Steiner Parker Filter - BOM and schematic don´t match

El Mop · Joined: Aug 20, 2012 Posts: 56 Location: Germany

Hi,
I recently found a mismatch between the BOM and the schematics of the Steiner Parker Filter.
The BOM gives me a value of 8.2k for R18.
The schematic shows a value of 3.9k for R18.
Which one is the right?
Thank you.

gdavis · Posted: Tue Jun 30, 2015 10:51 am Post subject:

As it says in the schematic, you can vary the value of R18 to adjust the resonance range. So neither one is "right", it's a matter of preference. There's another thread about this a little ways down, apparently he ended up with 30k. http://electro-music.com/forum/topic-63631.html

El Mop · Joined: Aug 20, 2012 Posts: 56 Location: Germany

Thanks for the reply at first.
I know what the schematic says, but since it should be the same circuit as used in the Minibrute, I thought their must be a definte value for this.

gdavis · Posted: Tue Jun 30, 2015 9:26 pm Post subject:

Oh, you want to match the MiniBrute, why didn't you say so Wink

You can find the actual MiniBrute schematics here: http://hackabrute.yusynth.net/index_en.php?&arg=1

But even the MiniBrute has some "adjustable" resistors. For the VCF resonance, R18 in the Yusynth circuit seems to have been replaced by a 50k trimmer. Maybe Yves can provide some insight to how it's adjusted on the MiniBrute?