Helios DAC By Weiss Engineering

The HELIOS from Weiss Engineering is a no-compromise digital-to-analog converter (DAC) designed for those who demand the same level of audio fidelity that mastering engineers rely on. If you’re looking to experience music exactly as it’s heard in top-tier studios, HELIOS is the finest product ever produced by Weiss and your ultimate choice.

Studio Quality at Home

The HELIOS embodies the high standards that Weiss Engineering’s professional clients use in elite studios worldwide. These top-tier facilities trust Weiss DACs for their unparalleled audio accuracy, and the HELIOS brings that exacting standard to the high-end hi-fi market. With the HELIOS, you’ll hear your music exactly as the professionals do.

Unmatched Connectivity

The HELIOS offers an extensive range of digital inputs and both balanced and unbalanced analog outputs, supporting all standard sampling frequencies up to 384 kHz, along with DSD x64 and x128. It also serves as a preamp, headphone amp, and streamer (UPnP/ROON), ensuring versatile connectivity and functionality.

Seamlessly integrate with your favorite streaming services through the JPLAY iOS app, allowing you to enjoy music from Qobuz, Tidal, and your local collection in one cohesive library.

Distinctive Design and Performance

While the HELIOS shares its digital audio platform with the DAC501 and DAC502, it features a unique D/A Converter and analog output section tailored for high-end hi-fi enthusiasts. Its XLR and RCA outputs can drive amplifier line inputs and headphones directly or through a dedicated headphone amplifier, with DSP processing adaptable for speaker or headphone mode.

The HELIOS is housed in a robust dual-frame design with a stainless steel internal frame and a thick aluminum outer shell, ensuring durability and premium aesthetics.

Purist Signal Path

To deliver exceptional performance, the HELIOS employs an eight-channel 32-bit D/A converter chip with four paralleled conversion channels per audio channel. All analog processing is handled by our proprietary Weiss OP2-BP operational amplifier modules—recognized as some of the finest audio op-amps available. An internal high-precision, low-jitter clock generator ensures ultra-stable clocking for the D/A converter section.

Professional-Grade Processing

The HELIOS incorporates the same groundbreaking digital audio processing algorithms used in Weiss Engineering’s professional tools. Adjust your audio with the same high-end algorithms that shaped the original recordings.

User-Friendly Features

Control your HELIOS effortlessly with the included IR remote, which lets you select inputs, adjust outputs, toggle DSP audio processing presets, and manage power. Additionally, you can configure and control the HELIOS through a web browser for detailed DSP processing and preset management.

Experience the pinnacle of audio fidelity with the HELIOS—where studio-level performance meets high-end home listening.

Digital Inputs
There are a total of five inputs:

• AES/EBU or S/PDIF via XLR, Toslink and RCA sockets.
• UPnP/DLNA via Ethernet.
• USB.
• Roon Ready.

Accepted formats: PCM 44.1kHz up to 384 kHz, DSD 64x / 128x.
Future formats can be accommodated via software updates.

Maximum input word-length: 24 Bits

Analog Outputs
Outputs

• Line / Headphone out unbalanced on RCA connector.
• Line / Headphone out balanced on XLR connector.

Output stages based on our discrete OP2-BP Operational Amplifier design are employed.

The output levels can be set in a coarse manner with eight steps to adapt for the amplifier or headphone connected.

The levels can be set independently for line and headphone outputs.

No sound degrading servo mechanisms are used.

Digital Signal Processing
The HELIOS uses a built-in digital signal processing (DSP) chip for its audio processing. These algorithms are included:

• Room Equalizer – to suppress room modes for more accurate bass reproduction.
• Creative Equalizer – a tone control with low boost/cut, high boost/cut, and mid boost/cut. Very useful to correct those recordings which do not quite sound right.
• De-Essing – the automatic removal of overly bright sibilances from human voices. The sibilance effect can be more or less pronounced depending on your speakers or room acoustics.
• Constant Volume – adjusts the audio volume (loudness) to a constant value across all tracks played. Useful for “party mode” when the volume control should stay untouched.
• Vinyl Emulation – get that special sonic character of a record player based playback chain. We also employ an emulation of the DMM-CD procedure offered by the Stockfisch label.
• Crosstalk Cancelling (XTC) – for the playback of dummy head recordings or live recordings via speakers for an incredible live sensation. Dummy head recordings usually are listened to via headphones because they only work properly if the left channel goes to the left ear only and the right channel to the right ear only. With speakers this is difficult to achive as the left channel goes to the left and the right ear. But with some clever signal processing of the speaker channels is is possible to suppress the crosstalk, i.e. the audio going from the left speaker to the right ear and vice versa. If that works properly then the recording sounds as if one would be in the space where the recording has taken place. All the reverberation and 3D representation of the sound sources is there.(For speaker based playback only.)
• Loudness Control – a listening volume dependent equalization of the audio.
• Headphone Equalizer – to adapt any headphone to the listener’s ears in terms of frequency response.
• Crossfeed – to emulate a speaker based playback impression on headphones.

Front Panel Controls

• A rotary encoder knob for changing parameters and for powering the unit on/off.
• A touch screen colour LCD display.
• An IR receiver.

Back Panel Elements

• Analog outputs on XLR and RCA connectors.
• Digital inputs on XLR, RCA, TOSLINK, USB, and Ethernet connectors.
• USB type-A connector for various applications.
• Mains connector with fuses.

Dimensions
HELIOS

• Depth: 30 cm / 11.8 inches
• Width: 45 cm / 17.7 inches
• Height: 6.6 cm / 2.6 inches
• Height with feet: 7.4 cm / 2.9 inches

IR Remote Control

• Depth: 2.1 cm / 0.83 inches
• Width: 4.5 cm / 1.78 inches
• Height: 16.6 cm / 6.53 inches

Power Supply

A powerful non-switching power supply is used. All sensitive voltages have their own regulators which are separated between left and right channels. The result is an analog output free of “digital noise” and channel crosstalk.

The power switch activates a semiconductor relay which only switches on or off at zero crossings of the mains voltage. This assures a glitch-free power switching. The two mains transformers are toroidal types.

Mains voltage selection is done automatically by measuring the mains voltage before power is applied to the rest of the electronics.

User Manuals Download