FPGA improvements in Redcloud


#91

See, http://www.psaudio.com/ps_faq/sd-card-questions/


#92

Thanks Ted. I’ll give it a shot. It’s hard to find - I believe it’s the 2gb or 4gb cards these days.

Thanks elk!! :slight_smile:


#93

timm,

I’ve been using 8 GB cards and they work just fine. I believe that 16 and 32 MB cards also work as well.


#94

Newegg.com has dozens of 2 or 4 gb SD cards for as low as $6 with free shipping. Amazon usually has the same ones.


#95
Ted Smith said

Steady state or averaged measurements don’t really show the problem in earlier releases - arguably if steady state measurements showed it we would have fixed it long ago. With Redcloud the noise floor is very flat over the audio frequencies (up to about 70, 80 or 90kHz) and doesn’t depend on the signal - there aren’t any spurs to be found. There’s a little low level THD like in any DAC, but it’s lower than it used to be. There’s also a little less THD distortion in the lower frequencies. The differences between Redcloud and Huron in the bass will be similar to the differences between Huron and Torreys in the bass. It’s hard to describe how things solidify when the bass is better time aligned with every thing else, but it makes a noticeable difference over the whole audio frequency range. I do hope we can get JA to redo his Stereophile measurements, but I don’t know if that’s in the works or not.


Ted, in JA’s Stereophile review he also estimated that the DirectStream DAC had 17 bit resolution. Do you concur? Am I correct in assuming whatever the sound quality improvements in Redcloud, the DirectStream DAC resolution itself is unaffected?

Also, are all of the original samples preserved through final signal output or are they destroyed in the upsampling process? If the original sample are not preserved, is there any concerns over this musical accuracy-wise?


#96
htpc said

Ted, in JA’s Stereophile review he also estimated that the DirectStream DAC had 17 bit resolution. Do you concur? Am I correct in assuming whatever the sound quality improvements in Redcloud, the DirectStream DAC resolution itself is unaffected?

Also, are all of the original samples preserved through final signal output or are they destroyed in the upsampling process? If the original sample are not preserved, is there any concerns over this musical accuracy-wise?

Many of his measurements are obscured by the noise inherent in single bit DSD DACs. (See for example his complaints when measuring the well regarded Playback Designs MPS-5 https://www.stereophile.com/content/playback-designs-mps-5-sacdcd-player-measurements)

There’s also a difference between resolution and noise floor. Resolution is the least difference on the input that has the proper change in the output. Ironically JA later complains about the non-linearity at -120dBFS - if the resolution was indeed only around 102dB (17 bits) how was he be measuring changes in the output caused by a signal with fewer than 20 bits (-120dBFS)? (That non-linearity was improved with in later releases of DS software, some of which JA also reports on.)

Perhaps thinking of dither would help illustrate this - dither increases resolution at the expense of raising the noise floor. Using dither 16 bits can achieve more than the otherwise expected 96dBFS resolution but the noise floor is then raised above the otherwise expected -96dBFS.

Releases since his original measurements have lowered both the digital noise floor and the analog noise floor over the audio range and lowered the ultrasonic noise even more.

This is in part why I’d like to see new measurements from John: With Redcloud he would see better resolution and better low level linearity (a -96 or -120dBFS signal doesn’t have any of the distortions apparent in his earlier measurements.)

Not only are all inputs bits preserved, they are preserved at any volume setting. The minimum (non mute) volume setting is one which represents -49.5dBFS. Measuring the effect of changing one lower level input bit with the volume set to -49.5dBFS takes a lot of time (you need to do FFTs with a lot of buckets and average many of them together.)

The advantage of single bit DSD is that with a single bit there is inherent linearity (two points define a line) unlike PCM implementations which often loose linearity long before their noise floors.

In essence Redcloud fixes a long standing bug in the signal processing in the FPGA that disrupted the inherent linearity of single bit DSD.


#97

Newegg.com has dozens of 2 or 4 gb SD cards for as low as $6 with free shipping. Amazon usually has the same ones.”

Look in the checkout line at your local grocery store - small USB sticks are everywhere these days.


#98

When is Redcloud actually coming? I thought it was supposed today.


#99

It was. We get waylaid. Sorry. Next week, for sure. We also have the new Bridge II code finished with all the new features… stay tuned. It’ll be huge.


#100

Thank you…


#101

What new features are going to be there in the new code for bridgeII please? Intriguing! :slight_smile:


#102

(next to Tidal) enabling of the integrated streaming services Qobuz, Spotify, Deezer and vTuner would be very nice…!?!


#103

Very much looking forward to see what comes in this release as my first experience of new firmware with PSA.


#104

Paul

Can we expect SQ improvement with the new Bridge 11 firmware?

magicknow


#105

The Bridge update will be detailed next week as well. While there are no sonic improvements expected there are some bugs that have been fixed as well as features added. Spotify Connect, Vtuner, Quboz, among them. Stay tuned.


#106

DMP-like display as well? :wink:


#107

Paul McGowan said

The Bridge update will be detailed next week as well. While there are no sonic improvements expected there are some bugs that have been fixed as well as features added. Spotify Connect, Vtuner, Quboz, among them. Stay tuned.

Spotify Connect…circle-of-hearts-smiley-emoticon_gif


#108

Paul that is huge on the added features to the BridgeII…thank you thank you


#109

How will all of these new Bridge features be controlled? Is Roon coming out with integration or PSA going to have a separate app?


#110

Spotify Connect will work with the Spotify app -= the Bridge will then show up as one of the devices on your home network you can play to.

The other new services will be available through the MConnect app.