I enjoy my BB, but I’ve noticed how it biases my tone toward the treble en–quite a bit. (So much so that I have to put the treble on my Princeton RI amp down to 1.) Since the BB doesn’t have an on/off power switch, I use the power cord as a switch: unplugging it and plugging it back in. As long as the unit is ‘on’ and operational, the treble bias exists. Unplugging the cord makes it go away. The problem I have is this: I don’t use the BB on every song I perform, so the act of unplugging it (and then needing to re-adjust the tone knob on the guitar or amp for the treble bias) is a pain in the arse. What I’m hoping some of you folks can help me with is this: a) why is this happening, and b) what can I do to solve the problem? Thanks.
Your BB pedal will sound its best when run through a full-range amplifier—which guitar amplifiers are not 
Does your Princeton have a 10” speaker? That could be a reason for the trebley sound. However, I’m thinking there could be something else at play with your setup. Some things to try:
Different patch cable between pedal and amp.
Plug the pedal into input 1 on your amp as a stand-alone and test the BB sound; if it sounds better, plug your guitar into input 2 and see how they both sound.
Try different outputs from your pedal.
If all else fails, try running the pedal through a small mixer.
Let us know what you did to get it all sorted out.
Thank you for your input, Persist. To be clear, I’m not having a problem with my BB’s tone. It’s that when the BB is plugged in, in changed my guitar tone, making it too treble-biased.
My Princeton (with 10" speaker) has two inputs. One is occupied by the guitar input, and the other has the BB plugged in. I’ll switch both around to the other input and see if that changes anything. If it does, I’ll let the forum know.
I think, but could be mistaken that the Princeton’s two inputs are different. One is louder (brighter?) than the other and your guitar volume may control the volume of whatever’s plugged into the second input.
All good thoughts on your part, Persist, and I appreciate them. I tried switching the inputs and it made no difference. I also noticed that the treble bias seems less today. I realize that makes little sense. Tubes are good in the amp.
Hey Brian,
Are you plugging the guitar directly into the Princeton or are you using an effect(s) on the pedalboard between the guitar and the amp?
I believe input 1 on the amp is intended for a low output passive guitar PU and input 2 for an instrument that may have active PU’s with hotter output or from an effects pedal. While it sort of works, using both inputs uses resistors to passively mix the two signals. The downside of resistive/passive mixing of signals is the circuits of each source can interact with each other and can cause issues. I actually would have thought using the BB into one of the inputs would have caused a loss of the treble as it may tend to load down the guitar PU’s, but you seem to be seeing the opposite. I don’t know the circuitry in the BB, but if they have an inductor on its output to block internal digital noise from getting to the output, it quite possibly may be causing an EQ effect of sorts that affects the treble of the guitar. There likely is a capacitor coupling the audio out of the BB as well.
Below is a schematic of the Princeton’s inputs. The input jacks have contacts which open when a plug is inserted which changes the signal path and the signal return ground. I did basic sketch of how it would look if both jacks had plugs in them. Both the BB and guitar are ‘mixed’ by two 68k ohms resistors with a signal return to ground through a 1 M ohm resistor. Some of the BB signal very well could be going back through the PU’s in your guitar if they are passive. A small mixer would probably be the best way to go that would have a Hi-Z input for the guitar and a line input for the BB. I don’t really see a solution to try and use two inputs on amp to mix the two signals.
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Rather than using your amp as a mixer, try routing the guitar tone though the BB (input) and plug just the BB output into your amp.
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Maybe a noob and dumb question, why put the BB in sleep mode, for the songs you don’t use it for?