[Yanec]

Hey,

Thought it would be nice to have a complete list of portable R2R gear - both dongle DACs and DAPs one place.

I will keep expanding the list in this post as I discover new devices.

R2R dongles:
Cayin RU6
HiBy FC6

R2R DAPs:
A&K SE300
L&P P6, P6 Pro, LP6
HiBy RS series (2,6,8)
Cayin N6ii
HiFiMan R2R2000, HM 601/2/3, 801, 901, 1000
Altmann Tera-Player

Any rumours for upcoming portable R2R options?

Thanks for any additions or thoughts!

 

[msing539]

N6ii has an R01 module. And Cayin RU7

 

[Yanec]

N6ii has an R01 module. And Cayin RU7

Thanks added the R01 module above, but the RU7 isn't R2R.

Still the RU7 is an interesting concept too.

They get often confused due to the marketing wording, especially translated from Mandarin.

Let me provide some interesting comparison points for the curious.

The RU7 DAC does indeed use a resistor network, which might initially seem similar to the R2R ladder approach. However, there are important distinctions in how these networks function and are implemented.

1. Purpose and Design of a 1-Bit resistor DAC The RU7 network operates based on pulse-density modulation which involves very high-frequency switching of a single bit to represent audio waveforms. This single-bit approach is fundamentally different from the multi-bit, precise resistor matching found in traditional R2R ladders.
2. Architecture:
   • Resistor Network in 1-Bit DAC: This network technically forms a ladder, but its operation and design are optimized for DSD's 1-bit high-frequency data stream. This is less about the precise linear stepping through each binary level (as in R2R) and more about converting a very high-rate bitstream into an analog signal.
   • R2R DAC: Uses a multi-bit approach where each level of the digital code directly corresponds to a specific analog output through a resistor ladder. Each bit has a resistor that doubles in value as you move through the ladder, providing a direct and proportional analog representation of the digital input.
3. Conversion Method:
   • 1-Bit DAC for DSD: Uses high-speed switching and often relies on oversampling and noise shaping to achieve high fidelity, focusing on the purity of the DSD format which inherently uses 1-bit depth at a very high sampling rate.
   • R2R DAC: Converts digital signals into analog by summing currents through a network of precisely matched resistors, providing a direct analog equivalent of the digital input without the need for oversampling or complex filtering. R2R DACs are not inherently designed for 1-bit but rather for multi-bit PCM audio.

 

[gylyf]

Great idea! Depending on your definition of “portable,” xDuoo will soon be releasing an R2R module for the XD05 Pro.

 

[Yanec]

Great idea! Depending on your definition of “portable,” xDuoo will soon be releasing an R2R module for the XD05 Pro.

Yes, good catch, will add it once released, thought it's not very portable indeed. Thanks!

 

[Loftprojection]

Thanks added the R01 module above, but the RU7 isn't R2R.

Still the RU7 is an interesting concept too.

They get often confused due to the marketing wording, especially translated from Mandarin.

Let me provide some interesting comparison points for the curious.

The RU7 DAC does indeed use a resistor network, which might initially seem similar to the R2R ladder approach. However, there are important distinctions in how these networks function and are implemented.

1. Purpose and Design of a 1-Bit resistor DAC The RU7 network operates based on pulse-density modulation which involves very high-frequency switching of a single bit to represent audio waveforms. This single-bit approach is fundamentally different from the multi-bit, precise resistor matching found in traditional R2R ladders.
2. Architecture:
   • Resistor Network in 1-Bit DAC: This network technically forms a ladder, but its operation and design are optimized for DSD's 1-bit high-frequency data stream. This is less about the precise linear stepping through each binary level (as in R2R) and more about converting a very high-rate bitstream into an analog signal.
   • R2R DAC: Uses a multi-bit approach where each level of the digital code directly corresponds to a specific analog output through a resistor ladder. Each bit has a resistor that doubles in value as you move through the ladder, providing a direct and proportional analog representation of the digital input.
3. Conversion Method:
   • 1-Bit DAC for DSD: Uses high-speed switching and often relies on oversampling and noise shaping to achieve high fidelity, focusing on the purity of the DSD format which inherently uses 1-bit depth at a very high sampling rate.
   • R2R DAC: Converts digital signals into analog by summing currents through a network of precisely matched resistors, providing a direct analog equivalent of the digital input without the need for oversampling or complex filtering. R2R DACs are not inherently designed for 1-bit but rather for multi-bit PCM audio.

Thanks for this info, even though I don't really understand, haha, this is a great explanation of those two concepts. I believe there are two 1 bit DAC devices, the RU7 and the iBasso D16, both not very expensive devices like some R2R DACs. What's funny is even though according to your explanation, 1bit is not optimized for PCM music, both of those devices received praise for their sound quality that is supposedly similar to R2R, maybe it's because users of those devices use mainly DSD files?

 

[Yanec]

Thanks for this info, even though I don't really understand, haha, this is a great explanation of those two concepts. I believe there are two 1 bit DAC devices, the RU7 and the iBasso D16, both not very expensive devices like some R2R DACs. What's funny is even though according to your explanation, 1bit is not optimized for PCM music, both of those devices received praise for their sound quality that is supposedly similar to R2R, maybe it's because users of those devices use mainly DSD files?

The differences are beyond the theoretical principles how a dac works, they are in the actual implementation.

For r2r the level of tolerance and precision needed in matching each resistor pair is hardly ever met in reality.

This is what gives them their often poor measurements and their "sound". A transparent dac has no sound, r2r dacs often do as they aren't exactly transparent.

It is important to say that r2r are preferred by many exactly because of their "sound". It isn't necessarily that transparent is always the most pleasing. It's a thing of personal preferences.

I personally use and love both r-2r and d-s, for different moods, music genres or listening settings.

 

[Loftprojection]

Just found one in the PB5 thread I had never heard anything about. The Analog Squared Paper NOSDAC Type 1. An interesting option but there doesn't seem to be much info-reviews about it.

 

[Yanec]

Just found one in the PB5 thread I had never heard anything about. The Analog Squared Paper NOSDAC Type 1. An interesting option but there doesn't seem to be much info-reviews about it.

Yep a good catch, not very portable it seems but still not purely desktop. Thanks!

 

[Yanec]

My personal explanation why I and so many others like R2R sound, and what R2R DACs are (euphonic, very pleasant and fun sounding) and what they aren't (accurate, high resolution, transparent).

R2R DACs are not transparent, they are flawed and that's why very often they sound better than the transparent delta-sigma DACs, not because they are better or high quality.

R2R sound is definitely not natural by any means (as some claim). Actually the boring delta-sigma DACs are far more natural.
In terms of measurements R2R usually are terrible. Often they can't even cover the needed DR to play transparently even red book 16/44.1

And this is what makes them a very nice option! Don't get me wrong I like R2R, A LOT. Just want to provide real explanation of their sound not the bullsh*t that audiophiles and "reviewers" provide.

The R2R sound is characterized exactly by it's flaws that create a pleasant effect. Such flaws of R2R DACs (especially with lower tolerance like the FC6 or RU6 dongles) trigger psycho-acoustical effects:

• Wide/Deep Stage: Listeners interpret the distortions as added "details" or that this "layer" of extra sound represents extra "depth".
• Analogue/Vinyl/Non-fatiguing sound: Listeners interpret the rolled-off high frequencies as more analogue and easy sound.
• Stronger bass: Listeners interpret the rolled-off high frequencies as punchier bass - the two are always balancing out in our perception, lower highs give the illusion of punchier bass.

Thought this will help many to understand why R2R are perceived (very pleasant usually) the way they are.

I believe one should have both type of devices - fun/euphonic and accurate/transparent. For different purposes, moods or music genres.

Thought this will help many to understand why R2R are perceived (very pleasant usually) the way they are. I believe one should have both type of devices - fun/euphonic and accurate/transparent. For different purposes, moods or music genres.

As always there are exceptions (Holo DACs) and one can only look into the big picture in a single post.

 

[MidnightSun]

My personal explanation why I and so many others like R2R sound, and what R2R DACs are (euphonic, very pleasant and fun sounding) and what they aren't (accurate, high resolution, transparent).

R2R DACs are not transparent, they are flawed and that's why very often they sound better than the transparent delta-sigma DACs, not because they are better or high quality.

R2R sound is definitely not natural by any means (as some claim). Actually the boring delta-sigma DACs are far more natural.
In terms of measurements R2R usually are terrible. Often they can't even cover the needed DR to play transparently even red book 16/44.1

And this is what makes them a very nice option! Don't get me wrong I like R2R, A LOT. Just want to provide real explanation of their sound not the bullsh*t that audiophiles and "reviewers" provide.

The R2R sound is characterized exactly by it's flaws that create a pleasant effect. Such flaws of R2R DACs (especially with lower tolerance like the FC6 or RU6 dongles) trigger psycho-acoustical effects:

• Wide/Deep Stage: Listeners interpret the distortions as added "details" or that this "layer" of extra sound represents extra "depth".
• Analogue/Vinyl/Non-fatiguing sound: Listeners interpret the rolled-off high frequencies as more analogue and easy sound.
• Stranger bass: Listeners interpret the rolled-off high frequencies as punchier bass - the two are always balancing out in our perception, lower highs give the illusion of punchier bass.

Thought this will help many to understand why R2R are perceived (very pleasant usually) the way they are.

I believe one should have both type of devices - fun/euphonic and accurate/transparent. For different purposes, moods or music genres.

Thought this will help many to understand why R2R are perceived (very pleasant usually) the way they are. I believe one should have both type of devices - fun/euphonic and accurate/transparent. For different purposes, moods or music genres.

As always there are exceptions (Holo DACs) and one can only look into the big picture in a single post.

Thanks for this, I was meaning to look into it, so you just spared me some research effort!

 

[Yanec]

Thanks for this, I was meaning to look into it, so you just spared me some research effort!

R2R simulator for Foobar actually can replicate this fun sound signature (with any transparent DAC) with adjustable parameters, without selling the house and a kidney for Holo May Kitsune

 

[MidnightSun]

R2R simulator for Foobar actually can replicate this fun sound signature (with any transparent DAC) with adjustable parameters, without selling the house and a kidney for Holo May Kitsune

Hah, cool stuff, I'll play around with this this weekend, thanks!