Hi Denon1, to be perfectly fair, I have listened to K-01 directly into an amp only on the demo system at RMAF. It is very possible that while various filters and upsamplers on the unit were properly broken in, the volume attenuator was still raw, hence my lack of appreciation for this mode of operation. If you get a K-01 without pre, by the time you have completed break-in of about 2100 hours (700 hours on each SDLY1+4X, SDLY2+4X, and DSD), the volume attenuator will also be totally broken in, and the machine largely optimized and giving you its best. If at that time you still have a concern, you can add a pre, otherwise continue with a direct connection. Guido