on board pre question

[dadodetres]

hi!

my bartolini pre amo has an internat trim pot for adjustin gain.

i have it set to min, so the passive volume is the same as the active.... but when set all flat the sound doesnt change when the pre amp is enganged.

dont the pre colors the sound?
or the problem is that the trim pot is at min? so im not sending enough signal to work with?

 

[robb.]

it sounds like it's working perfectly well. i would not be surprised if bartolini designed it to be as flat and uncolored as possible -- obviously, apart from when the EQ is adjusted from flat. that means that if you're not using your EQ, it sounds the same as having no preamp at all. except that now you have a low output impedance that driving long cables isn't an issue any longer, and you won't have the loading effects driving a low input impedance mixing board like you would with a passive instrument.

from what you've described, you won't be able to get "color" out of this preamp unless by "color" you mean "distortion". you could, theoretically, eventually overdrive the preamp output by turning the gain up too much, causing distortion. but apart from that, the only reason it would sound better with more gain is best described by the fletcher-munson curves.

robb.

 

[luknfur]

hi!...dont the pre colors the sound?
or the problem is that the trim pot is at min? so im not sending enough signal to work with?

FWIW:

In my experience the EMG, Bart, and Aguilar preamps primary affect is boost/cut. The curves have some differences and they have some different options among them but variation in color in terms of preset toneshaping is minimal. I personally couldn't hear any curve going on with variation in tone control - just more or less ot the same thing. That's excluding the variables mids (which I found undesireable cause it's difficult to find a tone with one and practically impossible to get back to it when changed). They do have some inherent differeces in coloration but none was significant to me and I wouldn't choose one over another based on that. I have 2 and 3 band versions of those preamps and I ran some of them as outboards and could do side by sides with the same bass/rig. See Dimento's "Onboard" preamp experiment in the FAQ section.

Not suprising, they're basically designed to go in any bass regardless of acoustic properties, pickups, etc. and to appeal to a broad spectrum of buyers. So it's not like signature bass preamps that were taylored to cop some players tone.

Seems most of them are desinged to be flat when they're set flat so that's no surprise. It's not a trim pot issue. Otherwise you wouldn't notice a difference when controls were adjusted away from flat cause it wouldn't boost/cut either.