Ferrum FULL Headphone Stack at Vinyl Sound Buffalo, New York

The Ferrum FULL Headphone Stack is a complete three-component desktop headphone system from Ferrum Audio (Warsaw, Poland), available at Vinyl Sound in Buffalo, New York. The bundle combines the WANDLA DAC/preamplifier, the OOR fully balanced headphone amplifier, and the HYPSOS Hybrid Power System into a unified, triple-EISA-Award-winning ecosystem engineered for the most demanding headphone listening. Across the three units, headline figures include 130 dB dynamic range (A-weighted) from the OOR, ESS Sabre ES9038PRO DAC resolution up to 768 kHz/32-bit and DSD 256 in the WANDLA, and a programmable DC output voltage range of 5 to 30 V from the HYPSOS. All three components share an identical chassis footprint of 217.5 x 206.5 x 50 mm, stacking neatly on any desk and connecting internally via Ferrum's proprietary Ferrum Power Link (FPL) cable for optimised power delivery and deepened feedback sensing between units.

WANDLA: Reference DAC and Preamplifier

The WANDLA is built around the ESS Sabre ES9038PRO chip and operates in fully balanced mode throughout. It accepts digital sources via USB-C (up to 768 kHz/32-bit and DSD 256), I2S (PS Audio compatible), AES/EBU, coaxial S/PDIF, optical S/PDIF, and HDMI ARC with CEC control for home theatre integration. Analogue input via RCA with a 47 kΩ input impedance completes the source roster. The DAC section delivers THD of 0.00009% (-121 dB) and a dynamic range of 127 dB (A-weighted), while the balanced XLR output reaches 9.3 V RMS at 0 dBFS. Volume control operates in either fully analogue mode (with bypass option) or digitally for DAC operation, giving users flexibility across both headphone and loudspeaker system configurations. Four proprietary Signalyst HQ Player filters ship alongside the standard ESS filters, allowing listeners to tailor the DAC's digital reconstruction to their preference. MQA decoding and rendering is supported across all digital inputs. Power consumption is 10 W idle, rising to 15 W maximum, and the WANDLA accepts both its included 24 VDC adapter and the proprietary four-pin FPL connector from the HYPSOS.

OOR: Fully Balanced Discrete Headphone Amplifier

The OOR is a purely analogue, fully discrete, fully balanced headphone amplifier with no integrated circuits in its signal path. On the balanced output, it delivers 1,600 mW into 300 Ω and 8 W into 60 Ω, with THD of 0.00011% at 1 mW into 50 Ω. The dynamic range measures 130 dB (A-weighted), and output impedance at the headphone jack is below 0.3 Ω. Gain is selectable in three steps: -4/+6/+16 dB balanced, and -10/0/+10 dB single-ended, accommodating both sensitive in-ear monitors and high-impedance planar magnetic headphones. Inputs are balanced XLR and unbalanced RCA, with both a 4-pin balanced XLR headphone output and a standard 6.35 mm single-ended jack. Frequency response extends from 20 Hz to 100 kHz within 0.1 dB. When connected to the HYPSOS via FPL cable, the HYPSOS senses voltage directly at the OOR's internal rails and continuously corrects delivery in real time, a capability not available via any standard DC connection.

HYPSOS: Hybrid Power System

The HYPSOS combines linear and switching power supply topologies in a single compact chassis. Its output voltage is continuously adjustable from 5 to 30 V, covering a wide range of audio components beyond the Ferrum family. The proprietary 4T Sensing Design (4TSD) measures voltage at the load rather than at the supply output, compensating for cable resistance and ensuring flat voltage delivery regardless of current draw. A Sweet Spot Tuning function allows fine-grained voltage adjustment to identify the precise operating point at which a connected device performs best. Maximum continuous output power is 80 W for voltages above 13.3 V, and maximum impulse current reaches 9 A (270 W peak at 30 V). The HYPSOS also includes trigger input and output for system automation and is compatible with Apple TV remote control for voltage adjustment. A two-stage EMI filter on the IEC C14 mains inlet provides low-noise operation suited to analogue-adjacent applications.

Key Features

• Triple EISA Award Pedigree: HYPSOS won EISA Best Product 2021-2022, OOR won EISA Best Headphone Amplifier 2022-2023, and WANDLA won EISA Best DAC 2023-2024, making this the only complete headphone stack where every component has independently won audio's most prestigious industry award.
• Ferrum Power Link (FPL) Integration: Proprietary four-pin DC cable carries both power and sensing signals between the HYPSOS and the OOR/WANDLA, enabling the HYPSOS to regulate voltage at the load rather than at the supply output for audibly superior power delivery.
• ESS Sabre ES9038PRO with Signalyst Filters: The WANDLA uses the flagship ESS chip paired with four proprietary HQ Player filters developed exclusively for Ferrum, alongside the standard ESS filter set, giving users genuine control over digital reconstruction.
• Fully Discrete, Fully Balanced OOR Amplifier: The OOR uses no integrated circuits in its amplification stage. Output power of 8 W into 60 Ω balanced and dynamic range of 130 dB (A-weighted) place it among the most capable desktop headphone amplifiers available.
• Universal HYPSOS Voltage Range: The 5 to 30 V adjustable output with 4T Sensing is compatible with hundreds of third-party audio components, future-proofing the power supply investment beyond the Ferrum ecosystem.
• Complete Source Compatibility in WANDLA: Seven digital inputs including USB-C, I2S, AES/EBU, coaxial, optical, and HDMI ARC, plus analogue RCA, cover every source topology from computer audio to broadcast to home theatre.
• Matched Industrial Design: All three units share identical 217.5 x 206.5 x 50 mm chassis dimensions, stacking flush and sharing a coherent brushed aluminium aesthetic suited to professional and audiophile desktop environments.
• MQA Full Decoder and Renderer: The WANDLA decodes and renders MQA on all digital inputs, preserving investments in existing MQA libraries while remaining fully functional for all standard PCM and DSD formats.
• Selectable Gain on OOR: Three gain settings per input mode allow the OOR to drive IEMs without noise floor issues and high-impedance planar magnetics to full output, from a single amplifier chassis.

Technical Specifications

Connections at a Glance

• WANDLA digital inputs: USB-C, I2S (PS Audio compatible), AES/EBU, Coaxial S/PDIF, Optical S/PDIF, HDMI ARC with CEC
• WANDLA analogue input: RCA
• WANDLA analogue outputs: Balanced XLR, Unbalanced RCA (line output to OOR or external amplifier)
• OOR headphone outputs: 4-pin balanced XLR, 6.35 mm single-ended jack
• OOR inputs: Balanced XLR, Unbalanced RCA
• HYPSOS DC output: 5.5 x 2.5 mm or 5.5 x 2.1 mm plug; proprietary 4-pin FPL connector to OOR and WANDLA
• HYPSOS mains: IEC C14 inlet (100-240 V AC compatible)
• HYPSOS automation: Trigger input and output; Apple TV remote compatible

Awards and Critical Recognition

• EISA Best Product 2021-2022: Ferrum HYPSOS (Expert Imaging and Sound Association)
• EISA Best Headphone Amplifier 2022-2023: Ferrum OOR (Expert Imaging and Sound Association)
• EISA Best DAC 2023-2024: Ferrum WANDLA (Expert Imaging and Sound Association)
• Headfonia Best Amplifier 2024: Ferrum OOR, Readers' Choice Award (Headfonia)
• Headfonics 2024 Top Gear Award: Ferrum WANDLA GoldenSound Edition (Headfonics)

Frequently Asked Questions

What is the Ferrum FULL Headphone Stack?

The Ferrum FULL Headphone Stack is a complete desktop headphone system comprising three separate components: the WANDLA DAC and preamplifier, the OOR fully balanced discrete headphone amplifier, and the HYPSOS Hybrid Power System, all manufactured by Ferrum Audio in Warsaw, Poland. Each unit occupies an identical 217.5 x 206.5 x 50 mm chassis and connects to the others via proprietary Ferrum Power Link cables. Every component in the stack has independently won an EISA Award in its category, making this a triple-award-winning system available at Vinyl Sound in Buffalo, New York.

How does the Ferrum FULL Stack compare to the Chord Electronics Hugo TT 2 and DAVE?

The Ferrum FULL Stack and Chord Electronics DAVE + Hugo TT 2 represent two different engineering philosophies for flagship desktop headphone systems. Chord's approach centres on proprietary FPGA-based digital processing using Robert Watts' WTA filter algorithm, with no off-the-shelf DAC chip and a single-box-per-function architecture. The Ferrum stack uses the ESS Sabre ES9038PRO chip with four additional Signalyst HQ Player filters and separates the power supply into a dedicated chassis to provide cleaner, sensing-corrected DC to both the DAC and amplifier. The OOR delivers 8 W into 60 Ω balanced versus the Hugo TT 2's 1 W into 8 Ω, giving the Ferrum stack a substantial output power advantage for planar magnetic and high-impedance dynamic headphones. The Ferrum system also provides significantly more digital inputs, including HDMI ARC and I2S, and offers a fully variable analogue volume stage with bypass, giving it broader system integration flexibility.

How does the Ferrum OOR compare to the Benchmark HPA4 headphone amplifier?

The Ferrum OOR and Benchmark HPA4 are both fully balanced, low-distortion solid-state headphone amplifiers in the high-end desktop category. The Benchmark HPA4 uses a passive transformer-based volume control and is designed primarily as a reference measurement tool with a focus on vanishingly low noise figures. The OOR uses a fully discrete proprietary power amplifier topology with no integrated circuits and is specifically designed to benefit from external power conditioning via the HYPSOS FPL connection, a feature the HPA4 does not offer. The OOR's balanced output power of 8 W into 60 Ω exceeds the HPA4's output capability for low-impedance loads, and the OOR provides three switchable gain stages allowing it to serve both sensitive IEMs and demanding planar magnetic headphones from the same unit. The HYPSOS sensing connection elevates the OOR's measured noise floor and dynamic range beyond its already competitive standalone specifications.

What is the Ferrum Power Link (FPL) connection and why does it matter?

The Ferrum Power Link is a proprietary four-conductor DC cable that carries both the power supply voltage and a separate feedback sensing signal between the HYPSOS and the connected component. Standard DC cables deliver power only, meaning the supply regulates voltage at its own output terminals rather than at the actual load inside the amplifier or DAC. The FPL cable routes a sensing wire directly to the internal power rail of the OOR or WANDLA, allowing the HYPSOS to measure and correct voltage at the point of consumption rather than at the socket. This eliminates the voltage drop caused by cable resistance and enables real-time continuous correction of transient demands as the amplifier draws current during musical peaks. The audible result is tighter bass control, lower noise floor, and improved dynamic contrast compared to operating either the OOR or WANDLA on a standard power adapter.

Can the Ferrum WANDLA be used as a preamplifier to drive power amplifiers and loudspeakers?

Yes. The WANDLA functions as a fully featured preamplifier with variable output on both its balanced XLR and unbalanced RCA outputs, making it directly connectable to any power amplifier or active loudspeakers. Analogue volume control operates in a bypass mode for pass-through at unity gain, and digital volume control is available when operating the DAC section. The balanced XLR output reaches 9.3 V RMS at 0 dBFS, which is sufficient to drive virtually any power amplifier to full output. The analogue RCA input with 47 kΩ impedance also allows the WANDLA to serve as a preamp for non-digital sources such as phono preamplifiers. In a full Ferrum system, the WANDLA feeds the OOR headphone amplifier via XLR for headphone listening and can simultaneously output to speakers via the RCA outputs for a shared-source dual-use desktop configuration.

Which headphones pair best with the Ferrum OOR amplifier?

The OOR is designed to drive all headphone types from a single unit, thanks to its three selectable gain stages. High-impedance dynamic headphones such as the Sennheiser HD 800 S (300 Ω), Beyerdynamic T1 (600 Ω), and Audeze LCD-4 planar magnetics benefit most from the OOR's balanced output of 1,600 mW into 300 Ω, which delivers ample headroom and dynamic authority. The lowest gain settings (-4 dB balanced, -10 dB single-ended) make the OOR equally suited to sensitive IEMs without introducing audible noise floor. The output impedance below 0.3 Ω at the headphone jack ensures flat frequency response and damping factor is maintained regardless of headphone impedance curve. The OOR drives both the 4-pin XLR balanced format used by Audeze, ZMF, and Hifiman, and the standard 6.35 mm jack for single-ended operation.

Does the HYPSOS work with components from other brands besides Ferrum?

Yes. The HYPSOS is designed as a universal audiophile power supply with a continuously adjustable output from 5 to 30 V DC, making it compatible with a wide range of audio components that accept external DC power. Compatible devices include streamers, DACs, headphone amplifiers, phono preamplifiers, and network switches from numerous manufacturers. The 4T Sensing Design function is only active when using the proprietary FPL cable with Ferrum components, but standard DC operation via the 5.5 mm barrel connector is fully available for third-party devices. The adjustable voltage range and Sweet Spot Tuning function allow users to identify the optimal operating voltage for each connected device, which often differs from the manufacturer's nominal specification. Ferrum maintains a compatibility list on their website covering confirmed third-party products.

Where can I buy the Ferrum FULL Headphone Stack in Buffalo or Western New York?

The Ferrum FULL Headphone Stack is available at Vinyl Sound, an authorised Ferrum Audio dealer located in Buffalo, New York, serving customers across Western New York and the broader USA. Vinyl Sound stocks the full Ferrum Audio lineup and can provide hands-on demonstrations of the complete WANDLA, OOR, and HYPSOS stack. Customers in the Buffalo area can visit in store or contact Vinyl Sound directly to arrange a listening session or discuss configuration options including the HYPSOS Dual Output variant for powering both the OOR and WANDLA from a single unit.