Dac Technology Mature?

In my opinion, manufactures are doing everything they can to "get a leading edge" in technology - instead of focussing on music. Overall the dac chips gives very little to the complete sound. I would say the digital part in total would contribute no more than about 15% or so to the complete sound. The psu and analog stage, combined with pcb layout matters more.

I used to own arguably the best Delta Sigma dac ever made, the Vimak DS-1800 Mk2. Vimak invented Delta Sigma dac technology, and the DS-1800 to my knowledge is the only dac of its type implemented with a discrete architecture. Such an incredibly complex design would be too expensive today. Now all Delta Sigma dacs use miniaturized chips. Yet even the Vimak would be soundly beaten out by most high end dacs today. But that’s not because of digital audio converter. Component and material quality, psu’s, upsamplers, tolerances etc have also improved over time, as has manufacturing equipment. And there are many more manufacturers in the market today.

I currently own a Vitus SCD-025 Mk2 cdp which uses two Analog Devices AD1955 dacs in mono mode. I recall asking Hans Vitus if they’d compared the AD1955 to other highly regarded NOS dac chips like the BB PCM-1704k or TDA-1541A double crown. I was told they had compared them to everything & that in the context of their design requirements, there are others that are good, but not directly better - just "different".

So in summary, yes I think dac technology is now mature and should remain so for some time, however new standards will continue to appear over time like DSD and MQA. My spinner supports up to DSD128 and 32bit 384KHz PCM, but not MQA (though I personally think MQA is a gimmick). Hence if you were considering buying a high end dac you plan to keep, it makes sense to look for a dac which is modular in design (like Vitus) that enables upgrades over time. My 2c.

@frozentundra @jond Thanks for your kind words. PS Audio make some nice gear, though their designs as you pointed out have limited upgradeability. I see firmware updates for the dac as a kind of pandora’s box; you could just as easily subjectively move forward as backwards in sound.

A fully modular dac offers greater flexibility and would be more future proof which helps protect your investment. Vitus for example are offering a dac/streamer module for the new Vitus RI-101 integrated amp which supports Airplay, Roon, MQA, Tidal, Spotify, etc. And i’m told they are planning to offer a streamer module for my player in future.

Picking up on Shadorne’s comment, remember it’s all about implementation. And that comes down to the skill of the designer and the company’s manufacturing capacity. As I said, the digital part (incl: the dac chips) in total would contribute no more than about 15% or so to the complete sound. The psu and analog stage, combined with pcb layout matters more.

bigkidz                                                                                                                     08-04-2018 11:51am
1,646 posts
Picking up on Shadorne’s comment, remember it’s all about implementation. And that comes down to the skill of the designer and the company’s manufacturing capacity. As I said, the digital part (incl: the dac chips) in total would contribute no more than about 15% or so to the complete sound. The psu and analog stage, combined with pcb layout matters more.

Quote citation missing, but it’s all good ;).

I think some members are confusing terms, as in adolescence > maturity > dotting off to the nursing home. I reckon it’s fair to say that after 50+ years of constant development, DAC technology has reached “maturity”.

Dac technology has been largely worked out for 20+ years. For example, Vimak corporation who invented Delta Sigma technology implemented the only truly discrete Delta Sigma dac; the DS1800Mk1 released 25 years ago which was incredibly complex and over-built. Now, Delta Sigma dacs are implemented in miniaturized chips. And in the process I think they lost something actually.

But that doesn’t mean DAC technology is standing still, or that manufacturers aren’t innovating. Data Conversion Systems proprietary ring dac and APL Hifi’s proprietary DSD dac are good examples.

@ejr1953 I agree with you that dacs have greatly improved over the years, but not because of radical improvements in dac chips. More so for the reasons I eluded to earlier. Component and material quality, psu’s, upsamplers, clock accuracy, boards, tolerances etc have all improved over time, as has manufacturing equipment (incl: computers).

frozentundra OP 08-04-2018 11:07pm
105 posts

Gents;. And Ladies!

You are all wrong....

Then why ask for input if you could answer your own question & were not well disposed to alternate points of view? We could have all been spending our time on something more useful like reading a book or doing housework..

georgehifi 08-08-2018 6:35pm
4,118 posts

BTW: I remember that maybe Technics invented the first Delta Sigma, and they called it MASH.

Cheers George

I was told that Vimak invented Delta Sigma theory by one of the few high end audio engineers who has serviced the incredibly complex DS-1800Mk2 dac. As I understand it, Vimak Corporation hold the design patents for the technology, or atleast did (as patents expire). The other factor supporting that contention is that Vimak are the only manufacturer to have ever implemented a fully discrete Delta Sigma dac, as opposed to the usual chip-based design. However i’m happy to be proven wrong if anyone has information to the contrary.

@georgehifi Interesting. Here is a list of Patents assigned to Vimak Corporation - https://patents.justia.com/assignee/vimak-corporation
That list includes the following patent -

Multiple clock signal generator apparatus Patent number: 5266908 Abstract: A digital-to-analog converter--preamplifier apparatus serving as an interface between a source of digital audio signal data and an amplifier is disclosed. A digital stage receives multiple digital audio signal inputs, a selected one of which is analyzed by a digital audio interface receiver, processed by a digital signal processing device and a delta-sigma modulator prior to passing to the analog stage for conversion from the digital domain into left and right channel analog audio output signals. Volume control is performed on the audio signal in both the digital domain and the analog domain in order to optimize performance and minimize noise. The present invention automatically adjust for input word lengths of greater than 18-bits.

Type: Grant

Filed: January 26, 1993

Date of Patent: November 30, 1993

Assignee: Vimak Corporation

Inventors: Michael A. Koulopoulos, Russell A. Siggelkoe, Thomas R. Hegg

What I am certain of is that Vimak held relevant patents for the only truly discrete implementation of a Delta Sigma dac i’m aware of. And whilst they may not have invented Delta Sigma theory, they developed it to it’s ultimate potential using proprietory technology in the DS-1800Mk2.

Archimedes has firmed up at 2 to 1 odds, but I heard someone was offering 200 to 1 odds that Plato invented Delta Sigma theory. How do I get some of that action?!