Head-Fi’er @Torq got his hands on the Level 3 version of the Holo Audio Spring DAC. See why he says “It’s the most musical and enjoyable NOS DAC that I’ve heard so far, and doesn’t give up anything on the technical side” by clicking here: Holo Audio Spring DAC Level 3
The spring dac was special for RMAF 2016 , we decided to promote and show off it’s beautiful design. As it’s exterior is quite elegant and sleek. The interior is something we are very proud of. The pcb is painstakingly designed with care and precision. This is part of how it measures so well with linearity. The left and right channel’s are perfectly mirror images of each other with exactly the same trace lengths and component placement. check out what we did to show this off… Customers are now asking us for this option, It “MIGHT” be available in our store, but the cost is yet to be determined. Likely will be 100usd for a full color, gloss laminated, with squeegee installation tool and shipping included. These are printed on a top of line Latex printer that is capable of 1200DPI resolution. print quality is excellent.
Full color stickers have also been made and can be sent on request with orders if we have in stock. All KitsuneTuned Edition items are exclusive to owners/buyers from KitsuneHiFi ONLY. We are HoloAudio USA and only offer to our direct customers exclusive VIP items for their special edition Dac.
our end results was a beautiful gloss laminated finish and high resolution image of it’s internal beauty. We are proud of this dac and all the materials that went into it. Each component is specially paired and all are factory authorized and tested. These are backed by Jeff Zhu and fully factory warrantied. This shows off the beautiful solid silver O-type transformer, our new wiring updates with 1.5mm solid silver wire, direct soldered to pcb with mundorf supremem 9.5% silver solder. also pure silver Oyaide faston connectors, Audio Horizon Platinum reference fuse.
Also we will be offering optional copper badging for some of our new product, check this out. we even got new business cards for RMAF.
Solid pure copper badging is actually for a few projects… one will be our new BendyHead Headphone stands, and the other will be optional badges for the spring dac. such as below. Pricing will vary from 10usd-20usd per badge.
Holo Audio USA and KitsuneHiFi was fortunate to make this event and we co exhibited with Headamp in the Canjam Tent! This was a WIN WIN for both of our companies as Headamp truly benefitted from our Kitsune Tuned Edition Spring dac just as much as we did from their World class amps. The Blue Hawaii SE (worlds finest electrostatic headphone amplifier) and the GSX-MK2 which is also considered one of the worlds finest SS headamps. Our customers were able to hear our dac with very transparent and revealing amplifiers. Many customers told us we had the best sound in show! that was definitely nice to hear this. Overall the results were very spectacular and we’d be doing this every year now! Our booth was tight and small yet very busy most of the time. Our listening station had a pair of LCD4, HE1000V2, MS Carbon, Prototype MS Electrostats, and the Stax 009. All serious summit fi gear. Our source was a simple basic Microsoft surface book. From there we used a kimber cable USB cable to our JCAT Isolator (intona industrial pcb), and from that we used the JCAT ISO cable to the Singxer SU-1 (one of our best selling products!) The singxer SU-1 was the transport that allowed us to use the HDMI i2s input of our spring dac. The HDMI i2s IMHO is the best possible input to use for optimum sound. Why do we use JCAT isolator? Well show conditions had poor power quality, let alone any laptop has a poor PSU, this was key to eliminate any ground issues with true galvanic isolation of power and data at FULL usb 2.0 480mbps. Honestly I won’t have any audio system without my Jcat Isolator, it’s simply more than subtle. In show conditions it really does help and we like to thank JCAT, one of our vendors. Check out their new USB Femto card, this thing is sweeeet. 😀 OK i’m doing too much product shout outs, but these companies deserve it. Singxer, for instance, is one company that has USB figured out and has developed a digital to digital convertor with spectacular results. Their SU-1 has femto clocks, Crytek 575, and multistage regulation of power, and the newest XU208 xmos chipset. We choose their DDC as the ideal pairing with the Spring Dac. It delivers slightly more detail and wider soundstage.
iFi is a brand new line of electronics with trickle-down technology licensed from AMR and aimed primarily at the future, Computer Audio generation. All iFi products boast Class A analogue circuitry with no DSP and the signal stays ‘Bit Perfect’ throughout.
How a product looks and performs matters, but so does its impact on the environment. That’s why nearly every iFi product and its packaging are made from highly recyclable materials like aluminum, paper, recycled plastic and why we refuse to use harmful toxins in our components. They do this to ensure that every product they release meets our environmental standards.
We’re so excited to share our new discovery with you we’re offering free shipping on everything iFi
Products we carry from iFi. Why we chose to carry the product…….
We chose to carry the Pro iCan because this amp has more performance bang for its buck on the market. It includes the option of Solid State output, Tube output, and a of Solid State AND Tube combo output. On paper, the measurements, are better than most amps on the market, in practice it lives up to it standards. We feel this is one of the best headphone amplifiers on the market today and would like to share it with you! Outputs include, balanced outputs, 4-Pin XLR, dual 3-Pin XLR, and 3.5 mm TRRS. The remaining outputs are a 3.5 mm TRS and two single ended 6.35 mm. Lastly, its future ready with an output for an electro-static module .
iFi has been hard at work on changing the notoriously unrecognizable unbalanced wave into a true Square Wave, to even out signal and reduce jitter and is what we audiophile enthusiasts appreciate. Bit Perfect audio ensures the audio signal remains unchanged handling 44.1 / 48 / 88.2 / 96 / 176.4 / 192kHz; 16 to 24 Bit, DSD/DoP, and even Dolby Digital and DTS. Galvanic isolation prevents noise contamination in the signal. To further reduce noise jitter and drift a large number of complete audio samples helps absorb variation in signal. With co-axial/optical input AND co-axial/optical output enabling compatibility with any and every product from mass market Apple TV to a transport audiophile DAC. Add that extra, included in box, iPower ‘quieter than battery’ 1uV noise floor adapter, and low power consumption what else could you ask for. <300 femto second crystal clock with a precision of 0.001Hz fine tunes the signal and limits drift.
Active Noise cancellation
Any noise in our power and signal inputs distorts the perfect sound quality we’ve put so much time, effort and money into achieving.
The following accessories include active noise cancellation based on military radar technology actively generating an identical signal in the opposite phase which neutralizes the sound providing a clean power supply signal. When measured, this drops noise by 100 times or 40 dB compared to the Common Noise Filter.
A laptop uses a switch mode power supply and this device filters the power, improving it to the level of a linear power supply, this is why we use it on our personal laptop and other mobile listening stations. This provides ultra clean, low noise power, with active noise cancellation, noticeably reducing the noise floor. Also this features a reversed polarity protection/notification light stopping power input preventing potential damage to your device. You can also improve your the performance of your existing power supply by adding this inline with a DC output cable.
iPower (5V, 9V, 12V and even 15V versions)
An ultra low noise floor DC adapter, 1uV compared to the average audiophile linear power supply which measures 20uV. We like to use these for powering devices such as USB modules, DACs, AMPs, DIY projects and other devices such as RPi (Raspberry Pi), Arduino, Microrendu, Logitech Squeezebox, Uptone Regen, Paul Pang USB card, etc.
Cleaning up the digital USB audio chain by reclocking, rebalancing and regenerating the USB transmission. Clean up your downstream DAC by restoring Signal level, reduce Jitter, reduce Common Mode noise, rebalance signal, impedance Matching. We use one of these in our Audio-gd NFB-28 it increases the resolution of the top end detail and removes some of the harshness that delta sigma chips are known for. Future ready for all present and future PCM/DSD/DXD formats – without restriction.
This is the “Level3” KitsuneTuned Spring Dac Above
This is the “Level2” Rise Ji Edition Spring Dac Above
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. We have recently been talked with a very talented engineer that is the brains behind Holo Audio. Jeff Zhu is the man behind the curtain and has impressed us with his knowledge and his newest line of products he offers. The Spring DAC is his newest product and is capable of DSD native on an R2R DAC! This spring is capable of DSD512 native and actually running on his bespoke discrete ladder DAC! This unique DAC is not your run of the mill DAC, it’s full of unique and well thought out designs and implementations. 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 R2R network for DSD! We will be offering the first Spring DAC’s in the USA and the Level 3/Kitsune Tuned edition is Exclusive to us. We won’t stock more than a few at a time, and the wait time is usually a few weeks.
You may be asking… well what is so special about this DAC? The first Discrete R2R dac with Linear compensation…what is this?
There’s an additional R2R ladder in the Spring, 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.
Here at Kitsune, we have three versions of the Spring DAC. Other places ONLY offer two models. Below are the three models:
Spring’s input and output interface:
- Digital input interface includes
- USB (ground isolation)
- RCA coaxial
- BNC coaxial
- optical fiber
- I2S (HDMI)
- All digital input interface supports DSD (DOP mode).
- Analog Output interface: single-ended, balanced.
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 1K 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.
Please take a closer look by clicking on the image to open in new window. Take note of the Linearity of this dac. And also take note of the THD level’s being ultra low along with the Signal to Noise Ratio being better than average in general, but remember this is a NOS Dac so it’s actually extremely good and definitely one of the best NOS dac on the market today!
Here are some more photos that also explain some details
We now have a working relationship with SingXer (http://www.singxer.com/) from Guangzhou China. We will be carrying several of their products to offer as a local distributor in the USA. Curently we are choosing to offer the Singxer SU-1 and the F1 usb module. We feel these are the best USB options on the market today and proudly will offer these to you at competitive pricing!
A little bit about SingXer:
Sound Electronics Co., Ltd. Guangzhou Shi current office located in a beautiful Panyu District, Guangzhou City. Shi electronic sound team was founded in 2011 , by several team members have many years of experience in the development of audio products, product managers and senior engineers.Since the team was established, within the audio industry to undertake a number of technical development projects, the development team has been the outcome of customer satisfaction and recognition.
The company develops high-performance audio products, audio products can undertake OEM, ODM projects. We have a strong development capability in terms of XMOS Audio, pioneered the development of the second generation XMOS xCORE-200 series processors, XMOS Audio optimized many of the underlying firmware. Meanwhile, in the above hardware architecture, there are some technical points independent development. Including the independent development of the system clock, independent development of digital phase-locked loop technology “SHDPLL”, I2S shaping, full isolation technology and so on.
and info on the products we carry from Singxer.
Singxer’s list of distributors – you’ll find KitsuneHiFi as the ONLY USA distributor.
(please note the silver model is new and to be released soon, we will carry a very limited amount of this color, please email us to ask about ordering this color)
SU-1 digital interface is Singxer team developed a high-performance USB digital audio interface, using the latest XMOS family and Xilinx high-performance CPLD / FPGA chip. SU-1 is the rare use femtosecond system clock digital interface, Crystek of two CCHD-957 SU-1 crystal is the ultimate output audio signal quality has laid a solid foundation. SU-1 digital input interface using a standard USB2.0 interface. SU-1 has a wealth of output interfaces, including coaxial RCA and BNC output S / PDIF, XLR balanced outputs AES / EBU, HDMI output IIS (including DSD ON and MUTE signals) and BNC WCLK word clock output.
SU-1 is the first machine we have developed equipment that is positioned in the high-end interface, is used mainly in the following three main technologies:
1, full isolation technology (ground isolation), the use of 150Mbps full-chip isolation, interference can be completely isolated from the PC;
2, source synchronous shaping technology and CPLD technology, I2S signal isolation after the re-shaping; thus eliminating the isolation chip to bring added jitter;
3, the independent development of the system clock, using CRYSTEK high-performance oscillator, low phase noise and low jitter.
1, SU-1 is the first using the XMOS latest xCORE-200 series of high-end USB digital interface products. New generation XMOS chip, using more advanced process technology, performance than the older U8 chip doubled, reaching 1000MIPS processing capabilities.
2 , it is known, the weight of the core is digital audio algorithms. Our team in the field of digital audio work for many years, at the same time get XMOS FAE support team, we conducted a number of technical improvements and optimization algorithms on the basis of the original firmware.
Each output interface supports sample rates:
176.4kHz, 192KHz, 352.8KHz, 384kHz[ Wherein I2S out support full sample rate , S / PDIF supports up to 192KHz]
DSD: 2.8 MHz (DSD64) – DoP,native
5.6 MHz (DSD128) – DoP,native
11.2 MHz (DSD256) – DoP,native[ Wherein I2S out support all DSD format , S / PDIF and AES / EBU support DSD64 DOP mode ]
位宽：最高32 bit over I2S output
最高24 bit over S/PDIF
Each interface electrical standards:
1 , the USB input socket is a standard USB-B type female, the USB power supply range 4.5V-5.1V ;
2 , the RCA connector outputs standard S / PDIF signal level is 550mV ( access standard load ), the output impedance of 75 ohms;
3, the power input is 220V AC, internal use RS importing adapter for power.
1 , carry out electricity as the mother of the acoustic design concept, pay attention to the power supply circuit design, high-performance, low noise and fast response of the LDO as the main power source. The entire board using multiple independent path LDO power supply, wherein the clock even partially adopted ADI ‘s ultra low noise LDO , in order to ensure the ultimate output performance laid a solid foundation.
2 , the PCB motherboard with 4 -layer circuit board design, ensure that you have full power and ground plane layer, using the method of high-speed digital design, signal integrity and power integrity of the entire board. The clock signal for special treatment, using package design and precise impedance control, thereby ensuring the signal quality and increase the clock anti-jamming capability. Input and output signals follow a standard design, especially USB high speed signals using a 90 ohm differential impedance control.
1, Windows XP, Windows 7, Windows 8; 32/64 bit, you need to install special drivers
2, Native MacOS 10.6 and later, using the system comes with drivers
3, Native Linux with UAC2 compliant kernel, using the system comes with drivers
4, Android OS 4.2 and above, the need to support OTG function.
I2S interface with HDMI output socket:
1. The level of 3.3V for the LVDS differential signals;
2. The output signal is muted, DSD ON signal, 5V power supply (low current);
3. The output signal mute, DSD ON signal can be modified according to customer needs, internal CPLD can define different output pins; the two signals can be output to any socket PIN13,14,15,16 pins.
and the F1