Bleedthrough

Bleedthrough is a term used across fields to describe the unwanted transmission or visibility of material from one side, layer, or channel to another. It denotes a leakage or crossovers that can degrade readability, fidelity, or performance. While the specifics vary by domain, the core idea is that something intended to stay contained ends up apparent on the opposite side or in a neighboring path.

In printing and publishing, bleedthrough refers to ink or toner showing through the reverse side of a sheet due to paper translucency or heavy ink coverage. It can affect legibility and print quality. Mitigation includes using more opaque or heavier stock, lighter ink coverage, coatings, or adjusting layouts to reduce visible show-through.

In audio and acoustics, bleedthrough describes unintended pickup of sound by other channels or sources, such as a microphone capturing nearby instruments or a track leaking into another. This cross-talk reduces isolation and clarity. Solutions include closer or more directional miking, improved room treatment, better cable shielding, and techniques like gating or careful track isolation during mixing.

In electronics, bleedthrough refers to leakage currents or unwanted coupling between circuits, lines, or components. It can occur through dielectric leakage, parasitic paths, or insufficient isolation, especially in high-impedance nodes. Mitigation strategies include proper shielding and grounding, filtering, careful PCB layout, and the use of bleeder or discharge paths for capacitors.

Bleedthrough can also appear in imaging and document handling, where marks on the reverse side show up in scans or copies. The term is sometimes used more broadly to describe any unwanted transmission of information or signal across an intended barrier.