New 28-bit DAC coming out.

[Matt_Holland]

This device is apparently designed for production work (where more 'resolution' is commonly needed).

I understand the need for 24bit or higher in the DAW to allow for mixing level headroom, but for analogue conversion, we solved the problem decades ago and current state of the art (available for $hundreds) far exceeds the resolution of human hearing.

 

[antcollinet]

and to my ears the D-1 is easily in another league, though that does not mean everyone will like it.

Now that the Imersiv D1 is on the market and available for end users to test in their studios and homes, the real “science” is in why they might be hearing differences compared to previous state of the art equipment and designs.

That is easy - in the absence of well controlled blind comparisons:

They've been told this DAC is the bees’ knees with 10s of dB's lower noise floor - so they "hear" it as better.
They've spent a lot of money on acquiring this "obviously" better DAC - so they hear it as better.
They are listening carefully - already knowing that the amazing tech is going to deliver unrivalled sound quality - so that is what they hear.

The 'real science' is already well understood. But it lies in the realm of psychoacoustics - not in the realm of electronic design and engineering.


This device does have a benefit in the world of recording studios - where it enables recording with much less need to worry about matching gain/levels. But for playback it offers no objective benefit - at least as far as what we know about human auditory capabilities is concerned.

If someone is able to prove via competent blind testing that it *can* make an audible difference for playback - then they will not only be turning what we here at ASR understand on its head, but will also be advancing the fields of psychoacoustics, and of the biology of the human ear.

 

[krabapple]

Now that the Imersiv D1 is on the market and available for end users to test in their studios and homes, the real “science” is in why they might be hearing differences compared to previous state of the art equipment and designs.

You have it backwards.

We already have the science that likely explains 'why' they claim to hear what they do.

What they need to provide is evidence that that likely explanation is wrong.

 

[knownothing]

That is easy - in the absence of well controlled blind comparisons:

They've been told this DAC is the bees’ knees with 10s of dB's lower noise floor - so they "hear" it as better.
They've spent a lot of money on acquiring this "obviously" better DAC - so they hear it as better.
They are listening carefully - already knowing that the amazing tech is going to deliver unrivalled sound quality - so that is what they hear.

The 'real science' is already well understood. But it lies in the realm of psychoacoustics - not in the realm of electronic design and engineering.


This device does have a benefit in the world of recording studios - where it enables recording with much less need to worry about matching gain/levels. But for playback it offers no objective benefit - at least as far as what we know about human auditory capabilities is concerned.

If someone is able to prove via competent blind testing that it *can* make an audible difference for playback - then they will not only be turning what we here at ASR understand on its head, but will also be advancing the fields of psychoacoustics, and of the biology of the human ear.

Exactly.

kn

 

[Bleib]

We'd benefit a lot more if ADCs were improved

 

[knownothing]

My admittedly very weak understanding is that bit depth controls the loudness or maximum difference in loudness in a recording, and sampling frequency affects the time signatures or resolution at which sound is sampled in time. The discussion of the Imersiv D1 revolves around the decibels that can be reproduced and the difference between noise and signal at low decibel levels in a recording.

I am wondering if this device design does anything unusual in the time domain? Dramatic upsampling of low resolution recordings like a Watts FPGA?

kn

 

[krabapple]

It controls the headroom *and* the minimum difference in sound level that can be captured (resolved) -- aka the resolution. I've seen it compared to 'grain' in the video realm.


Sample rate does not determine the resolution in that sense. It determines the highest frequency that can be captured.

 

[Bland_username42069]

4 bits of extra veil lifting - and a potential breaking of the sound of blackness barrier

 

[KSTR]

Similar concept is used in Cirrus Logic chips

Very obviously it is NOT a similar concept. Please read up.

 

[EJ3]

4 bits of extra veil lifting - and a potential breaking of the sound of blackness barrier

If we break the "sound of blackness barrier" our heads may explode! Where is Chicken Little? We need him to get on this right away!

 

[IVX]

Very obviously it is NOT a similar concept. Please read up.

The principle is the same(a switchable gain), but the implementation is different. Cirrus uses a single DAC + gain control; D1 uses two DACs with a different gain. What should really be the same are the audible artefacts and fake Dynamic Range.

 

[antcollinet]

4 bits of extra veil lifting - and a potential breaking of the sound of blackness barrier

Even at 24 bits there is no blackness barrier (Assuming I understand what you mean by that). The noise floor of 24 bit is at least 40dB below what the most sensitive human ear can detect. It is also around 50dB lower than the noise floor of your typical amp, and 24dB below the noise floor of the best amps ever tested here.

 

[Jcrow]

Even at 24 bits there is no blackness barrier (Assuming I understand what you mean by that). The noise floor of 24 bit is at least 40dB below what the most sensitive human ear can detect. It is also around 50dB lower than the noise floor of your typical amp, and 24dB below the noise floor of the best amps ever tested here.

I think he’s talking about a noise floor akin to a black hole. Opens up a new dimension of transparency.

 

[signalpath]

What should really be the same are the audible artefacts and fake Dynamic Range.

The D1 exhibits zero perceptual artifacts. The original Cirrus architecture is vastly different than D-1 HDR-A architecture.

D-1 dynamic range specification (168dB) is real. In multi-path architecture, there are two noise floors, the low-path floor and the high-path floor. Noise only matters when it's audible. D-1 high-path noise is (worst case) 90dB below program, what we call "DSNR" or Dynamic Signal to Noise Level. Study the Fielder papers (at Dolby) from the 1980s where he measured the audibility of noise under program.

D-1 dynamic range specification is paralleled in the Linearity specification, which is also 168dB. This is un-measurable on an AP555X, which will start exhibiting its own non-linearity around 140dB.

It bears repeating that the D-1 was designed for the professional user, who can benefit from enhanced operating specs. We've spent 35 years in the pro world, with over 50,000 channels of audio shipped into the highest levels of acoustic recording. We've never marketed into the audiophile world, never advertised there. But now the audiophile world has found the D-1, and we find ourselves selling into that market. We just had our very first audiophile review last week. https://twitteringmachines.com/review-imersiv-d-1-dac/

Anyway, our specs are not "fake". The pro world would banish us. But I can see why you would say that, due to the high-path noise floor. But noise is only a problem when its (1) measurable, or (2) perceptual. In the D-1, neither is true. The only appropriately-considered noise in the D-1 is the low-path noise, which is -146dBu, as calculated.

I will add that virtually every issue raised in this comment thread has been addressed in the imersiv FAQ. Read the FAQ and respond to the FAQ, not hearsay or assumptions. If you find something "fake" in the FAQ, let me know (send me PM, that way I'll get notified). If we've made an error, we'll address it. https://imersiv.com/faq/

 

[thcdru2k]

Take a look at the system used in that review... Gauder, Gryphon, Grimm, Perlisten. I’ll give the benefit of the doubt that in a system like that, the experience described is real.

The only scenario where something like the Imersiv DAC could be audibly advantageous is in an ultra-quiet, highly resolving, DSP-free 2.0 system with excellent speakers and ideal recordings, where the system noise floor is low enough to expose extremely subtle low-level differences.

Even then, those differences would be very small and difficult to isolate without controlled, level-matched comparisons.

Outside of that, speakers, room, and processing dominate the audible result.

 

[markstein]

@signalpath: Again, will you perform a "blind, large-sample ABX trial" as announced earlier in this thread and ideally involve ASR?

I assume this would immediately stop the ongoing discussion.

Edit: If the performance of your new DAC is as good as advertised, this should be a no brainer!

 

[popej]

D-1 dynamic range specification (168dB) is real.

It is claimed performance. No real validation. Please publish THD vs output level and noise vs output level.

 

[Purité Audio]

Take a look at the system used in that review... Gauder, Gryphon, Grimm, Perlisten. I’ll give the benefit of the doubt that in a system like that, the experience described is real.

The only scenario where something like the Imersiv DAC could be audibly advantageous is in an ultra-quiet, highly resolving, DSP-free 2.0 system with excellent speakers and ideal recordings, where the system noise floor is low enough to expose extremely subtle low-level differences.

Even then, those differences would be very small and difficult to isolate without controlled, level-matched comparisons.

Outside of that, speakers, room, and processing dominate the audible result.

That is exactly what manufacturers of ‘high-end’ equipment would have you believe, but in real life components are entirely characterised by their measurements and more expensive rarely means better, just more expensive.
Keith

 

[popej]

D-1 dynamic range specification is paralleled in the Linearity specification, which is also 168dB. This is un-measurable on an AP555X, which will start exhibiting its own non-linearity around 140dB.

This would mean:
- quality control not possible,
- no real life gear, that would profit from better specification.

 

[rolfrander]

an ultra resolving DAC completely unnecessary

I think this is the key here. A DAC with resolution above what your speaker+room-combo is able to reproduce and what your ears are able to hear is "completely unneccessary"