From electro-music.com wiki

Schematics: Paia 2700 BPF And LPF

DIY | Filter | VCF | Paia | LPF | BPF

Paia 2700 BPF and LPF ,for more on Paia designs ,full documentation and troubleshooting visit Paia Talk on Paia's website http://www.paia.com/talk/