I play an Ibanez through a Line 6 Spider III (which I will be replacing soon as I don't like it, prob. gonna get a peavey). I started using a Boss Metalzone pedal to get more control over my distorted sound, as the Spider's insane channel sucks IMO. Using the pedal on the clean channel, I get nasty, constant feedback even with the volume knob on my guitar all the way down. I know it isn't the guitar, as I can play it on the amp's distorted channels without the feedback. Also, I brought the pedal to guitar center where one of the employees ran it through a different amp with all the knobs on the pedal all the way up, and he didn't get any feedback there. What gives? Thanks in advance
First off.....Welcome to UG

The nicest way I can put this is that a Dirt pedal in front of a Modeling amp like this is a recipe for disaster. Specifically - a Boss MetalZone in front of a Spider amp. I know you don't want to hear this but sell both and start over.

I have a Peavey Vypyr 60 (power tubes) that I got at Guitar Center for $315. The other day, I did a demo clip of some various FX pedals running into it (in profile) and that included a MXR Zach Wylde OD pedal and it actually worked really well.

anyway....free bump for ya
Thanks, kinda figured that might be part of it and tbh ive grown increasingly frustrated w the spider. It was a good starter amp but in refining my sound im gonna upgrade when i can afford to.

Glad to be here. Cheers n happy new year to you