It has become a trend in the high-end headphone world to offer everything in a single component to maximize limited desk space and simplify the process; and that often includes the inclusion of a network streamer and phono pre-amplifier. Do headphone users need all of this additional circuitry — and does it compromise the overall sound quality? Products like the new TEAC HA-507 offer a different approach and those who require a DAC will need to consider something from the manufacturer or look elsewhere for the digital side of the equation.
TEAC HA-507
Although TEAC’s Reference 500 series includes UD models that combine both analog and digital features such as a DAC, the HA-507 forgoes all digital circuitry in favor of a pure-analog input/output solution for both its preamp and headphone amp functions.
Equipped with an extensive power supply circuit, the HA-507 offers a rather robust 6.7 watts per channel (from its balanced outputs) and an extremely wide frequency response. When connected to the TRDD 5 discrete DAC, model UD-507, you can create a headphone playback system with separate digital and analog sections.
The HA-507 can also be used as standalone analog preamplifier. When paired with a Reference 500 Series power amplifier, such as the AP-505, users can have a compact audio system that further enhances the quality of their loudspeaker listening experience.
Headphone Amplifier Section
The HA-507 incorporates a high power, wide range, low distortion headphone amplifier with a balanced/dual mono configuration. The headphone drive can output 6.7W + 6.7W (32Ω) via its balanced output.
Pro Tip: The HA-507’s Preamp pass-through function enables connection to a separate power amplifier for headphones.
Headphone output connection options (wired only) include two balanced outputs (XLR 4-pin x 1, 4.4 mm Pentaconn x 1, and two Unbalanced outputs ( 6.3 mm x 1, 3.5 mm x 1). Switchable high, medium, and low headphone output gain is provided.
Preamplifier Section
In addition to using the HA-507 as a dedicated analog headphone amplifier, it also incorporates a full preamplifier section incorporating a balanced/dual mono configuration supported by “TEAC-QVCS Advanced” with a super high precision, ladder resistor network.
Volume control is provided in 0.25dB increments and the lossless, long-life FET (Field Effect Transistor) input switching system does not include mechanical contacts.
The “TEAC-HCLD 2 (High Current Line Driver 2)” provides fast and powerful external amplifier drive capability.
As a preamplifier, inputs (XLR x 2, RCA x 2) are provided for connection of additional source devices, and outputs (XLR x 1, RCA x 1) are provided for connection to an external amplifier for powering speakers.
The outputs can also be used to connect the HA-507 to an external DAC-equipped preamplifier. It can also be connected to a pair of active loudspeakers such as the Acoustic Energy AE1.
Power Supply
In addition to headphone amplifier and preamplifier functions, the HA-507 incorporates two independent power supplies (one for audio circuits and one for control circuits). Large toroidal power transformers with separate left and right windings exclusive for audio circuits are included with 18,800 μF per channel dual-mono configuration and high-speed Schottky barrier diodes.
Exterior Design
The HA-507 incorporates an A4-size aluminum chassis suitable for both audio rack and desktop applications as well as a semi-floating 2.8mm thick aluminum top plate. Stressless metal feet with three-point provide placement flexibility which provides precise imaging and natural sound characteristics. The HA-507 has a fanless, efficient heat dissipation design.
Control
Control features include high-grade aluminum knobs with a patent-pending mechanism to prevent off-axis shaft movement, trigger in/through terminals, and a dedicated remote (RC-1340) in combination with motorized volume control.
Comparison
Here is a comparison between the analog-only HA-507 Headphone Amp/Preamp and UD-507 Analog/Digital Headphone Amp/Preamp/DAC.
HA-507 UD-507 Price $1,999.99 $2,099.99 Deceive Type Analog Headphone Amp and Analog Preamp Analog Headphone Amp and Analog/Digital Preamp/DAC USB DAC – TRDD5 x 1 (L/R) DSD Format Support – 22.5Mhz/32-bit Max PCM Format Support – 384kHz/32-bit Max Up-Conversion (Max) – PCM 384kHz/32-bit (2 fs, 4 fs, 8 fs) Dual Mono Yes Yes Current Buffer Circuit TEAC HCLD2 TEAC HCLD2 TEAC QVCS Circuit Yes Yes Line/Balanced Inputs Yes Yes Line/Balanced Outputs Yes Yes Line Parallel Unbalanced Outputs Yes Yes High Precision Dual Clock – Yes External Clock Input – Yes Preamp Function Yes – Analog only Yes – Bult Pet Transmission Line Output Level Switching Fixed (0db)
Fixed (+6dB)
Variable
Path Thru
OffFixed (0db)
Fixed (+6dB)
Variable
Path Thru
OffFront Digital Input – Yes (USB Type C) Analog Line Inputs 2 pairs (XLR, RCA) 2 pairs (XLR, RCA) Bluetooth Receiver – Yes Headphone Amplifier Circuit Yes Current Strengthing Circuit Headphone Output com nectors/Drive modes XLR 4-pin x 1 (Balanced, Active Ground)
4.4 mm 5 pole x 1 (Balanced, Active Ground)
Standard
6.3mm x1 (Unbalanced)
3.5 mm (1/8″) stereo mini x 1XLR 4-pin x 1 (Balanced, Active Ground)
4.4 mm 5 pole x 1 (Balanced, Active Ground)
Standard
6.3mm x1 (Unbalanced)Feet Stressless Foot v 2 Stressless Foot v 2 Remote Control Yes Yes Dimensions (WHD) 290 × 84.5 × 243.9 mm
11.5 × 3.4 × 9.6 inches290 × 85 × 249 mm
11.4 × 3.3 × 9.8 inchesWeight 4.6 kg / 10 1/4 lbs 4.9 kg / 10.8 lbs Finishes Black/Silver Black/Silver 
The Bottom Line
The TEAC HA-507 takes a different direction from the UD-500 series models. There is no DAC, Bluetooth, or other wireless connectivity. Instead, the HA-507 takes an all-analog approach from input to preamp output, and of course to its headphone output.
With no DAC and no digital audio inputs, your sources are limited out of the box. However, if you connect a source that has its own built-in DAC in combination with analog outputs, that would work to deliver digital sources to the HA-507.
One way this can be done is to pair the HA-507 with the TEAC UD-507, but you can also connect a media streamer with analog outputs to the HA-507 to listen to digital source content.
On can also connect a turntable and external phono pre-amplifier to the HA-507 to add vinyl playback to the system.
When connected to an external power amp, you can listen to music from speakers or you can take advantage of an increasing number of powered speakers which have their own built-in amps.
On the other hand, the HA-507 is pricey at $1,999, especially when you consider that less expensive options, such as the well-regarded Michael Fidler SPARTAN 30 ($600) or Schiit Audio Vali 3 ($149) may satisfy your analog-only needs, albeit without TEAC’s proprietary audio technology and more input/output flexibility.
Price & Availability
The HA-507 MSRP is $1999 (USA) / €1899 (EU) / £1899 (UK). It will be available for purchase with a Silver or Black finish starting January 2025 at TEACUSA.COM.
Find a local dealer at teac.jp/int. For more information, visit: teac.jp.
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