Phison Audio PD2 Preamp/DAC

[Mivera Audio]

Oh and I forgot to explain the filtering. That's all done in the server. It's a separate piece from the DAC.

 

[FlexibleAudio]

Yes you pretty much got it figured out. The main difference between the sound of the GG vs the PD2 (besides the DAC section) is the tube output stage vs discrete Jfet folded cascode transistor. So all boils down to personal taste. Like I posted earlier, my 1st PD2 client owned both a GG and MSB DAC and this is how he said they compare:

"The PD2 really allowed me to differentiate between the two amplifiers but with the PD2 and Magico S1MkII it made both very enjoyable to listen to for long listening sessions. Even with the Bryston, at moderate volumes the music sounds so pure with that analog like sound. There seems to be just the slightest hint of warmth giving it a very natural type sound which I really like and it does this without sacrificing details which it seems to excel at (micro details). Although with different speakers at the time, this natural warmth with details reminds me of the MSB Dac but with that DSD liquidity of the Golden Gate Dac using it's DSD mode. To a lesser degree than either one (MSB Dac IV had more micro detail with PCM but was slightly drier, relatively speaking and Lampizator GG definitely sounded more smooth or I would describe as "wet"). The balance the PD2 strikes fits my preferences almost perfectly."

Ya that quote is what got me all riled up about doin a shoot out before.

But going back to my question, am I correct that both the PD2 and Lampi are "dac chipless" and just filter? if that is the case how does the Lampi filter compare to the PD's fancy approach? I am curious about the differences. I don't think its programmable field stuff; is it just discreet components?

I know when I talked to Andreas a few time he felt it necessary to upsample well beyond 64 to get rid of noise when a filter only (dac chipless) approach is employed.

 

[Mivera Audio]

Ya that quote is what got me all riled up about doin a shoot out before.

But going back to my question, am I correct that both the PD2 and Lampi are "dac chipless" and just filter? if that is the case how doe the Lampi filter compare to the PD's fancy approach? I am curious about the differences. I don't think its programmable field stuff is it just discreet components?

I know when I talked to Andreas a few time he felt it necessary to upsample well beyond 64 to get rid of noise when a filter only (dac chipless) approach is employed.

If the PD2 is set to the "direct DSD" mode, it is pretty much the same as chipless. Discrete components on the board do the final low pass filtering just like the GG. If you feed it native DSD, no additional filtering is required. This is because all the filtering was already done at the studio with their ADC/DAW software. You only need to use SRC/SDM filtering for resampling PCM to DSD. This will all be done in my server to quad DSD. Upsampling to quad DSD takes the DSD noise well above the audible range, and sounds by far the best with the PD2.

 

[FlexibleAudio]

Ah..gotcha. Thanks.

 

[Mivera Audio]

Ah..gotcha. Thanks.

No problem. And as far as implementation of the DAC with the quality USB interface, clocking scheme etc, I have gone over that earlier already. Utmost care was used for the lowest jitter and noise possible. Noise isolation from the USB bus, 4 layer PCB board with via stitched dual ground planes, extremely low noise\high PSSR voltage regulators powering every discrete section of the dac board individually. There's even separate regulators feeding each channel of the DAC chip. Sonny came up with a system called "virtual ground" to take noise isolation of the gain stages to a new level as well. With pure DSD, jitter is extremely important. Extreme care must be made to ensure the jitter is very low at the point of being converted to analog. Not just a low jitter clock. The clock signal needs to make it to the chip without adding extra jitter. Simply using a 70 cent clock that comes with the USB interface as the master, doesn't cut the mustard if you want conversion at this level. Keeping the master clock within an inch or 2 of both the USB interface, and the DAC chip is critical.

 

[Mivera Audio]

For folks who already have a very nice preamp, I'll be coming out with a very pure no frills DAC. The Mivera Audio Purestream. It will use the same DAC and output board as the PD2, only it will be just a DAC. For input it will have Ravenna only. And for output, just a simple pair of balanced XLR's. Not even a screen or anything. Just a simple power button. Here's a prototype with USB for an example:

 

[joeinid]

Nice Mike!

 

[Mivera Audio]

Nice Mike!

Thanks Joe! It's a little bit away yet due to optimizing the Ravenna Ethernet interface. But target price will be around $3500. The case will be different from the above case as well. It will be milled from a solid block of aluminum. Combined with the killer server it will be a very attractive package for approx $6000. And it will allow folks with tube preamp's to add that "tube magic" to the sound of Sonny's amazing DAC. "

 

[Geardaddy]

No I am certainly no dealer. I picked this kinda stupid handle a couple of years ago when seeking advice on the best way to do my system for max flexibility. I regret doing so cuz people think I sell stuff but its hard to change once you get going.

Ouch. Okay.

What is your go to source? Vinyl? Why are you sniffing around the Phison tree? MSB falling short in some way? I know your speakers are laser beam accurate. Are you wanting more body and warmth from your digital? What server/software do you use?

How do you like the Torus? There is a thread on Whats Best Forum extolling the virtues of active power filtration, etc....I know that thing must have been a bitch to install. I was looking at the equivalent Equitech product at one point and installation is a pain....

 

[Geardaddy]

Combined with the killer server it will be a very attractive package for approx $6000. And it will allow folks with tube preamp's to add that "tube magic" to the sound of Sonny's amazing DAC. "

Say what? Since when have you become a proponent of "tube magic"? I thought that was for the weak minded? I am sure HQplayer will someday have a nice little DSP that could provide all the fireside warmth/distortion one could desire....:celebrate008_2:

 

[Mivera Audio]

Say what? Since when have you become a proponent of "tube magic"? I thought that was for the weak minded? I am sure HQplayer will someday have a nice little DSP that could provide all the fireside warmth/distortion one could desire....:celebrate008_2:

Everyone has different tastes. And some people already have preamp's they don't want to part with. Of course if a person has no preamp already, or wants to upgrade, the PD2 will be the better choice.

 

[SonnyDK]

I think it is time for me to enter this discussion.

As everyone has found out, my PD2 Preamp DAC section is build around the AK4490. Compared to other DAC chips it has a signal path of the DSD part that is very short just like CS4398, but the chip is newer and laid out for 32Bit + DSD 11.2MHz/PCM768KSamples which is much better than with CS4398.

It uses an internal lowpass filter in conjunction with an external high quality filter with my discrete gain blocks.

Our current implementation supports DSD 11.2MHz and PCM384KSamples (This is limited to the XMOS controller that we use in the moment). Some people has asked why i use only one AK4490. This is due to chip to chip difference. So by using two chips there can be difference in gain from right to left.
Secondly the AK4490 supports two reference voltages for left and right but in most application they use only 1 reference and it is normally RC filteret from a main +5V supply which feeds both analog and digital section.
In my design i have two ultra low noise references, one for each channel to maximize signal separation.

My design will not be found in any other units and also not in the DIY kits i already have made. It will not be released for that. It is fully integrated into the rest of the preamp design and it is not something you can take out. Yes it is module based which makes it possible to upgrade later but it is tightly embedded into the PD2 preamp control firmware.

The newest firmware makes it possible to explore the different signal paths in the DAC "on the fly".

So if you have any questions about the PD2 preamp please ask me and i will answer the best i can.

If you dig into the Review made by Srajan, you will see that my design is unique by using an analog volume control rather than a digital one, as it will not (not at all) degrade the sound heavily when listening at lower volume levels which is the case when using a digital volume control. A french guy pointed out to me that it is rare that he gives such a good reviews on DAC, even when it is tested in PCM only.

BR

Sonny

 

[joeinid]

Welcome to the forum Sonny, thank you for joining.

 

[Geardaddy]

I think it is time for me to enter this discussion.

As everyone has found out, my PD2 Preamp DAC section is build around the AK4490. Compared to other DAC chips it has a signal path of the DSD part that is very short just like CS4398, but the chip is newer and laid out for 32Bit + DSD 11.2MHz/PCM768KSamples which is much better than with CS4398.

It uses an internal lowpass filter in conjunction with an external high quality filter with my discrete gain blocks.

Our current implementation supports DSD 11.2MHz and PCM384KSamples (This is limited to the XMOS controller that we use in the moment). Some people has asked why i use only one AK4490. This is due to chip to chip difference. So by using two chips there can be difference in gain from right to left.
Secondly the AK4490 supports two reference voltages for left and right but in most application they use only 1 reference and it is normally RC filteret from a main +5V supply which feeds both analog and digital section.
In my design i have two ultra low noise references, one for each channel to maximize signal separation.

My design will not be found in any other units and also not in the DIY kits i already have made. It will not be released for that. It is fully integrated into the rest of the preamp design and it is not something you can take out. Yes it is module based which makes it possible to upgrade later but it is tightly embedded into the PD2 preamp control firmware.

The newest firmware makes it possible to explore the different signal paths in the DAC "on the fly".

So if you have any questions about the PD2 preamp please ask me and i will answer the best i can.

If you dig into the Review made by Srajan, you will see that my design is unique by using an analog volume control rather than a digital one, as it will not (not at all) degrade the sound heavily when listening at lower volume levels which is the case when using a digital volume control. A french guy pointed out to me that it is rare that he gives such a good reviews on DAC, even when it is tested in PCM only.

BR

Sonny

Welcome Sonny. So you got tired of all us fools babbling. Educate away. Most audiophiles have some form of attention deficit mixed with unwarranted pride. It will take time to break through. Repeat the information often....:congrats:

And yes, the French guy is correct. Srajan tends to be nitty about dacs unless they are r2r NOS PCM affairs.....get him going on HQPlayer, Roon and a decent streamer (Blizzinator) and give him an appropriate baptism into the world of DSD. I am not sure how computer savvy he is. He did an extensive technobabble preamble piece on the Phasure dac and its software, but it never materialized. Maybe this is the time for him to splash back into the computer domain. Talk to Jussi at HQPlayer. I am sure he would be interested in helping him.....

 

[SonnyDK]

Only Michael is clever than Doofenshmirtz and michaels Blizzinator works!

Yes, but to give a reviewer a solution to test he needs to have something that works nice, or they just stops . No matter who reviews. He did play with HQ player and can hear it adds flavor to it.
Some likes it, others don't.

 

[Geardaddy]

Only Michael is clever than Doofenshmirtz and michaels Blizzinator works!

Yes, but to give a reviewer a solution to test he needs to have something that works nice, or they just stops . No matter who reviews. He did play with HQ player and can hear it adds flavor to it.
Some likes it, others don't.

Well I like Roon/HQplayer into a little Intel NAA with Mike's PS. Sounds nice and Roon as an interface is to die for. Some people have been bitching about its cataloging of classical material but its software so that can be tweaked.....

 

[Mivera Audio]

Only Michael is clever than Doofenshmirtz and michaels Blizzinator works!

Yes, but to give a reviewer a solution to test he needs to have something that works nice, or they just stops . No matter who reviews. He did play with HQ player and can hear it adds flavor to it.
Some likes it, others don't.

What was he using for a computer with HQplayer, and what filters did he use? Did he upsample to quad DSD? If not, I wouldn't recommend it.

 

[SonnyDK]

FYI i am Working on DOP 256. It is nearly there.


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[Mivera Audio]

FYI i am Working on DOP 256. It is nearly there.


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From a MAC? My experience was native sounds better. And with HQplayer, it's much more processor intensive with DoP.

 

[SonnyDK]

Back to the operating system interrupt response! That could be the cause, not the DOP itself.


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