AKG K371 vs Grado SR80x: which needs more amplifier?

The AKG K371 is 32Ω at 99.1 dB/mW; the Grado SR80x is 38Ω at 98.0 dB/mW. This page is only about what they ask of an amplifier — not how they sound, which no specification on either sheet can tell you.

The Grado SR80x needs 1.1 dB more than the AKG K371 to reach the same loudness — 1.6 mW against 1.2 mW.

The numbers that decide it

SpecificationAKG K371Grado SR80x
Impedance32 Ω38 Ω
Sensitivity99.1 dB/mW98.0 dB/mW
Sensitivity (voltage)114.0 dB/V112.2 dB/V
Power for 100 dB1.2 mW1.6 mW
Voltage for 100 dB0.20 V0.25 V
Current for 100 dB6.2 mA6.5 mA
Highest source impedance
that leaves them alone (one-eighth rule)
4.00 Ω4.75 Ω
Sources that reach 100 dB
out of 280
280280

Where the two part company

Every source in the database that drives one of them drives the other. On power, the choice between these two changes nothing about what amplifier you need.

1 source is low enough in output impedance for the Grado SR80x under the one-eighth rule but not for the AKG K371 (Shanling H5).

280 of the 280 sources here reach 100 dB on both. That count is about power only — the output-impedance and hiss lines above are separate questions, and a source can pass this one and fail those.

Both pages in full

Each model has a page of its own with the full source list, the hiss estimate and the provenance of every figure above: AKG K371 and Grado SR80x. Every figure on this page comes from what AKG and Grado published, or is derived from it — what AKG publishes and what Grado publishes, both counted.