If you already have the Wave 8's, you might try upgrading to Svetlana 6BM8 tubes, which provide a marked increase in the full range of sound. It gets much sweeter in the mids and highs, and the bass also tightens up a little bit. Also, upgrading the coupling caps to Auricaps provides a significant improvement in resolution and detail, and especially in the highs. On the whole, those upgrades cost $40 for the tubes, and about $30 for the capacitors, and bring the Wave 8 to a much higher level of performance.