The DITA Audio Dream XLS is 22Ω at 104.0 dB (no reference unit printed); the DITA Audio Perpetua is 20Ω at 108.0 dB (no reference unit printed). This page covers what they ask of an amplifier, not how they sound.
The Dream XLS needs 4.0 dB more than the Perpetua to reach the same loudness — 0.40 mW against 0.16 mW.
| Specification | Dream XLS | Perpetua |
|---|---|---|
| Impedance | 22 Ω | 20 Ω |
| Sensitivity | 104.0 dB | 108.0 dB |
| Sensitivity (voltage) | 120.6 dB/V | 125.0 dB/V |
| Power for 100 dB | 0.40 mW | 0.16 mW |
| Voltage for 100 dB | 94 mV | 56 mV |
| Current for 100 dB | 4.3 mA | 2.8 mA |
| Highest source impedance that leaves them alone (one-eighth rule) | 2.75 Ω | 2.50 Ω |
| Sources that reach 100 dB out of 280 | 280 | 280 |
One caution before reading the rows. DITA Audio Dream XLS and DITA Audio Perpetua printed a decibel figure with no reference unit, so this page reads it as per milliwatt. If it is really per volt, each of them needs far more than the table says. Why the two readings differ by so much.
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.
9 sources stay below the audible-hiss threshold with the Dream XLS but cross it with the Perpetua (FiiO BTR11, FiiO K11 R2R, Lake People G103-S Mk II, 6 more).
280 of the 280 sources here reach 100 dB on both.
The Dream XLS is more demanding than 30% of the 567 non-electrostatic models in this database; the Perpetua than 14%.
| dB SPL | Dream XLS power | Dream XLS voltage | Perpetua power | Perpetua voltage |
|---|---|---|---|---|
| 80 | 4.0 µW | 9 mV | 1.6 µW | 6 mV |
| 85 | 0.01 mW | 17 mV | 5.0 µW | 10 mV |
| 90 | 0.04 mW | 30 mV | 0.02 mW | 18 mV |
| 95 | 0.13 mW | 53 mV | 0.05 mW | 32 mV |
| 100 | 0.40 mW | 94 mV | 0.16 mW | 56 mV |
| 105 | 1.3 mW | 0.17 V | 0.50 mW | 0.10 V |
| Source | Price | Headroom, Dream XLS | Headroom, Perpetua | Output impedance | Noise |
|---|---|---|---|---|---|
| JadeAudio JA11 | $20 | 17.1 dB | 20.7 dB | 0.5 Ω | 1.7 µV |
| FiiO KA11 | $29 | 27.4 dB | 31.5 dB | 0.7 Ω | 1.7 µV |
| FiiO BTR13 | $59 | 24.3 dB | 28.4 dB | 0.6 Ω | 1.0 µV |
Of the 280 sources here, 280 reach 100 dB on both. 62 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 62 is the JadeAudio JA11, at $20. It leaves 17.1 dB of headroom on the Dream XLS and 20.7 dB on the Perpetua, its output impedance is 0.5 Ω against a one-eighth limit of 2.75 Ω and 2.50 Ω, and its noise figure puts the hiss floor 15 dB and 10 dB below the 20 dB SPL this site treats as the point where a quiet room stops hiding it.
| Model | As printed | Tolerance | Standard |
|---|---|---|---|
| Dream XLS | 10 – 25KHz | not printed | not printed |
| Perpetua | 20 – 20,000Hz | not printed | not printed |
DITA Audio prints 10 – 25KHz for the Dream XLS and 20 – 20,000Hz for the Perpetua.
Neither range has a tolerance printed beside it, so a wider range on one sheet is not deeper bass or more treble.
Not a measurement; maker by maker.
Both have a page of their own. In full: DITA Audio Dream XLS and DITA Audio Perpetua. Each figure on this page is labelled on those pages with where it came from, including the ones DITA Audio never published — what that maker publishes, counted.