bcarso
Well-known member
Any design is an exercise in tradeoffs and constraints, and mic pre design as much so as any. Some parameters are mutually almost exclusive.
Having said that, in what would a reasonable wish list consist, for a transformerless balanced design? Let's start with one where the power supply is external so at least we're not tied down to phantom power restrictions. If in the end phantom is enough, all the better.
The device can OTOH provide good clean phantom power for the particular mic---I just mean don't expect the preamp to be powered from the console.
Some of the things that come to mind: low noise, wide dynamic range with polite overload if possible, variable input loading, low distortion with special attention paid to making higher-order products negligible. Excellent common-mode rejection, excellent match of + and - outputs' impedance to common, low susceptibility to EMI/RFI and power line noise/fluctuations. Stability with time and ambient temperature. Flat or at least adjustable frequency response, like some low frequency rolloff adjustments. Good transient response. Fairly bulletproof against abuse.
Remote control of some of the adjustable parameters?
No use of unavailable parts, within reason. Obsolete but supposedly readily available NOS tubes considered but discouraged if production units will work.
Low cost ;^o !
Your inputs are respectfully solicited.
Having said that, in what would a reasonable wish list consist, for a transformerless balanced design? Let's start with one where the power supply is external so at least we're not tied down to phantom power restrictions. If in the end phantom is enough, all the better.
The device can OTOH provide good clean phantom power for the particular mic---I just mean don't expect the preamp to be powered from the console.
Some of the things that come to mind: low noise, wide dynamic range with polite overload if possible, variable input loading, low distortion with special attention paid to making higher-order products negligible. Excellent common-mode rejection, excellent match of + and - outputs' impedance to common, low susceptibility to EMI/RFI and power line noise/fluctuations. Stability with time and ambient temperature. Flat or at least adjustable frequency response, like some low frequency rolloff adjustments. Good transient response. Fairly bulletproof against abuse.
Remote control of some of the adjustable parameters?
No use of unavailable parts, within reason. Obsolete but supposedly readily available NOS tubes considered but discouraged if production units will work.
Low cost ;^o !
Your inputs are respectfully solicited.