Welcome for worldwide customers

Product Description:

This new DAC “Spring3” is the design that has been very popular since 2016.  This is another 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. Trickle down technology from the Flagship May Dac. The Spring3 is here to achieve new heights, new dynamics and simply a full spectrum of audio to please the aural senses.

Features:

• A new generation of linear compensation technology. A better solution to the resistance, accuracy errors caused by switching components and PCB, after compensations makes the equivalent accuracy reach 0.00005%.
• The new generation of de-glitch technology can provide a full range without increasing the noise floor or other adverse effects.
• Based on this new generation of technology, “泉3” Spring3 (non preamp model) can provide a SINAD of >112dB and a dynamic range of >128dB, which represents the performance limit reached by today’s most advanced R2R architecture DAC.
• Using the ultimate performance of PLL+FIFO technology, provides 0.1Hz Third-Order low-pass ability to inhibit jitter. It also uses a high-performance femtosecond VCXO as the PLL clock source. Under the premise of being almost immune to the front-end jitter, it can also lock up to 1.5us-2us @ 1KHz signal with high jitter. (It can lock up to 1.5us-2us @ 1kHz signal with high jitter on the premise of almost being immune front-end jitter).
• The USB interface uses proprietary firmware with ultra-low latency, a highly reliable data transmission, ideal USB eye pattern measurements that contributes to 2-4 times higher performance than official firmware.
• A single, independent HDMI-I2S input interface is provided, which has a four-way independent circuit, as opposed to standard LVDS chip, making I2S clock signals subject to lower interference and lower jitter. In addition, the I2S input can be configured with a specific pinout configuration, making it compatible with most of the HDMI-I2S digital devices on the market.
• Optional (Factory installed only): A fully balanced, fully discrete analog pre-amplifier. Provides 84 steps, each step is 1db of volume control.

Specifications

L1

(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, round wire type copper wiring. Considered the base model however packs a mean punch for price per dollar performance ratio. (no remote control in this version)

L2

(With HoloAudio 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. ) It has standard Red label 5N Copper Otype Transformer, round wire type copper wiring. 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.

L3 (same as KTE version in US)

on top of L2 spec:

OPTIONAL upgrade – Preamp Module – Fully discrete and balanced relay controlled volume control. Controls all the digital inputs volume with precision. This has trickle down technology from our popular flagship Preamp the Serene. Using 4 amp modules and hundreds of transistors.

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

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.

Spring3 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 2.9 Vrms for single ended output and 5.8 Vrms for balanced output (dsd playback is half these voltages). 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. 

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).

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.

What are the Spring 3’s sound characteristics? :