Why is my bass treble?

I had that problem alot with a different pickup, I dont know how good the one you have is I am sure others will respond with something about the pickup type but have you tried with a pre amp at all?

I had a lot of issues where it sounded really tinny and crappy in general no matter where I placed my pickup. Ended up being an impedence mismatch between my amp and pickup, once I added a preamp it sounded way better (but still pretty shitty as it was a crappy pickup).

I actually do have one of those, I just checked what they were, I bought one off of ebay for like 10 bucks before. With a preamp it sounded a bit better, definitly needed the preamp but still sounded pretty crappy but couldnt really complain for 10 bucks.

You may want to hit up a music store and try out a Behringer BDI21, They are like 30 or 35 bucks canadian when I got mine like 2 weeks ago or so and makes a huge difference. Most music stores will return stuff like that within 30 days so if you dont notice an improvement you can just take it back.

That will match up the impedence from your pickup to your amp and gives you some controls for the sound as well.

I am using a fishman bp100 right now and even with the preamp I am having problems with tinny/treble sound, cant wait to try out an underwood that someone sent me.

Also make sure that six rounds one is really tight in the wing of the bridge, I started to get a bit better sound out of it when I put a little shim in there to make it fit a lot tighter.