The Questyle CMA Fifteen is a desktop DAC/amp at $2499. It delivers 1.5 W into 32Ω and 188 mW into 300Ω, which ranks it 42 of 156 for raw power among the sources in this database.
Measured at 100 dB SPL it has comfortable headroom on 394 of the 396 dynamic and planar headphones catalogued here and enough but not generous on 2.
The manufacturer publishes 1.5 W into 32Ω, 188 mW into 300Ω. Everything else in the table above is worked out from those figures, and this table says which is which.
The balanced output is rated separately: 2.0 W into 32Ω through the 4.4mm + 4-pin XLR jack.
Derivation holds output voltage steady between and beyond the published loads rather than output power, because that is what an amplifier actually does. The full method is written up here.
Source: questyleshop.com.
| Load | Power | Status | How it was arrived at |
|---|---|---|---|
| 32 Ω | 1.5 W | Published | the manufacturer publishes this figure at this exact load |
| 150 Ω | 344 mW | Derived | worked out between two published loads, holding output voltage linear between them |
| 300 Ω | 188 mW | Published | the manufacturer publishes this figure at this exact load |
| 600 Ω | 94 mW | Derived | beyond the published loads, holding output voltage constant — which understates rather than flatters |
Ordered from easiest to hardest to drive. Headroom is measured at 100 dB SPL, which is louder than almost anyone listens — a small negative number means the source still plays loud, just without reserve for peaks.
These figures come from each manufacturer's own sensitivity rating. A handful of planars — the HiFiMAN Susvara and HE-6se and the Abyss AB-1266 in particular — are widely reported to need far more than their published sensitivity implies, so treat a bare pass on those as optimistic rather than settled.
| Headphone | Impedance | dB/mW | Needs | Headroom | Verdict |
|---|---|---|---|---|---|
| Shure SE846 | 9 Ω | 114.0 | 0.04 mW | +40 dB | Comfortable |
| 64 Audio U12t | 13 Ω | 108.0 | 0.16 mW | +36 dB | Comfortable |
| Shure SE215 | 17 Ω | 107.0 | 0.20 mW | +36 dB | Comfortable |
| Moondrop Aria | 32 Ω | 107.1 | 0.19 mW | +39 dB | Comfortable |
| Audeze LCD-X 2021 | 20 Ω | 103.0 | 0.50 mW | +33 dB | Comfortable |
| Truthear Hexa | 21 Ω | 103.1 | 0.49 mW | +33 dB | Comfortable |
| Sennheiser HD 25 (1-II) | 70 Ω | 108.0 | 0.16 mW | +36 dB | Comfortable |
| Sennheiser IE 200 | 18 Ω | 101.6 | 0.69 mW | +31 dB | Comfortable |
| Sony MDR-7506 | 63 Ω | 106.0 | 0.25 mW | +35 dB | Comfortable |
| Meze 99 Classics | 32 Ω | 103.0 | 0.50 mW | +35 dB | Comfortable |
| Focal Clear MG | 55 Ω | 104.0 | 0.40 mW | +33 dB | Comfortable |
| Philips SHP9500 | 32 Ω | 101.0 | 0.79 mW | +33 dB | Comfortable |
| Focal Utopia | 80 Ω | 104.0 | 0.40 mW | +32 dB | Comfortable |
| Meze Empyrean | 32 Ω | 100.0 | 1.0 mW | +32 dB | Comfortable |
| Campfire Audio Andromeda 2020 | 9 Ω | 94.0 | 4.0 mW | +20 dB | Comfortable |
| Etymotic ER2SE | 15 Ω | 96.0 | 2.5 mW | +24 dB | Comfortable |
| AKG K371 | 32 Ω | 99.1 | 1.2 mW | +31 dB | Comfortable |
| Audio-Technica ATH-M50X | 38 Ω | 99.0 | 1.3 mW | +30 dB | Comfortable |
| Beyerdynamic DT 900 Pro X | 48 Ω | 100.0 | 1.0 mW | +30 dB | Comfortable |
| Audeze LCD-2 Classic | 70 Ω | 101.0 | 0.79 mW | +29 dB | Comfortable |
| Grado SR80x | 38 Ω | 98.0 | 1.6 mW | +29 dB | Comfortable |
| Sennheiser HD 560S | 120 Ω | 100.8 | 0.83 mW | +27 dB | Comfortable |
| HiFiMAN Edition XS | 18 Ω | 92.0 | 6.3 mW | +21 dB | Comfortable |
| HiFiMAN Arya Stealth | 32 Ω | 94.0 | 4.0 mW | +26 dB | Comfortable |
| Dan Clark Audio AEON 2 Closed | 13 Ω | 90.0 | 10 mW | +18 dB | Comfortable |
| Audeze LCD-5 | 14 Ω | 90.0 | 10 mW | +18 dB | Comfortable |
| HiFiMAN Sundara | 37 Ω | 94.0 | 4.0 mW | +25 dB | Comfortable |
| Beyerdynamic DT 1990 Pro (250Ω) | 250 Ω | 102.0 | 0.63 mW | +25 dB | Comfortable |
| HiFiMAN HE400se | 25 Ω | 91.0 | 7.9 mW | +22 dB | Comfortable |
| Dan Clark Audio Stealth | 23 Ω | 90.0 | 10 mW | +20 dB | Comfortable |
| Fostex T50RP MK3 | 50 Ω | 92.0 | 6.3 mW | +22 dB | Comfortable |
| AKG K702 | 62 Ω | 92.9 | 5.1 mW | +22 dB | Comfortable |
| ZMF Verite Closed | 300 Ω | 99.0 | 1.3 mW | +22 dB | Comfortable |
| Sennheiser HD 650 | 300 Ω | 97.8 | 1.7 mW | +21 dB | Comfortable |
| Sennheiser HD 800S | 300 Ω | 96.8 | 2.1 mW | +20 dB | Comfortable |
| Beyerdynamic DT 770 Pro (250Ω) | 250 Ω | 96.0 | 2.5 mW | +19 dB | Comfortable |
| Audio-Technica ATH-R70X | 470 Ω | 98.0 | 1.6 mW | +19 dB | Comfortable |
| ZMF Atrium | 300 Ω | 96.0 | 2.5 mW | +19 dB | Comfortable |
| Abyss AB-1266 Phi TC | 50 Ω | 88.0 | 16 mW | +18 dB | Comfortable |
| Sennheiser HD 600 | 300 Ω | 91.8 | 6.6 mW | +15 dB | Comfortable |
| HiFiMAN Susvara | 60 Ω | 83.0 | 50 mW | +12 dB | Comfortable |
The manufacturer does not publish an output noise figure for this source, so the hiss estimate that runs on every other page here cannot be run on this one. Rather than substitute a plausible number, this page leaves the question open.
If you know the noise figure from a measurement you trust, the hiss calculator takes it directly and tells you where that noise lands in your own in-ears.
The manufacturer does not publish an output impedance for this source. That is the one number that decides whether it leaves your headphones alone or acts as a tone control, so its absence matters more than it looks: without it, nothing here can tell you how this source will behave with a multi-driver in-ear.
If you find a measured figure you trust, the checker will work out the consequence for any headphone.
$2399 · 1.2 W into 32Ω · 0.11 Ω out
Compare →$2999 · 1.2 W into 32Ω · 11 Ω out
Compare →$1600 · 2.2 W into 32Ω · 0.25 Ω out
Compare →$1499 · 1.2 W into 32Ω · 11 Ω out
Compare →$799 · 2.0 W into 32Ω · 1.0 Ω out
Compare →$549 · 3.2 W into 32Ω · 1 Ω out
Compare →Or put any two side by side in the source comparison tool, or run your own headphones through the amplifier matcher.