Audiobyte HYDRA-X reference USB interface

World first exclusive:

Asynchronous , fully isolated, battery powered, 384 KHz PCM/5.6 Mhz DSD reference USB interface 

In my latest review I tested YBA Passion 650 with different digital sources, but in the end mainly with Lampizator Level 4 DAC and new Audiobyte HYDRA-X - Asynchronous, fully isolated, battery powered, 384 KHz PCM/5.6 Mhz DSD reference USB interface. With this combination things are finally moving positively in the digital domain through my perception. Audiobyte HYDRA-X locks with my solid-state drive based MacBook Air instantly and exclusive in what is called access mode, direct mode and most importantly integer mode. Hydra supports integer directly and when connected everything else regarding audio on Mac is idle. Yes, it shouts out everything regarding audio. You cannot even start a quick time movie. Why is this so important? Firstly in years I could hear the results instantly and with the large pace through digital front end. Everything was present as raw and directly at my face.

I’m still hard-core analogue fan, but things are finally getting into the right direction with digital. I’m always listen about how much precision, knowledge and tuning is needed on the analog side. Well, It “ain’t” any different on the shores of digital Audio Ocean. Hydra X from Audiobyte is a big and better step into make things easier to integrate with DAC’s.

Stay tuned for in depth review in due time and in depth interview with Nucu Jitariu. And to keep you minds at peek, Silver Dragon DAC is coming for a review.

This is seriously loaded interface. Check out technical aspects and specifications and you’ll quickly understand what I’m talking about.


Asynchronous , fully isolated, battery powered, 384 KHz PCM/5.6 Mhz DSD  reference USB interface 

Either if you love your current setup and don’t want to change your DAC ,or just want to upgrade your current usb interface, the Hydra-X is the perfect way to add (or improve) computer based playback on your system.

The Hydra-X(treme) was designed as the ultimate USB interface in terms of both objective and subjective performance. Built around the latest generation of FPGA technology, the goal of the design was to produce stunning sound and to offer the highest definition available for a commercial product.

To achieve this goals some key factors are defining the Hydra design :
1.     The ultra high-speed usb interface, capable of very high audio sample rates. The Hydra is equipped with a modern ARM processor for resolving usb transactions.

2.   The isolation between noisy PC environment and the audio chain. The USB isolation for audio devices is nothing but tricky. If you choose to use usb isolators, then sample rate will become limited, which is not an option. If you choose to isolate the output, you are adding significant amounts of jitter to the signal. By using a clever circuit topology, the Hydra design avoids these two bottlenecks. The isolation is placed between the ARM processor and the FPGA audio core, therefore not limiting the banwidth. Being before the clocks, it’s jitter contribution becomes irrelevant.

3.    The Spartan6 FPGA is the heart of the Hydra. This advanced programmable circuit is offering a bit-transparent processing and signal conditioning to S/PDIF, AES/EBU, Toslink and I2S outputs. It also gives the ability of the Hydra to output raw dsd audio streams.

4.     The clocks – unlike other products which only specify “low jitter clocks” , we are saying the exact type of what we’re using: it’s the CCHD-957 type from Crystek, one of 45.1584 Mhz and one of 49.152 Mhz. You can check real graphs of these ultra-low phase noise clocks here[link]. The clocks are system masters. In order to remove any jitter induced by the FPGA circuit itself, special retiming is applied just before the Hydra outputs.

5.    The battery – a low impedance, LiPo-nano technology , provide to the system the cleanest power supply needed for pristine audio performance. All sensitive circutry like the clocks, FPGA and retiming circuitry benefit from battery power. The USB port and external (optional) are alternative options for powering the system, but everything was primarily designed to work with clean battery power.

6.     Careful pcb layout is often neglected in the rush of getting a product quickly into the market. The Hydra-X design time took many months until everything came close to perfection, until the shortest routing paths, the best decoupling places, the less interference and crosstalk placement for the components are found.

Technical specifications:

Input :
USB receptacle, type B high-speed
Output :
1)     S/PDIF, 75 ohm coaxial
2)     AES/EBU, 110 ohm XLR
3)     Toslink
4)     I2S over HDMI (LVDS)
Supported sample rates, pcm:
1)     44.1 KHz
2)     48 KHz
3)     88.2 KHz
4)     96 KHz
5)     176.4 KHz
6)     192 KHz
7)     352.8 KHz
8)     384 KHz
Supported rates, dsd:
1)     2.8 MHz (DSD64)
2)     5.6 MHz (DSD128)
Bit depth:
1)     32 bit over I2S output
2)     24 bit over S/PDIF, AES/EBU, Toslink
Compatibility :
1)     Native MacOS 10.6 and later
2)     Native Linux with UAC2 compliant kernel
3)     WASAPI, KS, DS drivers for Win XP to W8 32/64 bit
4)     Recommended players : Foobar2000, Audirvana Plus, Jriver18 etc.
General specification:
1)     Power consumption : 0.37 W
2)     Battery cycle : 2 hrs. charging/5 hrs. playback
3)     Dimensions : 125 x 105 x 60 mm
4)     Weight : aprox. 0.8 kg

Matej Isak. Mono and Stereo ultra high end audio magazine. All rights reserved. 2006-2013. ..:: None of the original text, pictures, that were taken by me, links or my original files can be re-printed or used in any way without prior permission! ::..