If you're noticing changes in your SQ during the late hours when nothing else is running, you likely will benefit from some sort of mains conditioning. I know of several including bigfatpaulie who have noticed an improvement in SQ with their DAVE and a PS Audio AC regenerator. I also know of one person who felt his AC regenerator (a P10) robbed his speaker system which includes a DAVE of dynamics and didn't feel the tradeoff was worthwhile and so he moved away from it. The one area where AC regenerators may be a necessity is if you have wildly fluctuating mains voltages since an AC regenerator will tightly regulate this. It would be ideal if you could try before you buy.
romaz, thanks for this. I should be taking delivery of a loan PS Audio P3 today, so will soon learn what if any benefit it can bring to the Dave. I've not tested my mains so do not know if it has wildly swinging voltages. Yes, things do sound cleaner at night and that probably does have something to do with a cleaner more stable mains supply over the late/early hours. But I think some of it is probably also due to being able to concentrate more on the music as things are quite, lights are subdued (sometimes even turned off altogether), I'm relaxed and the other senses have largely closed down. Anyway, I'll give the P3 a good try out.
The UK distributor of HFC cables has now returned from holiday and I will speak with him about either a demo or (better still) a loan of one of the cheaper mains cables.
Thank you also for your comments on the DHC cables. Can you confirm that the Silver Complement would add extra detail, transparency and dynamism compared to the HE1000 stock cable (SE), while not taking anything away from the bass? I did look at your post mentioning those other cables but if they only get me half way between the HE1000 stock and the Complement, for the money I think I would prefer to go for the latter. Thanks again