HTC Desire HD [T-Mobile G10, HTC's official digital model is A9191, this phone uses Qualcomm Qualcomm MSM8255 chipset, we are only measuring the audio subsystem of this phone today. The model with the MSM8255 chipset is the first to be evaluated.
HTC Desire HD smartphone
HTC Desire HD Smartphone - Compare with HTC HD2
Here is a brief introduction to Desire HD. This phone can basically count the top products of the previous generation of Android phones. It is also the top model of the Qualcomm chipset MSM. The meaning of the MSM8255 chipset is the same as that of the QSD8250. At that time, it seems to be relatively QSD8250. Said that the MSM8255 progress is still very big. The MSM8255 is manufactured in a 45nm process. The core architecture is Cortex-A8, clocked at 1GHz, and the graphics unit is upgraded from Adreno200 to Adreno205. In theory, the 3D performance is doubled. The MSM7230 we introduced earlier, the difference with the MSM8255 is the main frequency is 800MHz. The MSM8255 chipset is also licensed by Dolby to support Dolby sound when the headphones are output. Let's start the assessment.
Objective test:
E-MU 1616M PCIe Digital Audio System
In accordance with established practice, we conducted a set of objective tests on the headphone output of Desire HD. The test was also in the form of a professional-grade sound card input, combined with common analysis methods to provide intuitive measurement results. In the test, we found that the output level of DesireHD is lower at the maximum volume, and the output of the standard level file generated by us is -14.8dB, but the internal signal overflows obviously. According to the frequency sweep analysis, we reduce the volume of Desire HD. In the two gears, the signal no longer overflows and the output level is -21.8dB. We compensated it to the standard level of 0 dB during the test by the recording device. In the test, we used the built-in audio player of the mobile phone to turn off the Dolby sound and play the WAV format test file.
HTC Desire HD [T-Mobile G10] Smartphone - Frequency Response Curve
| Test items | Test Results |
| Noise level, dB (A): | -86.2 |
| Dynamic range, dB (A): | 85.7 |
| Total harmonic distortion, %: | 0.011 |
| Intermodulation distortion, %: | 0.043 |
| Stereo resolution, dB: | 78.4 |
HTC Desire HD [T-Mobile G10] Smartphone - Frequency Scan
HTC Desire HD [T-Mobile G10] Smartphone - Separation Test
HTC Desire HD [T-Mobile G10] Smartphone - Separation Analysis
HTC Desire HD [T-Mobile G10] Smartphone - Frequency Scan @16bit 48KHz
From the frequency response curve of the RMAA test, we found that the Desire HD has a significant attenuation at high frequencies. This attenuation starts from 6KHz, and the frequency response is slightly abnormal. We even speculate that this frequency response may be an adjustment made by HTC to solve the apparent discomfort of Desire HD high-frequency signal overflow. Because we see from the maximum volume of Desire HD modulation, the output waveform level does not overflow, but the internal signal obviously overflows, which is originally a problem of the digital signal inside the chipset. Perhaps the designer perceives this problem from the subjective sense of hearing, so the output frequency response is greatly adjusted. From the RMAA test distortion index, it is basically the same level as the QSD8250.
Looking at the spectral analysis of the frequency sweep waveform, we have seen a similar situation encountered in the previous Qualcomm chipset. Noise around the frequency sweep waveform, various frequencies appear irregularly. From the point of view of noise intensity, it is slightly worse than the previous evaluation of HTC HD2 Android version. We also tested the frequency sweep waveform at 48KHz, and we still see the signal distortion caused by the obvious SRC under the Android system. Don't underestimate such a waveform. Such a serious overflow can be easily recognized by the ear. In the 10 Hz-20KHz sine wave scanning signal, we can hear the 4 parts of the singer. ".
Subjective hearing test:
Desire HD's sound performance style is similar to our previous HD2 evaluation under Android, but the output level value is different in volume control, but from the connection of ordinary headphones, its output level is not low, headphones The driving force is not weak, and the headphones with the GR07 have enough volume. However, the sound problem of Desire HD is similar to HD2 and is more serious. At the maximum of two volumes, although the frequency response has been significantly attenuated, the distortion caused by the signal overflow is very obvious, and the sounds of these two files become significantly rough. Overall, Desire HD sound level is the same as HD2, the sound is not clean enough, the resolution is normal, the image is poor, and there is a significant gap compared with iOS devices and ordinary portable players.
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