CONVERT-AD+ runs on a converter chip selected through blind listening tests by Chris Muth's team, paired with proprietary jitter-elimination technology. Beyond conversion itself, the unit offers a set of tools rarely found on an A/D converter: switchable inputs, transformers with adjustable saturation, a Clip Guard function, and zoomable digital metering.
A dual input for comparisons without recabling
Two independent, switchable stereo inputs let you swap sources with a single button — input 1 permanently wired to a mic preamp for tracking, say, input 2 fed from the mix bus after outboard processing. In practice that means instant comparison between two mastering chains, checking a mix against a reference, or switching between a tracking and a mixdown configuration without reaching behind the rack. Zoomable metering with a Peak Hold mode magnifies the top 10dB of dynamic activity, making it easier to dial in the exact level being sent to a mastering engineer.
Controlled character before conversion, not after
A pair of Hammond transformers, wired in series and switched in with one button, adds low-end density and gentle saturation to the mids and highs, while the Emphasis circuit — a parallel Baxandall-style shelf starting at 300Hz combined with gentle compression — adds up to 2dB of boost with second-harmonic content, controlled by a single blend knob. Both circuits have true hardwire bypass, so character gets added deliberately rather than as a fixed part of the signal path. Clip Guard solves a separate problem: it removes false overload information showing up on a destination device's meters without touching the signal itself, so a master can run as loud as it needs to without risking rejection by an automated quality-control system reacting to a meter reading rather than the actual sound.
KEY FEATURES
- Two independent, switchable stereo inputs
- Clip Guard removing false overload information without altering the signal
- A pair of Hammond transformers wired in series, switched in with one button
- Emphasis circuit: a parallel Baxandall-style shelf from 300Hz with compression and second-harmonic content
- Both coloring circuits with true hardwire bypass
- Zoomable digital metering with Normal and Peak Hold modes
- Digital outputs active in parallel: AES/EBU (XLR), S/PDIF, USB Audio Class 2, Wordclock Out
- Six switchable sample rates, up to 192kHz, 24-bit
- Selectable calibration level with three settings for compatibility with other gear
- Wordclock in/thru with switchable 75 Ohm termination, master or slave operation
- Proprietary jitter-elimination technology
TECHNICAL SPECIFICATIONS
- Signal-to-noise ratio (A-weighted): better than 121dB
- Signal-to-noise ratio (unweighted): better than 118dB
- Dynamic range (A-weighted): better than 121dB, (unweighted): better than 118dB
- THD+N at 1kHz, +4dBu: below 0.0011%
- THD+N at 1kHz, +22dBu: below 0.00035%
- IMD (SMPTE) 60Hz/7kHz at +4dBu: below 0.0012%
- Frequency response @ 96kHz: 20Hz-20kHz +0/-0.035dB
- Jitter: 16ps (100Hz-40kHz), 18ps (100Hz-1MHz)
- Crosstalk rejection: greater than 118dB across 15Hz-40kHz
- Maximum input level: greater than +24dBu
- Power: 3-pin IEC, auto-switching 120V/240V
