I'm working on a project/experiment that requires the use of steep EQ curves for a 3-band EQ/tone control.
This would be easy using op amps by increasing the "poles" by adding serial active elements. I would ideally like to achieve at least a 24db/oct slope with as few active elements (valves) as possible... Absolute fidelity can take a hit here, I've accepted that this for experiment.
Is there a practical way to do this with tubes?
I'm thinking about how passive crossovers for speakers make use of inductors to increase the slope - can inductors also be used within preamp circuits to steepen curves? I imagine this isn't commonplace since it creates an opportunity for distortion, phase issues, trying to deal with the effects of Q and overall FR when the controls are at different levels (avoiding notches), etc...
This would be easy using op amps by increasing the "poles" by adding serial active elements. I would ideally like to achieve at least a 24db/oct slope with as few active elements (valves) as possible... Absolute fidelity can take a hit here, I've accepted that this for experiment.
Is there a practical way to do this with tubes?
I'm thinking about how passive crossovers for speakers make use of inductors to increase the slope - can inductors also be used within preamp circuits to steepen curves? I imagine this isn't commonplace since it creates an opportunity for distortion, phase issues, trying to deal with the effects of Q and overall FR when the controls are at different levels (avoiding notches), etc...
You can use inductors, but they tend to have iron cores for larger values so they have a sound. And really good ones can be expensive, say, maybe with high-nickel cores.
Other than that its some of the same issues if using feedback, in terms of phase shift and possible ringing if Q is too high. To get linear-phase you would have go digital.
Other than that its some of the same issues if using feedback, in terms of phase shift and possible ringing if Q is too high. To get linear-phase you would have go digital.