Updated October 2026 · status and prices checked Oct 10, 2026.
The Short Answer
Both amps in this comparison have been replaced. The 2026 version of this matchup is Schiit Magni (Unity) vs JDS Labs Atom Amp 2, and it’s just as close as the original.
Buy the Magni (Unity) if you want the Schiit stack, a −10 dB gain setting for sensitive IEMs, or the $199 version with a DAC card built in.
The Heresy's replacement: 2.5 W into 32Ω, 415 mW into 300Ω, three gain settings. $119, or $199 with DAC.
Buy the Atom Amp 2 if you prefer JDS Labs, want an all-metal compact amp, or plan to pair it with the Atom DAC 2.
The Atom Amp+'s successor: about 2.6 W into 32Ω, roughly 2.5 times the Amp+, for about $129.
Neither, if you don’t own a DAC and want one box: the FiiO K11 R2R (~$170) does both. See today's price for the FiiO K11 R2R on Amazon ↗
Side by Side: Old and New
| Magni Heresy | Atom Amp+ | Magni (Unity) | Atom Amp 2 | |
|---|---|---|---|---|
| Status | Discontinued | Superseded | Current | Current |
| Price | $99 at launch (2019) | ~$99 (2021) | $119 / $199 with DAC | ~$129 |
| Power, 32Ω | 2.4 W (rated) | ~1 W | 2.5 W (rated) | ~2.6 W |
| Power, 300Ω | 410 mW (rated) | n/a | 415 mW (rated) | n/a |
| Gain settings | 2 | 2 | 3 (incl. −10 dB) | See JDS Labs |
| Built-in DAC option | No | No | Yes ($199) | No (separate Atom DAC 2) |
| Sold | Used only | Used / leftover | Schiit direct | JDS Labs direct |
Atom figures come from published reviews; Schiit figures are Schiit’s ratings.
Measurements: Both Families Are Clean
The Magni Heresy and Atom Amp+ were both measured by Audio Science Review and both recommended. ASR put the Heresy at a SINAD of about 119 dB in 2019. Both sit far below audibility at normal listening levels.
The successors continue that approach. Schiit lists the Magni (Unity) at about −116 dB THD+N at low gain (2 V into 300Ω). What you hear is set by the DAC and headphones, not by any of these four amps.
Sound Character
Amps this clean don’t have a sound in any meaningful sense. Owners on r/headphones and Head-Fi sometimes describe the Magni as slightly warmer and the Atom as slightly more analytical, but those reports are small and inconsistent, and they don’t show up in measurements. Choose on power, features and ecosystem.
Power: Where the Old Pair Differed
The Heresy had more than twice the Atom Amp+’s rated power into 32Ω. For 300Ω dynamics like the HD 600/650 or 250Ω Beyerdynamics, both had plenty of voltage. The gap mattered with planars, where the Heresy had more current to spare.
The Atom Amp 2 closes that gap, and now both successors sit around 2.5 W into 32Ω. Our HE400SE amp guide and Sundara amp guide explain how much a given planar actually needs, and the HD 600 amp guide covers 300Ω headphones.
Preamp Output
The Heresy had RCA preamp outputs, and the Magni (Unity) has a preamp output too. If you want one volume knob for headphones and powered speakers, the Magni is the straightforward choice. Check JDS Labs’ spec sheet for the Atom Amp 2’s preamp behaviour before buying for that use.
What DAC to Pair With
- With the Magni (Unity): the built-in DAC card ($199 total), or a Schiit Modi 5 ($149) for more inputs.
- With the Atom Amp 2: JDS Labs’ Atom DAC 2, or any clean RCA DAC.
- With either: the Topping E30 II (remote, display) or the SMSL SU-1 (smallest).
Buying: Mostly Direct
Schiit and JDS Labs sell mainly through their own websites. The buy buttons above link to Schiit and JDS Labs directly, plus an Amazon search where a listing exists.
