The Lepis P6 PRO is a portable audio player positioned at the high end, and its biggest selling point is the use of discrete R-2R DACs, that is, the use of multiple resistors to form the D/A conversion work. The working principle of R-2R is almost identical to that of the most primitive right-resistive DA, which is very different from the Delta-Sigma DAC. For music enthusiasts, with the inventory clearance of the PCM1704/1702 and the retro trend, the R-2R has also become one of the hot spots in the past two years. Due to the need for a large number of resistive components, the consistency of each resistor is extremely high. The price of the P6 PRO is also as high as 25,000 yuan.
LePit Luxury & Precision P6 PRO portable digital audio player
Appearance and main function
Lepi P6 PRO player, the appearance as shown in the photo, more traditional national brick shape, square, did not do the popular diamond cutting or rounded corner treatment in recent years. However, the rear side bottom cover of the solid wood that Lepi has insisted on since the beginning was retained. The metal thickness of several other surfaces is estimated to be not low, the fuselage is quite solid, for the current similar products, although we also call it a "portable" player, but mainly used to distinguish desktop equipment, want to be truly portable, 99% of the similar products on the market can not do it.
The bottom of the player is a USB Type-C port and a TF card slot. The machine itself integrates 64GB of storage space, but the write speed is really slow, about 10MB/s.
Other features of the player include support for LDAC, apt-X audio encoding reception in Bluetooth mode, and external decoder function in USB mode. Common audio formats are supported in player mode, including ISO files for DSDs. PCM specifications support up to 24bit/384kHz, and DSDs support DSD256.
LePit Luxury & Precision P6 PRO Portable Digital Audio Player - Setup Interface
Software part, Lepi uses its own LP OS, the specific core is unknown, but the official emphasis on non-Android Android, the actual use of the response speed is good, but the current UI and control point of view, also belongs to a relatively general level.
Core architecture and objective testing
Core architecture From the official technical introduction, we see the following internal main architecture and workflow diagram of the P6 PRO. As you can see, the left and right channels each use an R-2R DAC module, and then after doing I/V respectively, the output is to the next level. Before the amplification output and ear amplifier output, there is an LLMVS, which is the unique volume control technology of LePiga, the official introduction, the main feature is that the volume adjustment does not lose dynamics, even at small volumes. In actual use, it seems that the external presence is not high. The left and right channels of the ear amplifier are balanced independent outputs. Lepit Luxury & Precision P6 PRO Portable Digital Audio Player - Structure Diagram [Official]
The P6 PRO uses the R-2R scale to achieve the ideal dynamic range that can be achieved by 16 PCM1704s. Here's a quick look at how the right-resistive DA and R-2R D/A work. In the D/A course, everyone should have learned, taking 8-bit D/A as an example, the highest bit of D/A conversion is set to the resistance of R, the lowest bit is the 8th power of 2, and the resistance of 256R. The digital signal passing through this bit is distinguished by the large or small current being 0 or 1. But with this design, too much resistor R is used. R-2R is cleverly designed so that the entire circuit only needs two resistors, R and 2R, to be weighted by the current flowing through each bit [I, 1/2, 1/4...] Realize D/A conversion judgment of different digital signals.
In our PCM DAC audio applications, we may use at least 16bit, 24bit or even 32bit, which is still a huge requirement for the number of resistors. In addition, in addition to the need to ensure high accuracy and stability in the working environment of a single component, for example, HoloAudio's desktop equipment will also add an additional set of D/A to check each other and ensure accuracy. Therefore, these costs are greatly increased as a result.
In terms of digital signals, Lepi has evolved from the CPLD of that year to FPGA management, and the digital signal quality of Lepi players has always been good.
Objective testing The Lineout of the Leppo P6 PRO is consistent with the headphone output maximum voltage, the actual test single-ended output voltage is 2.5Vrms, and the balance is ±5Vrms [1kHz sine wave of 0dBFS], which is already large enough to cope with the SOUND pressure of the HEDDphone we are using. With the HIFIMAN HE1000, under the balanced output, ordinary music only needs a volume level of about 55 [up to 60]. We tested the headphone output single-ended, Lineout and balanced headphone output, Lineout and other objective indicators, headphone output and Lineout objective indicators are not significantly different. The following shows only select representative projects, not all of them. | Test the project | 44.1PO | 44.1LO | 44.1LO/FAST | 96PO | 96PO-BAL |
| Noise level, dB (A): | -96.4 | -96.3 | -117.9 | -117.8 | |
| Dynamic Range, dB (A): | 94.3 | 94.4 | 117.7 | -100.9 | |
| Total harmonic distortion, %: | 0.00327 | 0.00338 | 0.00328 | 0.00263 | 0.00258 |
| Intermodulation distortion, %: | 0.00663 | 0.00674 | 0.00664 | 0.00325 | 0.00324 |
| Stereo resolution, dB: | -96.8 | -96.1 | -115.6 | -115.2 |
LePit Luxury & Precision P6 PRO Portable Digital Audio Player - Frequency Response Sweep @Lineout
Lepit Luxury & Precision P6 PRO Portable Digital Audio Player - Frequency Scan @ Headphone Output 44.1kHz
LePit Luxury & Precision P6 PRO Portable Digital Audio Player - Resolution Test @Lineout 44.1kHz
LePit Luxury & Precision P6 PRO Portable Digital Audio Player - Resolution Test @ Headphone Output 44.1kHz
LePit Luxury & Precision P6 PRO Portable Digital Audio Player - Resolution Frequency Analysis @Lineout 44.1kHz
Lepit Luxury & Precision P6 PRO Portable Digital Audio Player - Resolution Frequency Analysis @ Headphone Output 44.1kHz
LePit Luxury & Precision P6 PRO Portable Digital Audio Player - Frequency Scan @ Headphone Output 96kHz
LePit Luxury & Precision P6 PRO Portable Digital Audio Player - Frequency Scan @Lineout 96kHz
LePit Luxury & Precision P6 PRO Portable Digital Audio Player - Frequency Scan @ Headphone Balanced Output - USB DAC Mode 96kHz
LePit Luxury & Precision P6 PRO Portable Digital Audio Player - Frequency Response Curve [Scan Tested] - THD Curve
Judging from the RMAA's signal analysis test, we even need to explain the RMAA test items. Its first frequency response curve is based on Multione, that is, a 20Hz-20kHz broadband signal [generally weighted white noise according to different test software or specifications], "buzzing", and it is measured. There is another frequency response test method that is the frequency sweep test of the sine wave, which is a narrow-band signal, "whine +++" so measured.
In fact, the Multitone's broadband signal is of course closer to the usual application. From the test point of view, in this case, the frequency response curve of the P6 PRO has a significant attenuation in the high-frequency part. 5kHz begins to decay, at 10kHz, it is reduced by about -1.5dB, to 15kHz is about -2.5dB, and about -3dB at 20kHz. In fact, above 15kHz, the impact of attenuation on subjective hearing should not be too large, but most of the devices we see now can achieve a frequency response curve of almost less than 0.1dB fluctuations, and it may be slightly uncomfortable to see this result. In addition, in the frequency sweep frequency response curve, its attenuation is lower, which is mainly manifested in the attenuation almost from 10kHz to just start, and to 15kHz attenuation is only about 1dB, 20kHz is about -3dB.
From the spectral frequency analysis plot of the 20Hz-20kHz frequency sweep, the frequency sweep of the P6 PRO is not clean, and there are many fine stripes, which indicates that there is some slight intermodulation distortion. However, after analysis and comparison, including equipment such as Izumi, which has tested Holo Audio in the past. This "pot" probably shouldn't have been backed by R-2R for unknown reasons. You can refer to the PCM1702's R2R2000 player test. Of course, due to JPG image compression, the pictures you see are weaker than the actual software. In addition, the P6 PRO player can support NOS and filter options after upswing, but it is not helpful for testing effects.
Lepit Luxury & Precision P6 PRO Portable Digital Audio Player - LDAC does not work bug frequency scan screenshots
In terms of DSD playback, the P6 PRO performs well. However, in Bluetooth mode, as shown in the figure, the noise floor of the LDAC is in a very abnormal state, so no further testing is done.
Subjective hearing
How does the Lepit P6 PRO sound? The small earbuds referenced in this test include the Water Moon Rain KATO, Softears Turii, Flyo FH7 Lap Iron, HIFIMAN HE1000 Headphones, and spoilers for the HEDDphone that is listening. Speaker system reference Airpulse A100 and our commonly used new Dirk A600 amplifier + Scanspeak D6620 treble + Vifa ne180w-08 6.5 inch mid-bass bookshelf box reference. Compare players such as Enjoy Sound MR1, Lotoo PawGold touch, HIFIMAN R2R2000 and so on.
First of all, don't think that the P6 PRO is an R-2R DAC product, it has the taste of traditional R-2R, slightly unexpected, really not. There is no taste of PCM1702 and PCM1704 on the HIFIMAN R2R2000, nor the taste of HoloAudio Trex and Spring, and the pursuit of R-2R thick sound, warm sound, solid mid-frequency these styles and trends, in general, do not belong to the P6 PRO.
So is there an R-2R device that is a little similar to the P6 PRO? There are, for example, 8 PCM1704 parallel Medieval CD players, Kenwood DPF-7002, of course, can only say that the trend is very similar. In addition, the style of the P6 PRO is really reminiscent of Lepi's pioneering work LP5 GOLD. Overall, P6 PRO still pursues an elegant and loose sound style, which is really neutral, fresh and elegant under the main body, and the more obvious pursuit of soft, delicate style. What is rare is that under the particularly loose style, the low frequency has better dynamics. In general, it can show the characteristics and advantages of sound when matching headphones, which is not as good as the speaker platform. So let's talk about matching speakers first.
Performance with speakers:The sound of the Lepit P6 PRO is extremely loose, the transient speed is slower, but there are very detailed high frequencies, which also makes its mid and high frequencies above the level clear, and calm, elegant and delicate. Whether it is paired with a sharp band treble or a silk membrane dome treble, the performance is quite soft. Although we see a certain amount of high-frequency attenuation in objective indicators, the actual hearing does not feel that the high frequency is dim. Of course, if compared with the ESS DAC, its high-frequency level is better, and the transient and hearing sense are also very obviously soft. In the speaker system, compared with the sound source of the AKM AK449x, the high frequencies are soft and delicate, but the P6 PRO is more relaxed.
In the mid-frequency and low-frequency parts, it still maintains a relatively slow transient, and the sound cannot be said to be relaxed, but it can be counted as calm. For the source that has just heard the stiff sound, switching to the P6 PRO may feel really a little anxious, but to a few large orchestra symphonies, you will feel its calmness, and layers, details. Of course, here I feel that there is a need to have certain requirements for the rear-end speaker amplifier style.
In terms of low frequency, the strength of the P6 PRO is average, the diving is better, and the pursuit of strength and speed is not its style. What is rare is that in the case of a more relaxed than the AKM AK449x series, it can bring better layers and even better explosive power.
Here's how it looks with headphones.
Treble performance:Users of P6 PRO believe that they should still choose a flat headset at least HIFIMAN Ananda and Edition XS level, and its loose listening sense can show more advantages in such a level of headphones. Don't expect any dynamics such as HD660s. When paired with small earbuds, the high gain of the P6 PRO, the high frequency part may be too strong, it is recommended to choose a lower gear.
Its high frequency is not obviously dark, the same shows a relatively loose and slow transient, in KATO, the high frequency quality is very high, the level is delicate, the delayed transient is extremely soft, but it sounds a bit weird, maybe the soft sound should really be darker to match. For the moving iron treble, this sense of relaxation is another taste, and the overall sense of hearing, the resolution is good enough. However, for some users who use in-ear headphones to pursue extremely dark backgrounds, the Pow Gold Touch is definitely on top of it. In addition, do not forget that in fact, this high-pitched style, AKM AK449x is also similar, as described in the speaker section above, the P6 PRO will be softer, but on headphones, this difference becomes significantly smaller.
Alto performance:In terms of vocal performance, the P6 PRO is a neutral thickness, but it is clearly soft style. Paired with headphones that were originally thicker, such as the HEDDphone, it will feel better. With the HE1000, which is relatively neutral and thin, or a few small earbuds, I didn't feel that it had much of a highlight when it was paired with headphones. In the symphony, classical music and other performances, the transient of the P6 PRO is still relatively soft, more typical is to listen to the piano, a more modern Yamaha piano, it sounds soft without a bright taste? In fact, that is to say, the dynamics of the P6 PRO intermediate frequency are actually relatively general. Of course, for this particularly soft style, some losses have been made, and under reasonable collocation, the performance is still very characteristic. However, if you want to match well on the headphone system, it may be more difficult, or it may be that it has no advantages.
Bass performance:The low frequency of the P6 PRO, when paired with small earbuds, hoop iron, HE1000, the control force is good enough, and the low frequency still maintains the elegance and calmness of the intermediate frequency and the overall style. However, for headphones with low frequencies themselves, this very slow transient is not suitable. On the speaker system, the calmness under the big dynamic, the relaxation of the sound, the strength, etc., can be compensated by the power amplifier with sufficient reserves. In the ear part, the P6 PRO currently has no features and highlights, so its performance, especially low-frequency performance, it is difficult to find the feeling under the speaker system.
summaryOverall, the P6 PRO, as the flagship model of the R-2R DAC, is very different from the solid medium frequency of many products of the R-2R that we are familiar with, and the robust medium and low frequencies, low frequencies, and particularly violent big dynamic performance is very different. But it is more like a product from Lepi, just like the LP5 Gold in 2014, the sound is elegant and delicate, the pursuit of rich layers, the pursuit of calm and delicate and even particularly soft listening. In use, it is more difficult to show the advantages of this soft and relaxed state with the speaker, and in the performance of the big dynamic, this style can form a contrasting beauty. In the ear amplifier part and the headphone matching part, this advantage is significantly reduced, more like a flagship model that stands out and adheres to the sound style of the Lepi brand.