HERUS is an asynchronous USB Audio 2.0, 24bit 352.8Ks/S, DXD and DSD64/128, 2.4VRMS Headphone DAC. The perfect companion to anyone who enjoys music, the HERUS fits perfectly in your laptop bag or pocket, and replaces the functionality of the soundcard normally found in a laptop or desktop computer. HERUS+ is an advanced HERUS design that adds a low power mode and selectable oversampling filters. HERUS+ runs longer on your cell-phone battery and sounds even better than the HERUS when playing conventional 44.1 and 48k music because it offers customized up-sampling filters.

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HERUS+ is our smallest form-factor, audiophile quality USB to Headphone DAC. It uses the USB Audio 2.0 Asynchronous protocol and supports DSD64 and DSD128 as well as high data rate PCM at 24bits up to 352.8Ks/S.

It is a USB powered device that achieves more than 100dB of SNR, (typically 108dB) and is capable of driving 2.4V RMS, (ie 6.8V pk-to-pk) into headphones from 600 Ohms to 32 Ohms. The distortion in all cases is better than 0.005% (85dB): the measured THD+N is typically 89dB for 32 Ohms and 90dB (about 0.003%) for 600 Ohms. HERUS+ has a low power mode and the ability to select advanced up-sampling filters.

1 year parts and labour. (Detailed Warranty information may be found under the “HERUS” menu item on every page).

HERUS+ will enumerate to the controlling computer and register itself as being able to handle volume control internally. BlueIPhoneAlmost all music player applications will then send control commands to the HERUS+ which it will use within the ES9010-2M DAC chip to implement high performance 32 bit volume control processing. This is significantly better than the volume control implemented in the music player software. HERUS+ is easy to use: plug HERUS+ into a USB 2.0 (ie High Speed port) [with USB+ Audio 2.0 enabled if on MS Windows] and select HERUS+ as the output device in your system control panel. That is all there is to it… IMPORTANT: Please note: some (if not all) software on the PC, MAC and Linux will, the first time HERUS+ is connected, set the volume to 0dB. That is, to the highest volume level. This may be very loud in the headphones. On subsequent connections the music player application will recall the last volume setting, but we have seen instances where plugging into a different USB port again sets the volume back to 0dB. Consequently, we strongly recommend that you plug the HERUS+ into any new port on your computer with the headphones unplugged, and set the volume to a reasonable level prior to plugging the headphones into HERUS. Additional note:  The volume level may rest to full volume if the headphones are swapped out while music is playing – please pause the music while you swap headphones when using HERUS+. For more details see this FAQ note. You may, if you wish, use HERUS+ as other than a headphone driving DAC. For example, when driving a power amplifier you will find that HERUS+ is a capable and high performance system component. It is perhaps the optimum and lowest cost solution to accessing DSD music from your computer collection. Please read our FAQ on this question for more information.
The total distortion (THD) on any HERUS will always be better than 85dB (ie less than 0.005% distortion) and the noise (SNR) will always be better than 100db, typically 108dB. More detailed specifications are:
Asynchronous USB Audio 2.0 PCM bit width 24 or 16 Bits (If provided with 24bits HERUS uses them all, but it works with 16 bits also)
Supported Data Rates 44.1, 48, 88.2, 96, 176.4, 192 and 352.8 Ks/S
Supported Formats PCM, DXD and DSD64/128 Uses DoP protocol 1.1 over USB for DSD
Operating Systems MS Windows, MAC OS and Linux Use the Resonessence Thesycon Driver for USB Audio 2.0 on Windows
Output Signal Level At Maximum Volume level 2.4 VRMS
Output Impedance 0.2 Ohms
SNR at least 100 dB, Typically 108dB
THD at least 85 dB, Typically 90dB
Power Into 32 Ohms 126 mW
THD + N 0.0035 (89) % (dB) Typical
Power Into 60 Ohms 95 mW
THD + N 0.0032 (90) % (dB) Typical
Power Into 300 Ohms 19 mW
THD + N 0.0032 (90) % (dB) Typical
Power Into 600 Ohms 9.5 mW
THD + N 0.0032 (90) % (dB) Typical

Thesycon Asynchronous USB Audio 2.0 Windows Driver

Updated Windows 10 Driver – July 2016 – This new driver works for Windows 7 8 and 10. Follow the general outline documented below but use Version 3.34 from this ResonessenceUSBAudioDriver_DriverSetup_v3.34.0_Win7_8_10 zip  file. (Note: we have had reports of ‘distortion’ or other artifacts from earlier versions – this V3.34 is the latest provided to us from Thesycon)

Overview (November 2014 – Version 2.16 – HERUS+ support)

Resonessence is pleased to provide at no charge, the Thesycon Resonessence specific driver which will allow our customers to use USB Audio 2.0 with our products on the Windows operating system. The Apple operating systems already include USB Audio 2.0 and no special driver is needed. Resonessence INVICTA provides both USB Audio 1.0 and USB Audio 2.0 and is switchable between the two under user control, or by automatic detection of the host capabilities. Please note that a USB Audio 2.0 driver is shipped with every INVICTA unit on the provided SDCard. Use this driver for your INVICTA product – installation instructions are in Appendix A of the User Guide. However, Resonessence CONCERO and HERUS only operate in Async. USB Audio 2.0 mode, and so require a third party driver on the Windows operating system. Follow the instructions below to download the Resonessence generic USB Audio 2.0 driver that supports all our products. Please note: earlier versions of the driver only supported the INVICTA product, this driver supports all Resonessence products. Please uninstall any older Resonessesence driver before installing this latest one.

Downloading and Installing the Thesycon USB Audio 2.0 Driver for Windows

1 Download this zip file: ResonessenceUSBAudioDriver_DriverSetup_v3.34.0_Win7_8_10 and unzip the contents into a temporary directory on your computer 2 Plug the Resonessence device into a High Speed (USB 2.0) port of your PC. In step four below the installer will query the device. In the case of the INVICTA/MIRUS the device will need to be in USB2.0 mode. To do this press the left of the four buttons, rotate to “INVICTA Options”, press the rotary knob, rotate to “USB Speed” press the rotary knob, rotate to “USB 2.0” press the rotary knob. Press the left button, rotate to USB Audio 2.0, press the rotary knob.
3 Run the “setup.exe” file in the directory: one 4 Follow the instructions to ensure the device is plugged in and then choose “Next”: twoMost Frequently asked question at this step: Note: on INVICTA ensure that a) USB is selected as the audio source and b) USB Audio 2.0 is selected in the user options. [See note 2 above]
5 Install the Driver Software: four 6 Continue to choose “Next” when appropriate, and the installation will complete after a short while: nine
7 At this point the driver software is in place, ready to be found by Windows. The next time Windows sees the device connected it will install the Thesycon USB Audio 2.0 driver.  To use the newly installed driver, select the Resonessence product in the Sounds “Manage Devices” control panel. Windows thereafter will direct digital audio over the USB Audio 2.0.
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Returning the HERUS for Repair under Warranty

If you find any problems, faults or unexpected performance in the HERUS unit in the first year of operation, it may well be covered by our warranty policy. The first step in returning a unit to Resonessence is to contact your local dealer, or directly by phone to us at our Canadian headquarters (778) 477-5536. We are in the North America Pacific Coast time zone and the country code for international calls is (1). You may also email to support@resonessence.com. Please be prepared to provide the unit serial number when requesting support and be sure to include it in any Email. Resonessence is pleased to provide a one year warranty under the terms described below, but reserves the right to determine whether the warranty applies in each specific case. We will attempt to determine if the warranty is applicable in the initial contact you make with us or our dealers, but it may be necessary to return the unit for inspection to make the determination. All returned items require a Return Materials Authorization (RMA) number which you will receive from us along with the shipping address to which the unit should be returned. Please mark the shipping box with the RMA clearly visible on the outside. We can only accept units for return or repair with the RMA attached. By shipping a unit to us you agree to the terms and conditions of our repair and return policy, outlined below. LIMITED WARRANTY Subject to the conditions set forth below, for one year after the original purchase date of the unit (unless otherwise specified), Resonessence will repair, or if necessary replace, the unit at no additional cost, in the event of a defect in materials or workmanship of the hardware elements of the unit. This warranty is extended only to an original purchaser of the unit from an authorized reseller or directly from Resonessence. We do not provide a warranty of any kind if the unit has been purchased from an unrecognized or unauthorized reseller. We may request proof of purchase prior to providing any warranty service. We may, at our discretion, not extend the warranty to units used as rental units by a third party business if not approved by Resonessence or our authorized dealers. This warranty only covers failures due to defects in materials or workmanship in the hardware elements of the system. Damages incurred in shipping, or due to accident, inappropriate use of the unit or power surges of any kind are not covered. Alterations to the unit undertaken by unauthorized individuals or organizations are not covered. Damage incurred during attempted reverse engineering, design data extraction or attempted internal measurements of any kind are specifically excluded from any warranty. Installation of any unapproved software, or external algorithms of any kind designed to expose or debug the operation of the unit, or to circumvent or otherwise interfere with the unit’s unique identity code, causing damage or thereby erasing the unit’s operating system or similar, are not covered by any warranty. THIS LIMITED WARRANTY GIVES YOU SPECIFIC LEGAL RIGHTS. YOU MAY HAVE OTHERS WHICH VARY FROM STATE/JURISDICTION TO STATE/JURISDICTION. REPAIRS MADE UNDER WARRANTY Resonessence will be responsible for all parts and labour necessary to fix defects in materials or workmanship of the hardware elements of the unit. NON-WARRANTY REPAIRS ETC. Resonessence will charge for a minimum two hours of work at the prevailing hourly rate, plus all shipping costs, for any unit returned that does not qualify for the warranty service, or is returned for upgrade, technical audit or software re-initialization. Upon receipt of the unit, we will inform you of the estimated cost of the work and await your approval to proceed. Note that in all cases, even if you do not agree to the additional work, you will be responsible for the minimum two hours and shipping costs. Parts and labour costs incurred to complete non-warranty work, even in the case where they exceed our estimate, will be your responsibility. REPLACED, REPAIRED OR UPGRADED PARTS Any parts repaired or replaced either under warranty or as a paid service, are themselves warranted against defects in materials or workmanship for one year after the service date. Parts not replaced or repaired remain on the initial warranty schedule. SHIPPING If a unit covered by warranty needs servicing during the first 30 days after the original purchase date, Resonessence will cover the cost of shipping the unit back, as well as the return shipping to you. After this initial 30 day period, and for one year after the original purchase date, Resonessence will only cover the cost of shipping the unit back to you, and you are responsible for the cost of shipping the unit to Resonessence. You are responsible for all shipping costs both to and from Resonessence for non-warranty work. You are responsible for paying all taxes, import duties, or similar fees imposed by foreign countries or other jurisdictions. LIMITS AND EXCLUSIONS RESONESSENCE DOES NOT, BY VIRTUE OF THIS DOCUMENT, OR BY ANY COURSE OF PERFORMANCE, COURSE OF DEALING, OR USAGE OF TRADE, MAKE ANY OTHER WARRANTIES, EXPRESS OR IMPLIED, INCLUDING, WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE OR NONINFRINGEMENT, AND ALL SUCH WARRANTIES ARE HEREBY EXPRESSLY DISCLAIMED. RESONESSENCE EXPRESSLY DISCLAIMS ANY IMPLIED INDEMNITIES. RESONESSENCE SHALL NOT BE LIABLE FOR ANY INDIRECT, INCIDENTAL, CONSEQUENTIAL, PUNITIVE, SPECIAL OR EXEMPLARY LOSSES OR DAMAGES, INCLUDING, WITHOUT LIMITATION, DAMAGES TO RECORDINGS, DATA STORAGE DEVICES, TAPES, DISKS, DAMAGES FOR LOSS OF BUSINESS PROFITS, BUSINESS INTERRUPTION, LOSS OF BUSINESS INFORMATION, LOSS OF GOODWILL, COVER, OR OTHER PECUNIARY LOSS, ARISING OUT OF OR RELATING TO THE USE OF ANY PRODUCT, OR ARISING FROM BREACH OF WARRANTY OR CONTRACT, NEGLIGENCE, OR ANY OTHER LEGAL THEORY, EVEN IF RESONESSENCE HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH LOSSES OR DAMAGES. ANY DAMAGES THAT RESONESSENCE IS REQUIRED TO PAY FOR ANY PURPOSE WHATSOEVER SHALL NOT EXCEED THE ORIGINAL COST PAID TO RESONESSENCE FOR THE APPLICABLE UNIT. BECAUSE SOME STATES/JURISDICTIONS DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES, THE FOREGOING LIMITATION MAY NOT APPLY TO YOU.