I could use some help. I'm looking for a relatively straightforward, compact, pre-amp (balance and source selection optional) + tone control (2-3 band) solution for use with a small Class D amp on my desk. I'd like to keep it solid-state (no tubes).
I'd like it to, um, not suck, by which I guess I mean: I'd like it to have no easily discernible impact on the output when the controls are set to a neutral position, and to introduce a minimum of noise and distortion when boosting or attenuating a band. As for the controls, I'd prefer knobs (whether pots or rotary encoders) with neutral effect at their midpoint.
If the controls are digital, I'm fine with a single knob, as long as its easy to switch modes, to identify the current mode, and to see where in the range it's set. I'd rather have individual LEDs to indicate the mode, and some sort of multi-segment bar to show the setting, rather than a chunky dot-matrix LCD display. I realize that I may need to be flexible on this want.
My first choice would be an inexpensive (less than $20) finished board. Second choice is a similarly priced kit. Third choice is reference to a good IC (or two) with proven designs that I can build from.
In all cases, I'd prefer something that can run from a single supply rail, or, barring that, something that would work well with a virtual ground within the 19-24v supply used by the power amp.
On my own I've found a lot of finished boards and kits I don't want to use, thanks to their use of rather noisy old ICs (ie LM1306, TDA1524) or ICs that I can't find much hard data on, but I'm suspicious of (ie XR1075).
I've also found boards, kits and projects based on more modern chips with digital controls. Unfortunately, the ones I've found are either past the upper range of my budget and/or require more integration/programming than I want to do at this point.
One kit I have considered is this XY HiFi kit, which uses discreets and a few (upgradeable) op-amps. I'll probably buy one and try it out, but I'd appreciate any pointers that would help me learn more about it (like whether the circuit it implements has a name).
I've been looking at forum posts. They've helped me rule some things out, and pointed me towards a few things with potential, but that seem to exceed my time and materials budget for this little project.
So, now I'm hoping that some of you can help point me to things I've missed so far. That includes informing me that what I'm asking for isn't realistic (which I'm already suspecting is the case for anything with a modern IC solution with integrated controls). Thanks!
I'd like it to, um, not suck, by which I guess I mean: I'd like it to have no easily discernible impact on the output when the controls are set to a neutral position, and to introduce a minimum of noise and distortion when boosting or attenuating a band. As for the controls, I'd prefer knobs (whether pots or rotary encoders) with neutral effect at their midpoint.
If the controls are digital, I'm fine with a single knob, as long as its easy to switch modes, to identify the current mode, and to see where in the range it's set. I'd rather have individual LEDs to indicate the mode, and some sort of multi-segment bar to show the setting, rather than a chunky dot-matrix LCD display. I realize that I may need to be flexible on this want.
My first choice would be an inexpensive (less than $20) finished board. Second choice is a similarly priced kit. Third choice is reference to a good IC (or two) with proven designs that I can build from.
In all cases, I'd prefer something that can run from a single supply rail, or, barring that, something that would work well with a virtual ground within the 19-24v supply used by the power amp.
On my own I've found a lot of finished boards and kits I don't want to use, thanks to their use of rather noisy old ICs (ie LM1306, TDA1524) or ICs that I can't find much hard data on, but I'm suspicious of (ie XR1075).
I've also found boards, kits and projects based on more modern chips with digital controls. Unfortunately, the ones I've found are either past the upper range of my budget and/or require more integration/programming than I want to do at this point.
One kit I have considered is this XY HiFi kit, which uses discreets and a few (upgradeable) op-amps. I'll probably buy one and try it out, but I'd appreciate any pointers that would help me learn more about it (like whether the circuit it implements has a name).
I've been looking at forum posts. They've helped me rule some things out, and pointed me towards a few things with potential, but that seem to exceed my time and materials budget for this little project.
So, now I'm hoping that some of you can help point me to things I've missed so far. That includes informing me that what I'm asking for isn't realistic (which I'm already suspecting is the case for anything with a modern IC solution with integrated controls). Thanks!
