I'm surprised you find iDSD not up to par. I like it and its DSD performance is great. My friend who owned a DAC which is 10X iDSD price commented that it's value-for-money. We tested it with LCD-3, HD650, Fidelio X1, AKG650, and many other HP, all sounded fine.
Headphone Reviews and Discussion - Head-Fi.org
hk6230
StratocasterMan
I bought an iDSD and had to return it. I have a very late-model computer running Windows 8.1 that only has USB 3.0 ports and no USB 2.0 ports. The driver for the iDSD did not work. It wouldn't play anything above 44.1 kHZ / 16 bit. I was disappointed that the iDSD simply didn't have a compatible driver for my Lenovo PC. For a product that is touted as having the latest features, it should have a driver that works with the latest PCs.
fcaton
Hi,
Thanks for an interesting review.
I can't comment on the sound as I don't have any of the two you compare. Also, I don't know from your review on what setup you made the comparison for sound evaluation.
However I am quite surprised by your measurements and your interpretation:
1) the frequency response you measure is clearly with the minimum phase filter, not the normal one (see CliOS measurements in the other review). With the normal filter, and using CliOS measurements, the frequency response is at least as good as that of the ODAC, and probably a bit better, not that it matters.
2) noise levels, dynamic range are the same, quite clearly limited by your tools, THD is marginally worse with the ifi (still in the -90dB and probably due to your choice of filter BTW...)
3) Most importantly, the IMD is huge with the ODAC: -20dB at 8kHz!!! This is quite shocking.
Any idea where this atrocious IMD comes from?
Thanks for an interesting review.
I can't comment on the sound as I don't have any of the two you compare. Also, I don't know from your review on what setup you made the comparison for sound evaluation.
However I am quite surprised by your measurements and your interpretation:
1) the frequency response you measure is clearly with the minimum phase filter, not the normal one (see CliOS measurements in the other review). With the normal filter, and using CliOS measurements, the frequency response is at least as good as that of the ODAC, and probably a bit better, not that it matters.
2) noise levels, dynamic range are the same, quite clearly limited by your tools, THD is marginally worse with the ifi (still in the -90dB and probably due to your choice of filter BTW...)
3) Most importantly, the IMD is huge with the ODAC: -20dB at 8kHz!!! This is quite shocking.
Any idea where this atrocious IMD comes from?
elmura
fcaton - Your interpretation of the IMD graph is incorrect. This IMD test has two pulses, one @ 60Hz -5dB, other @ 7kHz -17dB.
Also, with Standard Filter, ODAC still has superior Frequency Response. I've just added some measurements I did previously: https://dl.dropboxusercontent.com/u/90236454/iFi%20iDSD%20Nano%20vs%20ODAC.pdf
All measurements with iFi were worse including ones I didn't post. I posted results with Min Phase as that is the one most people listen to because they believe it to be 'natural'. The measurement legend specifies that I used Min Phase and Internal Battery Power for theoretically superior sound.
Also, with Standard Filter, ODAC still has superior Frequency Response. I've just added some measurements I did previously: https://dl.dropboxusercontent.com/u/90236454/iFi%20iDSD%20Nano%20vs%20ODAC.pdf
All measurements with iFi were worse including ones I didn't post. I posted results with Min Phase as that is the one most people listen to because they believe it to be 'natural'. The measurement legend specifies that I used Min Phase and Internal Battery Power for theoretically superior sound.
fcaton
Hi elmura,
Thanks for the measurements, but there is something wrong here. This is the frequency response measured by ClieOS:
http://i90.photobucket.com/albums/k240/ofey_s/iFi/SpectrumiDSDnano.png
It's ruler flat down from 100Hz to less than 20Hz while your measurement shows a clear dip. The same is true for the high frequency response above 15kHz.
Maybe you are measuring a sample that is not up to specs. But I also have to say that I can't help but find your swept measurements results very poor for both dacs.
Cheers.
Thanks for the measurements, but there is something wrong here. This is the frequency response measured by ClieOS:
http://i90.photobucket.com/albums/k240/ofey_s/iFi/SpectrumiDSDnano.png
It's ruler flat down from 100Hz to less than 20Hz while your measurement shows a clear dip. The same is true for the high frequency response above 15kHz.
Maybe you are measuring a sample that is not up to specs. But I also have to say that I can't help but find your swept measurements results very poor for both dacs.
Cheers.
elmura
Fcaton,
It is true that different measuring systems and setups will produce differing absolute results. What's more important, is the relative difference within the same setup. All my comparisons whether from laptop as source, Samsung S3 as source or PC as source; With Min Phase or Standard Filter; unloaded or loaded; headphone out or RCA out... all showed the same relative difference.
ie. The iFi iDSD Nano measures somewhat worse than the ODAC pretty much across the board.
It is true that different measuring systems and setups will produce differing absolute results. What's more important, is the relative difference within the same setup. All my comparisons whether from laptop as source, Samsung S3 as source or PC as source; With Min Phase or Standard Filter; unloaded or loaded; headphone out or RCA out... all showed the same relative difference.
ie. The iFi iDSD Nano measures somewhat worse than the ODAC pretty much across the board.
fcaton
Hi Elmura,
First of all thanks again for you efforts, they're really appreciated: found for thought. I am not convinced by your "relative measurements" argument and least of all by the swept measurements. You should have found the proper frequency response, and I suspect that your sound card improves ODAC measurement as it should be -0.4 dB at 20kHz (http://nwavguy.blogspot.fr/2012/04/odac-released.html).
That said, I've done a bit more research, and I have seen measurements similar to yours, worse and better. Interestingly, your original measurements are coherent with the one made by iFi:
http://ifi-audio.com/audio_blog/does-the-nano-idsd-measure-good-bad-or-ugly/
Discarding your frequency response measurement which is clearly incorrect, you find the same THD+N spectrum with the first harmonic about -90dB. Its clearly not as good as the ODAC, but the ODAC is the best measuring DAC in this respect out there. Other measurements are identical for both dacs. So, qualifying the IDSD as sub-par because of that is a bit, how to say, too much? As is to say that the ODAC clearly outperformed the IDSD.
This is even more pertinent since there is one measurement (that you cannot perform) in which the iFi IDSD vastly outperforms the ODA: jitter.
ODAc measurement: http://nwavguy.blogspot.fr/2012/04/odac-released.html
IDSD measurement: http://ifi-audio.com/wp-content/uploads/2014/08/09-iDSD-nano-J-Test-44.1K-16Bit-1024x511.jpg
(from here: http://ifi-audio.com/audio_blog/does-the-nano-idsd-measure-good-bad-or-ugly/)
Note that the iFi vertical scale is from -70 to -150dB, while the ODAC is 0DB to 150dB therefore favoring the ODAC....
The true jitter of IDSD appears to be below the resolving power of the measurement instrument.
One last question: when you speak about sound evaluation, what headphones did you use?
Thanks again,
F.
First of all thanks again for you efforts, they're really appreciated: found for thought. I am not convinced by your "relative measurements" argument and least of all by the swept measurements. You should have found the proper frequency response, and I suspect that your sound card improves ODAC measurement as it should be -0.4 dB at 20kHz (http://nwavguy.blogspot.fr/2012/04/odac-released.html).
That said, I've done a bit more research, and I have seen measurements similar to yours, worse and better. Interestingly, your original measurements are coherent with the one made by iFi:
http://ifi-audio.com/audio_blog/does-the-nano-idsd-measure-good-bad-or-ugly/
Discarding your frequency response measurement which is clearly incorrect, you find the same THD+N spectrum with the first harmonic about -90dB. Its clearly not as good as the ODAC, but the ODAC is the best measuring DAC in this respect out there. Other measurements are identical for both dacs. So, qualifying the IDSD as sub-par because of that is a bit, how to say, too much? As is to say that the ODAC clearly outperformed the IDSD.
This is even more pertinent since there is one measurement (that you cannot perform) in which the iFi IDSD vastly outperforms the ODA: jitter.
ODAc measurement: http://nwavguy.blogspot.fr/2012/04/odac-released.html
IDSD measurement: http://ifi-audio.com/wp-content/uploads/2014/08/09-iDSD-nano-J-Test-44.1K-16Bit-1024x511.jpg
(from here: http://ifi-audio.com/audio_blog/does-the-nano-idsd-measure-good-bad-or-ugly/)
Note that the iFi vertical scale is from -70 to -150dB, while the ODAC is 0DB to 150dB therefore favoring the ODAC....
The true jitter of IDSD appears to be below the resolving power of the measurement instrument.
One last question: when you speak about sound evaluation, what headphones did you use?
Thanks again,
F.
elmura
Fcaton - you seem to have an agenda. That or strong bias.
How is the iFi Jitter "vastly" better than ODAC and "below the resolving power of the measurement instrument"???
Firstly the ODAC was measured with 24-bit data hence showing a lower noise floor that uncovers ultra low level spuria under -130dB with peak Jitter of -117dB. The iFi was measured with 16-bit data with a noise floor masking up to -130dB and having a peak of -122dB. Better? Yes. At this ultra low level, almost insignifanct.
"Discarding your frequency response which is clearly incorrect" and "I suspect that your sound card improves ODAC measurement" -- An EMU 0204 USB was used to perform the comparative measurements. The ONLY change was the DAC. I ran multiple different measurement setups in a purely comparative manner. Indeed, one setup showed the ODAC being -0.36dB @ 20kHz. In that same test, at 20Hz, the iFi was 1dB lower, and 2dB lower at 10Hz.
The THD Swept -15dB graph shows the iFi being 11dB worse at 8kHz. The -6dB graph shows a massive 24dB worse distortion by the iFi.
I think you are trying to imply that grass is not green.
Sound evaluation was via an external buffer amp into a Audeze LCD-2 r2. Internal amp of iFi was worse.
How is the iFi Jitter "vastly" better than ODAC and "below the resolving power of the measurement instrument"???
Firstly the ODAC was measured with 24-bit data hence showing a lower noise floor that uncovers ultra low level spuria under -130dB with peak Jitter of -117dB. The iFi was measured with 16-bit data with a noise floor masking up to -130dB and having a peak of -122dB. Better? Yes. At this ultra low level, almost insignifanct.
"Discarding your frequency response which is clearly incorrect" and "I suspect that your sound card improves ODAC measurement" -- An EMU 0204 USB was used to perform the comparative measurements. The ONLY change was the DAC. I ran multiple different measurement setups in a purely comparative manner. Indeed, one setup showed the ODAC being -0.36dB @ 20kHz. In that same test, at 20Hz, the iFi was 1dB lower, and 2dB lower at 10Hz.
The THD Swept -15dB graph shows the iFi being 11dB worse at 8kHz. The -6dB graph shows a massive 24dB worse distortion by the iFi.
I think you are trying to imply that grass is not green.
Sound evaluation was via an external buffer amp into a Audeze LCD-2 r2. Internal amp of iFi was worse.
