A valve amplifier against a solid-state one. They are not really rivals: they differ in character, in what they will drive and in what owning them involves, so start there rather than with the watts.
| Area | Better | Why |
|---|
| Power | B | NAD C 379 BluOS-D has more power - 80W against 10W into 8 ohms. That is about 9dB - a different class of amplifier rather than a bigger version of the same one, and far more than most rooms will ever ask for. |
| Built-in DAC | B | NAD C 379 BluOS-D has a DAC on board; the other needs an external one, which is another box, another power lead and another purchase. |
| Phono stage | depends | NAD C 379 BluOS-D has a built-in phono stage and Layer Audio Design Gen-300B does not. Decisive if you own a turntable, completely irrelevant if you do not - and an outboard phono stage is easy to add later either way. |
| Use with a TV | depends | Only NAD C 379 BluOS-D has HDMI, so the television can drive it directly and one remote controls the volume. If the system is for music only, this changes nothing. |
| Amplifier type | depends | Layer Audio Design Gen-300B is Tube and NAD C 379 BluOS-D is Solid State. Valve designs are usually warmer and softer at the limits and need their tubes replaced eventually; solid state is the lower-maintenance choice. This is a taste and ownership decision, not a quality one. |
| Shelf space | depends | Layer Audio Design Gen-300B takes up about 51% less shelf area (888cm² against 1810cm²), and it is 151mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | evenly matched | Priced within a few per cent of each other. |
| Watts per dollar | B | NAD C 379 BluOS-D is the cheaper watt - about $19 per watt against $150. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Layer Audio Design Gen-300B B NAD C 379 BluOS-D
depends neither is better in the abstract - it turns on your room, your system or how you will use them. Only specs published for both amplifiers are judged; anything missing on either side is left out rather than guessed.
Which should you choose?
NAD C 379 BluOS-D has the edge on paper, though not by much. The rows marked "depends" are more likely to decide this than the score is. Start with the room. In a large or open-plan room, or with speakers that are hard to drive - low sensitivity, or an impedance that dips - NAD C 379 BluOS-D has the headroom, and headroom is what stops an amplifier hardening up on peaks. At desk distance or in a small room, 10 watts is already more than most people ever use, and the extra 70 watts would be headroom you pay for and never hear. If you play records, NAD C 379 BluOS-D saves you buying a phono stage; if you do not, ignore that row entirely.
What a spec sheet cannot show: how either sounds with your speakers, how the controls feel day to day, and what the app is like to live with - which is where most all-in-one amplifiers are actually won or lost. Power figures are the manufacturers' own and are not measured to a common standard, so treat small differences as noise. If you can hear both, that will tell you more than any row above.