Power Conditioner Advice please...


I would be grateful for advice from the forum with regard to the following:

My system sounds significantly better in the evening/night than during the day and given that I live in a busy commercial area it would seem likely that I need to clean up the power. 

Ultimately, I will buy an AC regenerator but do not currently have the budget for that. I am therefore looking at a power conditioner and which I hope to buy pre-owned for under $/£1,000.

Given my amps draw a large wattage (peak 400w into 4ohms) I am nervous about placing a conditioner between them and the mains.

The other components:

1.     Auralic Aries - has its own external linear power supply.

2.     DEQX  -  “Nine separate power-supply regulation stages  including four that provide the main analog rails deliver extremely low measured distortion....

Where do you think I would be best to apply any power conditioning?

Any other suggestions welcomed.

Thanks very much

soma70
I wasn't sure, so I just checked the PS Audio site. Their old re generators put out balanced power, but the newer P-3,5,10 do not. Paul feels that balanced power is good, but not from a transformer. Anyway, I'm not looking to butt in here, but since I have also been considering a P10 I thought it best to mention. If anyone can confirm the balanced power question that would be helpful.
the isolation trans. needs to be sized to your system's power demands to prevent it from limiting dynamics

power quality should be better at night in a large city or near a commercial district

In an R1 zone not so much

I am having my elec. utility put a measuring device on my meter head and they say they can also do RF checks - already have a few moths data from the sub-station I draw from but not too helpful at the 12 kV range...
Thanks to everyone for the additional input which is all very interesting. I just need to note here that I am based in the UK (so some of the suggested products are not available here) and I did install a dedicated 20 amp feed from the breaker box with its own ground and so I believe the internal power is pretty good. PS Audio supply in the UK and so I plan to buy a Dectet and will report back if that makes an improvement to SQ during the day...I need to sell a mini-dsp on eBay before I can purchase the Dectet but promise to report back here as soon as I am able.
Take a look at PI Audio Group: http://www.piaudiogroup.com - Dave is AMAZING to work with. He helped be select the best solution that is well suited for my setup. He *really* knows his stuff.

My UberBUSS (http://www.piaudiogroup.com/UberBUSS.html) will be in my system soon so I can't talk about performance in my system just yet. I will be sure to post an in-depth review as soon as I have put some listening hours in.

Until then... head over to the site and check it out!

-Ron
@ivan_nosnibor 
that was such a helpful post.

Can I just say that regenerators can sometimes compress dynamics when there is a large or sudden current draw. So you may get smoothness and quietness at the cost of dynamics and range. Have the amp designers ever recommended anything?