1113 Filter - Problems?

Hey All,

Just wondering if anyone knew the frequency range of the low pass on the 1113 filter? I’ve just build one and after loads of failed attempts the high pass works (seemingly - cut off around 600Hz when the 5k pot is fully clockwise). The low pass all the way clockwise cuts off at around 1k so I don’t get any frequencies past that.

I know Sam uses it for mainly in his bass synth from what I’ve seen, but should it be cutting off so low? Is this expected?

In terms of alterations, I’ve swapped a 4.7k pot for a 5k pot and I got rid of the 10r resistors (swapped them for wires) because I accidently set them on fire early on (think I got one of the caps wrong by a factor of 10) - everything else should be standard and it seems to actually filter stuff now.

In addition to this, the Resonance also self oscillates really easily. If I tweak the trimmer, I’m hardly getting any res at all whereas if I tweak it the other way, it oscillates? Is this normal too? Am I just not finding the sweet spot?

I’m not sure if its supposed to be this way or if I’ve messed something up. This is my first time building DIY and I feel like I’ve checked all my resistors and caps but I might be missing something.

Any advice?

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In case anyone was wondering, I found out I put the 470k and 4.7k the wrong way round… (as in I got them mixed up, not polarity)

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