MTG Designs - Inductor Testing Part2-1200w

Magnetic Core Crossover Inductor Distortion Testing

Part 2

Harmonic Distortion Sweep at 69.5v into 4 Ohms (~1208w)

Amplifier measurement for baseline distortion reference.

Behringer iNuke 3000 amplifier in bridged mode used for the sweeps at this level.

Amplifier connected directly to the 4 ohm bench test load. This was the maximum clean sweep level (no clipping) I was able to get from the amplifier.

Dayton 1.0mH 18 Gauge Air Core.

Again no distortion is generated from this inductor itself.

The low pass effect of the inductor filters out some of the harmonics from the amp as well as reducing current/power at high frequencies which is why you see distortion is lower then the baseline amplifier measurement.

Noise floor is higher due to the lower SNR at those higher frequencies (low pass effect).

Dayton Audio 1.0mH 18 gauge Laminated Steel I-Core.

I grabbed this one just to compare against the similar sized Erse I-Core for this sweep level.

Similar design results in very similar performance with very slightly more elevated distortion level. The cross section of the laminated steel bobbin is slightly smaller then those used on the Erse 18 gauge I-Core inductors.

Saturation is not occurring at this level.

Erse Audio 1.0mH 18 gauge Laminated Steel I-Core.

Saturation is not occurring at this level.

Erse Audio 1.0mH 16 gauge Laminated Steel I-Core.

Saturation is not occurring at this level.

Erse Audio 0.8mH 16 gauge Laminated Steel Super-Q Inductor.

Saturation is not occurring at this level.

Jantzen Audio 1.0mH 15 gauge P-Core Inductor - Permite (ferrous powder).

While the 3rd harmonic is elevated the higher odd order harmonics are still fairly low in level so I do not believe saturation is starting to occur yet.