The Grado PS2000e is 32Ω at 99.0 dB (no figure from the maker at all); the Grado Signature S550 is 38Ω at 112.0 dB/mW. This page covers what they ask of an amplifier, not how they sound.
The PS2000e needs 13.0 dB more than the Signature S550 to reach the same loudness — 1.3 mW against 0.06 mW.
| Specification | PS2000e | Signature S550 |
|---|---|---|
| Impedance | 32 Ω | 38 Ω |
| Sensitivity | 99.0 dB | 112.0 dB/mW |
| Sensitivity (voltage) | 113.9 dB/V | 126.2 dB/V |
| Power for 100 dB | 1.3 mW | 0.06 mW |
| Voltage for 100 dB | 0.20 V | 49 mV |
| Current for 100 dB | 6.3 mA | 1.3 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 4.00 Ω | 4.75 Ω |
| Sources that reach 100 dB out of 280 | 280 | 280 |
One caution before reading the rows. For Grado PS2000e the maker publishes no sensitivity figure at all. The number in the table was collected when this database was first built and has never been traced to a manufacturer document, so treat every row below it as an estimate rather than a specification.
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 Signature S550 under the one-eighth rule but not for the PS2000e (Shanling H5).
16 sources stay below the audible-hiss threshold with the PS2000e but cross it with the Signature S550 (FiiO BTR11, FiiO K11 R2R, Lake People G103-S Mk II, 13 more).
280 of the 280 sources here reach 100 dB on both.
The PS2000e is more demanding than 59% of the 567 non-electrostatic models in this database; the Signature S550 than 10%.
| dB SPL | PS2000e power | PS2000e voltage | Signature S550 power | Signature S550 voltage |
|---|---|---|---|---|
| 80 | 0.01 mW | 20 mV | 0.6 µW | 5 mV |
| 85 | 0.04 mW | 36 mV | 2.0 µW | 9 mV |
| 90 | 0.13 mW | 63 mV | 6.3 µW | 15 mV |
| 95 | 0.40 mW | 0.11 V | 0.02 mW | 28 mV |
| 100 | 1.3 mW | 0.20 V | 0.06 mW | 49 mV |
| 105 | 4.0 mW | 0.36 V | 0.20 mW | 87 mV |
| Source | Price | Headroom, PS2000e | Headroom, Signature S550 | Output impedance | Noise |
|---|---|---|---|---|---|
| JadeAudio JA11 | $20 | 13.8 dB | 26.0 dB | 0.5 Ω | 1.7 µV |
| FiiO KA11 | $29 | 22.0 dB | 34.3 dB | 0.7 Ω | 1.7 µV |
| FiiO BTR13 | $59 | 19.0 dB | 31.2 dB | 0.6 Ω | 1.0 µV |
Of the 280 sources here, 280 reach 100 dB on both. 55 of them also publish an output impedance low enough for both under the one-eighth rule and a noise figure that stays below the audible-hiss threshold with both.
The cheapest of the 55 is the JadeAudio JA11, at $20. It leaves 13.8 dB of headroom on the PS2000e and 26.0 dB on the Signature S550, its output impedance is 0.5 Ω against a one-eighth limit of 4.00 Ω and 4.75 Ω, and its noise figure puts the hiss floor 21 dB and 9 dB below the 20 dB SPL this site treats as the point where a quiet room stops hiding it.
Both have a page of their own. In full: Grado PS2000e and Grado Signature S550. Each figure on this page is labelled on those pages with where it came from, including the ones Grado never published — what that maker publishes, counted.