[old_tv_nut]

How critical a capacitor value is depends on its function, and has relatively little to do with tube vs. solid state. Power supply filter caps need to be a certain minimum size. Signal-handling cap tolerance depends on function. Stage-coupling caps need medium-tight tolerances to assure low-frequency response. Caps for functions like tuned circuits require the tightest tolerance.

Tube and transistor circuits are similar in their sensitivity to passive component values.

Tube amplifiers generally may be sensitive to individual tube parameters, while most transistor circuits are generally insensitive to transistor parameters above a certain minimum, for example if current gain (beta) >=100. There are exceptions, for example where matched transistors and/or diodes are required to maintain proper bias in push-pull power stages.