SIGNATURE ENGINEERING
Active DSD Bridging is a proprietary algorithm that calculates the boundary samples between seek points in a DSD stream — making the transition mathematically continuous. No fallback to PCM. No silence. No format switch. Pure DSD, throughout.
This page explains the engineering. For mathematical detail, see our white paper.
THE PROBLEM
DSD is a one-bit stream sampled at extremely high frequencies — 2.8 MHz for DSD64, up to 22.5 MHz for DSD512. Unlike PCM, where each sample carries amplitude information directly, DSD encodes amplitude through the density of ones and zeros over time. The signal at any moment depends on the samples around it.
When you seek to a different position in a DSD track, you arrive in the middle of this density pattern. The samples immediately before your seek point are gone. The samples after expect a continuous signal context. Without that context, the DAC sees a discontinuity — and discontinuities in a one-bit stream produce audible artifacts.
These artifacts are not subtle. They manifest as clicks, pops, brief silences, or — worst — a forced switch back to PCM, which defeats the purpose of DSD playback entirely.
EXISTING APPROACHES
Three approaches are commonly used for handling seeks in DSD streams. Each is a compromise. Each is audibly imperfect.
APPROACH 1
The streamer inserts a brief moment of silence at the seek point — typically 10-50 milliseconds — to mask the discontinuity. The transition is no longer abrupt, but the music has a perceptible gap. Listeners hear the seek as a pause, not a jump.
APPROACH 2
The streamer briefly converts a window around the seek point to PCM, applies a crossfade, then attempts to resume DSD. The transition is smoother, but the conversion introduces filter artifacts and breaks the bit-perfect promise. A DSD purist hears the difference.
APPROACH 3
The streamer encapsulates DSD inside PCM frames using DoP (DSD over PCM). When seeking, the entire stream switches mode briefly. The DAC must handle the format change — and many introduce a soft click as they re-lock to the new format. The stream is no longer truly native DSD.
OUR APPROACH
Active DSD Bridging takes a different path. Instead of avoiding the discontinuity (silence), masking it (crossfade), or sidestepping the format (DoP), we calculate the samples that would create a mathematically continuous transition between the two DSD regions.
When a seek occurs, the algorithm reads a small window of samples ending at the pre-seek position and another window starting at the post-seek position. Between them lies the bridge — typically 64 to 256 samples at DSD512. The algorithm computes these bridge samples to satisfy two constraints: signal continuity at both edges, and minimum spectral disturbance through the transition.
The output is a bridge that exists in the same one-bit DSD format as the surrounding stream. The DAC sees a continuous DSD signal, not a discontinuity. No format switch occurs. No conversion is required. The stream remains pure DSD, throughout.
Where mathematics permits a perfectly continuous bridge, you hear nothing. Where it does not — at impossible discontinuities — you hear the smallest possible artifact, by design.
The diagram below shows three signal regions: the pre-seek context, the calculated bridge, and the post-seek continuation. Notice that the bridge is not a fade or a substitution — it is computed signal in the same format and density as its surroundings.
COMPARISON
| Method | Silence Padding | Crossfade | DoP Fallback | Active DSD Bridging |
|---|---|---|---|---|
| Audible artifact | Brief gap | Filter artifacts | Format-switch click | None (where mathematically possible) |
| Format preserved | Yes | No (briefly PCM) | No (DSD over PCM) | Yes (pure DSD throughout) |
| DAC compatibility | Universal | Universal | DoP-capable DACs only | All native DSD DACs |
| Computational cost | Negligible | Low | Low | Moderate (real-time) |
| Bit-perfect | Yes (with gap) | No (PCM filter) | Yes (with format switch) | Yes (continuous) |
Each approach is a different trade-off. Active Bridging is ours.
VERIFIABILITY
Active DSD Bridging is verifiable through standard audio testing. Capture a DSD stream during a seek event using a USB-audio analyzer or a DAC with digital monitoring output. Compare the captured bit stream to the source file at the seek boundaries. The bridge samples will be present, in native DSD, at the expected positions.
We have published the test methodology in our white paper. The procedure does not require our hardware — any DSD-capable streamer can be tested the same way. We invite skepticism. Bit-perfect engineering is verifiable engineering.
WHERE IT LIVES
TODAY
Active DSD Bridging is currently implemented in our DMP NEXUS Player — our open-source-based playback application optimized for local DSD file playback. When you seek within a DSD track in DMP NEXUS Player, you experience continuous native DSD streaming with no format switch and no audible artifact, where mathematically possible.
Available today with every DMP ONE. Free download.
TOMORROW
Our roadmap includes integrating Active DSD Bridging into the DMP NEXUS driver itself — at the operating-system level. This will extend the algorithm beyond our player to every application: Qobuz, Tidal, Roon, Audirvana, HQPlayer, and any other DSD-capable software. The seek behavior you experience in DMP NEXUS Player today will become system-wide.
In active development. Delivered as a free firmware update.
We document what exists. We document what is coming. We don't blur the difference.