Yamaha Studio Monitors

No, the HS series are active speakers and feature an amplifier built into the enclosure which is matched specifically to power the monitor's drivers.

The HS speakers feature XLR and TRS jack connections, both of which are balanced connections, using unbalanced cables with these sort of cables can result in loss of volume as well as phasing and other audio interferences, so we would definitely recommend you use balanced cables.

It depends on the audio you are mixing and the size of your studio, a large number of musicians and producers don't feel the need for a subwoofer. However, for larger studio rooms, or those making hip-hop, electro and film scores, a subwoofer will give you more control over your low end frequencies. The Yamaha HS8S Sub is designed to perfectly complement the reference monitors in the HS range.