Language English 






Safety Warnings ▼

Chapter 1   Product Introduction and Features ▼

Chapter 2   Key Features and Product Contents ▼

Key Features
Product Contents


Chapter 3   Identifying the Parts and Descriptions ▼

Front Panel
Rear Panel


Chapter 4   Product Installation ▼

Windows 7 / 8 / 8.1 / 10
Windows XP
Mac OS X


Chapter 5   How to Use Diagram ▼

Product Connection Diagrams
Connecting Methods to Mobile Devices (to an iPad or a smaprtphone)


Chapter 6   Setting of Gain Jumpers for Headphone Output ▼

Chapter 7   Cautions for Replacing Op-amp ▼

Chapter 8   Specifications ▼

Guide to Customer Service ▼








Safety Warnings ▼



You should read this document before using this product in order to use it safely.












Product Introduction and Features ▼


• Outline and Features of HUD-mx2 (Hi-Fi USB Audio DAC)
With the objective of developing a product that realizes the best hi-fi sound quality, enhances user convenience, has diversified connectivity, and has most functionality relative to the price while not emphasizing on a fancy exterior and demanding specifications, the development of the HUD-mx2 has been completed after a long period of time, adopting a number of high-quality components and utilizing our company`s extraordinary PCB design technology. The HUD-mx2 is capable of processing an optical input (24bits/192kHz) and a USB input (24bits/96 kHz) using only USB bus-power and enables users to enjoy audio playback that offers stronger sound output and higher sound quality by connecting the adaptor provided with the product. Moreover, users can enjoy audio playback from an iPad (with a camera kit) or a smartphone (with an OTG cable) that supports the new USB audio, etc. by connecting to them. Because it supports automatic power on/off and a power saving mode, the HUD-mx2 maximizes user convenience and power efficiency when using the product in the USB input mode.    


• 24bit/192kHz High-Quality Sound Playback
Adopting the newest Vinyl EnvyUSB 2.0 Audio Controller from VIA, high-quality sounds with a maximum 24bits/96kHz from a USB input and 24bits/192kHz from the optical input can be played back with no loss of quality from the sound sources. Additionally, with the embedded PCM1796, a high-performance DAC offering a 123dB dynamic range from Ti, the HUD-mx2 demonstrates high-resolution sound quality and hi-fi audio quality.   


• Mounting of Highest Level Op-amp and High-performance Headphone Amplifier 
Because the I/V converter and filter circuits are designed into the DAC output terminal, strictly conforming to the standard Ti design and mounting LME49860, a highest grade op-amp from National Semiconductor and OPA2227 and OPA2134 from Ti are placed at the optimum positions to produce the best sound quality, successfully realizing the high-performance and high-fidelity audio sound with the optimum balance and very low sound distortion as well as ultra-low noise. Additionally, the mounting of TPA6120A2, a high-fidelity headphone amplifier from Ti, allows users to use headphones with impedance values under 300Ω when using it in the factory default state and enjoy sounds with enough volume from the headphones with high impedance values of 600Ω after removing the gain jumpers (JP1 and JP2) inside the main body of the product. The high-quality audio signals generated through a number of highest level components can be transmitted to a speaker, an earphone or a headphone, providing users with a hi-fi level sound environment. 


• Embedded High-performance, Ultra-low-noise LDO Regulator and Inverter on the Power Source 
A simultaneous supply of positive and negative voltages is necessary to activate the dual-power-type high-performance op-amp. This enables the creation of the highest level of abundant and high-density analogue signals that can be generated from hi-fi sound equipments by supplying a positive voltage to the op-amp circuits through a high-performance inverter circuit after undergoing a rectification process that converts the supplied power from the USB port or an adaptor to high and stable quality, noiseless power through a high-quality LDO regulator and a low-ESR capacitor.   


• Activation of the Protection Circuit When Making a Connection or Disconnection of the Adaptor  
The normal procedure to use the adaptor is make a connection to the USB port after making a connection of the adaptor, but it does not go out of order if this procedure is not followed since a protective circuit is embedded. It is normal to hear a distorted sound temporarily when you connect or disconnect the adaptor during use, since the distorted sound is a phenomena occurring when the protective circuit operates. 


• Automatic Power On/Off and Power Saving Function
Because this product is designed to automatically turn the power on or off when the computer power is turned on or off or enters the power-saving mode when it is used in the USB input mode, it maximizes user convenience and the efficiency of power usage.     


• Supporting of USB Bus-Power
Without the adaptor, this product can be operated only with USB power in most computing environments. However according to the system when the voltage of the USB port is low, a little noise can occur. So please don't turn up the Windows Volume to the max, it is recommended to set the Windows Volume to about 80%. Also normal operation may not be possible when using a powerless USB hub under unstable power conditions, with some notebooks, or with low-power computers. In such cases, the adaptor must be used when connecting to an iPad or a smartphone before use. Also, users who use a headphone with impedance values over 150Ω have to use the adaptor to use the HUD-mx2 to get the maximum sound output.


• Can be connected to an iPad (with a camera connection kit) or a smartphone (with an OTG cable) that supports the USB audio


• Adopts a high purity TCXO for the clock generator in the USB controller


• Adopts a high-performance ALPS potentiometer and the highest grade aluminum knob for the front panel volume controller 


• Adopts a high level film capacitor from WIMA in the low-pass filter area


• Adopts total eight dedicated regulators and a number of high-performance low-ESRs and tantalum capacitors in main parts for stable and high-quality power supply 


• Adopts high-performance solid capacitors having super low-ESR & high ripple current in the DAC`s power side 


• Adopts highest grade metal film registers from Vishay-Dale normally used for high-end audio equipments 


• Quipped with the DDC function that converts USB digital audio signals to S/PDIF (optical TX) output 


• Supports 88.2kHz signals that most USB audio DACs do not support


• Embedded with an anti-pop circuit to eliminate unnecessary noise when the power is turned on or off  








Key Features and Product Contents ▼


Key Features 

Interface 1 : USB1.1 & USB2.0 Full Speed compliant (Max 24bit/96kHz)
Interface 2 : S/PDIF Optical on TOS-LINK (Max 24bit/192kHz)
Resolution/Sampling rate : 16/24bit, 44.1/48.0/88.2/96.0/176.4/192.0kHz
Digital Audio Receiver : AK4113(24bit/192kHz, Low Jitter Analog PLL)
D/A Converter : PCM1796(24bit/192kHz, 123dB SNR, Advanced Segment)
Headphone Out : Stereo phone & Stereo mini (16∼600Ω)
Line Out : Unbalanced RCA
Digital Out (S/PDIF) : Optical (Max 24bit/96kHz)
OPAMP : LME49860(SMDx2), OPA2227(DIP), OPA2134(DIP)
HeadPhone Amplifier : TPA6120A2(SMD)
Operating Systems : Windows XP / Vista / 7 / 8 / 8.1 / 10, Mac OS X
Dimensions (mm) / Weight(g) : 100(W) x 120(D) x 29(H) / 260g
Power Supply : USB Bus Power or DC Adapter(12~15V)


Product Contents

● HUD-mx2 main body   
● USB cable (USB A to B type USB cable, 1.5M)
● RCA cable (1.5M)
● Bumpon (anti-slippery, anti-vibrating rubber foot made of polyurethane
● Hexagon wrench (for attaching and detaching the volume knob) 
● Power adaptor (DC 12V~15V)

※ A program/driver installation CD is not included in the product content. The above product content may be changed without notice for enhancing product functions. 









Identifying the Parts and Descriptions ▼










①& ② Headphone/Earphone (6.35Ø Stereo Phone Jack / 3.5Ø Stereo Mini Jack)
A headphone or an earphone can be connected with a 6.35Ø or a 3.5Ø jack.

※ When connecting a headphone, connect it while minimizing the volume if possible. Be careful since there is a risk of a product malfunction, if a device other than a headphone is connected to it. 


③ Output Toggle Switch (abbreviated as ‘Output Switch’)
A desired output can be selected. The switch can be pushed up when using headphones and pushed down when using the line out. 


④ Input Toggle & Off Switch (abbreviated as ‘Input Switch’)
A desired input can be selected or the HUD-mx2’s operation can be stopped. The switch can be pushed up when using an optical input’ and pushed it down when using a USB input. If the input switch is set to OFF position during the device operation, sound output stops and the indicator lamp goes off in about five seconds.  
※ When the input switch is set to OFF position, the device enters the maximum power saving mode and the USB connection is maintained as it is. 


⑤ Active Indicator
●Red → Unlock  ●Orange → Lock (Standby)   ●Green → Active (Play)  ●OFF → Power OFF


⑥ Volume Controller (Potentiometer)
This component adjusts the headphone or the line-out output level.
※ Due to the nature of analogue volume, it is recommended to set the knob’s volume to over 25% (“9 o’clock”) at least.
※ When using the device with USB power, the headphone output starts to be distorted if the volume knob surpasses about “two o’clock” on the maximum volume setting in Windows. Therefore, it is recommended to use the adaptor when you use a headphone with high impedance values  (about over 150Ω). 















⑦ Optical IN (S/PDIF Optical Input, Pink Shutter) 
It is possible to use a PCM signal input by connecting to an audio device (CDP, DDC, etc.) with an optical output function. This supports sampling rates of 44.1, 48.0, 88.2, 96.0, 176.4 and 192.0 kHz.


※ When connected to a PC by using the USB connector, the PCM signal input via the Optical IN is controlled by the master volume setting in Windows (device name: Audinst HUD-mx2). Therefore, besides the volume adjustment using the volume control on the front of the main body, volume of the optical input signals can be controlled by using the volume control keys on a multimedia keyboard and the mute function. (As long as the adaptor power is connected, the volume value can be maintained as it is after the power is turned off or the USB cable is disconnected. It operates at the maximum volume when only the Optical IN is used without connecting the USB cable from the first.)  
※ Since the HUD-mx2 is not a decoder, Dolby Digital or non-PCM signals in DTS format cannot be used as input signals. 


⑧ Optical Out (S/PDIF Optical Output, Grey Shutter) 
It is possible to use a PCM output. It is used after connecting it to the receiver amplifier having an optical input function by using an optical cable.  
※ A driver to use AC3 pass-through function is activated on the hompage, you can set it on the player.

⑨ USB Port
This port is used to connect the HUD-mx2 with a PC by using the USB A to B cable.


⑩ DC Jack
This is used to connect to the DC 12~15V power adaptor provided with the HUD-mx2.
※ Make sure to use the HUD-mx2 after connecting the adaptor when using a system having unstable USB power such as netbooks, laptop PCs or mobile devices or using the optical input only.


⑪ RCA Line Out
This is used to connect the HUD-mx2 to the speaker by using the RCA cable. 
※ You must use the HUD-mx2 after connecting a speaker without an amplifier (passive type) to an amplifier. 












Product Installation ▼



• Product Installation [ Windows 7 / 8 / 8.1 / 10 ]
When the HUD-mx2 is connected to a USB port on a PC, the device is automatically recognized, and Windows Basic USB Audio Driver is installed.
After the [Speaker Audinst HUD-mx2] is automatically registered by following Control Panel → Sound →  Playback, the audio can be outputted immediately. 






When using an AV receiver having an optical input function, a PCM digital output can be used through the Optical Out terminal after setting the Sound Playback Output Device to the [SPDIF Interface Audinst HUD-mx2].  






※ AC3(Dolby Digital) / DTS pass-through can be supported by getting the driver provided on our website. 
※ A PCM digital output can also be supported by setting the Sound Playback Output Device to the [Speaker Audinst HUD-mx2].



• Product Installation  [ Windows XP ]
When the HUD-mx2 is connected to a USB port on a PC, the device is automatically recognized and Windows Basic USB Audio Driver is installed. After the Audinst HUD-mx2 is registered by following Control Panel → Sound and Audio Devices, audio can be outputted immediately. 


• Volume Setting in the Windows Volume Mixer
Regarding to the sound quality, it is advantageous to set the sound volume to the maximum in the Windows Volume Mixer. But, when you use an earphone or a headphone with low impedance values, it is recommended to use the device after finding proper sound volume through adjusting the sound volume in the Windows Volume Mixer and through Analogue Volume Adjuster.    







• Product Installation  [ Mac OS X ]
An installation of a separate driver is not needed and users can immediately use the HUD-mx2 after connecting to a USB port on a PC and the USB audio device is recognized automatically. The HUD-mx2 is automatically registered by following the System Environment Settings → Sound Device List. 





Users can change sample format, beat quality, etc. on the Audio MIDI Settings as below. 













How to Use Diagram ▼














• How to Make a Connection to an iPad  
※The adaptor must be connected to the product. By using an iPad camera connection kit, users can use iPads with HUD-mx2. 








• How to Make a Connection to a Smartphone  
※The adaptor must be connected to the product.
An Android device (i.e., Galaxy S3, Galaxy Note2) that supports ‘Jelly Bean’ operating system and an USB OTG (On-To-Go) cable can be used by connecting the cable to the HUD-mx2 as below.














Setting of Gain Jumpers for Headphone Output ▼



• Setting of Headphone Output Gain Jumpers (JP1, JP2)
Users can change the output gains of the HUD-mx2 according to the impedance of the headphone used. As a part of factory default settings, the jumper caps are all inserted into both the JP1 and JP2 jumper pins. The headphone output gain is increased by 1.5 times by removing the two jumper caps that correspond to the right and left channels. 



















Cautions for Replacing Op-amp ▼


Since replaceable-socket-type OPA2227 and OPA2134 from Ti are installed in the HUD-mx2, users can replace the op-amp according to the taste of music. To replace an op-amp, first remove the volume knob by using the hexagonal wrench provided with the product, and separate the PCB from the case by slightly pulling out the RCA jack. Then, remove the installed op-amp and install a new op-amp into the blank socket so that the op-amp is in line with the direction of the groove area on the socket.    





Caution: Replace an op-amp after removing the cable connections between the HUD-mx2 and the DC adapter as well as the USB cable. And confirm the installation direction of the op-amp, check if the op-amp is a usable type and has an operating voltage.   


• When replacing an op-amp, pay close attention to the installation direction. Please pay close attention when you install an op-amp since you may not get free warranty service in case product damage or other functional problem occurs due to the installation of a wrong type op-amp or erroneous installation such as reverse mounting or bad mounting.


• Types of op-amps usable for the HUD-mx2: DIP Type & Dual Type(Stereo) op-amps (An SMD-type one can be used after conversion to a DIP-type one and a single-type one can be used after conversion to a dual-type one.)

• The operating voltage of an op-amp is generally described as maximum and minimum operating voltages on the datasheet on the manufacturer’s website. The HUD-mx2 supplies ±12V to the op-amp circuits when the adaptor is used and ±5V when USB bus-power is used. Install the op-amp after checking if these voltages are between the maximum and minimum operating voltages of the op-amp. 

Ex.) LME49860 : Operating Voltage ±2.5V to ±22V  →  Usable
MUSES01 : Operating Voltage ±9V to ±16V      →  Usable with the adaptor
MUSES02 : Operating Voltage ±3.5V to ±16V   →  Usable









Specifications ▼
















Guide to Customer Service ▼



Warranty period is 2 years from the date of purchase.


• Receipt of the product tells the date of purchase, and if it is impossible to check the date of purchase from the receipt, the date of purchase is regarded as the same date with that of manufacture.


• Free repair would be accepted only in case of breakdowns during normal use of the product under warranty. Even if the product is under warranty, repair for the product would be charged when the product is damaged by natural disasters(lighting, fire, immersion, and so on), is modified, and is damaged and broken down by user’s careless behaviors and faults.


• If the product breaks down under warranty, you can use mail or delivery service in order to get free repair or you can visit our Customer Service Center yourself for free repair.


• For more inquiries and technical supports for the product, please visit Audinst website to use customer board or contact us for consultation.


• Customer Service Center
#801-1 Jooan Sibeom Gongdan, 17-1, Jooan-Dong, Nam-Gu, Incheon, Korea









본 설명서는 (주)오딘스트가 모든 저작권을 가지므로 내용 중 일부라도 복제하는 것은 금지되어 있습니다. 본 설명서에 기록된 제품의 성능이나 사용방법은 제품의 성능 향상을 위해 예고 없이 변경될 수 있습니다.
● 홈페이지 :
● 고객지원센터 : 인천광역시 남구 주염로 58 (주안동, 주안시범공단공장동 801-1호)



Since only Audinst Inc. holds the copyright, this manual may not be copied or photocopied, in whole or in part.  In order to improve performance, the contents of this manual including the capabilities and the ways to use the product is subject to change without notice.


本書の著作権は Audinst Inc. に帰属します。本書の一部あるいは全部を Audinst Inc. から書面による事前の許諾を得ることなく複写複製(コピー)することを禁じます。本書に表示された製品の機能または規格は、性能向上のために予告なしに変更されることがあります。


B급 기기(가정용 방송통신기기)
이 기기는 가정용으로 전자파 적합 등록을 한 기기로써 주로 가정에서 사용하는 것을 목적으로 하며, 모든지역에서 사용할 수 있습니다.





1. 기기의 명칭(모델명) : HUD-mx2
2. 인증번호 : KCC-REM-Ast-HUD-mx2
3. 인증자 상호 : (주)오딘스트
4. 제조자/제조국가: (주)오딘스트 / 한국



● Microsoft, Windows 및 Vista, 7, 8, 8.1, 10은 미국 또는 기타국가에서 Microsoft Corporation의 등록상표 또는 상표입니다.
● Macintosh, Mac OS 및 iPod, iPad 는 Apple Inc.의 상표입니다.
● 본 설명서에 기재된 모든 다른 상표명은 해당 회사의 상표 또는 등록 상표입니다.



FCC Statement

Note: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in acco rdance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures: 


ㆍReorient or relocate the receiving antenna. 
ㆍIncrease the separation between the equipment and receiver. 
ㆍConnect the equipment into an outlet on a circuit different from that to which the receiver is connected. 
ㆍConsult the dealer or an experienced radio/TV technician for help. 


Modifications not expressly approved by the manufacturer could void the user's authority to operated the equipment under FCC rules.