Same DAC chip as ND555 and NDS

Just reading a review of a Swiss made DAC from CH Precision, and for the DAC duties, after oversampling they use “ Burr-Brown’s PCM1704 R-2R ladder DAC chip”, same as the current ND555 and its predecessor the NDS.

This DAC is not a copycat however, with some serious engineering and eye-watering pricing “ CH Precision C1.2 D/A Controller ($43,000 as equipped), aided at the moment by a complete CH Precision digital front-end: the X1 power supply ($20,500), the T1 clock ($24,500)”.

When the designer was asked why use this chip (4 of them, per channel) he replied “The fact that it is a monolithic chip makes it both consistent and wonderfully accurate to work with, something that a discrete ladder cannot achieve even with the highest precision resistors,” Cossy answered. He also wrote, “Even though it is an ‘old’ chip, it more than meets current requirements.”

So a new DAC design, operating in the upper atmosphere of HiEnd using the same DAC technology and designs as our Naim equipment despite all the ‘modern’ alternatives.

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When the forum visited a few years back they said they had cupboards full of these chipsets………cupboard probably getting bare by now.

The Burr Brown PCM1704K DAC chip is also used in the Naim DAC.

(And, iirc, a Soulution dac).

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According to Stereophile they cost $12.95 each for 1000 batch order back in 1998.

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Naim had a more stringent selection criteria so were probably even more expensive back in the day………they were difficult to make with a high failure rate, hence were discontinued.

pcm 1704 in not the only component nds and nd555 have in common, also:
40-bit SHARC processor with advanced signal processing
suspended brass sub-chassis

I love the sound of my 2014 NDS bought in 2022, exceptional value for money I think, I don’t feel the need of more modern machines to read music from my NAS

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My NDS is from 2016 (manufactured late 2015 according to the SN) and is just great, just used just as a UPnP streamer playing uncompressed WAV within a Roon system.

Here the Roon Core handles all manner of formats (MQA to 1st unfold, DXD, DSD 128-512, etc.) and services (Tidal incl. Tidal Master with the MQA support, Qobuz etc.) and gives my Roon Display on a screen I can see from across the room i.e. my TV, and the SonoreUPnP Bridge interfaces with Roon and sends the UPnP stream in WAV to the NDS.
The NDS/555DR combo has no more processing to undertake with no multiple format or internet services support required, just performing a function it was designed and optimized to do.

I have suggested that Naim strip out the Tidal, Spofity and iRadio functionality from the NDS firmware and just provide a ‘UPnP only’ stripped down mode and see how this sounds.

Plus the Roon setuo also plays into a bunch of Chromecast devices elsewhere in the house, plus the Mobile endpoint, Roon ARC for listening in original format while out and about and in the car.

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The chips themselves were graded at manufacturing by BB/TI with U, J and K designations. U being the chips measuring the worst values but still capable of being shipped and used in finished goods.
Despite the pedigree and status of the component, supply is the main issue. Longer term looking to the next 10-15 years of product design, Naim will have to consider what to do next. Ideally they would take the NRE hit and invest in doing their own design in-house with contract manufacturing of components.
They could always buy the IPR of the 1704 off of TI perhaps and make their own as an alternative.

Naim allegedly stockpiled enough of these DAC chips to ensure sufficient stock to produce the ND555 despite it being discontinued. That begs the question, how did CHP subsequently obtain stocks of the same chip. Perhaps stready demand has persuaded TI to continue production after all.

Do TI even still have the means to fabricate them, regardless of demand. You’d expect their manufacturing capacity was consumed by more lucrative lines.

Perhaps Naim will engineer their own ladder…when supplies dwindle…I suspect when the next big update comes for the ND555 … it will showcase a new platform…time will tell. I recon thats at least 2 to 3 years away.

I think the key thing is implementation - and that makes a huge difference. I am sure bit stream - could be Naim-ified…if they had to.

They have a job description for a field programmable gate array engineer on their website……new filtering like Chord etc?

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At the very least you’d expect some R&D cycles to evaluate the “art of the possible” given currently available technology, adapting technology currently available to a Naim design or even developing something fundamentally new and done in house.
There’s plenty of praise to be aimed at what is currently in mass production and available but eventually it no longer makes sense to maintain a platform or implimentation based on availability of components, platform support in firmware/software or more general changes in the market and consumer expectations.

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Aqua Hifi, TotalDAC, Monarchy … a number of very fine DAC:s have been build around the 1704.

I have some trace of memory saying they were built with a chip build-process not being used anymore. Perhaps having something to do with the new PSU not having the voltages needed for the nDAC etc … just guessing.

I thought the PCM1704 reached EOL long time ago and naim prepared for it purchasing a large qty?

Well cost per yield is quite significant. IIRC, Naim had two grades. CD555/ND555 and nDAC. Something like only 10% measure within Naim’s tolerance for the 555 series. And of what’s left, 50% measure acceptable for the nDAC. And the remaining chips are not used or possibly resold.

I might have the rejection ratios a bit off but I don’t think by much. So take that into account, including the time and expense of testing and grading them makes each chip quite expensive.

In fact a lot of Naim components go through a grading process with a high degree of perfectly in-spec rejects simply because the components are not within “Naim specs”.

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I wonder how they grade/measure each chip

And the remaining chips are not used or possibly resold. @ChrisSU wondered how CH Precision got hold of these DACs!!! (Just a joke in case the CHP lawyers are checking this thread).

Yeah, CHP obviously bought up the rejects. That’s why they had to use 8 of them in each box instead of just 2 in the ND555 to get it to sound any good. :crazy_face:

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