What is Davina, and what happened to the pulse array ADC?

Davina is Rob Watts's project name for an analog-to-digital converter (ADC) built on his pulse array technology. In February 2016 he wrote of the ADC "(project code word Davina)" Head-Fi, Feb 2016. In April 2016 he wrote "Davina is the code word for the ADC project notionally intended for Dave. It will be the first product to use my Pulse Array ADC." Head-Fi, Apr 2016. A month earlier he said he could discuss Davina as a project but not Chord's future products, adding "Davina will also be a product" Head-Fi, Mar 2016. The sections below follow what he said year by year. Statements are about the Davina ADC unless noted, and several of the later ones are about the pulse array ADC without using the name.

He gives different start points for the work. In February 2016 he said "actually the first prototype was in 2001" Head-Fi, Feb 2016. In February 2015 he wrote "The pulse array ADC project has been running for 5 years so far" Head-Fi, Feb 2015. In a September 2022 talk he said he had been working on it "since about 2005" The Source AV 20:30. In September 2025, in a transcript, he called the pulse array ADC "a six or 7 year project" The Source AV 1:34. In the SoundNews interview (recorded in autumn 2026, published October 2026) he said Davina was started in 2016 article, Oct 2026, and a podcast transcript published in October 2026 has him working on the ADC "since twenty sixteen" Part-Time Audiophile 50:30. The items do not say how these dates relate; the 2022, 2025 and October 2026 podcast figures come, so check the recordings.

2014 to 2015: a pulse array ADC before the name

In April 2014 he wrote "I have been working on a pulse array ADC" with proper aliasing filters and several output sample rates, and added "This won't be available for some time though." Head-Fi, Apr 2014. In February 2015 he said the ADC anti-aliasing filters are "fairly" simple in requirement, and that he had eliminated the noise floor modulation problem found in current ADCs, though he had not started listening tests Head-Fi, Feb 2015Head-Fi, Feb 2015. In May 2015, in a transcribed interview, he said "next year we're doing the pro audio A to D converter" HIFICLUBE.NET JVH 4:50. In November 2015, on the DAVE thread, he wrote "ADC looks like starting in anger soon." Head-Fi, Nov 2015.

2016: Davina is named and specified

In February 2016 he wrote "I am currently designing a ADC converter, that will match Dave's performance", naming huge noise floor modulation, poor anti-aliasing filters and poor noise shaper performance as the problems in conventional ADCs Head-Fi, Feb 2016. A day later he listed noise floor modulation, aliasing and noise shaper resolution, and said test recordings would come "later this year", with samples published on Head-Fi Head-Fi, Feb 2016. The stated format was 44.1 kHz to 768 kHz with two different output sample rates available together, "without SRC", and a user-programmable bit depth of 16, 24 or 32 Head-Fi, Feb 2016. He said it would take analog inputs, so a user could play vinyl at 768k and record at 44.1 at the same time, and called it "a first step towards a pro audio interface" Head-Fi, Feb 2016.

In April 2016 he said his motivations were better sound and better understanding, and that Davina "mostly in the short term is about better understanding" Head-Fi, Apr 2016. The ADC would have 40 elements, which he said was the only way to reach his 350 dB noise shaper performance with DAVE-level distortion Head-Fi, Apr 2016. He targeted 135 dB SNR and said he hoped it would cost less than DAVE, but that "it is a technology prove of concept, its not about cost" Head-Fi, Apr 2016. In June 2016 he called it "really a technology proof of concept, as the pro audio market for a simple 2 ch. ADC is limited", with an 8-channel interface to follow if it worked Head-Fi, Jun 2016.

On schedule, in June 2016 he wrote "I have a history of always being late on projects", expected the PCB that month and prototypes by about September, and said tracks would not be published until the end of the year "at the earliest" Head-Fi, Jun 2016. In October 2016 he had given Davina a short break for another project and hoped to finish the PCB by the end of that month Head-Fi, Oct 2016. In late December 2016 he was "currently finishing off the first PCB layout" and called Davina "a performance driven project, not something that is determined by price", with a vague intent of DAVE's retail price Head-Fi, Dec 2016. In January 2017 he said no cost estimate existed Head-Fi, Jan 2017.

2017: PCB finished, prototypes ordered, and the loss test

In January 2017 he reported finishing the Davina PCB with only the front panel left Head-Fi, Jan 2017. He said Blu 2 came from the Davina work, and that M scaler mode "was always a feature of Davina" Head-Fi, Jan 2017. He described a mic input with relay-adjustable gain and switchable phantom power, and a bidirectional USB connection Head-Fi, Jan 2017Head-Fi, Jan 2017. In August 2018 he again wrote that Davina "comes equipped with it's own mic pre-amp, with adjustable gain and phantom PSU" Head-Fi, Aug 2018.

The purpose he stressed in 2017 was measuring losses. He wrote "Davina will tell me exactly how much loss in sound quality we get in going from 768>48>768 using an M scaler" and said he would publish the test recordings Head-Fi, Jan 2017. In October 2017 he told a CanJam RMAF audience it is "completely different to conventional A to D's" for three reasons: aliasing, noise shapers limited to 140 dB, and noise floor modulation miceblue425 36:03miceblue425 38:19.

On progress, in August 2017 he wrote "I am awaiting the hardware to turn up - the prototypes are being built now." and "it's not possible to give any kind of date" because he was attempting something no one had done, and a fundamental flaw could mean redoing the prototypes Head-Fi, Aug 2017. The same month he said Davina would match DAVE in size and be "comparable in price" Head-Fi, Aug 2017. In November 2017 he said he was too busy with other projects but should be back on Davina that month Head-Fi, Nov 2017.

2018 to 2019: filters, a failed simulation, and the back burner

In January 2018 he wrote "The prototype is waiting patiently for me to test it out" Head-Fi, Jan 2018. In July 2018 he said the 705/768 kHz to 44.1/48 kHz decimation filters were tested with "absolutely no aliasing (to 24 bit rounding error)", with the 104 MHz to 705/768 kHz filters next Head-Fi, Jul 2018. In August 2018 he said "Davina project has been on the back burner a bit", and wrote "I have set myself the target of actual recordings for next year" Head-Fi, Aug 2018. In an October 2018 post (date estimated from the post ID) he said studios "need Davina, and that's still a long way off" Head-Fi, Oct 2018.

In February 2019 he reported that the decimation filter from 104 MHz down to 768 kHz "failed big time on simulation" and had to be redesigned from scratch Head-Fi, Feb 2019. In a post dated by estimate to the same month he called Davina "my reserve project, so often finds itself on the back burner" and said "if I had concentrated on Davina, it would be ready today - but there would be no Hugo TT2 nor the Hugo M scaler" Head-Fi, Feb 2019. In June 2019 he wrote "Davina has been hit with hardware issues, and problems with the decimation filters - in particular the 104MHz to 768k decimation." Head-Fi, Jun 2019. In a July 2019 reply on the M Scaler thread he wrote "Mostly other projects getting in the way", adding discontinued devices and "issues with decimation from 104MHz"; the post does not name Davina and the question it answers is not preserved Head-Fi, Jul 2019. In November 2019 he wrote "You should see some more positive news about the pulse array ADC next year" and later "No news on Davina" Head-Fi, Nov 2019Head-Fi, Nov 2019.

2020 to 2021: a redesign around an unavailable part

In May 2020, after buying a ribbon microphone, he asked himself whether the ADC was close and answered "No I am afraid not." He wrote "I am working on another ADC prototype now (need to redesign as a device is now unavailable), so I expect to be recording later this year or early next year." Head-Fi, May 2020. In June 2020 he said the next prototype PCB was being worked on and "I have solved the issue of parts not being available." Head-Fi, Jun 2020. In July 2020 he said the first device would be a two-channel stereo test bench, "But ultimately the pro device will be multi-channel" Head-Fi, Jul 2020.

In January 2021 he said getting from 104 MHz down to 768k or 705k had become "a major headache", because studios sync to an external clock and he wanted the ADC on a clean local clock, and that "the work suggests that aliasing, if it's observable on a digital domain measurement, is easily audible - even when doing single blind listening tests" Head-Fi, Jan 2021. In February 2021 he wrote that he was "gently harassed by Emmy winning recording engineers at shows to get on with Davina" Head-Fi, Feb 2021. The same multi-reply post contains the line "I am not going to disclose my plans as I have over promised and under delivered on this before!", but the post does not show which question that line answers, so it cannot be tied to Davina with certainty Head-Fi, Feb 2021. In May 2021 he wrote that work on the ADC sample rate converter indicated "aliasing at -350dB is audible - so I now have to re-do those filters", which had been designed to -240 dB Head-Fi, May 2021.

In July 2021 he said the next ADC prototype PCB design was complete Head-Fi, Jul 2021, and in August that he would be "testing my pulse array ADC soon, and if that goes well - please note big if" a unit with analog inputs would follow Head-Fi, Aug 2021. In September 2021 he wrote "Davina got stalled with a key part no longer being available, and the pressure of other projects." and said he had a better method that removed the part, to be tested toward the end of the year Head-Fi, Sep 2021. On Christmas Eve 2021 he said the next prototypes for the pulse array ADC had arrived Head-Fi, Dec 2021.

2022 to 2024: failed spins, test recordings and a stereo prototype

At CanJam NYC (late February 2022, date unconfirmed; published March 2022), in a seminar transcript, he said he was respinning the ADC after a test that "didn't work", the fourth failed iteration, and the transcript reads as attributing it to power supply issues rather than the A-to-D design; the wording is garbled, so check the recording MFG Audio Reviews 51:01. In March 2022 he described helping his son record a practice session for a concert through a commercial Focusrite ADC, and said of the shortcomings he heard that "Depth will be vastly improved by using the pulse array noise shapers" Head-Fi, Mar 2022. In April 2022 he wrote "The xM scaler and the ADC are my current projects, I hope to be complete later this year." and that "the next ADC prototype will feature mic pre-amp inputs - but for ribbon mics as it doesn't have phantom power for capsules" Head-Fi, Apr 2022. Davina posts in 2017 and 2018 had described phantom power Head-Fi, Jan 2017Head-Fi, Aug 2018, and he does not say in the 2022 post whether this was a design change.

In July 2022 he wrote "my focus is on getting the pulse array ADC working, thinking about professional recordings with it is some way off!" Head-Fi, Jul 2022. In an interview published in August 2022 (recording date not stated) and a September 2022 stream he said his own Blumlein ribbon recordings were partly a test bench for the ADC AVstore 10:41The Source AV 20:30.

In January 2023 he hoped the next recording session in May would use his prototype pulse array ADC Head-Fi, Jan 2023, and said "the ADC coding is being finished, with hardware testing next week" Head-Fi, Jan 2023. In a February 2023 transcript he said he would test it "in a couple of weeks' time" Dusty Audio 46:13. In July 2023 he wrote "The pulse array ADC project hasn't been suspended - indeed I will be testing out the next version next month." Head-Fi, Jul 2023. In September 2023 he said "it's a stereo ADC that's being designed", with a sample-rate-conversion clocking option, that the pro version was not yet specified, and that Dante was one option under consideration Head-Fi, Sep 2023. In October 2023 he wrote "At the moment the ADC is just a simple 2 ch unit ideal for Blumlein recording with ribbon mics." and that "a solution to separate clocking without the usual loss in SQ has been sorted out" Head-Fi, Oct 2023. In June 2024 he expected to "have the ADC running by" autumn 2025 for recording with his son's musician contacts Head-Fi, Jun 2024.

2025: a pro audio product takes shape

In March 2025 he wrote that the earlier unit "worked perfectly up to -20dB" with the next board expected to fix "this final issue", that pro-audio specifications were being drawn up, and that "progress up to this point has been glacial, but it's now starting to accelerate, so I am now feeling pretty confident about this project"; he warned that a project at spec stage takes "18 months to two years minimum" to reach production Head-Fi, Mar 2025. Later that month he said his son Daniel was working with him full time for the next six months and had been given the pro ADC project, which "won't be a simple 2 channel ADC, but will include full EQ and processing, mic pre-amps, and DAC outputs" Head-Fi, Mar 2025. In September 2025, in a transcript, he said the pulse array ADC had been tested in the last couple of days, called it "a six or 7 year project", and described a high-end unit with two DACs and a parametric EQ, targeting 192 kHz and 768 kHz recording The Source AV 1:34The Source AV 2:20. In a podcast recorded in October 2025 (published March 2026) he said he was developing a Pro Audio ADC with recordings "fairly shortly", and that his ADC noise shapers "just about manages to do 301 dB" ecoustics 18:59ecoustics 45:04.

2026: the ADC inside Quartet, and the pro ADC next

In a video published March 2026 (recording date not stated), of "the best A to D on the planet using the same technology that's within Dave", he said "And we now have that working with Quartet." Audio Force 29:58. In a second Audio Force Thailand video published May 2026 (recording date not stated) he said "With Quartet, I've developed a Pulse Array A to D converter", the first product to use it, and that the Pro Audio ADC was under development Audio Force 16:00. In August 2026 he said Quartet was finished, that it contains a pulse array A-to-D converter, and that the intent was to put the technology into a pro audio interface with mixing, EQ and compression The Source AV 2:17. Of a 768 kHz studio session that month he said "we've proven the concept" and that the job now was to turn it into a product pro audio users could use The Source AV 3:46.

The fullest account of what happened to Davina is in the SoundNews interview, recorded in autumn 2026 and published in October 2026. He said "by the time I got to test Davina, some of its components had been discontinued and there was no replacement. So I thought, right, there’s no point in me testing this thing, because we can’t produce it. So the design was scrapped." He then faced replacing a crucial part, a flash converter, and "parked it" article, Oct 2026. Chord asked for an analog input on Quartet, and he said they considered either a separate ADC or one integrated with the scaler article, Oct 2026. Integration made the added cost small, and "it went from a project that I’d like to do to a project that had to be done" article, Oct 2026article, Oct 2026. A podcast transcript published in October 2026 has him saying that with Quartet "we decided that with Quartet we would put a pulse array ADC into it" Distorsiuni Interioare 15:29.

On results, he said two test recordings had been made with Quartet and that he had expected better instrument separation, depth and power, but that the surprise was the pitch reproduction of female vocalists, which he attributed to aliasing in other ADCs Distorsiuni Interioare 11:57Distorsiuni Interioare 12:51. In print he said the female vocalist "sounded out of tune on the commercial ADC and in tune on Quartet" article, Oct 2026. He also said that with 768 kHz recordings he could now decimate to 48 kHz, return to 768 kHz and compare, and that if there is a large change "we need to keep working" article, Oct 2026.

On what comes next, he said in a podcast published October 2026 (recording date not stated) "the next big project is the Pro Audio A D C" and described a 16-in, 16-out interface with FPGA mixing, subjectively lossless EQ, and possibly compression and reverb Part-Time Audiophile 49:46Part-Time Audiophile 53:34. In the SoundNews interview, of the Quartet test recordings, he said "this is just a test of the ADC itself" and "The pro ADC will be DAVE standard, and what we’ve currently got is sort of Mojo standard." article, Oct 2026. He said his son is doing most of the work on the pro ADC, and the sound from the test recordings has him excited about the technology Distorsiuni Interioare 1:18:54.

What he has not said: no release date or firm price for Davina or the pro ADC (for Davina he gave only a vague intent of DAVE's retail price and "comparable in price" Head-Fi, Dec 2016Head-Fi, Aug 2017), and no product name for the pro ADC. He has not said whether the Quartet ADC reuses Davina's design or is a new one; he says only that Davina's design was scrapped when parts were discontinued and that the pulse array ADC went into Quartet article, Oct 2026Distorsiuni Interioare 15:29. I found no item saying whether the Davina test recordings he promised to publish in 2016 and 2017 Head-Fi, Feb 2016Head-Fi, Jan 2017 were ever released, and no item stating that a Davina unit was completed and sold.

Quotes

“Davina is the code word for the ADC project notionally intended for Dave. It will be the first product to use my Pulse Array ADC.”2016-04-24 Head-Fi, Apr 2016

“So I thought, right, there’s no point in me testing this thing, because we can’t produce it. So the design was scrapped.”2026-10-17 article, Oct 2026

“Davina got stalled with a key part no longer being available, and the pressure of other projects.”2021-09-14 Head-Fi, Sep 2021

“But now I’ve proven the technology. I’ve proven what it can do from a sound quality point of view.”2026-10-17 article, Oct 2026

Dated positions

Caveats and open points

• Everything here is Watts's own account. This archive contains no independent measurement, specification sheet or product announcement for Davina or the pro ADC.
• He gives different start points for the work: first prototype in 2001, about 5 years running by February 2015, since about 2005 (2022), a six or 7 year project (2025), and Davina started in 2016 (2026). The items do not reconcile them.
• The transcript of the passage about the failed 2022 prototype is garbled.
• Two posts are dated by estimate from the post ID (Head-Fi, Oct 2018 and Head-Fi, Feb 2019). Head-Fi, Jul 2019 does not name Davina.
• The unavailable part is described as a device in 2020, a key part in 2021 and a flash converter in 2026; the items do not say whether these are the same part.
• Head-Fi, Feb 2021 contains the line about having "over promised and under delivered", but the post does not show which question it answers; it is not attributed to Davina here.
• The SoundNews interview was recorded in autumn 2026, after CanJam SoCal in late August, and published in October 2026, and the ecoustics podcast was recorded in October 2025 and published in March 2026 (sources.json); both are dated here by recording, and the podcast items from October 2026 by publication.

Topics: Davina and ADC design, Future products and project status