Hi all,
I have built up my first 2 way L-R filter based on the schematic on Rod Elliot's website, project 81, with component's selected to give a crossover point of around 300Hz.
12dB / Octave Linkwitz Riley Crossover
It has a few issues with phase and distortion.
The first issue is that is distortion rises as the frequency rises, please see the photos below.
At ~70 Hz the waveforms are clean though out of phase by something like 3ms.
At ~1kHz the output from the high pass section start to show distortion, looking a little like crossover distortion but offset to the negative rail slightly.
At ~20Khz the output from the high pass section looks terrible and the low pass section shows weird spike things in the waveform.
The Op amps I used were TL071s, resistors were hand matched 1% metal film and the capacitors hand matched polyester film types.
What gives, is it the breadboard or have I missed something?
I have built up my first 2 way L-R filter based on the schematic on Rod Elliot's website, project 81, with component's selected to give a crossover point of around 300Hz.
12dB / Octave Linkwitz Riley Crossover
It has a few issues with phase and distortion.
The first issue is that is distortion rises as the frequency rises, please see the photos below.
At ~70 Hz the waveforms are clean though out of phase by something like 3ms.
At ~1kHz the output from the high pass section start to show distortion, looking a little like crossover distortion but offset to the negative rail slightly.
At ~20Khz the output from the high pass section looks terrible and the low pass section shows weird spike things in the waveform.
The Op amps I used were TL071s, resistors were hand matched 1% metal film and the capacitors hand matched polyester film types.
What gives, is it the breadboard or have I missed something?