Yamaha A-S501chat_bubble_outlineFrom real comments

Sound quality is consistently called clean, balanced, and natural. Many long-term owners describe the A-S501 as smooth, detailed, and free of harshness, with bass that lets you hear individual notes and a tonal balance many prefer over Marantz, NAD, Rotel, and Cambridge Audio alternatives. Several call it the best amp they've owned for the money, sitting comfortably below far pricier gear like Rega or Naim while still holding its own sonically.

The Loudness control is a distinctive but divisive feature. Yamaha's Loudness dial rolls off mids/highs rather than boosting bass, letting listeners keep full bass current at lower volumes; several owners explain and praise this design once understood. Others find the manual confusing, dislike the resulting v-curve, or simply prefer leaving Pure Direct engaged instead, especially at higher listening levels.

Build quality is rugged, but cosmetic details draw criticism. Multiple commenters emphasize the tank-like weight and construction, reliability over years of use, and near-total absence of heat even when driving 4-ohm speakers hard. However, plastic knobs and square dials feel cheap in use, the built-in DAC is considered only average, and the volume potentiometer is hard to fine-tune at low levels.