PT-80 delay debugging

[Dweezil]

Just build Scot Swartz PT90 delay, using PT2399 chip, SA571N compander, etc. and when pedal is on the sound is just the same, dry clean without any delay. Original transistor in the unit was 2N5088 but instead I use 2N5457 or BC557. Any sugestions?! What could be the problem?

[oskar]

2n5088 are npn bipolar, bc557 are pnp bipolar and finaly 2n5457 are... well, not bipolar!
They aren't compatible.
If you substitute you need high-gain npn bipolar transistors. But check the store (link abovehttp://diystompboxes.com/zencart/index.php?main_page=product_info&cPath=2&products_id=5) and get a t-shirt too!