Vandersteen 1C Tweaking distance to front wall

Looking for any experience and thoughts from Vandersteen owners on your setup distance to the front wall.

The back edge of my 1c's are currently about 23" distance to the front wall.
Speakers are 7.5 feet apart and i sit about 8.5 feet away.
At moderate volume  and with good recordings the sound is fabulous with good controlled full bass.

However I tend to listen a lot at low volumes late at night and listen to lots of older recordings as well. Both these factors contribute to the sound being a little lean sounding down low. I'm considering moving them back closer to the wall to tweak up the bass frequencies. 

Any thoughts or how far are yours from the wall ? thanks
Personally? I would follow the Vandy guidelines in the set-up manual. The 1C’s have a transmission line bass ‘port’, or a narrow slit at the back/bottom of the cabinet, and not sure will get the results you desire. In addition, as Vandersteen’s are designed to emminate sound from ‘around’ its speakers, I’m afraid pushing them too close to the wall will negatively effect the performance of the tweeter/driver in providing good soundstage and imaging.

Not sure what you are driving the 1C’s with, but this is where adequate power would come into play, or, the possibility of simple tone controls. You might check out the Schiit Loki. For $150 it might be the ticket.
Many thanks. I've plenty of Amp power so no worries there. Tone controls sounds like a good option.
Backing them up to increase room gain is an option but will as noted effect imaging. Trying it is free.
thanks. I might have a play with positioning as you say it is free.
Literally talking about an inch or 2 at the most.
Backing them up start at 13 to 18 inches out also try a bit wider apart with just a bit of equal toe in and then play with tilt-back. like Tomic said it is free. Measure exactly each speaker's middle to your nose confirm they are both the same at your seating position.
I was at 19 inches from front wall with my Treo Ct's. Bottom bass octave was good, but mid to upper bass range was a bit weak. I used a pair of Vandersteen 2cWq subs. What I found out was the subs were acting like band-aids for the sound as it filled in the mid to upper bass range. I tried moving the Treos closer to the front wall going from 19 inches to 8 inches and also removing the subs. The speakers sound way better now from top to bottom without the subs. Bass is much improved. I like the Treos without the subs as sound is much more coherent with addition of better lower mids. I will have to do a lot of experimenting with the subs while trying to maintain the magic of the Treos by themselves. A major task to say the least....
Just back em up ! It varies in each room start at 10 inches to the back of the speakers and then bring them out. maintain a triangle or 20 percent out of triangle with your chair.
how is the OP doing with experimentation ? send me a PM if you need more help, Johnny R is the best
Thanks for all the suggestions guys, they were very helpful.
Playing around with positions over the last while and settled (for the moment) on this setup.

16" from back cabinet of speaker to wall.
8.5ft apart (from physical center to center)
8.5ft to listening position (from center to nose)
Slight bit of toe in.

Sound great, BIG BIG soundstage and now some nice bass sounds at low volume which I was missing before.
Bass is still tight, fast and not bloated. 

Also trying out a new dac and amp with the vandys which I’m really liking.
XTZ Edge A2-300 power amp
Topping D50s Dac which also serves as pre-amp.

Ah, the joy of the now near-ancient 'Loudness' button for those low level listening sessions where bass can disappear.
A decent tone control like the one mentioned may be easier than sliding them back and forth for listening sessions and enable the other attributes to remain at their best if the 1Cs now set up ideally.   Good luck!