An introduction to Lyra 1

An introduction to Lyra 1

The Prism Sound Lyra 1 is a USB audio interface that provides musicians, vocalists, songwriters, and audio engineers with reliable precision and high-resolution audio I/O in home, project, and mobile studios. Its reliable clock allows it to operate at resolutions of up to 24-bit / 192 kHz with minimum jitter. It's ideal for recording, overdubbing, and even send-and-return routing, with latency as low as 0.08 Ms.

The stereo 1/4" TRS inputs, 1/4" instrument input, and XLR 3-pin input can be used to connect line, instrument, or microphone sources. The input pads and built-in limiters, as well as the phantom power, are all selectable. The front-panel 1/4" jack has dedicated level and mix controls for remote headphone monitoring, while the stereo 1/4" line outputs are excellent for connecting to speakers. TOSLINK optical I/O ports also make it simple to connect S/PDIF digital equipment.

The Lyra 1's Class-Compliant USB 2.0 interface makes it compatible with both Mac OS X and Windows PCs. A USB cord and an IEC power cable are supplied.

Features:

• Prism Sound audio quality without compromise

• USB interface that is class-compliant (UAC2)

• ASIO and WDM drivers for Windows (32- bit and 64-bit)

• The Native CORE AUDIO on Mac OS X

• The UAC2 operation on Linux (no control panel support)

• Two premium-quality Prism Sound AD channels

• Two premium-quality Prism Sound DA channels, with separate stereo headphone DA

• The Low-latency "console-quality" digital mixer for foldback monitoring

• Fader, pan, cut, solo on every mixer channel

• Front-panel master volume control, assignable to selected channels

• The Built-in high-quality sample rate conversion is accessible on the digital input.

• The Prism Sound SNS noise shaping on digital outputs (4 curves)

• Fully-floating (isolated) balanced architecture for improved noise rejection

• State-of-the-art clock generation using unique hybrid 2-stage DPLL

How does it work?

Signal Path

The audio driver on the host computer makes analog and digital input channels available to your audio workstation software. The Analog and digital outputs, as well as stereo headphone outputs, can all be played separately. Each output pair can be fed by the built-in DSP mixer with an independent local mix of several inputs through the controller applet for low-latency monitoring to a headphone or main outputs. All analog inputs are electronically balanced, with unbalanced operation enabled by default. Analog outputs are electronically balanced (level is maintained if one leg is grounded).

Verified Technology

Verified is a revolutionary new proprietary technology developed by Prism Sound that allows computer audio streams and recorded files to be swiftly examined for various clicks, mistakes, and dropouts while preserving the audio content and metadata. Verified is a delicate steganographic procedure that embeds derivative data into the ADC's dither, containing a rolling hash code that allows the audio data to be examined thoroughly and continually. When this data is recovered from an audio stream or file, it can be verified that the stream or file contains the precise audio data produced by the ADC at the moment of recording. Any wrong samples, missing or repeated audio segments, or other audio defects in the generated files may all be reliably recognized, ensuring that the recorded file is error-free. The processing applied to a Verified recording, such as EQ, level alterations, extra re-dithering, or sample-rate conversion, will fail to decode the rolling hash code in the dither, indicating that the recording is not an original.

Full Prism Sound audio quality with no compromises

The audio quality of the Prism Lyra-1 is uncompromised. It's the culmination of years of digital audio conversion research and development, as well as considerable consultation with Prism Sound's consumers.

The Prism Sound quality at an even more accessible price point was the Lyra design brief. Lyra shares its sibling Orpheus's no-compromise analog front. It backs ends, and the same fully-balanced-out architecture and isolation barriers shield the analog from digital and computer influence.

Prism Sound has years of experience designing digital audio products, including its audio test equipment, used by a broad spectrum of clients in the audio business, from pro-audio to consumer electronics. Lyra is well-behaved, both a computer peripheral and an audio processor due to this experience.

Professional recording requires a high level of dependability. Prism Sound's converters have always relied heavily on accurate software calibration processes — pots and tweaks are inherently unreliable; thus, there are none.

The design team went to significant lengths to keep noise and interference, particularly hum, to a minimum. The unit electronically balanced I/O allows it to handle familiar mode interference sources and trouble-free connection to unbalanced equipment, and all analog circuits have galvanic isolation.

THD+N measurements are commonly stated not necessarily to correspond well with the perception of sound quality. This is accurate - partially because traditional THD+N or SINAD given as RMS figures are a broad measure. With this in mind, we've gone to great lengths to ensure that not only is the RMS THD+N number excellent but that the Lyra noise and distortion spectrum is faultless and that Lyra delivers the most transparent listening experience possible.

Compatibility with USB 2.0

We used a USB2 interface to produce Prisam Lyra-1, compatible with the most extensive range of computer hardware. This is a UAC2 or USB Audio Class 2 interface that is natively supported in Mac, Linux, Android, and via a driver in Windows.

Prism Sound has recognized the growing relevance of native processing power for professional users, as well as the fact that software for mainstream PC and Mac platforms has improved dramatically in recent years.

Prism Sound is well known for A/D and D/A converters like the venerable ADA-8XR and Orpheus, a FireWire interface. However, the ADA-8XR's flexibility and versatility come at a higher cost, reflecting that no other interface offers such high audio quality or can work directly with Pro Tools Core/Processing cards while still operating a DSD processor or FireWire interface.

Lyra is simple to link to your computer and outboard equipment. For Windows users, ASIO is available (with WDM on the way), while Lyra interfaces directly with Core Audio for Mac OS X 10.4 and later. A controller application for both Mac and PC platforms allows you to configure the unit and control its built-in mixing and other features. Everything else is controlled entirely through the Lyra controller program, except monitor and headphone level adjustments. The controller software appears onscreen as a distinct panel and your existing editing program. Lyra will operate in newer Linux and Android releases because it is UAC2 compatible; however, no control panel is given.

With the deployment of AVB (Audio Video Bridging), an IEEE 802.1 networking standard, low-latency synchronized networked audio and video is rapidly becoming a reality.

Flexible I/O

The Lyra features software-controlled gain in 1 dB steps, switchable phantom power, a 20 dB pad, and low noise and distortion, and uses the same mic amps as the Orpheus. With software override, the inputs are auto-sensing. The first channel can be an instrument or a line, while the second can be a microphone or a bar. Analog inputs contain individually configurable Prism Sound Overkilled peak limiters to catch those quick transients, similar to the ADA-8XR and Orpheus. The Overkill threshold automatically adjusts to the operating line level (+4 dBu or -10 dBV). Overkillers are perfect for percussive sounds, especially drums, where headroom is concerned.

Digital Mixer with Low Latency

The built-in digital mixer can be configured from the host computer to offer foldback feeds to performers, with each receiving their stereo mix of workstation playback and any of the inputs. This delivers console-quality local mixing—each output has its independent mixer, replete with fader, pan/balance pot, solo, and mute buttons, and full metering for all inputs and workstation feeds. Strips can be stereo or mono, and mixes are dithered using filtered coefficients, just like a high-end digital mixer. At a 192 kHz sampling rate, the latency of the Prism Sound DSP mixer is as low as 0.08 Ms.

Noise Shaping and Sample Rate Conversion

Any standard input sample rate between 44.1 kHz and 192 kHz can be used with sample rate conversion on the digital input. The digital output features four Prism Sound SNS noise-shaping curves, allowing you to be downscaled to 16 bits for CD mastering quality.

Stable Clocking

The State-of-the-art clock generation with proprietary hybrid 2-stage DPLL keeps jitter to a minimum. The sample rate can be determined using the local clock or the S/PDIF input stream.