[SptTablo]

I just took a look at iFi's website. Does the iDSD (either Micro or Nano) play true DSD audio? By true I mean 1-bit decoding as opposed to typical ESS applications of "DSD support" with multi-bit Delta Sigma modulation.

The iFi nano iDSD is full of ‘firsts.’ It is the world’s smallest, portable (only 163g), battery-powered, serious DAC that plays ALL high-resolution formats: PCM/DSD/DXD natively.
 
This is directly from IFI's website on Nano iDSD. I assume that they do. 

 

[miceblue]

This is directly from IFI's website on Nano iDSD. I assume that they do. 

That's an assumption though. : p

From OPPO's website
https://www.oppodigital.com/headphone-amplifier-ha-2/headphone-amplifier-HA-2-Features.aspx

Input Format Stereo PCM, Stereo DSD (DoP v1.1 or native)

Native in this case means DSD data from source is transferred as DSD data to the DAC. DSD over PCM (DoP) isn't considered native in this case because in order for DSD data to be transferred to the DAC in Mac OS X, the DSD data has to be wrapped/disguised as a PCM signal (NOT the same as converting to PCM mind you).

So I'm wondering if iFi meant this kind of "native" DSD playback or true 1-bit DSD playback.

 

[ClieOS]

I just took a look at iFi's website. Does the iDSD (either Micro or Nano) play true DSD audio? By true I mean 1-bit decoding as opposed to typical ESS applications of "DSD support" with multi-bit Delta Sigma modulation.

 
Actually Delta-Sigma modulation is what needed to decode DSD. The only difference is that you only need 1 bit for DSD as opposed to multi-bit for PCM audio. To answer your question: yes, iDSD nano and micro both perform native DSD decoding up to the hardware level, with no internal DSD-PCM conversion of any kind.

 

[miceblue]

Actually Delta-Sigma modulation is what needed to decode DSD. The only difference is that you only need 1 bit for DSD as opposed to multi-bit for PCM audio. To answer your question: yes, iDSD nano and micro both perform native DSD decoding up to the hardware level, with no internal DSD-PCM conversion of any kind.

Er, yeah that was poor wording on my part.
DSD == 1-bit Delta-Sigma modulation

ESS Sabre DACs use multi-bit DS modulation regardless of the input signal, from what I understand. There's no way you can have digital volume control (a feature of ESS DACs and what the HA-2 uses) with a 1-bit signal, so the ESS DACs employ multi-bit signal processing. This is also not the same as converting DSD audio to PCM. As mentioned in my previous post too, DSD over PCM is not converting DSD data into PCM either.


I guess what I had meant to ask was if the Burr Brown chips used in the iDSD products use 1-bit, not multi-bit, DS modulation to decode 1-bit DSD data as a true DSD DAC similar to the PS Audio DirectStream DAC (except that converts PCM audio to DSD).

 

[SptTablo]

Thanks for correcting me. 
 
I love learning new things

 

[ClieOS]

Er, yeah that was poor wording on my part.
DSD == 1-bit Delta-Sigma modulation

ESS Sabre DACs use multi-bit DS modulation regardless of the input signal, from what I understand. There's no way you can have digital volume control (a feature of ESS DACs and what the HA-2 uses) with a 1-bit signal, so the ESS DACs employ multi-bit signal processing. This is also not the same as converting DSD audio to PCM. As mentioned in my previous post too, DSD over PCM is not converting DSD data into PCM either.


I guess what I had meant to ask was if the Burr Brown chips used in the iDSD products use 1-bit, not multi-bit, DS modulation to decode 1-bit DSD data as a true DSD DAC similar to the PS Audio DirectStream DAC (except that converts PCM audio to DSD).

 
Yes, it is 1 bit DSD decoding on both iDSD nano and micro, and thus why neither of them has any digital volume control. The volume control on nano is actually digital-over-analog (that is, an ADC senses the position of the pot, then digitally set the resistor array in a chip for volume control) where it is just good old fashion pot in micro. Both are done after the DAC stage, in the analog domain.
 
On the other hand, technically you still need DoP for both nano and micro for DSD playback. But DoP is just a way to 'trick' the computer in sending data inside a wrapper, it doesn't in anyway alter the content and therefore it is still considered native, on the 1 and 0 level.

 

[SptTablo]

  Just sat down and gave both iDSD nano and HA-2 a comparison - using both as pure DAC and feeding the line-out to a FiiO E12DIY driving DUNU DN-2000, I'll say the performance is roughly equal. Nano sounds more organic (especially with Minimum Phase filter) where HA-2 sounds more transparent (or digital, if you like. It's an ESS characteristic no doubt). When used as amp+DAC however, I do feel that HA-2 has a slight edge over nano, namely it offers slightly better control and power, as well as a bigger image. Nano's image isn't bad either, but it is smaller in comparison. The upside is that nano is, again, sounding more organic than HA-2.
 
If it is going to be used as mainly a DAC, I think nano makes for a better choice as it is cheaper and about just as good as HA-2 on the line-out. But HA-2 is more proficient as an all-in-one choice, plus the size is just right.

One question for you!
 
How do you use the line-out function on ifi Nano iDSD?
 
It seems like it lacks a port. 

 

[miceblue]

Yes, it is 1 bit DSD decoding on both iDSD nano and micro, and thus why neither of them has any digital volume control. The volume control on nano is actually digital-over-analog (that is, an ADC senses the position of the pot, then digitally set the resistor array in a chip for volume control) where it is just good old fashion pot in micro. Both are done after the DAC stage, in the analog domain.

On the other hand, technically you still need DoP for both nano and micro for DSD playback. But DoP is just a way to 'trick' the computer in sending data inside a wrapper, it doesn't in anyway alter the content and therefore it is still considered native, on the 1 and 0 level.

Ah okay. That's good to know! Thanks for clarifying that.

Digitally-controlled analogue volume sounds a lot like the JDS Labs C5.

 

[gixxerwimp]

 

SptTablo /img/forum/go_quote.gif
  How do you use the line-out function on ifi Nano iDSD?
 
It seems like it lacks a port. 

 
Looks like it has 2 RCA line-out jacks.

Quote: http://ifi-audio.com/portfolio-view/nano-idsd/

Output	SPDIF RCA (only PCM up to 192KHz)
	Audio RCA

 
[Edit: also found these]
 
http://ifi-audio.com/portfolio-view/android/#level3
Not sure why the diagram shows a 3.5mm-to-3.5mm cable, since the 3.5mm output of the nano is a headphone output.
 
Also this example with an iCAN: http://www.head-fi.org/t/683406/ifi-audio-nano-idsd-discussion-impression#post_9900244

 

[Sikedaman]

Ordered mine off Oppodigital while they were on back order with an estimated availability date of 3/20, checked in today and they are hoping to get them in stock by early next week. Looks like another week of waiting.

 

[gerelmx1986]

but all the iDSD are ugly... the oppo is sexy and slim

 

[ClieOS]

Ah okay. That's good to know! Thanks for clarifying that.

Digitally-controlled analogue volume sounds a lot like the JDS Labs C5.

 
Yes, though there is dedicated 'digital pot' in C5 where the volume control in nano is already integrated inside the headphone driving chip.
 

  One question for you!
 
How do you use the line-out function on ifi Nano iDSD?
 
It seems like it lacks a port. 

 
 

   
Looks like it has 2 RCA line-out jacks.

 
Those RCA becomes the line-out when you max out the volume pot. The chip that drives headphone-out is doing a double duty. It is an headphone amp but also can acted as a buffer for the DAC. When you turn the pot to max, the chip disable the volume control function and acting as a buffer stage for the DAC and output to the RCA.
 

  but all the iDSD are ugly... the oppo is sexy and slim

 
If only that has anything to do with audio performance, or picking one to marry...

 

 

[SptTablo]

   
Yes, though there is dedicated 'digital pot' in C5 where the volume control in nano is already integrated inside the headphone driving chip.
 
 
 
 
Those RCA becomes the line-out when you max out the volume pot. The chip that drives headphone-out is doing a double duty. It is an headphone amp but also can acted as a buffer for the DAC. When you turn the pot to max, the chip disable the volume control function and acting as a buffer stage for the DAC and output to the RCA.
 
 
If only that has anything to do with audio performance, or picking one to marry...

 

How about the headphone out?
 
Does it become line-out as well?
 
And how's their driving power?
 
I probably should ask this to nano idsd thread... 
 
sorry

 

[ClieOS]

  How about the headphone out?
 
Does it become line-out as well?
 
And how's their driving power?
 
I probably should ask this to nano idsd thread... 
 
sorry

 
You are right, these question were better asked over at the nano thread so this is the last answer: Yes, you can use the 3.5mm as line-out as well, as it is internally linked to the RCA. I wrote a review on the nano in the forum, you might want to read it here.
 
Now lets go back to the regular program.

 

[SptTablo]

   
You are right, these question were better asked over at the nano thread so this is the last answer: Yes, you can use the 3.5mm as line-out as well, as it is internally linked to the RCA. I wrote a review on the nano in the forum, you might want to read it here.
 
Now lets go back to the regular program.

Thank you for your kind helps and replies
 
I think I am going to get nano idsd. 
 
Thanks again and sorry for off tracking the thread.