AB-1266 Phi TC vs Diana MR: which needs more amplifier?

The Abyss AB-1266 Phi TC is 50Ω at 88.0 dB/mW; the Abyss Diana MR is 30Ω at 93.0 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 AB-1266 Phi TC needs 5.0 dB more than the Diana MR to reach the same loudness — 16 mW against 5.0 mW.

The numbers that decide it

SpecificationAB-1266 Phi TCDiana MR
Impedance50 Ω30 Ω
Sensitivity88.0 dB/mW93.0 dB/mW
Sensitivity (voltage)101.0 dB/V108.2 dB/V
Power for 100 dB16 mW5.0 mW
Voltage for 100 dB0.89 V0.39 V
Current for 100 dB17.8 mA12.9 mA
Highest source impedance
that leaves them alone (one-eighth rule)
6.25 Ω3.75 Ω
Sources that reach 100 dB
out of 280
275280

Where the two part company

5 of the 280 sources have the power for the Diana MR but not for the AB-1266 Phi TC — Apple USB-C dongle (EU), Zoom AMS-22, Steinberg UR22C, 2 more.

1 source is low enough in output impedance for the AB-1266 Phi TC under the one-eighth rule but not for the Diana MR (Shanling H5).

275 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: Abyss AB-1266 Phi TC and Abyss Diana MR. Every figure on this page comes from what Abyss published, or is derived from it — what that maker publishes, counted.