very good |
| THD, % | 0.0032 | Very good |
| THD + Noise, dB (A) | -83.7 | Good |
| IMD + Noise, % | 0.0082 | Very good |
| Stereo crosstalk, dB | -90.2 | Excellent |
| IMD at 10 kHz, % | 0.0090 | Very good |
| General performance | Very good |
Frequency response
| From 20 Hz to 20 kHz, dB | -0.11, +0.01 |
| From 40 Hz to 15 kHz, dB | -0.07, +0.01 |
Noise level
Left | Right | |
| RMS power, dB | -90.9 | -90.9 |
| RMS power (A-weighted), dB | -92.0 | -92.1 |
| Peak level, dB FS | -62.7 | -62.7 |
| DC offset, % | -0.0 | -0.0 |
Dynamic range
Left | Right | |
| Dynamic range, dB | +91.0 | +90.9 |
| Dynamic range (A-weighted), dB | +92.1 | +92.1 |
| DC offset, % | +0.00 | +0.00 |
THD + Noise (at -3 dB FS)
Left | Right | |
| THD, % | +0.0031 | +0.0032 |
| THD + Noise, % | +0.0074 | +0.0067 |
| THD + Noise (A-weighted), % | +0.0067 | +0.0064 |
Intermodulation distortion
Left | Right | |
| IMD + Noise, % | +0.0086 | +0.0079 |
| IMD + Noise (A-weighted), % | +0.0071 | +0.0065 |
Stereo crosstalk
Left | Right | |
| Crosstalk at 100 Hz, dB | -82 | -82 |
| Crosstalk at 1000 Hz, dB | -89 | -89 |
| Crosstalk at 10000 Hz, dB | -79 | -84 |
IMD (swept tones)
Left | Right | |
| IMD + Noise at 5000 Hz, | 0.0091 | 0.0088 |
| IMD + Noise at 10000 Hz, | 0.0091 | 0.0088 |
| IMD + Noise at 15000 Hz, | 0.0091 | 0.0088 |