Our demo unit. Less than 1 year old and in very good condition. A very good DAC and headphone amp that we recommend!
The UD-505 is a
flagship dual monaural USB DAC with an integrated fully-balanced
headphone amplifier, that fuses high-end audio design concepts and
TEAC's decades of audio design experience, in an A4-sized footprint.
its predecessor models, the UD-501 and UD-503, it employs a dual
monaural circuit design to process audio signals with even greater
purity, with the latest VERITA AK4497 DAC chip used on each of the two
channels. This improves the S/N (signal to noise) ratio by processing
each channel individually in monaural mode, as well as delivering DSD512
(22.5MHz) native and 768kHz/32-bit PCM playback capabilities.
analogue section, which is one of the keys to sound quality, includes
four TEAC-HCLD buffer amp circuits process different drive modes, -
fully-balanced drive for balanced output, and parallel drive mode for
unbalance output, - to achieve enhanced acoustic expressive.
headphone section is remarkable. A totally new 4.4mm headphone jack,
called Pentaconn, is employed, allowing balanced and active ground
connections within a single jack, while conventional 1/4" phone jacks
are also provided. In addition to a wide range of digital and analogue
inputs, a Bluetooth® receiver supporting LDAC™ and Qualcomm® aptX HD™
allows you to enjoy high-quality wireless audio streaming from your
smartphone on this flagship USB DAC.
The UD-505 is a compact and high-spec USB DAC and headphone amplifier that supports today's high sampling rate Hi-Res formats.
Hi-Res audio playback supporting DSD512 (22.6MHz) and PCM 768kHz/32-bit PCM
Dual monaural circuit design with a high-end AKM VERITA AK4497 DAC on each channel
5 types of PCM digital filters and 2 types of DSD digital filters
Up-conversion up to 24.5MHz DSD and 384kHz/32-bit PCM
Dual on-board clocks for 44.1kHz and 48kHz frequencies, and 10MHz external clock input
Bluetooth? receiver supporting LDAC? and Qualcomm? aptX? HD
TEAC-HCLD output buffer circuit and TEAC-QVCS volume control for high quality sound
4.4mm 5-polar Pentaconn jack and dual 1/4" TRS jacks for balanced and active-ground drives *1
TEAC's patent registered pin-point feet in three positions for the perfect installation *2
"Bulk Pet" USB transfer technology, with four transfer modes to vary sound character *3
Free TEAC HR Audio Player for DSD512 and PCM32/768 playback
USB audio port for Hi-Res audio input from Windows/Mac
Coaxial and optical digital inputs on both front and back
Convenient analogue LINE input to use the UD-505 as a pre-amplifier
Analogue outputs with balanced XLR and conventional unbalanced RCA outputs
High-contrast full-graphic organic EL display with dimmer
Full-metal body with an A4-sized footprint
Free TEAC HR Audio Player for DSD512 and PCM32/768 playback
Compliant with RoHS
*1 "Pentaconn" is a registered trademark of NIPPON DICS Co., Ltd., complies with the RC-8141C JEITA standard
*2 Japan patent No. 4075477 and No. 3778108
*3 "Bulk Pet" is a registered trademark of Interface Corporation.
High-performance VERITA AK4497 DACs supporting DSD512 and PCM32/768
UD-505 employs the latest VERITA AK4497 (developed by Asahi Kasei
Microdevices) on each of the left and right channels. It is a
highly-regarded high-end audio DAC, and supports DSD512 (22.5MHz) and
768kHz/32-bit PCM formats, achieving industry-leading ultra low
distortion levels. OSRD (Over-sampling Ratio Doubler) technology,
meanwhile, significantly reduces out-of-band noise. As a result, the
UD-505 has the refinement necessary to make the most of Hi-Res formats,
successfully processing information that lies outside the audible range.
The AK4497 is the flagship product of the Asahi Kasei Microdevices
Audio4pro™ family, which has been developed for professional audio
equipment and high-end digital audio.
Dual monaural circuit design and fully-balanced design
dual monaural circuit configuration is used throughout, from the power
supply (including power transformers), to the D/A converters in the
digital section and the analogue output stage. From the high-performance
VERITA AK4497 D/A converters to the massive toroidal-core power
transformers, each element is configured for single channel processing.
This prevents mutual interference effects while reproducing a rich
In addition, the analogue audio signals of
both the left and right channels are processed in full balanced mode
soon after the D/A converters all the way to the output terminal,
contributing to an improved S/N ratio and extended dynamic range. This
allows the fantastic sense of air that Hi-Res formats possess to be
processed and conveyed without any losses.
High-quality wireless audio streaming via Bluetooth®
addition to conventional SBC and AAC codecs, the UD-505 also supports
LDAC™ (24/96 Hi-Res audio transmission), and Qualcomm® aptX™ HD, a codec
that uses 24/48 format transmission. These allow you to playback
playlists on your smartphone and tablet wirelessly.
Dual on-board clocks for 44.1k and 48kHz, and external clock input
of referencing to an unstable and noisy PC clock during USB audio
playback, a more accurate and on-board clock is generated by a
high-precision, low phase-noise, audio-grade crystal oscillator for USB
asynchronous transfer mode. The UD-505 accommodates two on-board clocks
exclusively for 44.1kHz and 48kHz sampling frequencies and applies the
appropriate one to incoming digital signals - those that are multiples
of 44.1k or 48k - to reproduce identical sound to the original by
eliminating jitter effects on the audio signal.
In addition, an
external 10MHz clock input is also provided, to synchronise with an even
higher-precision master clock generator, such as the TEAC CG-10M, for
yet further upgraded audio playback with excellent sound quality.
Up-conversion up to 384kHz/32-bit PCM and 24.5MHz DSD
RDOT-NEO (Refined Digital Output Technology NEO), a fluency algorithm
that renders digital audio signals smoothly, the UD-505 up-converts PCM
digital signals up to 384kHz/32-bit PCM and 24.5MHz DSD. With the
up-conversion function activated, you will hear an improvement in
quality, even with music that you are familiar with.
"Bulk Pet" USB transfer technology for enhanced audio quality
transferring large volumes of digital data for Hi-Res audio sources
through USB cables using conventional isochronous transfer mode, large
variations can occur in the processing loads of the sending computer and
the receiving USB DAC. This can cause sound to drop out and other
problems to occur.
However, with our new USB transmission
technology - dubbed "Bulk Pet" - a fixed amount of data is transmitted
constantly, levelling out the processing burden on both devices and
contributing to stable data transmission. Changing the processing burden
on the computer directly affects audio quality so users can select the
setting they prefer (from four transmission modes).
*"Bulk Pet" is a registered trademark of Interface Corporation.
For more information about "Bulk Pet," please visit the Interface Corporation website.
More digital filters than previous model
the UD-505, there are two types of DSD filters and another five types
of PCM digital filters, allowing you to apply the filter that best
matches the file format or type of music you're listening to. The filter
can be changed at the touch of a button on the remote control, allowing
you to enjoy the different sonic nuances of each filter.
PCM digital filters
Sharp Roll Off: FIR filter with a steep roll-off that sharply cuts signals outside the audio band
Slow Roll Off: FIR filter with a slow roll-off that gently cuts signals outside the audio band
Short Delay - Sharp: Short delay filter with a steep roll-off that sharply cuts signals outside the audio band
Short Delay - Slow: Short delay filter with a slow roll-off that gently cuts signals outside the audio band
Low Dispersion: Short delay filter with low dispersion that cuts signals outside the audio band.
receiving signals at 352.8 kHz, 384 kHz or higher, the digital filter
will be disabled during processing regardless of the above setting.
DSD digital filter
Narrow: Cut-off frequency of 39kHz (at 2.8M), 78kHz (at 5.6M), 156kHz (at 11.2M) or 312kHz (at 22.5M)
Wide: Cut-off frequency of 76kHz (at 2.8M), 152kHz (at 5.6M), 304kHz (at 11.2M) or 608kHz (at 22.5M)
Isolated digital and analogue sections
order to suppress interference between the digital and analogue
sections, the UD-505 employs an independent power supply and ground
circuit, so eliminating cross-interference in the signal path where
digital and analogue sections connect. A digital isolator is employed at
the input section to eliminate noise originating from any connected
digital sources, including noise that is generated from the computer via
USB, power line and the ground path. This isolation circuit also makes a
significant improvement in the signal-to-noise ratio as well as the
final sound quality.
Dual high-capacity toroidal-core power transformers
dual monaural theme continues. Two over-sized high-capacity
toroidal-core power transformers are employed in the UD-505, supplying
stable, individual current sources for each of the left and right
channels. This means neither channel will be affected by changes in the
power consumption of the other during digital processing.
Unique TEAC-HCLD output buffer amp circuits
the heart of analogue section are TEAC-HCLD (High Current Line Driver)
buffer amp circuits, designed to enhance current supply. Each channel
employs two identical buffer amps that process differential drive for
balanced output, and parallel drive for unbalanced output. By increasing
the current supply to the buffer amp section, the analogue audio signal
is passed to the next step without any loss of dynamism.
TEAC-QVCS high-precision volume control with four circuits
UD-505 is also a superb pre-amplifier, thanks to its combination of
outstanding analogue processing performance, a wide range of
analogue/digital inputs, and fixed/variable level XLR (balanced) and RCA
(unbalanced) outputs. These allow you to build a fully-fledged hi-fi
system around the UD-505 with a stereo amplifier/pair of monaural power
amplifiers and floorstanding speakers, or a simplified system based on a
pair of active speakers
The TEAC-QVCS (Quad Volume Control
System) is a precise volume control design incorporated in the pre-amp
section. This circuit employs four sets of variable gain-amps
controlling volume for left, right, positive and negative (L+, L-, R+,
R-). Each variable gain-amp is located on a simplified signal path which
helps eliminate interference noise by creating a shorter signal path.
addition, the TEAC-QVCS provides precise volume control in 0.5dB steps
in 'dB' display mode, or 100 steps in 'step' display mode.
Full-dot OLED display with excellent visibility
high contrast full-dot OLED (organic EL display) with 4-step dimmer is
employed, for excellent visibility. Even better, a highly legible, large
font size allows you to easily verify the volume level, input source
and other information, even when sat at a distance.
Discrete circuit design with balanced drive
UD-505's headphone amplifier circuit provides balanced-drive by using
the TEAC-HCLD circuit, - comprised of four output transistors for each
left and right channel - for headphone output. Furthermore, by driving
these transistors in parallel when a single-ended headphone is
connected, the UD-505 delivers stronger driving power than most ordinary
single-ended headphone amps provide. When listening to conventional
headphones, it also operates in Class-A (by expanding the Class-A range
of operation), despite using a Class-A/B amplifier.
challenging 600Ω high-impedance headphones for example, the UD-505
allows you to bring out the potential of these type of headphones.
Pentaconn, a totally new single-plug connector for balanced headphone drive
addition to the dual conventional 1/4" TRS jacks for balanced
connection, the UD-505 employs a newly designed single headphone jack
for balanced drive. The Pentaconn jack is a new 4.4mm 5-pole jack that
has been developed by NIPPON DICS Co., Ltd, and complies the RC-8141C
JEITA Standard, providing a single-jack solution for balanced
headphones. More Pentaconn jack-equipped headphones and cables are
expected in the near future.
Along with the Pentaconn jack, two
1/4"� TRS jacks provide three driving modes: balanced, active-ground,
and parallel drive (for two pairs of single-ended headphones).
*"�Pentaconn"� is a registered trademark of NIPPON DICS Co., Ltd.
Active-ground drive offers a new headphone drive mode
active-ground is a new driving mode that employs the principles of
balanced connection. It forcefully drives the ground, by lowering the
ground level to 0V, providing an ideal ground condition (rather than
just connecting to the conventional ground) This means it also
suppresses hum noise from the power supply and enhances the purity of
silent pauses by lowering the noise floor. Subtle detail, such as the
breathing of artists and the textures of sounds, will feel even more
Full-metal body for functionality and beauty
as with the successful Reference 503 series, the UD-505 employs
aluminum-alloy panels - including iconic side guard-bars - and a robust
metal chassis with a compact A4-size footprint* that completely matches
with the 500 series and the new CG-10M master clock generator. The full
metal construction isn't just beautiful, it's also functional. It's
highly effective at isolating the internal circuits from electromagnetic
*Not including connectors, knobs and other protruding parts.
Symmetrically laid out XLR and RCA output jacks
UD-505 is equipped with both balanced and unbalanced analogue audio
outputs. A pair of XLR connectors and another pair of RCA connectors -
each gold-plated - are symmetrically laid out, hinting at the dual
monaural arrangement inside, and allowing a wide range of possible audio
configurations. A wide-spaced pitch layout for the RCA outputs
accommodates professional grade plugs with large-diameter shells. The
UD-505 has a total of 5 digital inputs: USB audio, coaxial, optical on
the rear panel, and a combination jack on the front panel (for coaxial
and optical, supporting PCM 24/192 and DSD64 in DoP format).
of RCA analogue audio input connectors allow the UD-505 to function as a
pre-amplifier equipped with a high quality and precision volume control
Three-position, patent-registered 'Pin-Point' feet for perfect stability
UD-505 employs TEAC's patented 'Pin-Point' feet. These ingeniously
comprises two separated metal sections in a in an integrated housing.
One is has a spiked top and is attached to the bottom of the chassis,
the other is a basin-shaped base that hangs down from the spiked section
with a flange-shaped cup to simply installation.
'Pin-Point' foot are used for support, two at the front and one at the
rear, for excellent stability, even on an uneven floor.
result, the three 'Pin-Point' feet help improve the accuracy of clock
oscillation by minimising vibrations and resonance. This, in turn,
reduces mid and low frequency muddiness, improves the soundstage and
enhances fine sound detail.
* Patent numbers 4075477 and 3778108
Free TEAC HR Audio Player software for DSD512 playback on both Windows and Mac
next-generation Hi-Res formats, DSD512 (22.5MHz) and PCM 768kHz/32-bit
are supported via the TEAC HR Audio Player software for Windows and Mac.
This software guarantees the best available playback quality with any
combinations of audio format and computer configurations via a single
USB cable. All the user has to do is choose the UD-505 from the
pull-down menu showing target output devices.The TEAC HR Audio Player is
available from TEAC's web site, and is completely free to use.
*Use on a Windows computer requires a free driver, also provided by TEAC.