I use windscreen suction cups that came with my old Garmin navigation devices. They’re quite good 
Excellent idea! They are quite robust.
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Does any of you Direct Stream owners know for the mark and the value of power diodes? Are there four of them with three legs,or twoo only?
Do you know for resistors in signal path on analog board,are they Vishay Naked,as stated somewhere,i think?
The mod thread mentioned above has answers to these types of questions. If you don’t want to read all of it, you can read my posts there.
Anyway, all of the components are great quality and, in some cases, higher quality than many of the components that many modders use. The resistors in the audio path (and many other places) are surface mount thin film 0.1%, 25ppm/degree C, oversized (1/8 W) resistors and aren’t cheap. Naked Vishay usually refer to thru hole resistors which aren’t appropriate in this context. Even if there were physical room for the quality Vishays, the added inductance of having leads and the higher loop area allowing more RFI interference will in often cause inferior performance. I did audition the difference when I was prototyping the boards.
I’m not saying that the analog board is perfect, but most of the mods that people normally do won’t be improvements on the analog board. I didn’t cheap out on the passive components.
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So,it’s not possible to make analog board even better,than it is now? What mods do you suggesting? I did ordered Edcor transformers and this is great upgrade,the sound would be more alive and emotional,as stated by someone with these upgraded transformers…
I’m not saying the analog board is perfect, I’m just saying there is lower hanging fruit other places than the analog board proper. The mod thread has good suggestions and reports of things others found useful. Outboard 12V analog power supply is a possibility (you’ll need 1A). Shielding of EMI from things like the Bridge, display and digital board. As you’ve mentioned, a better fuse, better power supply components like bridge rectifiers, and better top-level regulators on the power supply board, but an outboard analog power supply lessens the need for these a little.
Some tips short of doing mods: If you have but don’t use the Bridge removing it will help. Turning off the display when not needed will help (it will briefly light up when you use the remote.) Not using high capacitance analog interconnects. If you listen to compressed pop music or loud orchestra, etc., keeping the volume level to 94 or below.
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Paul says,it will be redesigned model of this DAC this year,what that means,that you can do it even better,than it is now?It will be perfect then? What can you do to make it perfect? Outboard 12V analog power supply is a possibility (you’ll need 1A). What is included in this Power Supply,i am not knovledgeable about electronic terms?
Nothing is perfect. Always some noise will get in or out, all components have non-ideal parasitic actions. All clocks have jitter, etc.
Some main foci of the DS Mk II are to lessen groundloop interactions with other components of the system, to be less sensitive to power line noise and to lessen noise put back on the power lines, to better integrate into people’s systems, e.g. by having multiple analog attenuators settings instead of just 0dB and -20dB…
Once again, the Mk II thread has many answers:
Wishes Upcoming PSA DirectStream MKII - Audio Components / DACs - PS Audio
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So,because of parts it cannot be made better? How the Display can be turned off? I don’t have Bridge II installed,i do not stream,so,it will be better without…How much jitter this DAC does have?
This would mean desoldering SMD components, correct?
The remote control has a button labeled DIM, it shuts the display off. There’s also a brightness setting in the DAC that you can get to by pressing the Gear icon on the screen.
Jitter can’t be described by a single number. The phase noise spectrum is what matters for audio and the DS uses a very good clock and takes a lot of pain to keep the phase noise low. Still better power supplies, more shielding, etc. can help.
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No. The power supply board in the DS is thru hole. The digital and analog cards are surface mount.
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Yes,i did found it,thank you…i will install Master Clock in my CD Player with 75femtoseconds of jitter…how much jitter exactly this DAC does have?
As I mentioned a single number doesn’t tell you what you need to know about jitter. It’s phase noise that counts, especially phase noise in the audio spectrum. Femto clocks and clocks with < 50 femtoseconds of jitter may or may not have low phase noise in the audio spectrum. The DS uses a clock specifically designed to have low phase noise in the audio spectrum. Also the DS also doesn’t use a clock per se, but uses a low phase noise VCXO with a pull range of at least 100ppm to match the Redbook spec.
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Can you tell which parts would still make sense to exchange if an external PSA is used already? Maybe mark them on a photo and tell in case something should be considered that an experienced modder doesn’t know?
How do you know,if 75femtoseconds clock is having low noise? I have Neutrino New Class Master Clock,this is good clock in your opinnion? It is some 120$ worth…
As I said you need a low phase noise voltage-controlled oscillator with 100ppm pull range, not a fixed reference clock. The NewClassD site does have phase noise plots but they aren’t using standard equipment to measure it so it’s hard to compare their phase noise to other phase noise plots. Also, using wires to connect the power supply to the clock module and the clock output to the analog board will add noticeable phase noise. The purpose of having a low phase noise clock is to use it as close as possible to the reclocker in the device that separates the digital signal from the analog signal. The DS has less than 1/2" of impedance matched trace between the VCXO module and the reclocker. (Just leaving room for bypass caps.)
The DS uses the Crystek CVHD-957-22.57920 VCXO, the phase noise plots are in the datasheet.
https://www.mouser.com/datasheet/2/94/CVHD_957-1286850.pdf
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Aha,okay…but,it would be better,than original clock probably anyway even with wires,they are selling it as far better replacement for original clock…they says,it will be true highend CD player after…
Better than the VCXO in the DS? (along with its power supplies and control circuity), no. Better than the clock in high end MBL, dcS, etc.? Nope. Better than most DAC chip based DACs?, probably. Wires matter, they have to be impedance controlled with impedance controlled connectors on the ends, they have to not vibrate, they have to not pick up RF, etc. They have to not be in a ground loop. Common mode noise may be an issue, but filtering it would add jitter… Keeping waveform shape is important, but harder in long cables than short impedance controlled traces. Don’t get me wrong, the NewClassD seems well designed, but so is the clocking in the DS and there I had complete control over routing, power supplies, noise near the clock, etc. and, for example, use arguably better regulators than the NewClassD.
Once again, my point is that the things that people do with most DAC chip-based DACs to improve them often aren’t applicable to the DS. There are certainly improvements to be made, but most aren’t cost effective on the analog board (i.e. you can get better improvements from spending money on other, less sexy, improvements, like shielding, external analog supply…)
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