47 Labs has been one of the more exotic brands in hifidom. The Model 4706 is both a power amp that you could drive with a separate preamp or use it as a one input integrated amp (they like to call it a power amp with attenuated volume control). The unit you see here is the more powerful version with two 4700-50 Power Humpty which will put out 50W per channel instead of 25W with the regular single 4700 power supply. But like its smaller brother, the 50W you hear from this little powerhouse may be the purest 50W you have ever heard (or at least we did). Barely 6.5″ wide, 4″ deep and 2″ tall, the 4706 has laid claims to several World’s first like (lifted off their website);
- World’s smallest number of parts – 9 parts per channel( excluding attenuators )
- World’s shortest signal pass length – 32 m/m ( including the length of parts )
- World’s shortest NFB loop length – 9 m/m ( including the length of the resistor )
- World’s smallest filter/condenser – 1000µF, (50W version – 2200µF)
- Dual mono construction with each channel in a separate chassis.
- Rigid and compact aluminum chassis construction to release vibrations smoothly.
- Separate 12-position attenuators for each channel.
When we paired with several different brands and types which have a nominal impedance of 8 ohm and a sensitivity of 89dB and higher, the 4706 didn’t sound like its struggling to provide the power necessary to drive those speakers. In fact, it sounded comfortable, confident. Bass was tight, the mids and highs were clear but even more impressive was its speed. Maybe it had to do with its super short signal path and little parts in its way, but the 4706 was like a bullet train. Signal in, signal out spontaneously. Don’t let this little block of aluminum fool you. The sonic quality from it will rival any amplification out there that cost up to $8,000. We had this side by side with the Pass Labs Aleph 5 and the Monarchy Audio SM-70 with the latter two brands being Class A amps. The results was quite predictable. The Monarchy was out of its league in this grouping. The Aleph 5 had a deeper bass presence but the 4706 had better transparency and pace. It does run hot like a Class A amp so even though it is small in statue, it operates like a mini heater. The 4706 will only accept speaker cables with spades so if your speaker cables are terminated with bananas, you would need a spade to banana adapter. To “turn on” the 4706, you just flip the two toggle switches up.
Cosmetically, the amp looks good. Minor scuff marks here and there with some minor scratches under the “belly” of the Power Humpty where the footers are placed but otherwise, they all look very presentable. They will be securely packed for safe shipping.