What is your experience with Digital To Digital Converters (DDC) and Audirvana?

Hi,

I listen a lot to headphones while I work. I kind of like the simplisity of just using the computer and not an extra streamer.

But I’ve read on many places that you absolutely should not connect a “normal” computer directly to a DAC. But is not Audirvana kind of optimised to work quite well direct out of a Mac Mini for example?

I got a a Mac mini M2 with Audirvana Orgin at the moment as a source. It is connected directly to a Denafrips DAC and a Violectric HPA V222 amplifier and Sennheiser HD-600 headphones.

Do you think I would hear a clear improvement if I would add a DDC from example Denafrips?

Hi @newmoon

Although I’ve never used a DDC, I’m struggling to see what benefit it would bring to your system.
In my opinion, the shortest path from source to output is invariably the best. So USB from your Mac mini to Denafrips.
I’m sure a few others on here (@Agoldnear , @Jud) may have a differing opinion :+1:

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100%

At work, Sennheiser 600 (great cans), keep it simple please :pray:

What output would you be using from a DDC into your DAC?

Which Denafrips DAC?

This is a loaded question, beholding to your ability to discern any qualitative change(s) if you were to usurp the clocking of your DAC with any DDC via I²S.

:notes: :eye: :headphones: :eye: :notes:

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I recently bought the new Ares 12th-1. I guess I should go for I2S that Denafrips seems recommend.

I2S is somewhat “flavor of the month,” and I’m personally not in favor. Here’s why:

A DDC/reclocker sounds like it ought to improve clocking and thus lower jitter, right? If you use I2S, that’s not the case. The reason is (as @Agoldnear hinted) that with I2S the master clock is in the reclocker, while with USB input the master clock is in the DAC itself. Why does this matter? Because when you are talking about femtosecond clocks, the larger distance from your reclocker to the DAC matters. With the high precision clocks now in use, you want them as close to the DAC chip as possible to minimize jitter. So that’s USB, where the DAC itself controls the clocking.

You’d be spending money on a more complicated system that would likely have worse jitter performance.

If you want to lower electrical noise into the DAC there are ways to do that while still using the USB interface and keeping jitter low. But these are more boxes and more money than the DDC. All in all, I think you’re well off with the simple system you have now, unless you really feel the sound you’re getting is so inadequate you want to spend the money (over $1000 US) and get into the complexity (3-4 more boxes plus some Linux).

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Thanks for your replies.

This video is kind of why I got interested in DDC:

Spot on. This is why I bought the Ares 12th-1 with I2S. But now I question if I made the right decision. :smiley: Denafrips kind of sell the Ares as a decent DAC that later on can be upgraded with a DDC for better sound.

Does it make a difference if the DDC has a better clock than what is in the DAC? This would be the case with the Iris DDC and the Ares DAC for example.

Please expand on what I would need if I would go that route (I got a main stereo system too).

You are mistaken… Your are reading something into the marketing rhetoric that is superfluous in the context of your DAC platform component topology…@Jud is giving you excellent insights in DAC platform topology that are indisputable regarding signal pathways and critical timing relationships… Do you see long digital-audio signal interconnect wires running around inside of the DAC? … The answer is NO…

Your DAC employs a very accurate clock that has been designed into the DAC platform topology in such a way as to optimize digital-audio code signal integrity, by reducing latency and eliminate noise potentials from multiple wire-based interconnection transitions among other gremlins (in today’s DAC platform topologies, signal clocking is typically done very well).… By using I²S you are exposing the digital-audio code signal to corruptions…

Typically the I²S connection in a DAC like this, is used for a SACD/CD player or a networked Streaming device…

Sit back… and enjoy the music… Stop fretting over something that is a non-issue in the case of this DAC, and is a waste of your time and money in consideration… Your money will be better served by investing in good power-conditioning and power-signal rectification, removing inducted EMF and RF noise and maintaining an ultra-clean ground/earth plane… To start put a good power-cable on this DAC.

:notes: :eye: :headphones: :eye: :notes:

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Thanks for your answer. @Agoldnear

Just to be clear, You mean I’m mistaken in that a DDC could be an upgrade? And that Denafrips possibly is kind of selling DDC as an upgrade (that would be a downngrade)?

Sorry English is not my native language.

Already ahead of you. :smiley: I’ve recently bought power board and cables and it made a noticable difference for my headphone setup:

Yes…There is no good technical reason for adding a DDC to your DAC, you will not perceive a tangible improvement over the fundamental output of this DAC… The other things I describe in application, will reveal more tangible improvements in sound-quality… What you are paying-for in the more expensive Denafrips DAC platforms, is more attention paid to the design of the power-topology and component selection among other design elements that may translate into tangible improvement in playback signal quality. (always a subjective assessment)

:notes: :eye: :headphones: :eye: :notes:

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I’ll get to your remaining question in another comment, but I wanted to address the video.

Why did people start using separate clocks? Because they saw the pros doing it. The reason the pros do it is because they have many different items of equipment in the studio to keep synchronized, so they use the separate clock as the “source of truth” for all of them.

This isn’t the situation for the home audio enthusiast. All you need a clock for is the DAC.

Why should the clock be as close as possible to the DAC chip? Because in a femtosecond, electric current moves about as far as the cross section of a particle that can get through a HEPA filter, about 300 nanometers. So from the point of view of your DAC chip, that outboard clock may as well be miles away.

What about the temperature variations the fellow in the video mentioned? Well, how much do temperatures in your listening space vary in a picosecond? Because it’s variations in timing across picoseconds or nanoseconds that concern us with jitter, not minutes.

So an outboard clock seems like money wasted IMHO.

Edit: One other thing - in the video, a great deal of attention is paid to the supposed jitter effects of dealing with a multiplexed signal. Multiplexing originated with telegraphy in the 1870s. The idea that a piece of electronic equipment a century and a half later would have to work hard to deal with such a signal is ludicrous.

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There are a few scenarios in a home audio playback system where an outboard clock will provide high quality synchronization of symbiotic components… This is when a system may have a SACD/CD player/transport, a digital pre-amp/DAC and/or just a DAC or some other outboard device like a Streamer that facilitate outboard clock-sync inputs… This common clock source then insures the digital-signal flow is not susceptible to component to component system clock variations that will precipitate noise related jitter…

:notes: :eye: :headphones: :eye: :notes:

High-Frequency PCB Traces

The clock signal paths in electronic circuits are designed as high-frequency PCB traces for reliability and signal integrity. The clock signals change from low-level to high-level quickly, indicating that the rise and fall time of these signals is very short. PCB traces should be capable of supporting these sudden changes and microwave and radiofrequency circuit signal paths should also be routed as high-frequency traces.

The Length of a High-Frequency PCB Trace

Time delays, reflections, electromagnetic interference, and crosstalk are some of the issues commonly seen in high-frequency PCB traces. These issues arise when the length of the high-frequency PCB trace is comparable with the wavelength of the signal. The length of the high-speed or high-frequency trace directly influences the performance of high-frequency circuits.

High-frequency PCB traces can be designed as either microstrip lines or striplines. The performance of these lines depends on the frequency of the signals passing through them and the length of the path. The length of the high-frequency trace should be designed so that the critical rise time of the circuit board is shorter than the rise time of the high-frequency signals.

The critical rise time of the circuit board depends on the critical length of the high-frequency PCB traces. As the length of the trace increases, the critical rise time of the PCB board increases and results in an impedance mismatch. In such cases, PCB traces of high-frequency need to follow impedance-controlled routing.
Link: Routing High-Frequency PCB Traces for Signal Integrity | System Analysis Blog | Cadence

:notes: :eye: :headphones: :eye: :notes:

Boxes:

fitlet3 – build-to-order – fit IoT (with the optical LAN option)

USB 2.0 Hi-Speed Isolator (whichever spec/color you like)

https://www.amazon.com/QNAP-QSW-2104-2S-A-US-Ethernet-Switch/dp/B0BFC6QFRL/ref=sr_1_3?crid=ETHJRAG9RZRC&keywords=qnap%2Bethernet%2Bswitch&qid=1699741826&sprefix=qnap%2Bethernet%2Bswitch%2Caps%2C132&sr=8-3&th=1

Depending on which Intona you get, with the Fitlet3 suitably equipped, and the optical fiber and transceivers you’ll need to connect the optical fiber at each end, these should come to just under or a bit over $1000 US.

Then you would install Ubuntu Linux Server (minimized install) on the Fitlet3, as well as SSH so you can connect with the operating system on the Fitlet, plus two more Linux apps, mpd and upmpdcli, which will when suitably configured give you UPnP streaming capability to the Fitlet.

You would connect the boxes as follows: Ethernet cable (copper or optical) from wall or WiFi router to the QNAP switch; optical fiber from switch to Fitlet3; Fitlet3 USB out to Intona; Intona USB out to DAC.

The switch, Fitlet3 and connections would all be 10 gigabit per second spec, not because you need the speed, but because the spec has an extremely low jitter requirement included in it. The Intona is to absolutely minimize any electrical noise from the Fitlet3 to the DAC. And so you would have an optically isolated low jitter low noise path connecting to your DAC’s USB input.

If you know enough Linux (or are sufficiently eager to learn) to want to do something like this, let me know and I can provide more detail.

Keep it simple… There is always a trade-off and nothing is perfect in a transmission-line containing multiple components with various power topologies and the slew-rates of transmitter and receiver circuit topologies that precipitate noise related jitter… It’s all about accumulated noise related jitter component that distorts the digital-audio code signal.

How Does Jitter Lead to Data Errors?
Information is extracted from serial data streams by sampling the data signal at specific instants. Ideally these sampling instants would always occur at the centre of a data bit time, equidistant between two adjacent edge transition points. The presence of jitter changes the edge positions with respect to the sampling point. An error will then occur when a data edge falls on the wrong side of a sampling instant.
https://www.analog.com/media/en/technical-documentation/tech-articles/an-introduction-to-jitter-in-communications-systems.pdf

:notes: :eye: :headphones: :eye: :notes:

@Jud
One question
In theory, should a DAC that has WiFi if connected without any cable, either USB or RJ45, have a cleaner sound?

@Reynaldo - You will see some people saying the WiFi will cause more noise, some saying the electrical connection will cause more (though copper Ethernet does have some galvanic isolation). I think it probably depends very much on implementation in the individual piece of equipment.

I think an even bigger consideration than noise is the problem that UPnP implementation is so variable among vendors. We’ve all seen the questions and complaints on the forum, and I can tell you from participation in another forum that this is certainly not limited to Audirvana. As you’ve seen me say before, this is a big reason (along with optical isolation) that I chose a DIY solution. What I had before was very well built from a reputable manufacturer, but it didn’t always work perfectly with Audirvana. With my DIY solution I can ensure the UPnP implementation remains strictly to specification, and I have had no problems so far.

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Wi-Fi has it’s own set of gremlins that can induce noise related jitter… there is no “Free Lunch” when you have electronic circuits involved (transmitter/receiver/power topology, etc, etc)… The salient question surrounds the BER (Bit Error Rate) of any given transmission system topology.