Sign in to follow this  
Guest BD Audio

Audiobyte Hydra Z USB Bridge

Recommended Posts

Guest BD Audio

Now available from BD Audio, the Audiobyte Hydra Z Usb Bridge and the optional Hydra ZPM Power Supply.

In the past I tried various USB converters and found they offered very little or even no improvement over a Dacs built in or even a cheap ebay unit. Until now.

I was put on to the units by a good friend overseas. Sceptical but I thought I would try. On first listen, it blew me away. Absolutely amazing. It's easy to see why these units are being fitted in to hugely expensive Dacs around the world, the product fast gaining momentum. I could not do without them now.

I also have Audiobytes DSD Dac/Headphone pre amp here, more on that another time...

These units will be at the upcoming North West Hifi Show (Sunday 28th) and available for demonstration afterward.




Audiobyte Hydra Z – USB audio playback bridge and clock generator

The previous model of Hydra, the X+, has built its reputation based on excellent sound quality. From our perspective, it is time to move on, and offer a new interface, that we named usb audio playback bridge.

While raising the bar even more in sound quality and keeping the existing set of features precedently available, the new Hydra Z comes with a list of improvements that we’re happy to share. Among the changes are a complete redesign of the digital board, changes in the way the Hydra is powered, new output configuration, new chassis and many other refinements – please see below.

MORE FLEXIBLE The Hydra Z can be powered in 3 (three) ways :

Directly from USB

From an external, fixed 5Vdc/0.5-1A power supply

From the dedicated Hydra ZPM (Z-Power Module)

Furthermore features:

Extended number/type of outputs

Adjustable I2S output clock polarity, to match all HDMI/I2S/LVDS dacs available

Adjustable masterclock output on I2S (512xfs or 1024xfs)

Firmware upgrade over usb

DSD native / DoP / hi-quality PCM converted (selectable)

DXD native (I2S out) / 192k or 176.4k (spdif, aes, bnc out)

TECHNICAL IMPROVEMENTS Hydra Z benefits from all the qualities of the X+, and even more. New clocking scheme allows shutting down one of the two main oscillators when not in use. By reducing the mutual interference between clocks, better phase noise performance can be obtained. The power supply section was moved to a different chassis for best results.

WORDCLOCK and MASTERCLOCK OUTPUT The Hydra Z can be additionally used as a wordclock or masterclock generator through its dedicated BNC output. In total there are available 6 (six) outputs, including the low-jitter wordclock/masterclock output for direct synchronizing external d/a converters. The output wordclock is the sample clock (44.1KHz – 384 KHz) or 512xfs (22.5792 MHz or 24.576 MHz). The other 5(five) are : SPDIF Coaxial, SPDIF BNC, AES/EBU, I2S, TOSLINK.

IMPROVED CHASSIS The new Hydra has a full aluminium chassis, with a 10 mm thick front panel. All connectors are conveniently placed on the back panel.

ISOLATION A 5KV isolation barrier is used to prevent any leakage of the noise from PC to your sensitive audio system. 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 bandwidth. Being before the clocks, its jitter contribution becomes irrelevant.

ARM PROCESSING All USB audio transactions are made through a powerful ARM3 processor. Therefore Hydra Z supports any sample rate available (384k PCM, DSD128) while being future-proof for any extension.

FPGA TECHNOLOGY As all AUDIOBYTE digital products, the Hydra Z uses cutting edge, custom digital processing developed into a Xilinx Spartan6 field-programmable gate array. The fpga is the “heart” of the Hydra. This advanced programmable circuit is offering a bit-transparent processing and signal conditioning to all outputs. It also gives the ability of the Hydra to output raw dsd audio streams.

AUDIO GRADE CLOCKS Unlike other products which only specify “low jitter clocks”, here is exactly what you will find inside : 2xCCHD-950/957 type from Crystek. These are real audio grade clocks. You can check real graphs for them here. These clocks are system masters. In order to remove any jitter induced by the FPGA circuit itself, special retiming is applied just before the Hydra Z outputs.

COMPONENTS AND LAYOUT Careful PCB layout is often neglected in the rush of getting a product quickly into the market. The Hydra Z design time took lots of work until everything came into the right place, until the shortest routing paths, the best decoupling places, the less interference and crosstalk placement for the components are found. Selected quality components (active and passive) are used for guaranteed long-time performance.

EXTERNAL POWER SUPPLY For best results you can use the Hydra Z with the dedicated Hydra ZPM power supply.



Power consumption : 0,7W

Dimensions : 240 x 170 x 45MM

Weight : 1,2kg



USB receptacle, type B


S/PDIF, 75 ohm coaxial

AES/EBU, 110 ohm XLR

BNC 75 ohms

I2S over HDMI (LVDS)


Wordclock BNC

Supported Sample Rates


44.1 KHz

48 KHz

88.2 KHz

96 KHz

176.4 KHz

192 KHz

352.8 KHz

384 KHz


2.8 MHz (DSD64) – DoP, native

5.6 MHz (DSD128) – DoP, native

11.2 MHz (DSD256) – native (via ASIO)

22.5 MHz (DSD512) – native (via ASIO)

Bit Depth

32 bit over I2S output

24 bit over S/PDIF, AES/EBU, Toslink


Native MacOS 10.6 and later

Native Linux with UAC2 compliant kernel

ASIO, WASAPI, KS, DS drivers for Win XP to W8 32/64 bit

Recommended players : Foobar2000, Audirvana Plus, Jriver etc.

Share this post

Link to post
Share on other sites
Guest BD Audio

Inside the optional ZPM Power Supply.


Share this post

Link to post
Share on other sites
Guest BD Audio

I have another batch of Hydra arriving by the end of the week.

Share this post

Link to post
Share on other sites
Guest BD Audio

Try a Hydra Z in your system and if you can't hear a large increase in sound quality send it back for a no quibble refund.

Share this post

Link to post
Share on other sites
Guest BD Audio

Just received another large order of Hydra Z and ZPM today, back orders sent and fresh stocks ready to go!

Share this post

Link to post
Share on other sites
Guest BD Audio

A large delivery of Hydra Z and Hydra ZPM arrived on Friday and are ready to ship on free next day delivery service.

Hydra Z is £600, ZPM £450.

Order both together and claim a £100 discount so only £950 for the full setup Inc free shipping and on a no quibble home trial.

Edited by BD Audio

Share this post

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.