[flyte3333]

No, it's not. Most people don't understand even the slightest thing about measurements.

Please read the rest of my post for extra context showing it is a very reasonable query. Also see the published info from other Pro DACs included above also...

And once again, it was a polite and very reasonable question directed to iFi... Crikey...

 

[iFi audio]

Can you kindly advise why there aren't any distortion figures published for Pro iDSD? Channel separation / crosstalk figures? Headphone output impedance? SNR? THD? IMD?

As you're aware, Pro iDSD is a features packed machine; DSD remastering, upsampling, three different operational hardware modes etc. It depends on what one measures of course, but each change gives different results. There are hundreds of options possible and each with its own set of measurements. So Pro iDSD in numbers would be a book, not a leaflet

 

[audiocraze]

As you're aware, Pro iDSD is a features packed machine; DSD remastering, upsampling, three different operational hardware modes etc. It depends on what one measures of course, but each change gives different results. There are hundreds of options possible and each with its own set of measurements. So Pro iDSD in numbers would be a book, not a leaflet

Then why don’t you publish the book? After all, you tested and measured it all already, right? Nothing to hide I’m sure.

 

[gordec]

I'm still on firmware 1.55 beta. Which new firmwares should I update to? There is still nothing on the official Pro iDSD website.

 

[flyte3333]

Just seen Stereophile's review of the Pro iDSD (subscription), including JA's measurements

JA's final comments included: I remain puzzled by the rise in HF noise floor in BP and BP+ and low level spuriae in the Pro iDSD's output.

The review and measurements should make it to Stereophile website in the next week or so.

Herb's subjective listening impressions review was very positive.

 

[audiocraze]

Also, I found that the tube and tube+ modes add lots of hiss and distortion. If upsampling / filters are not engaged, lots of hiss is audible. And the headphone amp has such a low output that I can only assume this is on purpose to make buyers add the pro ican. Even the micro idsd has more output and can drive headphones better. Why’s that?

A while ago I made these statements but ifi chose to ignore. Instead they hastily brought out a “beta MQA” software version that, with hindside, they should have kept a little longer in development, judging by the issues reported here.. I still find it quite annoying to bring out an unusable headphone output at 3ohm. Where’s the PRO STATUS in there? Even IEMs have more impedance, let alone any pro-level studio headphone. Trying to sell Pro-stacks by adding useless features that frustrate is not wise.

 

[flyte3333]

JA also notes poor ultrasonic noise rejection. I wonder if this is RF internally generated by the noisy DSP (FPGA and XMOS DSP)...

He also says that when he turned on Pro iDSD, it blocked FM reception of a portable radio in his lab...

 

[flyte3333]

@iFi audio , a feature request for the v2.0 firmware: if the user is not using the Network input, can you please have the WiFi radio powered off?

The WiFi radio should only need to be enabled when the Network input is selected by the user.

I don't use the Pro iDSD's WiFi but it's somehow causing interferences with bluetooth devices nearby... Even with the antenna not installed, Pro iDSD's WiFi signal is at full strength for quite a distance....

 

[youurayy]

@iFi audio , a feature request for the v2.0 firmware: if the user is not using the Network input, can you please have the WiFi radio powered off?

The WiFi radio should only need to be enabled when the Network input is selected by the user.

I don't use the Pro iDSD's WiFi but it's somehow causing interferences with bluetooth devices nearby... Even with the antenna not installed, Pro iDSD's WiFi signal is at full strength for quite a distance....

+1000

 

[applesnowleo]

Turnig off the WI-FI is something I asked on some forums and never had feedback.

Yes thats a logical feature to have, maybe more on the computer side than on an audio device, but I also would like to have it here, it could be that the way is implemented this could not be done, but if it can be done is something that should be present if not on the 2.0 firmware, at least on the roadmap for a future one.

 

[iFi audio]

Turnig off the WI-FI is something I asked on some forums and never had feedback.

Yes thats a logical feature to have, maybe more on the computer side than on an audio device, but I also would like to have it here, it could be that the way is implemented this could not be done, but if it can be done is something that should be present if not on the 2.0 firmware, at least on the roadmap for a future one.

We'll pass this on to our R&D team.

 

[iFi audio]

Just seen Stereophile's review of the Pro iDSD (subscription), including JA's measurements

JA's final comments included: I remain puzzled by the rise in HF noise floor in BP and BP+ and low level spuriae in the Pro iDSD's output.

The review and measurements should make it to Stereophile website in the next week or so.

Herb's subjective listening impressions review was very positive.

To make it on time for EISA judges, we had to hurry. That's why the machine the Stereophile team got (and each EISA judge as well) had beta FW applied.

 

[flyte3333]

+1000

I've seen multiple people ask for this, here and on CA Forum.

Should be simple to turn off the WiFi radio, if the Network input is NOT selected / used.

To make it on time for EISA judges, we had to hurry. That's why the machine the Stereophile team got (and each EISA judge as well) had beta FW applied.

Perhaps a good time then for Thorsten to consider showing plots with the v1.6 firmware? To counter balance with Stereophile’s measurements with v2.0 beta?

Just for consideration...

And how does the v2.0 beta affect the ultrasonic noise filtering that JA commented about?

 

[gordec]

All the complaining aside. Pro iDSD sounds amazing. I have it powered by Uptone JS2 LPS. You squeeze more detail and dynamics out off it.

 

[flyte3333]

All the complaining aside. Pro iDSD sounds amazing. I have it powered by Uptone JS2 LPS. You squeeze more detail and dynamics out off it.

Agreed - sounds great. I feed Pro iDSD DSD512 via HQPlayer, by-passing all of Pro iDSD's internal DSP... All digital filtering is done before Pro iDSD so in this case, Pro iDSD only does the conversion to analogue (the DSD1793's..) and then there is the output stage's analogue filtering.

Pro iDSD is quite a step up from the micro iDSD BL (to my ears and tastes) which was already a great performer.

Sometimes polite and respectful technical queries on forums can get wrongly mis-interpreted as 'complaining'...

They are nothing more than technical queries - @iFi audio used to answer all these queries in great detail in the past (Head-Fi and CA Forum and other places) so I hope it continues... Their transparency in the past was always much welcomed, so I hope that continues...

Companies are becoming more and more transparent - not less. Just look at Ted Smith on PSA's forum answering all technical queries and sharing whatever plots you could want, Rob Watts doing the same on Chord threads, RME doing the same on their forum, Andrew Mason of THX doing the same for Massdrop THX 789 amp, Benchmark's John Siau answering technical queries here on Head-Fi too... Just some examples...

So hopefully the R&D group can shed some light on my earlier queries about Stereophile's measurements and maybe share some plots to counter JA's results... Especially since we are now talking about the Pro world with Pro iDSD...