On power, yes — all of them. Every one of the 13 Bluetooth receivers in this database reaches 100 dB SPL on the 64 Audio U12t, which needs 0.16 mW at its 12.6Ω.
Power is one of three questions and the one that goes wrong least often. The other two — whether the source’s output impedance leaves the frequency response alone, and whether you will hear its noise floor — are answered further down, separately, because a source can pass one and fail another.
The cheapest one that does reach it is the FiiO BTR11 at $36, which delivers 35 mW into 12.6Ω — 23 dB of headroom over the 0.16 mW this headphone needs for 100 dB SPL.
100 dB SPL is a peak level, not a listening level. If you listen at 85 dB the same headphone needs 0.01 mW, which is 15 dB less, and the answer above changes for most of the category. The model page has the full ladder.
Under the one-eighth rule the 64 Audio U12t wants a source below 1.57Ω. Of the 7 Bluetooth receivers here that publish an output impedance, 7 are under it and 0 are not.
The other 6 publish nothing at all on this, so they are not on either side of that count. This site leaves them blank rather than assuming a figure.
Hiss depends on the source’s own noise floor and on how sensitive the headphone is. At 108.0 dB/mW and 12.6Ω, the 64 Audio U12t turns one microvolt of source noise into about 7 dB SPL — and the threshold where that stops being noticeable in a quiet room is around 20 dB SPL.
Of the 6 Bluetooth receivers here that publish a noise figure, 5 stay below that threshold with this headphone and 1 cross it.
The worst of them is the FiiO BTR11, whose published 8 µV works out to 25 dB SPL of hiss in these. The hiss calculator takes your own figures.
The remaining 7 publish no noise figure, so they cannot be placed on either side.
| Source | Price | Into 12.6Ω | Output impedance | Hiss in these | Power verdict |
|---|---|---|---|---|---|
| Fosi Audio N3 | $50 | 54 mW | not published | not published | Comfortable |
| FiiO BTR13 | $59 | 94 mW | 0.6 Ω | 7 dB SPL | Comfortable |
| EarStudio ES100 MK2 | $90 | 24 mW | not published | not published | Comfortable |
| FiiO BTR15 | $109 | 130 mW | 1 Ω | 13 dB SPL | Comfortable |
| FiiO BTR5 2021 | $109 | 71 mW | 1 Ω | 13 dB SPL | Comfortable |
| HiBy W5 | $109 | 32 mW | not published | not published | Comfortable |
| Qudelix 5K | $109 | 49 mW | not published | not published | Comfortable |
| Shanling UP5 | $179 | 44 mW | not published | not published | Comfortable |
| FiiO BTR17 | $199 | 260 mW | 1 Ω | 17 dB SPL | Comfortable |
| FiiO BTR7 | $199 | 130 mW | 1.2 Ω | 17 dB SPL | Comfortable |
| Shanling UP6 | $199 | 246 mW | not published | not published | Comfortable |
| iFi GO blu | $219 | 65 mW | 1 Ω | not published | Comfortable |
Sorted by how many of the three questions the source answers well, then by price. A blank in a column is a blank in the manufacturer’s own documentation, not a zero.
The 64 Audio U12t on other categories: USB dongles · portable players · desktop amplifiers · desktop DAC/amps · audio interfaces.
The 64 Audio U12t page has every source in the database against this headphone, and the matcher takes your own numbers.