FiiO K13 R2R DAC - Music for Eyes, Ears & much more.....

[Dipym]

Let me try explaining what did I find.
Taal is one of my regular listening album and I am totally familiar with all of its songs. Swapping between R13 R2R to D50 (blindly) didn't give me any clue which one is which. They were in the cabinet with level matched volume set and powered ON all the time regardless which one was playing.
Did K13 R2R loose any details, NO. I even make some specific notes to specifically focus but I had both doing same thing.
Pneuma wasn't different either with one after another blind switching.
This is really not different than what I got when I initially added K13 R2R in my setup.

But the main difference comes in when you leave one of them playing for long time, like a day or two and then got it switched (blindly).
For example, I left D50 playing on Saturday all day. I am in Atlanta and snow storm got us all trapped over the weekend inside the house.
We had a jam over the weekend, with some friends while doing doing these comparisons.
On Sunday afternoon, I got it switched (unknowingly) to K13 R2R and, believe me or not, all day we kept on saying that now everything is smooth and kind of laidback that I prefer. This time we weren't comparing (because we weren't switching back and forth) but everything we played Sunday evening/late evening was relaxing. I totally knew something changed but wasn't able to put finger as to what changed other than saying this is good and later I verified that K13 was connected while it was D50 before.

It might not matter but I had Revel M16 speakers playing over the weekend and room mode around 60-70 Hz was lowered in using Wiim Ultra's PEW but was was same with both the DACs.


My friend, I gave these couple of attempts but it wasn't of my liking. Transilvanian Hunger was kind of unbearable, nothing was clear enough for me to observe anything really.
It might be the case that speakers I have (Revel M16, Emotiva XT, Ascend Acoustics Sierra-LX and JBL HDi1600) aren't suitable for such music, I tried these on all these except Emotiva.


Tracy chapman - fast car, Wondering where the lions are - Bruce, many of Larissa Liveir's songs, etc. are my go to music after a extremely busy day. Nothing beats this playlist, lights down and a glass of merlot (or two) for me, other than my favorite Sachin's knocks.
You mentioned Fast Car and I am listening it with K13 R2R while writing this post. Her vocal reverbs and dynamics in this song are breathtaking.

I don't know really how did people come to conclusion that K13 R2R looses details or something. May be they mean details don't pop out the way they expect or something.

To sum up, I would say its more about preference. D50 surely has darker background because things pop out more noticeably which gets my attention more. I used to like that a lot but sometimes I just don't want that, other than if someone is over my place and I want then to say my rig sounds very clean and loads of details to brag about.

I am getting Fosi's new BT20A Max in a week or two because it has 2 RCA inputs with remote which will help me get some fun trying 2 DACs. Return policies here does favor as you easily get 30 days or more to try something at home and send back if you don't want it.
By the way, I have also got Fiio R2R Warmer DAC which is R2R with tube buffer.

Don't know if this is going to help in making a decision but I tried what I could.

Haha I get it. If there is an already a good transparent system in place i don't think the overall aural experience changes in extreme metal. I mean i gave you some of the worst recordings. But maybe you should try some cleanly produced albums like judas priest - sad wings of destiny or painkiller, motorhead - overkill, iron maiden - seventh son of a seventh son, and candlemass - epicus, doomicus, metallicus

 

[mosesarm]

Nice review. Looking forward to a long term review of this dac. I’ve been considering this dac but didn’t really have a reference point with reviews.
Actual user feedback is always preferable.

 

[0verkilled]

Thanks a lot for this @guddu478 @morerajendra5678 super helpful. Im leaning towards the R2R based on your observations, and also the fact that Hypex would end up amplifying everything cleanly, ESS dacs might sound harsher. I will check with headphonezone if they have some way to test these.

 

[morerajendra5678]

Im leaning towards the R2R based on your observations, and also the fact that Hypex would end up amplifying everything cleanly, ESS dacs might sound harsher.

ESS Dacs when used with tube Pre-amplifier never sounds harsh. It is just more balanced. R2R Dac when used without any Pre-amplifier doesn't have the slam in bass but carries lot of midrange weight but again lacks a bit in high frequency. Using Tube Pre-amplifier adds a bit in bass slam and corrects a lot in high frequency dispersion. The midrange becomes dominant with lots of weight and also has the thick tone trait.
Incase someone is just looking for slam in bass with good high frequency dispersion out of R2R Dacs they can add a solid state Pre-amplifier which doesn't render the thick tone trait to the R2R Dacs.

Low priced and mid priced R2R Dacs benefit out of the use of Pre-amplifier with it. But even high end ESS Dacs benefit out of tube Pre-amplifier.

 

[Mayasandra_l]

ESS Dacs when used with tube Pre-amplifier never sounds harsh. It is just more balanced. R2R Dac when used without any Pre-amplifier doesn't have the slam in bass but carries lot of midrange weight but again lacks a bit in high frequency. Using Tube Pre-amplifier adds a bit in bass slam and corrects a lot in high frequency dispersion. The midrange becomes dominant with lots of weight and also has the thick tone trait.
Incase someone is just looking for slam in bass with good high frequency dispersion out of R2R Dacs they can add a solid state Pre-amplifier which doesn't render the thick tone trait to the R2R Dacs.
Low priced and mid priced R2R Dacs benefit out of the use of Pre-amplifier with it. But even high end ESS Dacs benefit out of tube Pre-amplifier.

I would be interested in knowing what ESS DACs did you hear to come the conclusion that ESS DACs paired with SS Pre sound harsh. From my hearing experience, this is a completely incorrect assumption. A well made ESS DAC does not sound harsh. Do listen to a well made ESS DAC like T+A, Sim Audio Moon or a weiss dac and you would definitely change your stand. I also heard to the recently released ESS DAC from Gustard (X30) - absolutely beautiful. This bashing of ESS DACs has come from the Topping DACs that release DACs catered to the measurement crowd but do sound flat (and dare I say - harsh). My request to all is hear all topologies of DACs- Delta Sigma, FPGA, R2R and then choose what floats your boat. Pre-assumed thoughts in todays market no more hold true.

Also from my experience, an analogue and matching Pre Amp is essential, irrespective of the price point or topology of the DAC.

 

[morerajendra5678]

I would be interested in knowing what ESS DACs did you hear to come the conclusion that ESS DACs paired with SS Pre sound harsh. From my hearing experience, this is a completely incorrect assumption. A well made ESS DAC does not sound harsh. Do listen to a well made ESS DAC like T+A, Sim Audio Moon or a weiss dac and you would definitely change your stand.

My statement is different. My statement is "ESS Dacs when paired with tube Pre-amplifier never sound harsh". This statement of mine includes all ESS whether well made or not and is also irrespective of price point of ESS Dac. I have heard almost all the Dacs that you have mentioned. Since it was about ESS Dacs in general and not a few high end ones only, I put forth this statement of mine so as to benefit others who might have a not so well implemented ESS Dac. Tube Pre-amplifier can be used to add warmth and smoothness to the system.

This bashing of ESS DACs has come from the Topping DACs that release DACs catered to the measurement crowd but do sound flat (and dare I say - harsh).

My statement of using Tube Pre-amplifier was directed towards those who have ended up having up having a badly implemented ESS Dacs for some reason or the other.

My request to all is hear all topologies of DACs- Delta Sigma, FPGA, R2R and then choose what floats your boat. Pre-assumed thoughts in todays market no more hold true.

Is it a bigger challenge today to audition Hifi gear before making a purchase. Only few blessed ones do get to audition stuff before making the purchase.

Also from my experience, an analogue and matching Pre Amp is essential, irrespective of the price point or topology of the DAC.

Cannot comment much on this as I have good exposure to Streaming only and not other kinds of sources like CD Playe, Audio Cassettes or Vinyl. Through my post I have tried to outline possible combination of Pre-amplifier and Dacs based on what I felt about it as I got extensive opportunity to play around with variety of Dacs and Pre-amplifiers.

 

[Dipym]

Let me try explaining what did I find.
Taal is one of my regular listening album and I am totally familiar with all of its songs. Swapping between R13 R2R to D50 (blindly) didn't give me any clue which one is which. They were in the cabinet with level matched volume set and powered ON all the time regardless which one was playing.
Did K13 R2R loose any details, NO. I even make some specific notes to specifically focus but I had both doing same thing.
Pneuma wasn't different either with one after another blind switching.
This is really not different than what I got when I initially added K13 R2R in my setup.

But the main difference comes in when you leave one of them playing for long time, like a day or two and then got it switched (blindly).
For example, I left D50 playing on Saturday all day. I am in Atlanta and snow storm got us all trapped over the weekend inside the house.
We had a jam over the weekend, with some friends while doing doing these comparisons.
On Sunday afternoon, I got it switched (unknowingly) to K13 R2R and, believe me or not, all day we kept on saying that now everything is smooth and kind of laidback that I prefer. This time we weren't comparing (because we weren't switching back and forth) but everything we played Sunday evening/late evening was relaxing. I totally knew something changed but wasn't able to put finger as to what changed other than saying this is good and later I verified that K13 was connected while it was D50 before.

It might not matter but I had Revel M16 speakers playing over the weekend and room mode around 60-70 Hz was lowered in using Wiim Ultra's PEW but was was same with both the DACs.


My friend, I gave these couple of attempts but it wasn't of my liking. Transilvanian Hunger was kind of unbearable, nothing was clear enough for me to observe anything really.
It might be the case that speakers I have (Revel M16, Emotiva XT, Ascend Acoustics Sierra-LX and JBL HDi1600) aren't suitable for such music, I tried these on all these except Emotiva.


Tracy chapman - fast car, Wondering where the lions are - Bruce, many of Larissa Liveir's songs, etc. are my go to music after a extremely busy day. Nothing beats this playlist, lights down and a glass of merlot (or two) for me, other than my favorite Sachin's knocks.
You mentioned Fast Car and I am listening it with K13 R2R while writing this post. Her vocal reverbs and dynamics in this song are breathtaking.

I don't know really how did people come to conclusion that K13 R2R looses details or something. May be they mean details don't pop out the way they expect or something.

To sum up, I would say its more about preference. D50 surely has darker background because things pop out more noticeably which gets my attention more. I used to like that a lot but sometimes I just don't want that, other than if someone is over my place and I want then to say my rig sounds very clean and loads of details to brag about.

I am getting Fosi's new BT20A Max in a week or two because it has 2 RCA inputs with remote which will help me get some fun trying 2 DACs. Return policies here does favor as you easily get 30 days or more to try something at home and send back if you don't want it.
By the way, I have also got Fiio R2R Warmer DAC which is R2R with tube buffer.

Don't know if this is going to help in making a decision but I tried what I could.

Hi. Did you buy the BT20A Max and fiio warmer yet?

 

[bunny_hop]

Great detailed review and thoughts!

Recently purchased the FIIO K11 R2R to experience how different it is to delta-sigma. Have paired it with Yamaha A-S701 & now Technics SU-VX600. Listening to my music collection.

 

[guddu478]

Hi. Did you buy the BT20A Max and fiio warmer yet?

Yes I did
Fiio Warmer is a different story….. very likable.
BT20A Max is very handy with 2 RCA inputs and remote switching, performs very well.
I have some captures taken with Mofi Sourcepoint 8 speakers comparing frequency response in-room among 3e A7, Aiyina A20 and Fosi BT20a Max. I will put all that in a thread soon.

 

[guddu478]

Fosi BT20A Max

G

Thread 'Fosi BT20A Max - Practically more useful approach to a power amplifier'

Mar 6, 2026

BT20A Max - Fosi's first TPA3255 PFFB Stereo Amplifier​

Quick highlights:

- TPA3255 PFFB based stereo amplifier with active FAN inside case over amplifier chip assembly and remote control

Front Panel

- Motorized Volume, Bass, Treble controls knobs

- Multifunction Button: Power ON/Off & input selector

Back Panel

- Input: 2 x RCA inputs, Bluetooth (QCC3095)

- Output: Speaker Out, Sub-Woofer out

- HPF Toggle: 80 Hz fixed High Pass filter, Two Settings: 80Hz or OFF

- 12v Triggered input, tone bypass button & DC Power input (32-48v)

Packaging & Contents

-...

• guddu478
• Replies: 0
• Forum: Amplifiers

• 

Fiio Warmer

G

Thread 'FiiO R2R WARMER – A Vintage Bliss'

Mar 6, 2026

A rather unique “Tube buffered R2R Balanced DAC with VU meters” for little over 300$.

“If you are reading this post then I can safely say that you have some interest in R2R & Tube tech without being overly analytical about their objective measurements and parameters.”

R2R Tube DACs are not rare, what’s rare here is that this one does not cost over two grand $ like others, to say the least.

Most Audiophiles just swear by R2R and tube stuff. As they say, the tube character (by adding harmonic distortion) added by tube buffer might sound pleasing especially with certain...

• guddu478
• Replies: 0
• Forum: Digital + Analog Converters (DAC/ADC/DDC)

• 

 

[sand87ch]

I would be interested in knowing what ESS DACs did you hear to come the conclusion that ESS DACs paired with SS Pre sound harsh. From my hearing experience, this is a completely incorrect assumption. A well made ESS DAC does not sound harsh. Do listen to a well made ESS DAC like T+A, Sim Audio Moon or a weiss dac and you would definitely change your stand. I also heard to the recently released ESS DAC from Gustard (X30) - absolutely beautiful. This bashing of ESS DACs has come from the Topping DACs that release DACs catered to the measurement crowd but do sound flat (and dare I say - harsh). My request to all is hear all topologies of DACs- Delta Sigma, FPGA, R2R and then choose what floats your boat. Pre-assumed thoughts in todays market no more hold true.

Also from my experience, an analogue and matching Pre Amp is essential, irrespective of the price point or topology of the DAC.

i have a moon 340d3x playing via b&w603 s3 and i cna say that the ess is a bit glaring at its high freq.its a bit lean in the mids and hence i had to adjust the eq at my wiil pro plus end

 

[sand87ch]

FiiO K13 R2R - DAC & Headphone Amplifier with Pre-Amp, Digital Volume Control & PEQ​

View attachment 94111
View attachment 94112
View attachment 94113


R2R DACs aren't new but never be as affordable.

While Objectivists won't stop "not liking" them because their measurements aren't top tier for their likings..... Subjectivists often find them more likable than others.

FiiO have been bringing such DACs into the market lately and here I am giving FiiO K13 R2R a serious try keeping objectivist inside me switched off.

As a hobbyist, my interest normally incline towards Audio Source, EQ, Amplifiers and speakers. It's simply because my experience with DACs (Delta Sigma specifically) so far have ended being same (or inaudible) really after living with so many. Their may have different features for different needs but overall sound quality found to be just transparent.

First I want to take basic details out of the way, so summarizing basic feature set:

- 24 bit R2R DAC and headphone amplifier

- It has fully differential design which, in theory, should have noise & distortion eliminated

- Inputs: Optical, Coaxial, Dual USB type C and Bluetooth 5.4

- Outputs: 2 set of RCA (single ended) and XLR (balanced)

- Decoding Modes: Over Sampling (OS) and Non Over Sampling (NOS) modes

- 10 Band Parametric EQ (PEQ) - accessible thorugh mobile app or web GUI on laptop through USB connection

- Built-in power supply (AC input), as well as external DC input option

- Remote Control (plasticky but responsive)

Please find more product details and specifications here:

https://www.fiio.com/k13r2r

*****

FiiO K3 R2R - Build Quality & Aesthetics

*****

K13 R2R is simply stunning in looks. FiiO have a way to adding a touch to the appearance K13 R2R.

Build is excellent, feels solid as oppose to similarly priced DACs which kind of looks plasticky.

Front display is large enough to read from 3-4 meter distance for me, with useful information in large display font. Top cover has round glass showing R2R module with different LED colors.

Combining all this, K13 R2R is a joy to look at every time....... quite different than looking at black box looking DACs.

*****

Time to clear up facts on operation modes - OS vs NOS

*****

Over Sampling (OS) Mode - Standard mode used by a DAC to construct a technically more accurate analog signal applying upsampling, digital filtering, shaping, etc.

Non Over Sampling (NOS) Mode - No additional processing applied after Digital to Analog conversation

*Note that OS/NOS modes are not specific to R2R DACs, Delta-Sigma DACs have same modes as well.

*Note that FiiO K13 R2R DAC has OS mode set by default, should be changed manually by Left Front Knob if desired.

While Objectively, OS mode is required to get more accurate noise/distortion/shaped/frequency-artifact-free signal achieving higher noise & distortion numbers, subjectivists prefer NOS mode often arguing that its pure unaltered output.

*****

Here is the setup I have in action

*****
View attachment 94114
TV --> optical_out --> Wiim Ultra --> optical_out --> Fiio K13 R2R --> RCA_out --> RCA_Switch --> 3e A7 Amplifier

TV --> optical_out --> Wiim Ultra --> RCA_out --> RCA_Switch --> 3e A7 Amplifier

Please note that the further details I am going to mention here are based on experience and opinion using K13 R2R in the mentioned setup.

*****

FiiO K13 R2R DAC - in action

*****

??? - Which mode should you use with K13 R2R

Technically speaking, Am I wrong to say NOS mode should sound kind of incorrect or something not-right?

Let me say the opposite, I did not find K13 R2R NOS mode incorrect, non-accurate or anything like that.

If anything, I found it really COHERENT and so easy to listen to.

??? - What about OS vs NOS on K13 R2R

I personally could not really detect any real differences if someone else was changing the mode re-playing the same song that we heard several times on this setup, and so many times in general.

Sure there may be differences, the best I could say probably minor.

*****

R13 R2R DAC - Sound Quality

*****

To begin with, I must say I really like it in my rig.

The best I can describe it is "absolutely COHERENT, engaging and easy to listen to".

I have several other DACs or streamers with DACs and it's not that I don't like them or something.

However, I am inclining to K13 R2R for what it brings on for me in my setup. This DAC doesn't push my attention to anything in specific within a song and gives me focus on the overall music or song. Its like somehow everything is neutral and balanced, nothing more or nothing less.

If I focus on specific part of a song or music for details, those are SURELY there. I did not find NOS mode loosing any details in a song or OS mode pushing anything additional as per say.

Both modes gave me very smooth and non-fatigue output.

??? Did I try blind test with SPL level matched - Sure I did

I am living with this setup from more than couple of weeks, and I do have RCA out from Wiim Ultra to same amplifier (3e A7, which I know is a transparent amplifier) as well.

I have done switching to Wiim output to RCA (blindly, by someone) and I could easily tell this one isn't R13 R2R because it changes the character as I mentioned above.

Likewise, OS & NOS blind switching was done several times.

??? But what about SINAD

Looking at the specs provided by FIIO, the SINAD score comes out around 78-79 dB SINAD.

My own experience says it is good enough for any use.

?? Does it produce any hiss, pop or other noise on power ON/OFF or on idle when nothing is playing

Absolutely nothing, I found it dead silent

Now that the basics are out of the way, time to explore PEQ feature.

*****

FiiO K13 R2R - Bluetooth Performance

*****

While I am a heavy audio streaming consumer, I also often use BT for background or casual music playback while I work or read.

K13 R2R has Bluetooth v5.4 and support SBC/AAC/LDAC

iPhone uses AAC and I had no issues at all using it with iPhone.


I also paired K13 R2R with nVidia Shield Pro and it automatically used LDAC which excellent reliability supporting high fidelity.



*****

Exploring PEQ - Swiss Knife Edge

*****

K13 R2R has 10 band Parametric EQ (PEQ) function.

It is packed with 10 pre-set EQ profiles and 10 user defined sets for your custom configuration.

Customized EQ could be saved on the device or FiiO Cloud using Personal tab with a free account.

It also allows you to import custom EQ file from connected device.

*It took me some time to get to a point to use PEQ and so I am capturing the process here hoping that it might save you some time if you follow the process:

??? How do you access PEQ feature - FiiO Control Mobile App vs Web App on Laptop/PC

1> FiiO Control Mobile App

Available on Google Play Store & Apple App Store

App discovers the device if its powered ON

Allows to change certain settings like Knob indicator & top indicator LED lights


*Note - Requires to enable EQ (any profile) on K13 R2R first to use PEW features on App

You can use sliders to customize the EQ



***To use Detailed PEQ settings, go to "More Options-> advanced"



2> Web App on a PC or Laptop

*Note - Requires USB connection between FiiO K3 R2R and PC/Laptop

*Note - K13 R2R has 2 USB C ports - Any of them could be used for this

*Note - Any EQ profile must be enabled on K13 R2R to access PEQ settings on Web App

When connected over USB, WEB App access uses "https://fiiocontrol.fiio.com/"


>> On the Web App page, you need to first connect your K13 R2R device to the Web App

>> Use "Connect" button on upper right of the page and select the correct device


* Note - If EQ is not enabled on K13 R2R device then you will se following error. Make sure to enable any EQ mode using knob or remote first.


>> You should see "FIIO K13 R2R" shown in place of connect button on upper right corner after successful connection, like this:


>> Use "Device" tab on left panel to access all EQ profiles:


>> You can select a profile here and then go back to "Home" tab again to make the changes to EQ bands.

>> You can save the EQ profile and save the changes to device directly or make your custom EQ and save to Personal tab (FIIO Cloud account).


*Note - You can create a free account to use these advanced EQ save & upload from device features. You may also explore community shared EQ profiles & settings.


***Note - I have not explored different headphone auto-EQ options in details yet, but those are available under "Auto-EQ" tab on left panel.

What did I miss in K13 R2R

While I normally look at a product for what it is rather than what it isn't, however the following would have really enhanced user experience:

*12v Trigger and/or signal sensing auto-ON/OFF (*Note - K13 R2R has a SHUTDOWN timer)

* Separate PEQ for each channel, currently its stereo PEQ applied to both the channels


Summarizing all the thoughts........

FiiO K13 R2R is my DAC in-use now from last more than couple of weeks and feels like it will remain there my daily DAC now.

It has quite a coherent and balanced smooth presentation that I liked. It is more so apparent after listening it for a day or two and then switch to another DAC.

It isn't a SINAD chaser, but it doesn't fall behind at all in my experience and opinion.

Overall, it is really nice looking device, well built, feature packed and sounds soooo good.

If you are eyeing on a R2R DAC then this one is absolutely worth a look.... Don't miss it if you need one.

Hope this has been informative for you and help in making a decision.

have you heard the denafrips ares 15th.if yes how does the K13 compare with the ares 15th?

 

[guddu478]

have you heard the denafrips ares 15th.if yes how does the K13 compare with the ares 15th?

I am afraid I haven’t.