K240 MKII vs K361: which needs more amplifier?

The AKG K240 MKII is 55Ω at 91.4 dB/mW; the AKG K361 is 32Ω at 99.1 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 K240 MKII needs 7.7 dB more than the K361 to reach the same loudness — 7.2 mW against 1.2 mW.

The numbers that decide it

SpecificationK240 MKIIK361
Impedance55 Ω32 Ω
Sensitivity91.4 dB/mW99.1 dB/mW
Sensitivity (voltage)104.0 dB/V114.0 dB/V
Power for 100 dB7.2 mW1.2 mW
Voltage for 100 dB0.63 V0.20 V
Current for 100 dB11.5 mA6.2 mA
Highest source impedance
that leaves them alone (one-eighth rule)
6.88 Ω4.00 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 K240 MKII under the one-eighth rule but not for the K361 (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 K240 MKII and AKG K361. Every figure on this page comes from what AKG published, or is derived from it — what that maker publishes, counted.