Short answer: the MOTU M4. Both are rated 3.8/5 (#7 and #5 of 17 audio interfaces), and the MOTU M4 costs $279.95 against $449.95 for the MOTU M6, and with measured performance even, the cheaper one is the better buy.
The case for the MOTU M4: Audio Science Review measured 111 dB SINAD from its ESS Sabre32 Ultra DAC, clean for nearly all listening and competitive with good budget DACs. The catch: MOTU doesn’t publish a 32 ohm headphone power figure, and Audio Science Review measured just 18 mW into 300 ohms, calling the headphone amplifier its weakest part, so demanding headphones may run out of volume.
The case for the MOTU M6: Audio Science Review measured 112 dB SINAD from its ESS Sabre32 Ultra DAC, clean for nearly all listening. The catch: MOTU doesn’t publish a 32 ohm headphone power figure, and Audio Science Review found the headphone output poor into low impedance loads and its recording converter weaker than its DAC.
Buy the MOTU M4. Both are rated the same, and it costs $170 less than the MOTU M6.
Looking for alternatives? See the complete Headphone Amps and DACs rankings.
Specifications Side By Side
| MOTU M4 | MOTU M6 | |
|---|---|---|
| Price | $279.95 | $449.95 |
| Ranked | #7 of 17 in Audio Interfaces | #5 of 17 in Audio Interfaces |
| Device Type | Audio interface | Audio interface |
| SINAD | 111 dB (measured by Audio Science Review) | 112 dB (measured by Audio Science Review) |
| Inputs | 2 XLR/TRS combo (mic/line/Hi-Z), 2 balanced 6.35 mm line, MIDI in, USB-C | 4 XLR/TRS combo (mic/line/Hi-Z), 2 balanced 6.35 mm line, USB-C, MIDI in |
| Outputs | 4 balanced 6.35 mm TRS, 4 RCA (mirrored), headphone | 4 balanced TRS line outs, 2 headphone, MIDI out |
| Headphone Outputs | 1 x 6.35 mm | 2 x 6.35 mm |
| Balanced Output | Yes (TRS monitor outs) | Yes (TRS monitor outs) |
| DAC Chip | ESS Sabre32 Ultra | ESS Sabre32 Ultra |
| Volume Control | Hardware knob | Hardware knob |
| Dimensions | 8.3” x 1.8” x 4.3” (210 x 45 x 108 mm) | 9.2” x 4.7” x 1.8” (234 x 120 x 46 mm) |
| Weight | 2 lbs (920 g) | 2.1 lbs (975 g) |
| Output Power (300 ohms) | 18 mW (measured by Audio Science Review) | - |
Related Amp and DAC Comparisons
How MOTU M6 compares with other leading options:
- Lynx Hilo 2 USB vs MOTU M6
- MOTU M6 vs MOTU UltraLite-mk5
- MOTU M2 vs MOTU M6
- MOTU M6 vs MOTU 624
- MOTU M6 vs RME Fireface UFX III
Prices on this page were last checked October 13, 2026 at 3:17 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
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The Two Amps and DACs In Full
MOTU M4: $279.95 Amazon $279.95 eBay
Pros: Audio Science Review measured 111 dB SINAD from its ESS Sabre32 Ultra DAC, clean for nearly all listening and competitive with good budget DACs. It adds two balanced line inputs to the two XLR/TRS combo inputs, has four balanced TRS outputs with mirrored RCA outputs, MIDI in and a hardware volume knob, and Audio Science Review found its recording converter better than many computer interfaces.
Cons: MOTU doesn’t publish a 32 ohm headphone power figure, and Audio Science Review measured just 18 mW into 300 ohms, calling the headphone amplifier its weakest part, so demanding headphones may run out of volume. The Topping M62 rates higher for less.
Full MOTU M4 review and specifications →
| Released | 2020 (6 years ago) |
|---|---|
| Balanced Output | Yes (TRS monitor outs) |
| DAC Chip | ESS Sabre32 Ultra |
| Device Type | Audio interface |
| Dimensions | 8.3” x 1.8” x 4.3” (210 x 45 x 108 mm) |
| Headphone Outputs | 1 x 6.35 mm |
| Inputs | 2 XLR/TRS combo (mic/line/Hi-Z), 2 balanced 6.35 mm line, MIDI in, USB-C |
| Output Power (300 ohms) | 18 mW (measured by Audio Science Review) |
| Outputs | 4 balanced 6.35 mm TRS, 4 RCA (mirrored), headphone |
| SINAD | 111 dB (measured by Audio Science Review) |
| Volume Control | Hardware knob |
| Weight | 2 lbs (920 g) |
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
MOTU M6: $449.95 Amazon $449.95 eBay
Pros: Audio Science Review measured 112 dB SINAD from its ESS Sabre32 Ultra DAC, clean for nearly all listening. It offers four XLR/TRS combo inputs for mic, line or instrument, two more balanced line inputs, four balanced TRS outputs, two headphone outputs, MIDI in and out and a hardware volume knob.
Cons: MOTU doesn’t publish a 32 ohm headphone power figure, and Audio Science Review found the headphone output poor into low impedance loads and its recording converter weaker than its DAC. The Topping E2x2 rates higher for much less if you only need two inputs.
Full MOTU M6 review and specifications →
| Released | 2022 (4 years ago) |
|---|---|
| Balanced Output | Yes (TRS monitor outs) |
| DAC Chip | ESS Sabre32 Ultra |
| Device Type | Audio interface |
| Dimensions | 9.2” x 4.7” x 1.8” (234 x 120 x 46 mm) |
| Headphone Outputs | 2 x 6.35 mm |
| Inputs | 4 XLR/TRS combo (mic/line/Hi-Z), 2 balanced 6.35 mm line, USB-C, MIDI in |
| Outputs | 4 balanced TRS line outs, 2 headphone, MIDI out |
| SINAD | 112 dB (measured by Audio Science Review) |
| Volume Control | Hardware knob |
| Weight | 2.1 lbs (975 g) |
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons