Gryphon Helios

Gryphon Helios Preamplifier

The Gryphon Helios is a dual-mono, pure Class A line preamplifier and the long-awaited successor to the legendary Gryphon Pandora. A two-chassis design pairing the preamplifier unit with the dedicated PSU 5 power supply, it draws on the Pandora's proven circuit heritage and incorporates engineering innovations developed for the Commander to deliver a fully balanced, zero-negative-feedback signal path with an exceptionally wide range of system integration options. Designed and manufactured in Denmark, the Helios is positioned as the most versatile preamplifier Gryphon has yet produced.

Heritage and Lineage

The Pandora served the Gryphon lineup for fourteen years following its 2012 introduction, a remarkably long residency that speaks to the strength of its circuit topology. The Helios inherits the Pandora's fundamental dual-mono Class A architecture and refines it with an entirely new ultra-low-noise dual JFET input stage, a development drawn from the engineering work behind the Commander. Where the Pandora established the standard, the Helios brings that standard forward with trickle-down technology from Gryphon's most ambitious preamplifier design to date.

Within the Gryphon preamplifier lineup, the Helios sits between the Essence integrated line and the Commander, offering a dedicated two-chassis line stage with modular expansion capability that the Commander level provides, at a more accessible entry point into the range. The Helios is also the first Gryphon product to introduce a new visual design language, marking a new chapter in the brand's aesthetic identity.

Circuit Architecture

The Helios signal path is fully balanced from input to output. Single-ended RCA sources are converted to balanced signal immediately upon entry via Gryphon's proprietary gold-plated RCA sockets, ensuring the entire amplification circuit operates in balanced mode regardless of source connectivity. Zero global negative feedback is maintained throughout, preserving the immediacy and dynamic integrity that Gryphon regards as fundamental to musical authenticity.

At the core of the Helios is a super-fast discrete Class A input buffer built on a new dual JFET topology, followed by a fully discrete balanced dual differential Class A line stage and a fast current-amplifying Class A output stage. DC servo coupling eliminates the need for coupling capacitors in the signal path. The power supply for all voltage amplification stages is fully regulated and extremely low noise, with local shunt regulators at each amplification stage providing additional noise suppression. Two separate custom-wound 65VA toroidal transformers, one per channel, feed an 83,000uF capacitor bank per channel, with separate power supplies for digital and individual left and right analog circuits. PCB-mounted sockets eliminate internal point-to-point wiring, shortening the signal path further.

Volume Control

The Helios uses an 85-step relay-based volume attenuator built on fixed precision resistors and ultra-low capacitance relays. This is a fully discrete, non-digital solution: signal passes through a very small number of relays selected for what Gryphon describes as sonic invisibility, with no active elements in the attenuation path. The relay switching can produce a faint click at some volume positions, which is a normal characteristic of this topology. The attenuator provides smooth, accurate control with individually adjustable per-input gain trim, channel balance, start-up volume, and a user-configurable maximum volume ceiling.

Connectivity and System Integration

The Helios offers five analog inputs: three balanced XLR and two single-ended RCA. Two balanced XLR outputs and one single-ended RCA output are provided, with a second balanced output enabling direct connection to a second power amplifier or a recording device without splitting. Input 3 (XLR) or Input 4 (RCA) can be dedicated as a fixed-level AV bypass input for seamless integration with a home theater processor. Each input can be individually named and level-matched. The Green Bias output connects directly to compatible Gryphon power amplifiers, allowing the preamplifier's volume position to automatically manage the amplifier's Class A bias level. A 12V link handles remote power on/off and an IR input on the rear panel accepts an external IR receiver.

Modular Expansion

The Helios is designed as a platform rather than a fixed-function component. Two blanking panels on the rear of the preamplifier chassis accommodate optional Gryphon modules, installable at purchase or at any future date by an authorized dealer.

PS3 MM/MC Phono Stage Module

The PS3 is a true dual-mono, fully balanced Class A phono stage with zero global negative feedback, derived from Gryphon's Legato Legacy phono design. It supports both moving magnet and moving coil cartridges, with gain switchable via the Helios menu: 64dB for MC and 42dB for MM. MC load impedance is adjustable from 20 ohms to 1,600 ohms via rear panel switches, and MM loading is fixed at 47kΩ with 220pF capacitance. The PS3 handles signals from the inherently balanced XLR output of compatible tonearm cables through the full circuit without mode conversion.

DAC3 Digital Module

The DAC3 adds five high-resolution digital inputs to the Helios: USB, AES/EBU (XLR), two S/PDIF (BNC), and TOSLINK. It is built around the ESS ES9039PRO DAC chip with discrete Class A analog output circuitry and zero global negative feedback. USB accepts PCM up to 384kHz/32-bit and DSD up to DSD512. AES/EBU and S/PDIF handle PCM up to 192kHz/32-bit. Seven user-selectable PCM digital roll-off filters allow fine-tuning of the digital presentation to taste. A 12.5 Farad super-capacitor bank powers the USB input module, acting as a true battery-like supply isolated from the AC mains.

PSU 5 Dedicated Power Supply

The PSU 5 is a matching dual-mono power supply chassis that houses the AC mains connection, main power switch, and the transformer and regulation stages that feed the Helios preamplifier via dedicated DC cables. Beyond powering the Helios, the PSU 5 provides a second set of DC outputs that can power external Gryphon source components such as the Legato Legacy phono preamplifier, reducing the number of AC power supplies in the system. Both the Helios and PSU 5 share identical external dimensions, allowing them to be stacked cleanly using Gryphon's included coasters.

Design and Build

The Helios introduces a new visual design language for Gryphon, the first product not to carry an exterior chassis design by founder Flemming Rasmussen, whose Nordic Noir aesthetic defined the brand for forty years. The waterfall-inspired faceplate honors Gryphon's aesthetic heritage while signaling a new direction. The iconic inverted triangle that appears on the Apex, Commander, and Diablo 333 is retained, but only fully visible when the preamplifier chassis is stacked atop the PSU 5, a deliberate design flourish. The chassis are CNC-machined from extruded aluminum, hard-anodized, and rest on four proprietary Gryphon-designed spikes engineered for optimal resonance control. A 4.3-inch TFT capacitive touchscreen is set behind a 4mm tempered glass panel at the center of each faceplate, with display modes optimized for both close operation and listening position readability.

The Gryphon Helios received recognition from The Absolute Sound upon its introduction, and represents Gryphon's most fully featured and flexible preamplifier design below the Commander, with the ability to serve as the long-term heart of an evolving high-end system.