Three total. Rec, 6505 and the Windsor. On its own it’s fine. When the others are on bad ground hum. Only when the others are on. I’m using two aby’s to split everything. The rec has the ms3 in its loop for effects…. I have a bunch of pedals going to the 6505’s loop…. And I have a couple in the Windsors loop. That’s not counting what I’m slamming into the front end of each one also. It’s a very sophisticated set up…. I’m quite proud of it actually….