This is a preorder of our NEW dac, The Kitsune Tuned Edition Spring 2 with many improvements over the Spring1 design. We are extremely confident our customers will be absolutely thrilled with our new version to replace the original spring dac. We will update this page with new content in the near future. However many customers have request we get a page up to begin preorders. As we are actually building them now and ready to ship them soon! Professional Pictures will come soon! Please forgive us for the poor image of the product, this is really just a teaser. Photos are scheduled to be done early December.
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 offical 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 dac 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).
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
(AudioMagic) Ultimate Beeswax SHD fuse. (225usd value)
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 KitsuneTuned 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 3 weeks production time and will adjust as orders come in. We never discount our KTE model, however this one and only time we will offer a preorder price of 100usd off msrp!
Prices are as follows for Spring2 lineup:
L1 = 1698usd +shipping
L2 1998 + shipping
KTE 2698 + shipping
Thank you for your support and understanding!
– 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.
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. Other places ONLY offer two models. Below are the three models:
Holo Spring 2 base model – LEVEL 1
(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)
Holo Spring 2 “Rise Ji Edition” – LEVEL 2
(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.
Holo Spring 2 “Kitsune Tuned Edition” – no compromise version
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.
Kitsune’s 99.99% Pure Silver O-Type Precision Tuned Transformer (exclusive to Kitsune Hifi) Notice in photo that the bottom transformer is a 240V Australian model. (two 120V pri)
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..
Spring’s input and output interface:
- Digital input interface includes
- USB (ground isolation)
- RCA coaxial
- BNC coaxial
- 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.
Spring 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).
(spring1 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 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.
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.
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.
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.