Noob Question on Driver Stages

[Toyman_PA]

After reading this I was wondering...if you have a linestage preamp. Do you still need the driver stage for your power amp?

Thanks,
Toyman

[SY]

Like everything else in audio, the answer is, "It depends."

1. What's the voltage gain needed to step up from your input sources and what your speakers need?

2. Does your output stage require a balanced or single ended input? This EL84 o/p stage just needs single ended, but that's not true of most other p-p output stages.

[Sch3mat1c]

99% yes. Only the most sensitve output tubes (60FX5, 6CL6, 12BY7 (as if), etc.) have low enough drive requirements that they can be ran from a preamp output. Any other case (6L6 for instance requires up to 50V drive, plus addition gain for NFB) requires a driver.

Hard to drive tubes also need special drive, the transmitting triodes for instance often require grid current drive.

Tim