Current Drive vs Voltage Drive
Animated measurement comparisons across multiple drivers. Watch the distortion disappear.
Every conventional amplifier uses voltage drive — it forces a voltage across the speaker and lets the current vary. This means distortion from the speaker's non-linear impedance feeds directly into the sound.
Current drive does the opposite — it controls the current through the voice coil directly. The result? Dramatically lower distortion, measured across every driver I have tested above low frequencies. The GIFs below alternate between voltage and current drive measurements on the same driver, same conditions. See for yourself.
BG20 Full-Range Driver
B&G Neo 8 planar — a demanding full-range transducer
94 dB SPL
Voltage vs current drive at moderate listening level. Watch the harmonic distortion peaks shrink dramatically under current drive.
104 dB SPL
Same driver pushed hard — 104dB. Even at high SPL, current drive maintains dramatically lower distortion.
2 kHz Tone
Single tone at 2kHz — the most sensitive frequency range for human hearing. Current drive cleans up the harmonics.
Three-Tone IMD Test
Three simultaneous tones reveal intermodulation distortion. Current drive virtually eliminates the IMD products.
Peerless HDS 830884
High-quality midrange — popular in high-end DIY builds
Single Tone Comparison
Clean single-tone measurement showing voltage vs current drive distortion profile.
94 dB — 200 & 333 Hz
Two-tone test at 94dB. The intermodulation products under current drive are significantly reduced.
Three-Tone IMD
Three simultaneous frequencies — the ultimate distortion stress test. Current drive wins decisively.
Three-Tone IMD (Variant)
Different frequency combination, same result — current drive consistently outperforms voltage drive.
Two-Tone IMD
Two-tone intermodulation test revealing the distortion products that color your music under voltage drive.
SEAS FA22RCZ
Premium SEAS full-range driver
Single Tone Comparison
Even on a premium SEAS driver, voltage drive produces measurably more distortion. Current drive tames it.
Two-Tone IMD
Intermodulation distortion comparison. The forest of spurious tones under voltage drive disappears with current drive.
Three-Tone IMD
Yet another three tone measurement.
The Verdict
Across 3 different drivers, 12 different test conditions, and SPL levels from 94 to 104 dB — current drive consistently reduces total harmonic distortion by 10 dB or more. This isn't theory. This is measured.
The Baffless Mixed-Mode Current Drive Amplifier gives you 3 switchable modes — voltage, and two mixed modes — starting at €250.