The existing decoder sounds a little plain, and a little digital, not balanced enough to listen, listening to it, thinking about changing one. A long time ago used the PCM1794 chip decoder, the sound balance atmosphere has an analog taste, good charm, perhaps the concept of DSD decoding at that time was too hot, and PCM1794 did not have DSD decoding, a hot head, bought a DSD decoding, and then sent the snubbed PCM1794 decoder to people... Why didn't anyone send me a machine or something, I also lacked...
Listening to listen to the fresh energy, but also listened to some other AK, ES with DSD decoding chip machine, found that the actual sense of hearing some will bring some digital sound or listening dissatisfaction (more expensive and better to hear can not buy), and taste the taste of PCM1794, always can not brazenly send the decoder to come back, then buy a new one.
Hand rice is not enough, or in the cost performance of the circle, turn around to see the natural sound of this DAC-1, but also with the PCM1794 classic chip, but also support their own replacement of CS4398 chip module double repair operation, CS4398 sound is relatively sweet and transparent. And look at the introduction of the circuit board on the 2 OPA2604 op amps are actually mounted on the op amp seat, not welded, what does it mean? You can manually pull out and replace other op amps to play, different op amp sound styles are different, with a rich taste, this is a good toy. Unshelling can see the circuit board inside the elna and WIMA capacitors, the material is sufficient, the specific replacement steps are detailed below.
In hand, look closely at the shell style is simple, some like a male mold, but also to reduce the cost of it, after all, it is not cheap to open a mold alone. The surface treatment is very meticulous, the panel is frosted, and the upper and lower shell drawing treatment is very fine.
The front panel boot button with halo light, boot light up the blue halo is very chic, the right is the source input blue indicator light and input toggle button, looking brighter. The back panel is common USB, fiber, coaxial input, RCA output, power socket.
It took a while to boot up, and sure enough, it was a familiar taste, so let's briefly say it.
high frequency:
PCM1794: Although it is an old chip, the analysis is still very strong, the details are rich, more delicate, and there is no common digital flavor.
CS4398: The lines are thinner and softer, smooth and delicate, with a sense of crystal clarity.
intermediate frequency:
PCM1794: Relatively thick, with some analog flavor, slightly bile machine flavor. The male and female voices are emotionally rich and infectious, and the stringed instruments have some thick and slightly sweet charm and some warmth.
CS4398: Sweet and delicate, the strings are like smearing the oil of the three gods, indulging in silkiness. The female voice is like drinking aphrodisiac holy water singing, delicate dripping, water spirit. Listen to "Chen Jieli - A Water Across the World", it feels like the bones are going to melt.
Low frequency:
PCM1794: Dive deep, quality and quantity control are very good, dynamic, plump and full, such as the general guarding the border, the momentum is stable.
CS4398: Soft and elastic, the strength is a little soft, the sense of layering is slightly lacking, such as the fairy pavilion dance, the style is soft.
Sound:
PCM1794: Magnificent, heavy lifting, performance symphony such a large scene full of momentum, small compilation is not a problem.
CS4398: The soundstage is generally dynamic, but the performance of female vocals and strings has a unique charm, sweet and charming.
If PCM1794 is a balanced atmosphere, CS4398 is a tender water fairy style. I can't imagine that this is just a thousand-yuan level decoder, the sound base quality is very good, and the sound performance can be comparable to higher-level products.
Disadvantages, of course, there is less DSD decoding, but many of the chip machines that support DSD decoding have no good sound than this PCM1794, or the real listening feeling is the most important. PCM1794 module output volume is slightly higher, my 80Wx2 (8 ohm) amplifier volume is adjusted to 9:30 position is very loud, CS4398 module output volume to 10:30 to adjust the equivalent, have to adapt slightly. After listening for a long time, I feel that the fineness of the high frequencies of this machine and the bouncing force of the low frequencies still have room for adjustment, and this should be adjusted to the personal favorite taste by changing the op amp.
Just do it. If you have a friend who has the same DIY idea as me and is not yet very skilled, you have to prepare carefully and carefully.
Materials/Tools: Dual Op Amp/Decode Chip Module, U-Shaped Puller, Tweezers, Screwdriver (Hex + Cross).
The DAC-1 decoder has 2 op amp positions, which are estimated to be I/V and LPF or other functions (amateur blind guesses, the master can guide), and the general J-FET input is suitable for I/V. Different op amps have different requirements for circuit characteristics, and being able to make a sound does not mean that it can make the best sound, and a circuit cannot perfectly play the potential of most op amps. You can change to 2 identical models or change to different or only 1 model, and adjust the listening style according to personal preferences.
OPA2604 is a double op amp, the replacement must also be the same double op amp (op amp has fakes, please be careful to buy), but also some are used with 2 single op amp magic welded to double op amp to use. Generally 8 feet of single or double op amp can be compatible with the same type of replacement work, some circuit characteristics may be some op amp matching compatibility is not very good, replaced by may be silent or noisy (confirm not to install reverse), but generally will not burn out, at least I did not encounter burned out, but really burned out what I am not responsible for Ha!
steps:
1. Wash your hands and let go of static electricity before you start, and then dry the water.
2. The machine is powered off, disassemble the 4 screws on both sides of the upper shell, take a picture of the circuit board op amp (decoding chip) area, and remember the front font direction of the op amp and the small dot corresponding to the 1-foot direction position.
3, with the U-shaped puller clamped to the op amp without pins on both sides of the vacancy level pulled out (to be stable and clever, can not use brute force), if the clip is not stable and crooked, the op amp pin may be crooked out and twisted into a stump of foot, at this time do not cry, with tweezers carefully clamped on the good. If the puller is not easy to use, the finger has some nails, you can find a suitable angle to cut by hand. If the transport and discharge seat is very tight and difficult to pull, you can first pick up one side a little, then pick up the other side a little, loosen some and then pull out. The decoding chip module is larger, and it is not easy to use the tool by hand.
4, the new op amp should be installed in accordance with the original op amp font direction and 1 foot corresponding position, if the two sides of the pin fork to be more open to the op amp socket jack, clip some can be smoothly inserted, and then check the previous photo to confirm that there is no problem, you can boot the audition. The decoding chip module pays attention to the printed words on the control board and the concave small semicircle/outer triangle orientation marking.
The following briefly says that the feeling of the individual in this DAC-1 (PCM1794 decoding module) decoder installed on the audition part of the op amp, only involves the difference in hearing sense, does not involve the quality level, only represents the personal preference of the personal device, does not guarantee that it is necessarily accurate, and what you hear may not be the same, if there is a difference, you are right.
5532DD: Compared with the previous 5532, it has improved the high and low frequency extension, more balanced, medium frequency taste is average, very cheap, very cost-effective. It's a bit inappropriate to use here.
AD827: Gorgeous sound, high and low frequency extension wide, medium frequency somewhat bland, low frequency elasticity and good volume feeling.
LME49720: Balanced and transparent, rich in detail, slightly moderate in medium frequency, appropriate low frequency.
OPA2604: Medium frequency is thick and bold, and the transverse sound field is wide.
MUSES8820: High frequency is soft and delicate, medium and low frequency is slightly ambiguous, good charm, low frequency is sufficient and somewhat soft.
MUSES8920: Balanced and natural, good high frequency detail overtones, good low frequency elasticity, appropriate volume.
MUSES01: Balanced and transparent, excellent analysis, rich high-frequency overtones, delicate moisturizing, low-frequency diving depth, appropriate tightening of the sense of volume, good elasticity.
MUSES02: rich and full, high frequency soft and delicate, medium and low frequency slightly ambiguous, good charm, low frequency sufficient and somewhat soft, and 01 is like two complementary styles.
Some op amps may take dozens of hours to use in a small pot to stabilize the sound, which will have less glitches and other sounds. After personally trying a variety of combinations, temporarily use THE MUSIC01+02 combination to listen (buy it is very expensive, do not listen to waste), high-frequency transparency (the track that is too bright to record may sound a little prickly), the low-frequency ambiguity elasticity is good, similar to the HORSES8920+8820 combination, which day to listen to the tired of changing other collocations to listen. As for what you like, listen to it for yourself.
Let's do this first, it is not easy to toss, it is time-consuming and laborious.