**DISCONTINUED** Holo Audio – Spring 2 DAC – Level 1 / Level 2 / KTE

(4 customer reviews)

Spring 2 Dac has been discontinued and superseded by the new model Spring 3. We listened to our customers and implemented new features that were in demand. This is based on the same great R2R tech with some nice new features, with trickle-down features found in the Holo MAY DAC. Additional details to be disclosed on the launch date. Estimated for late-April to mid-May 2021.

Spring 3 Details:

Pricing (Subject to change):

Level 1 $1998
Level 2 $2298
KTE        $2798

All Models have optional Pre-Amp module for an additional $500. This is a fully balanced, discrete design.
The module can be installed at a later date if you change your mind.

Exclusive to the Spring 3 KTE model; The enhanced USB module found in the MAY DAC, which includes Titanis 2.0 FPGA circuit.

These will be first come first serve starting at a lead time (build time) of 4.5-6 weeks, shipping may add 4-5 days. Currently we are not accepting pre-orders.

This product is currently out of stock and unavailable.


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Slide show of the L2 Spring2 Dac. (Official Photos of KTE Spring2 Dac will be live second week of Dec approximately)

The Spring2 DAC has been Superseded by the Spring 3. Coming soon.


The KTE model will have the following specs. And many new features. Improved higher resolution display with ability to display more info at the same time such as input, OS or NOS modes and sample rates all at same time. While preserving the classic dot matrix font that the original Spring1 was known for!

Same chassis dimensions, same control panel and same copper/black signature look. but KTE model will have official pure copper KTE badges/emblems.

Improvements to the dac module have been made and KTE models will have hand picked modules for best performance and sound quality.

Also the USB module has completely new code written to optimize performance and reduce latency significantly. Low frequency performance (-40db) is also improved when compared to the already excellent sound quality of the Spring1.

The Spring2 dac (all three models) will also support DSD1024 native and PCM 1.536M output! Also, we have worked hard to reduce the common click noise with all dacs when switching from DSD to PCM. This sound click sound has been reduced significantly with a special circuit design. However it did not bother the majority of customers with the Spring1 design. We still addressed this issue to improve with our new product.

New improved power supply circuit with high performance regulation circuit using  2xCornell Dubilier and 4XPanasonic FC. (L1 uses Vishay ERO) and Mundorf Evo Gold/Silver oil Caps (L2 and KTE models). Also found in Spring2 are Nichicon Muse and Elna Silmic II caps.

We are no longer using LVDS and are now using a custom 4way circuit that isolates each line which further improves sound quality. such as the MCLK is isolated from data line and this improves jitter spec. (This feature i’m most excited for, as many of you know that I highly recommend i2s hdmi input as being ideal connection with our dac)

Now the dac is implemented with femto clocks, and also new discrete ultra high performance voltage regulators.

The Spring L2 and KTE version of the Spring2 dac also is now with a CNC machined aluminum remote control! (L1 does not have this feature)

All OCC copper wire replaced with 1.5mm pure silver wire, all plugs on the board are removed as we feel they were acting as a bottleneck. 1.5mm Silver wire is soldered direct to the pcbs with highest grade audio solder. Silver Rhodium Faston connectors used at IEC input

note: The silver transformer takes around 6 hours due to it being made/wound by hand, it is NOT machine wound.  And is pure 99.99% silver for its primary and secondaries.

The Kitsune Tuned Edition dac requires a significant amount of labor to produce and we are trying to keep the costs down as low as possible and within reach to most passionate audio lovers. Our markup on the components for KTE dac are very low. We build these Dacs due to our prime motivation being passion for audio. We are accepting orders now, and will produce them with estimate of about 4.5 weeks production time and will adjust as orders come in.

Prices are as follows for Spring2 lineup:




As of April 2020 shipping costs have gone up significantly due to COVID19. this is out of our control, we hope to see prices back down sometime 2021 but do not expect them to go back to normal for quite some time. 

Thank you for your support and understanding!

Holo Audio’s Spring 2 DAC – The KTE model is the fully loaded version with Silver transformer upgrade and Hand picked dac module, silver OType Transformer and Mundorf Cap upgrades etc.

Patented R2R technology. This is the first discrete DAC that has linear compensation and this allows for ultimate music reproduction accuracy. Dual R2R network for PCM, and Dual Discrete optimized resistor network for DSD! The World’s lowest distortion R-2R dac!


Newest Driver: HoloAudio Drivers – Win10/11 – v5.57.0_2023-02-22 (driver for both Gen2.0 and Gen2.1USB + DFU 5.57 tool and firmwares for Gen2.0)

Recent Drivers: HoloAudio Drivers – Win7/8/8.1/10 – v5.27.0_2021-10-20 (driver for both Gen2.0 and Gen2.1USB)

Firmware Gen 2.1 ONLY : NEWEST: Firmware for Gen2.1 USB ONLY (Post August20th 2021 dacs ONLY) “enhanced 3132” NOT for Gen2.0 USB  – best paired with the new v5.27.0 windows drivers.

Previous Drivers: HoloAudio Drivers – Win7/8/8.1/10 – v.5.00 +all firmwares MultiDFU tools 2021 for all products -CLICK HERE

note: May DAC and late 2020 Spring2’s do NOT need firmware update in most cases. They come shipped with 30.14 firmware, however if you need to use DSD1024 and PCM 1.536mhz than you would need to install 30.12 firmware which is less compatible with some devices but does support high res content with Intel Gen7,Gen8,Gen9, Gen10 type Intel boards and most AMD comparable motherboards. And some dedicated cards with Altera Chipsets.

these firmwares are also for other models – Cyan DSD or PCM, and Spring V1 or Spring V2. Please read instructions included carefully and entirely.

NOTES for new 5.00 Driver (this is a major release with firmware update for each model, Spring2 (two versions), Spring1, Cyan.

* New usb driver, 5.00

* Spring2 new usb firmware 30.12 (significant improvement of USB performance, and recommended for those using Motherboard USB (intel/amd) this is only firmware that supports DSD1024 and PCM1.536Mhz (all dacs ship with 30.14 for compatibility reasons) but you can use this if you have a modern PC with Intel/Altera USB chipsets. It works with most Gen7, Gen8, Gen9 and Gen10 Intel boards and comparable AMD boards.

* Spring2 new usb firmware 30.14(only support up to pcm768k and dsd512 but is DEFAULT firmware since late 2020). This firmware can be worked with those ‘hifi’ PCIE usb cards (JCAT PCIE Femto (renasas chipset), Linear Technologies PCIE Femto card, Matrix Element/ElementH USB card (texas Instruments). it’s most compatible with most usb cards and usb controllers. Also compatible with some special USB fiber optic cables.

* Spring Version 1 – new usb firmware 21.16. This fixes the problem roon has mentioned before, which has problem while switching between 24bit and 16bit at same sample rate.

* Cyan PCM or DSD – new usb firmware 21.06. This fixes the problem roon has mentioned before, which has problem while switching between 24bit and 16bit at same sample rate.


All new firmware must have installed the new 4.67 USB driver first. and then copy the directory of the firmware contents into the driver folder… commonly found in programfiles/holoaudio/USB Audio Device Driver/W10_x64/

then run the file “holousbaudioDfu.exe”

BE SURE you copied the appropriate firmware for your dac.

V1 and V2 spring are very different.

take note dacs from late 2020 were shipped with version 30.14 are for those with either JCAT Femto PCI-E card (renasas chipset) or the Matrix Element or Element H card (texas instruments chipset)
these are LIMITED TO DSD512 and PCM768 at this time.

HIGH content resolution firmware – version 30.12 is for motherboard USB chipset which is commonly Intel base USB controller and should support DSD1024 and PCM1.536Mhz as stated above in overview.

Spring V1 firmware is only one choice and has no issue with Jcat or Matrix USB cards, so no worries here. both Spring V1 and Cyan have known issue with Roon where changing from 24bit and 16bit sample rate can cause a problem. this is now fixed and addressed in the new firmware update.

ALL these new firmware updates improve USB transfer eye pattern in a significant way! there is a significant reduction in emi noise during USB transfer, and this means theoretically improving sound quality. Measurements confirm whether one can hear the difference or not.




Please read more about


(MUST READ article to explain why we recommend NOS)

*Please follow the Head-Fi forum thread here

*We are official Roon Partners here

*Please follow the Computer Audiophile thread here


Please read some reviews of our Spring1 dac below: (note the Spring2 is only improved over the Spring1 design and sound quality, its our well respected “house sound” that HoloAudio is known for.

#1 – Stereophile – Herb Reichart

#2 – ComputerAudiophile by Ted Brady

#3 – Headphone Guru by Peter Pialis

#4 – AudioStream by Michael Lavorgna

#5 – AudioStream by Alex Halberstadt

#6 – Basshead Club by Luckbad

#7 – SuperBestAudioFriends by Torq

#8 – Head-Fi by Torq

#9 – Stereophile Review by Art Dudley

#10 – GearPatrol.com Review by Ian

#11 – Jazziz.com Audio Gift Guide 

#10Youtube Review by Amos AKA Currawong 

General info:

Dimensions: 430 mm (W) * 300 mm (L) * 55 mm (H) additional 12 mm for machined feet

Weight: 8.5 kg


Does not include power cord, printed manuals.  (does not include remote control for L1 model, but the L2 and KTE model will include the remote control.)  Package includes DAC only + Remote for L2 and KTE models only! This speeds up the custom process. And most people won’t use generic power cords. 🙂


WARRANTY – 3 years warranty, both parts and labor, cover one way shipping (return shipping once product is confirmed a warranty claim). Be sure to buy directly from HoloAudio or authorized reseller and we recommend to buy from HoloAudioUSA<– this is KitsuneHiFi 😉 – Support is given from the source you choose to purchase from.

Click HERE for instructions on how to open the chassis properly with photos and step by step of which screws to remove and which ones to not remove 😀

Links below will be updated for Spring2 in near future. Most of these are still applicable to the Spring2. The manual is basically the same, but will have minor changes.

Download Windows System Icons HERE (image of Spring DAC, and kitsunetunededition logo)

FoobarDSD support HERE

Download Spring2 Hardware/Software Manuals HERE (includes Foobar2000/SACD will need FooBarDSD if you are planning to use FooBar2000) – FooBar is totally optional


If you have Windows older than 10, this is Recommended Driver: HoloAudio Drivers – Win7/8/8.1/10 – v5.27.0_2021-10-20 (driver for both Gen2.0 and Gen2.1USB)

Firmware Gen 2.1 ONLY : NEWEST 10/20/2021: Firmware for Gen2.1 USB ONLY (Post August20th 2021 dacs ONLY) “enhanced 3132” NOT for Gen2.0 USB  – best paired with the new v5.27.0 windows drivers.

OLDER DRIVERS: OFFICIAL Spring V2 Signed Windows Drivers +firmwares v4.67.0 Windows 7/8/8.1/10 – ASIO – HERE 

1/11/2019 (older) – Firmware update v.30.12 for USB Module – CLICK HERE to download

This update addresses a bug that was reported on 1/10/2019 from a customer who had issues with the volume control. This was a glitch with the algorithm of how volume is adjusted and was updated and fixed. Dac’s that shipped up until 1/11/2019 have v30.08 and we recommend updating the firmware to this new updated firmware. Some customers are not experiencing this issue. This firmware requires windows to update properly. You need to have the xmos v.4.55.0 drivers installed.  Please install these firmware files into your installation folder which should be located here.  C:\Program Files\HoloAudio\USB Audio Device Driver\W10_x64\

then run the DFU program. It should state you are upgrading from v.30.08 to v.30.10 or v30.12.  note: DO NOT have any usb devices between the dac and PC, some of these usb decrapifiers can cause issues with firmware updates and may cause instability so we recommend to be sure to use only a usb cable directly to the dac.


note: WIN7 users may have issue if you don’t have the most recent hotfix for SHA-256bit code signatures. By default Win7 only supports SHA-1 signatures, yet SHA-1 is obsolete and this hotfix is very important for security reasons. Win 8 and above have SHA-256bit by default. Some users reported these drivers not installing properly, so be sure your Win7 is up to date, or download the hotfix here (KB3033929) : https://support.microsoft.com/en-us/kb/3033929

This is special order item (will show “in stock” if able to order, this means we have the parts available for this dac and the order can be placed), with a typical 4.5+ weeks (estimated) delivery time to USA customers. Other voltage options than 110V (ie: 220/230/240V) may delay order an additional week. We will give you current estimate upon receipt of payment if it is different than the quoted 4.5+week estimate, and can be cancelled if you choose not to accept the terms to wait for the production/shipping times. After you accept the terms, I will place the order with HOLO Audio directly, as the order is considered a special order item there will be no cancellations or refunds if 48hours past date order was placed. The product is guaranteed not to be DOA and has multiple levels of quality control testing before it’s shipped out to you. We are confident you’ll be happy with your purchase.

NON USA customers please contact us for quote on shipping costs. Please include your full shipping address and phone number along with voltage requirements when requesting to order this dac. The same terms apply and estimated production times quoted above.


Shipping estimate varies, it’s best to email us for a current quote. (items in stock are only allocated for this batch, if you buy now, it will secure your position in our next batch)

if you are in Europe, please contact our European Authorized HoloAudio Dealer for the best service and support in your area, Magnahifi.com


 – Kitsune HiFi  


“NOTE: Be sure to say in notes what volt ac model you need, USA is 110 volt ac standard etc.  – Also note if you ask for special voltage transformer that it can delay your order up to a week longer.”

Kitsune HiFi carefully chooses products that we want to offer to our customers and be unique and/or stand out from all these audio supply stores. Jeff Zhu is a very talented engineer and is the brains behind HOLO Audio. Some say he is the man behind the curtain and he has certainly impressed us with his knowledge and his newest line of products that surely will leave you impressed too! The Spring2 DAC is his newest product and is capable of DSD native on an Discrete Resister Ladder DAC!  This spring 2 is capable of DSD1024 native and actually running on his bespoke discrete ladder DAC! This is a unique custom build discrete resistor network dac with linear compensation and advanced architecture based on R2R however we don’t refer to it as R2R since the design is far superior. This is our second discrete DAC that has linear compensation and this allows for ultimate music reproduction accuracy. Dual R2R network with advanced architecture for PCM, and Dual Resistor Ladder network with optimized architecture for DSD! We will be offering the first Spring 2 DAC’s in the USA and the KTE/Kitsune Tuned edition is no longer just exclusive to us. We have licensed the build as being the ONLY authorized modded edition of the Spring2 dac by HoloAudio. This means our authorized dealers will carry our KTE Spring2! And if you buy from a dealer you will get support from that particular dealer. Many may continue to choose KitsuneHiFi and will receive our excellent customer service that we are well known for.



You may be asking… well what is so special about this DAC? A Discrete R2R DAC with linear compensation…what is this?

There’s an additional R2R ladder in the Spring 2 DAC, it compensates the main R2R ladder. It works like trimming, but trimming is to change the resistor value. This additional R2R ladder is digitally controlled and will accurately compensate the resistor tolerance. For example, the MSB of 16 bits should have the value of 32768, but due to tolerance, it represents 32700 in real world results. Then that additional R2R ladder will compensate 68 into it. Thus it now becomes 32700 + 68 = 32768.  What this means is that it’s likely the most precise Discrete DAC on the market with near flawless linearity, lowest THD and highest SNR of any NOS DAC. The sound is simply something you must experience to fully realize how special this DAC is. It’s a patented technology exclusive to HoloAudio. KitsuneHiFi is also Holo Audio USA and proud to bring you this DAC.

Product Description:

This new DAC “Spring2” is the design of a new era, is a milestone for HoloAudio’s own Jeff Zhu. It’s a full discrete R2R type of audio decoder and does not have off the shelf-DAC chip! This is a bespoke custom-designed core DAC module and truly a breakthrough with technology for any DAC chip today. The Spring 2 is here to achieve new heights, new dynamics and simply a full spectrum of audio to please the aural senses.



Here at KitsuneHiFi, we have three versions of the Spring 2 DAC. Below are the three levels, and KTE being our no compromise model with all options:


(The base model is quite good all by itself and priced so competitively it’s impossible to beat the performance/price ratio.) This model has basic caps for the PSU, and does not include a CNC remote. It has standard Red label 5N Copper Otype Transformer, copper wiring. Considered the base model however packs a mean punch for price per dollar performance ratio. (no remote control in this version)


(With Mundorf Evo SilverGold Oil caps for ultimate power filtration and improved sound quality – Sound quality is refined and more relaxed, transparent and details are more refined and clear while remaining neutral. ) This is a popular option for those who want a little more out of their dac with improvement of sound from the caps as well as this version will include the cnc machined aluminum remote control.


The highest grade components are used in our very popular KTE version products. This Spring2 KTE version will include an upgraded ultra premium transformer that is 100VA O-Type green label pure 4N silver. Price is significantly more due to the OCC Silver Primary and OCC silver secondary wire used in this transformer. The sound improvement is not subtle, it’s a night and day improvement in our opinion and many of our customers agree. Kitsune has tuned this Spring 2 DAC for no compromise performance and targeted at the enthusiast audio lover. This transformer is our finest available model and makes the Spring’s sound quite elegant and improved detail. more features mentioned below.

This DAC was carefully implemented with some of the finest components.
The following is added to KTE Spring2:
1. 100VA O-type (NOT toroid) 99.99% Silver custom hand made audio transformer.
2. All copper wire is replaced with 1.5mm pure occ silver wire
3. Hand Selected Dac module to have best measurements compared to averages.
4. All PCB plugs and wire plugs are removed and then wire is soldered directly to the PCB
5. Replaced IEC inlet connectors with pure silver/rhodium plated faston connectors at the IEC inlet
6. HoloAudio Red Nano fuse
7. Mundorf EVO Silver/Gold Oil caps (we have done extensive testing and these prove to provide the very best sound quality)
8. Special Kitsune Tuned Edition branding inside and out (pure copper Kitsune fox emblem on top panel, like our extremely popular KTE SU1 DDR product)
9. KitsuneHiFi VIP service, english support and manuals/software
Green Label Silver Transformer
Pure 4N silver OType Transformer for the KTE model Spring2.


DSD is natively supported for the first time on this Discrete Resistor Ladder DAC

Holo Audio is the world’s first to support DSD natively on Resistor Ladder DAC, so far the only one. This is not the DSD converted to PCM before digital-analog converter, but directly by the discrete components of the DSD digital to analog converter. Supported currently on MAC (DOP)and Linux (DOP), and Windows/PC (Direct Native and DOP). Please note, the word ‘R2R’ is the name of a kind of architecture of resistor ladders. This architecture requires less resistors yet still is capable to deliver more than acceptable performance. Most DACs in the industry use this architecture. The DSD module of Spring 2 does not use R2R architecture for the DSD, more specifically it uses a very specific architecture which is optimized to perform DSD to analog. So to be entirely accurate the DSD part of Spring is using resistor ladders, not R2R..


Spring2’s input and output interface:

  • Digital input interface includes
  • USB (ground isolation)
  • RCA coaxial
  • BNC coaxial
  • AES
  • optical fiber
  • I2S (HDMI) – improved ultra high performance 4way custom circuit (NOT LVDS anymore)
  • All digital input interface supports DSD (DOP mode).
  • Analog Output interface: single-ended, balanced.

Spring2 DAC R2R structure and design + Input/output Stage

Modern and popular delta-sigma type DAC differs from R2R within one clock analog value can recover a sampling point, and the delta-sigma is used to represent an analog signal after passing through oversampling and high-speed digital switching 0 and 1. In comparison, the conversion structure of R2R is most direct and pure, but delta-sigma is essentially a digital chip, high-speed digital signals 0 and 1 switch to the low-pass filter to process the analog signal and this process is prone to various problems, produce digital sound (digititus) and also in the super-sampling process will inevitably cause some ringing and distortion. But DAC R2R structure requires high-precision resistor network which the cost can be very expensive. And the digital delta-sigma DAC chip in comparison is very low cost. Patented R2R technology. This is the first discrete DAC that has Linear compensation and this allows for ultimate music reproduction accuracy. Dual R2R ladder network with advanced architecture for PCM, and Dual Resistor Ladder network with optimized architecture for DSD!

I/O stages: There is an Op Amp used for input stage and discrete component used for the output stage. The discrete output stage is working in pure class A.  The output voltage is 2.0 Vrms for single ended output and 4 Vrms for balanced output. The single ended is RCA. Balanced is XLR. They both use the same output stage. It’s BiPolar Junction Transistors, direct coupled. The big MKP capacitor you can see in the output stage is for the power supply, not for signal coupling. And the output impedance is 200 Ohm. This has been reduced from previous design, as some customers request a “less hot” output for their very sensitive preamps. This should provide an absolute ideal situation for any preamp now.

A common question we get…” Why do you use an Op amp at the input of the DAC?”  

The input stage with an opamp is a good choice. It has a paired transistor input by the nature it is manufactured. But an opamp for the output stage is limited due to it’s size and the thermal capability. Also, no one will offer an opamp with class A output as it’s efficiency is so low. So an opamp used as input and discrete output combined together will have an advantage. It doesn’t mean that all discrete is not good. Actually, if we need to achieve enough low distortion. It needs at least 30-40 transistors. Which not only will it be huge and waste of space but it will also be too costly. I mean, to beat the opamp’s performance, a simple discrete architecture is not possible, although an all discrete design looks beautiful.


The true balanced circuit design

These two pictures can explain the true balanced design quite well. The bottom side has the same resistor ladders as top side. The dac module is a pure 24bit discrete R2R design (PCM) and discrete Ladder Dac optimized architecture (DSD).

(spring2 dac module is show only for reference)

XLR is using all of the circuit and RCA is just using half of them. The balanced output has better performance (THD, noise) and also better common mode rejection rate. If you’re listening environment contains interference, either from AC power or from EMI/RF then you will find a full balanced system can really help significantly.


With diverse and flexible sampling mode conversion mode

1: NOS mode: has no digital oversampling, the raw data is directly converted to analog.  Because digital oversampling will produce time-domain distortions, such as ringing, NOS avoids these problems. Generally NOS mode’s other performance indicators have a significant impact, but the Spring 2 is designed to allow top performance while in NOS mode.

2: OS mode: PCM is over sampled to PCM at a higher frequency, DSD is over sampled to DSD at a higher frequency, and then digital is converted to analog.

3: OS PCM mode: in either PCM or DSD the data will be oversampled to PCM and then digital is converted to analog.

4: OS DSD mode: in either PCM or DSD the data will be oversampled to DSD and then digital is converted to analog.


What are the Spring 2’s sound characteristics? :

One of the strong points of the spring is the spatial sounds stage presentation. It’s very wide and precise. It never sounds congested like many DACs. The high end is very detailed and never harsh sounding. It has the R2R goodness that many have come to know and love. R2R has almost a cult like following and this DAC will surely become a sought after DAC.  Everything comes effortlessly for this DAC. Bass is layered and textures, quite full and present without ever masking over the sweet mid tones that are produced. One special thing about the Spring is its amazing voltage regulation circuitry that better than 0.2uV output noise! This along with the O-core transformer helps regulate the purest power which translates to audio clarity and accurate reproduction. It must be heard to appreciate and come to love its sound. The Green Label transformer is a step up that brings a new level of clarity not even thought possible. The Red Label already sounds incredible, but if you must have the best and nothing compromised then we would suggest the KTE or Kitsune Tuned Edition.







Tim & Dawn Connor – HoloAudioUSA and KitsuneHiFi

We operate under strict business ethics and principle values. Our company motto we are always proud to mention to our customers, “Time will tell…” and this means that our products will earn the respect in a matter of time once people get their chance to test it themselves. Many companies need fancy buzz words and marketing to sell their products, we truly only need our customers to try our products and share their experience with others. Word of mouth is how our business thrives and we have many happy customers! We encourage others to try all the competition in the market and directly compare and see what type of value you are receiving. We are confident in our products and know that in time, our products will sell themselves once people get a chance to try them.  We offer tremendous value and quality without sacrificing on performance.


Jeff Zhu – HoloAudio  – founder/engineer

Jeff Zhu is the man behind this engineering achievement. Below are some comments that have been shared by Jeff to better explain this dac in his own words.  Holo Audio is founded by Jeff Zhu and the USA division was a partnership formed with Tim Connor and his wife, Dawn Connor.


A little note from Jeff:

Many have asked about how does a discrete resistor network accurately reproduce sound. This email is a good read for those who want a technical explanation on how Jeff was capable of achieving flawless linearity and ultra good specs on THD. This was a reply to a customer who had a technical question about resistors and their limitations.

“About the resistor tolerance, his word is partly right, but not accurate. The MSB of 16bits value only represent 32768, not 65536, all 16bits is 65535, but the MSB is only 32768. There are techniques to reduce this requirement. For example, segment+R2R, using segment into the first few bits, then r2r for the rest of them. Rockna is segment+R2R, TotalDAC is all R2R. And you can see, Rockna’s THD spec. is much better than Total. Total uses foil resistor, but they used the simplest architecture. That results an unsatisfied test performance. To my opinion, it’s some kind of wasting foil resistors. Soekris also uses segment+R2R. MSB’s old model is all R2R, but I don’t know about their new models.

Anyway, There are ways to improve the performance, the segment+R2R is one way. Trimming is another way. There is an additional R2R ladder in Spring, it compensate the main R2R ladder. It works like trimming, but trimming is to change the resistor value. This additional R2R ladder are digital controlled and is to compensate the resistor tolerance. For example, the MSB of 16 bits should have the value of 32768, but due to tolerance, it represent 32700 in real world. Then that additional R2R ladder will compensate 68 into it. Then it became 32700+68=32768.

Actually there are other ways to improve performance, I just told you two stories. There are more stories behind the design. It is really hard. I must count every via holes in layout, every PCB wire has it’s impedance and must put attention on it. A via hole can be 50 m Ohm, it is 1/20000 of 1 kilo-ohm, and you see, it covers 32768 which is the MSB of 16bits. Also the switches has self-impedance which is about several ohms to 30 ohms. If you find this issue. Maybe you will go crazy, it seems to be an impossible mission. But a good designer will overcome all these problems. It’s our value at HOLO Audio.

All the resistor tolerance, switch impedance, line impedance, via hole impedance, finally reflect as linearity. There is a chart that shows Spring’s linearity, it’s excellent. But I suggest you to look at THD performance. Bad linearity must result a bad THD performance. But good linearity doesn’t mean there will be good THD performance. THD is dynamic performance, more critical than linearity which is a static performance.

If you look at the THD performance, you will find Spring to maybe the best among those competitors. I’m applying a patent which contribute a lot of that performance. But I can’t tell you how. It’s confidential now.

Best Regards

Jeff Zhu”

And another note on Linear Compensation. As Some have asked what happens when the Resistors values change over time? Jeff responds:

No matter it is a digital switch or analog switch, they are built by transistors, can be either bjt, mosfet or jfet. They have self-impedance call Ron(impedance when at on state). If we expect a lower Ron, the a bigger transistor is needed. But bigger transistor has bigger self-capacitance that will cause switching speed to be lower. So there is no perfect components in the real world.

About long term drift, the modern resistor technology has made it much better than older process. But the most important thing is, we don’t care absolute drift, we only care relative drift. That means, if all resistors are drifted in the same direction and same speed. Then it will be no impact for this application. So, we make sure to use the same batch of components in a single board. That will minimize the problem causing by long term drift.

As I mentioned in the earlier email. Spring is not using trimming, but using compensation. Not matter it is trimming or compensation, their goal is same, to make the resistance much more accurate so the linearity and distortion can be improved a lot.

Best Regards
Jeff Zhu

Also, another customer asking about the oversampling, Jeff replied and has some good information to those who are curious.

The oversampling is done by AK4137, ‘OS PCM’ converts the input stream to PCM no matter it is PCM or DSD, then send to DAC. ‘OS DSD’ converts the input stream to DSD no matter is is PCM or DSD, then send to DAC. ‘OS’ over-samples the input stream. If it is DSD input, it over-sample to DSD256. If it is PCM input, it over-samples to PCM384K or 352.8K ‘NOS’ does no oversampling. send the input stream directly to DAC module.About DSD ‘native’, it is the way the USB transfer the stream. You know DOP, which is DSD Over PCM. DOP put the DSD into a PCM stream. At the receiver end, it just unpack the PCM stream and get the DSD back. DOP does NOT change any bit of DSD stream, just sending it with the package. So it waste some data rate. At the same data rate, DOP is 1/2 of DSD native, the other 1/2 is the package. So DOP and DSD native are all bit perfect. The DSD stream sending to DAC is all the same.So, now you should know, DSD native is just about the way it transfers the stream. Not describing the way it does digital to analog conversion. At the DAC stage, the DSD stream can convert to PCM then do the final digital to analog conversion. Actually, most DAC chips do this inside the chip. One point needs to be remembered, DSD streams can’t do volume attenuation. If this chip can do digital volume control under DSD mode, then is must converted to PCM already.Let’s go back to Spring. If Spring works in ‘NOS’ mode. There is no
oversampling, no conversion, just the original data doing the final digital
to analog conversion. I will not explain how it does PCM conversion, you
should already know quite well about it. There is a lot of resistor ladder
DAC, they are born to do this. I just explain how Spring can do ‘discrete
DSD conversion’. Actually it is like DCS and CHORD. If you looking to DCS
and CHORD’s PCB, you will find ‘discrete DSD conversion’ is also using
switches and precision resistors, like resistor ladder DACs. So, no matter
it is ‘discrete DSD conversion’ or ‘discrete PCM conversion’, they all use
the same discrete devices. Just work in different architecture. That makes
possible to combine these two modes in one device.

Best Regards
Jeff Zhu

Measurements –

Will post more info soon! very similar to Spring1 performance. This dac is best heard in person to truly appreciate it! Personally I prefer the new Spring2 design with many cool new features that make it a well rounded ultra high spec dac solution.



Our products are CE Certified for the European Market 

Additional information

Weight 20 lbs
Dimensions 16.93 × 11.81 × 2.63 in

Spring V2 KTE, Spring V2 L1, Spring V2 L2

4 reviews for **DISCONTINUED** Holo Audio – Spring 2 DAC – Level 1 / Level 2 / KTE

  1. Tim Stowell (verified owner)

    Absolutely phenomenal sound! I can hear every small detail in the music, very smooth and rich sounding. It’s amazing what details I had been missing out on using my prior DAC.

  2. Dean Fisher (verified owner)

    Wow…..the review recently posted on this in one of the audio mags was right on. About 30 hours in and sat down for some serious listening. Great space and articulation without being too analytical. Bass is natural and balanced. This thing is smoooooth….great midrange and the upper end extension is clear without being strident…..and it keeps getting better. I run through tubes (preamp or headphone)and the combination is great. USB port and coax hookups are very good. Very pleased with my Spring2 with Level 3 upgrades. Tim is a great communicator and product met my “very” high expectations

  3. Chris Moore (verified owner)

    Let me first begin by saying my entire experience with the holo spring 2 can be summed up in my first day. After warming it up I sat down to enjoy some of my favorite songs. From the first note to the last note of Bob Seeger’s “Like a Rock” I was streaming tears. For the next week every subsequent listen had a similar result. I have never heard such accuracy, dynamics, and overall realness to instruments and vocals outside of live performances. This dac single handedly was the best audio purchases I have made. Not to mention the longer I let it sit and stay warm the better it got. Throughout this process I was also able to connect with Tim Connor. All I have to say is what a lovely experience I had with him through all if my questions and emotional response. He truly is a master of his craft and an amazing person. I will continue to recommend the holo spring 2 to everyone interested in having the greatest musical experience of their life. This dac truly breathes life into any system it touches. I one day hope to try their May offering as well and can only expect great things from everything I have seen thus far.

  4. Filemon Tan (verified owner)

    I am writing this review after having this in my system for 2 months. It was with some trepidation that I sold my 3 year old Chord Qutest DAC to get the Spring 2 KTE without an audition. Tim was very helpful with my questions and I ultimately placed the order. I spent ~4 weeks playing music through my vinyl rig while waiting for the shipment.
    I have been always aware of difference in sound quality compared of the Qutest vs vinyl. With vinyl, the music had a greater sense of ease and I could relax into the music. There was a sense of 3D space/air around and in between the performers. The Qutest had lot of detail but it felt unnatural, as if I was looking a the musical performance with binoculars.
    I am happy to say that the Spring 2 KTE exceeded my expectations and I could not be happier. It has a very natural and analog-like sound. The sense of space rivals my vinyl rig, and its dynamics exceed it. Compared to the Qutest, I can more easily see (in my minds eye) the performance venue and how the musicians are arranged in 3D space. Perhaps this is why I find the Spring 2 less fatiguing and more enjoyable to listen to. The soundstage less forward compared to the Qutest but had greater sense of depth. To top it all off its beautifully made, with a subtle yet elegant in appearance.

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