[bluesaint]

@iFi audio I ordered and waiting for mine to come in (this week). Quick question, as I have iCAN Pro as well, Is there a suggested mode to connect the two? ie. If i'm listening on Tube mode on iCan, should i set the iDSD Pro in Tube mode as well? What about gain? Basically trying to understand the balance/synergy when pairing the 2 together.

@iFi audio would you mind responding?

 

[hop ham]

I got a defective unit, sigh, now I have to wait for dealer to get an answer from iFi on how long it will take to get a replacement. After such a long wait this is a bummer but I understand things like this happen. I'm gonna give this another shot.

 

[MLGrado]

• filters can be selected for DSD and PCM up to 192KHz

44.1 - 192KHz

• Additional fixed second order analogue filter @ 80kHz

DSD Filters:

• Four different filters (selectable) with varying bandwidth
• Additional fixed second order analogue filter @ 80kHz

The other resources (website etc.) only list for DSD filter a third order analog 80 khz cutoff with 6 db compensation for DSD level.

No mention of the usual four Burr Brown 8 tap FIR filter choices til I saw it here, so I was confused. So the implementation is like previous iFi products for DSD. Selectable FIR filter, with fixed filter following. (This fixed filter is in place for all formats, PCM included)

My only confusion now is the actual order of the filter (second or third), and how the 6db compensation is applied to DSD only and not the PCM formats?

 

[iFi audio]

@iFi audio would you mind responding?

It's simple. If you use balanced headphone out, then connect both devices via XLRs. If you use i.e. 6.3mm out, then go for RCAs.

I got a defective unit, sigh, now I have to wait for dealer to get an answer from iFi on how long it will take to get a replacement. After such a long wait this is a bummer but I understand things like this happen. I'm gonna give this another shot.

We're sorry to hear that. Hopefully it'll work out soon. If not, please do let us know here via PM. Thanks!

 

[iFi audio]

The other resources (website etc.) only list for DSD filter a third order analog 80 khz cutoff with 6 db compensation for DSD level. No mention of the usual four Burr Brown 8 tap FIR filter choices til I saw it here, so I was confused.

This is correct. DSD does use a fixed 8-tap analogue FIR filter followed by a passive 3rd order LCR lowpass at 80kHz. The FIR filter was selected for best rejection of ultrasonic noise while allowing full bandwidth.

So the implementation is like previous iFi products for DSD. Selectable FIR filter, with fixed filter following.

It is NOT like previous products.

All digital filters are implemented in our new Chrysopeia FPGA based DSP engine, allowing us a wide range of filters IF upsampling (PCM or DSD) is enabled.

It is also possible to completely bypass the Chrysopeia FPGA and to send non-oversampled PCM and DSD directly to the DAC, operating without digital filter for PCM or the aforementioned 8-tap analogue FIR for DSD.

(This fixed filter is in place for all formats, PCM included)

Correct. It is a necessary low-pass to remove ultrasonic noise far beyond the audio range. We use a passive LC (inductor/capacitor) filter that offers its maximum attenuation of ultrasonic noise at around 6MHz and remains effective to beyond 75MHz. In the traditional sense of the word it's not a 'reconstruction filter'.

My only confusion now is the actual order of the filter (second or third), and how the 6db compensation is applied to DSD only and not the PCM formats?

It is a 3rd order filter (60dB per decade - so 800kHz are attenuated by around 60dB).

As DSD uses a '0dBFS' setting of 50% modulation, DSD is normally 6dB quieter than a PCM version of exactly the same master as for PCM we have a '0dBFS' setting of 100% modulation.

The gain compensation add 6dB extra gain for DSD and thus removes the actual and perceived level differences.

 

[MLGrado]

This is correct. DSD does use a fixed 8-tap analogue FIR filter followed by a passive 3rd order LCR lowpass at 80kHz. The FIR filter was selected for best rejection of ultrasonic noise while allowing full bandwidth.

It is NOT like previous products.

All digital filters are implemented in our new Chrysopeia FPGA based DSP engine, allowing us a wide range of filters IF upsampling (PCM or DSD) is enabled.

It is also possible to completely bypass the Chrysopeia FPGA and to send non-oversampled PCM and DSD directly to the DAC, operating without digital filter for PCM or the aforementioned 8-tap analogue FIR for DSD.

Thank you. That clarifies exactly what I was asking. When I said it was like previous implementations, I was only referring to the general architecture for DSD when using 'Direct' mode. The unaltered bitstream goes to the FIR filter like in previous products for conversion, with a second fixed filter to follow. But if now the FIR filter is set at a fixed setting, then in that sense it is also NOT like previous products.

Sorry for the confusion!

Thanks so much!

 

[Dr. Manhattan]

TRIFECTA!!!

 

[alphanumerix1]

very nice indeed.

 

[MLGrado]

I just want to leave a short note of thanks for you guys at iFi. I have pestered a few of you for years about this day, and it has arrived, what I consider the ultimate DSD solution currently available on the market. It truly is a 'have it your way' solution.

If you want DSP processed DSD, you get it. If you want untouched pure DSD with the only conversion element being the final analogue filter, you get it. ( well, as pure as DSD gets in all practicality. One could conceivably use a one bit switch, single tap 'bit perfect' filtering, RC filter, etc etc, but my understanding is this would essentially require a perfect switch and a perfect clock and is not practical. Even with a multi-tap FIR filter doing the conversion, it IS the simplest, purest conversion you are ever going to get for DSD.)

And now you can have state of the art DSD upsampling with the best filters available to do so in hardware, so no need for complicated software to do the trick.

Also, unlike some solutions that only have Galvanic isolation on the I2S bus, but do nothing about pure USB power, nor galvanically isolate said power, the iFi is far superior in this regard, and will not benefit much, if at all, from external Galvanic Isolation, although the OCD in me doesn't want ANY dirty USB signals to cross into the DAC, period. Call it peace of mind


It almost like iFi took all these other popular and differing solutions to the same 'problem' and said we will one up you and offer them all. User gets to pick what they like best.

WOW. Just WOW.

Well done, and I can't wait to get my hands on one.

 

[iFi audio]

It almost like iFi took all these other popular and differing solutions to the same 'problem' and said we will one up you and offer them all. User gets to pick what they like best.

Thanks. 'Options' is our middle name.

 

[gordec]

Any early impressions anyone?

 

[bluesaint]

Just came tonight!

 

[bluesaint]

 

[Giraku]

Any early impressions anyone?

I got mine about a week ago. I've been overwhelmed by the sheer amount of the options. That's a good thing, but the problem is it will take some serious time to post an impression.
Another problem is that this is so good sounding so that I really enjoy listening through it and forget about critical listening...

 

[aterville]

The other resources (website etc.) only list for DSD filter a third order analog 80 khz cutoff with 6 db compensation for DSD level.

No mention of the usual four Burr Brown 8 tap FIR filter choices til I saw it here, so I was confused. So the implementation is like previous iFi products for DSD. Selectable FIR filter, with fixed filter following. (This fixed filter is in place for all formats, PCM included)

My only confusion now is the actual order of the filter (second or third), and how the 6db compensation is applied to DSD only and not the PCM formats?

Hello,

How do you mange DSD filter I can only access PCMs.

Thanks

Arnaud