Short answer
Both are desktop amplifiers, $540 against $600.
The Little Dot MK III SE reaches 100 dB on 567 of the 567 models here, the Soncoz SGA1 on 566.
| Specification | Little Dot MK III SE | Soncoz SGA1 |
|---|---|---|
| Power into 32Ω | 2.5 W | 407 mW |
| Power into 150Ω | 1.5 W | 207 mW |
| Power into 300Ω | 800 mW | 210 mW |
| Power into 600Ω | 400 mW | 105 mW |
| Output impedance | not published | 0.1 Ω |
| Output noise | not published | 1.8 µV |
| Price | $540 | $600 |
| Headphones it reaches 100 dB on out of 567 | 567 | 566 |
Not published means the maker leaves it out, so that axis cannot be compared.
| Balanced | Little Dot MK III SE | Soncoz SGA1 |
|---|---|---|
| Socket | no separate rating | 4-Pin XLR + 4.4mm |
| Power into 32Ω | — | 407 mW derived |
| Power into 300Ω | — | 840 mW |
| Output impedance | — | 0.05 Ω |
| Output noise | — | 3.6 µV |
| Headphones it reaches 100 dB on out of 567 | — | 566 |
Only the Soncoz SGA1 has a separate balanced rating from its maker; through it, it reaches 100 dB on 566 of the 567 models here. The Little Dot MK III SE may still have a balanced socket — its spec sheet simply gives no figure for one, so there is nothing to put beside it. Derived figures are worked out from the loads the maker did publish.
| Load | Little Dot MK III SE | Soncoz SGA1 |
|---|---|---|
| 32 Ω | Published | Derived |
| 150 Ω | Derived | Derived |
| 300 Ω | Published | Published |
| 600 Ω | Derived | Published |
Both makers publish a power rating. Little Dot MK III SE publishes at 32 Ω and at 300 Ω; Soncoz SGA1 at 300 Ω and at 600 Ω. The other rows are worked out from those.
So the two columns are not equally firm row by row: at 32 Ω only the Little Dot MK III SE figure is the maker’s own and at 600 Ω only the Soncoz SGA1 figure is the maker’s own. On those rows the derived number is the one to doubt first.
1 headphone reaches 100 dB on the Little Dot MK III SE but not on the Soncoz SGA1 — Symphonium Titan.
566 of the 567 models here reach 100 dB on both.
Headroom is at a 100 dB SPL peak.
The widest gap on the list is the Audeze LCD-2 Classic: Little Dot MK III SE has +34 dB of headroom there against +25 dB. 8 dB is about 7 times the power, which matters for peaks rather than for how loud the music sits.
The hiss columns are empty for Little Dot MK III SE because that maker publishes no output noise figure.
| Headphone | Impedance | Needs | Little Dot MK III SE headroom | Soncoz SGA1 headroom | Little Dot MK III SE hiss | Soncoz SGA1 hiss |
|---|---|---|---|---|---|---|
| Shure SE846 | 9 Ω | 0.04 mW | +42 dB | +35 dB | not published | 20 dB |
| Campfire Audio Andromeda 2020 | 9 Ω | 4.0 mW | +22 dB | +15 dB | not published | -0 dB |
| Audeze LCD-2 Classic | 70 Ω | 0.79 mW | +34 dB | +25 dB | not published | -2 dB |
| Beyerdynamic DT 1990 Pro (250Ω) | 250 Ω | 0.63 mW | +32 dB | +25 dB | not published | -7 dB |
| HiFiMAN HE400se | 25 Ω | 7.9 mW | +24 dB | +16 dB | not published | -8 dB |
| Audio-Technica ATH-R70X | 470 Ω | 1.6 mW | +25 dB | +19 dB | not published | -14 dB |
| Sennheiser HD 600 | 300 Ω | 6.6 mW | +21 dB | +15 dB | not published | -18 dB |
| HiFiMAN Susvara | 60 Ω | 50 mW | +16 dB | +8 dB | not published | -20 dB |
The Soncoz SGA1 costs $60 more than the Little Dot MK III SE, and on these three axes the money buys nothing: among the 567 models here there is not one that the Soncoz SGA1 handles and the Little Dot MK III SE does not — not on power, not on the one-eighth rule, not on hiss. The traffic runs the other way: the cheaper Little Dot MK III SE drives one model to 100 dB that the Soncoz SGA1 does not.
Only published figures count here; blank axes are counted separately.
Each in full: Little Dot MK III SE and Soncoz SGA1.