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Review and Measurements of PS Audio PerfectWave DirectStream DAC

amirm

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Wonder if it would measure better if you tested with a DSD stream so it wouldn’t have to do the conversion? They did say that the conversion from PCM to DSD raises the noise floor of an already noisy FPGA.
I don't have good test tones in DSD format. Nor can my analyzer generate them. It is a hole in measurement industry.

As far as I have read, it also upsamaples DSD so it will have to dither anyway.

The noise we are seeing is a combination of analog and digital stages. Unless they can demonstrate it is all from digital stage, in which case their competence is seriously in question with respect to signal processing, I say there is little they can do to impact the noise level of this unit in grand scheme of things. It is short by 30 dB or so to match state-of-the-art DACs. That is a huge, huge gap. Engineers kill for 3 to 6 dB improvement in noise level. 30 dB is an eternity.
 

scott wurcer

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Unless they can demonstrate it is all from digital stage, in which case their competence is seriously in question with respect to signal processing, I say there is little they can do to impact the noise level of this unit in grand scheme of things.
I see obfuscation in the discussion of digital "noise" becoming analog noise. A process like a digital multiply and accumulate has an answer there is not some uncertainty (noise) restricted to the lower bits due to layout/partitioning issues, which would become an analog noise issue. What is published at times preys on the general lack of knowledge of the average user of what is going on.

Digital processing with insufficient length of coefficients or intermediate results properly covered up by dither might result in an analog noise floor when converted back to analog by a DAC.
 

AudioSceptic

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Ha-ha!
I like my tea strong. Very little tea tastes good to me and I had a major search for another I liked when the one I favoured stopped being blended :( now I order it in bulk from a blender in the north of England :) as loose leaves and have teapots with built in strainer so I can remove the leaves when properly brewed. Yum, drinking some as I surf!
Built-in strainer? I'd like one of those so tell me what it is please.
 

Krunok

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Digital processing with insufficient length of coefficients or intermediate results properly covered up by dither might result in an analog noise floor when converted back to analog by a DAC.
.. which is nicely explained in this ESS document on the example of digital volume control processing, but the same principle applies on any other kind of digital processing.
 

Krunok

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I really, really don't like the idea of audio hardware dependent on software updates. A dac has a very simple job to do. Having software updates in a DAC is like having software updates in a shovel.
Every DAC is dependent on software. You can either have updates on the same hardware or you are forced to buy next generation of DAC chip which contains new software (and sometimes better hardware). In that context the idea of software (firmware) updates is actually good. What is bad with this DAC is that crappy transformer in the output stage. And that ridiculous price, of course.
 
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PSAJH

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You need the ratchet straps to tension the package.
I've been experimenting with bungee cords actually. Seems as if the absorption coefficient of the variable tension really helps to dial in my bass. :)
 

g29

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I've been experimenting with bungee cords actually. Seems as if the absorption coefficient of the variable stretch lengths really helps to dial in my bass. :)
I am sure you heard of the old "Amp Clamp" product that would essentially put your audio products into a vice for better sound ?

I actually found a need for a DIY version once. I ran a frequency sweep on my newly remodeled Home Theater/Great room to identify and dampen what ever was resonating at their natural frequencies. Found about 5 things what would sing loudly when the right frequency was hit. One loud noise was coming from the stereo rack. It was the VCR's (before DVD's and BluRays) top plate. I wedged a rubber hockey puck between the top of the VCR and the bottom of the shelf above and resonance was eliminated. Tensioning works I tell you !!!
 

Thomas savage

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I've been experimenting with bungee cords actually. Seems as if the absorption coefficient of the variable tension really helps to dial in my bass. :)
It's definitely worth experimenting with restraints, there's so much joy and pleasure to be had.
 

PSAJH

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I am sure you heard of the old "Amp Clamp" product that would essentially put your audio products into a vice for better sound ?

I actually found a need for a DIY version once. I ran a frequency sweep on my newly remodeled Home Theater/Great room to identify and dampen what ever was resonating at their natural frequencies. Found about 5 things what would sing loudly when the right frequency was hit. One loud noise was coming from the stereo rack. It was the VCR's top plate. I wedged a rubber hockey puck between the top of the VCR and the bottom of the shelf above and resonance was eliminated. Tensioning works I tell you !!!
No kidding, what a solid find!
I'm in a 100+ year old house, and it took me replacing all of the windows in the room to get rid of the rattling.
snatched a rather large chunk out of my hifi budget, but well worth it!
 

Frank Dernie

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g29

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No kidding, what a solid find!
I'm in a 100+ year old house, and it took me replacing all of the windows in the room to get rid of the rattling.
snatched a rather large chunk out of my hifi budget, but well worth it!
I had just gutted and remodeled a house built in the 1920's. Not quite 100 years, but it still had plenty of issues to correct. If memory serves, the window treatments were also an issue and surprisingly the plastic shroud covering the back of a Mitsubishi 35" picture tube television got really loud at it's resonant frequency. Some Dynamat Extreme would have helped the TV shroud, but those dampening products weren't around then.
 

GrimSurfer

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You'll need to prove it with a double-blind ABX.
Or tell us that it has a firmware update...

Yeah. Software. That'll fix all life's problems.
 
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