Placement of electronics

I've always placed equipment on side wall about mid way along room length. (Atma MP-1, MA-1, Modified Lenco TT, Wyred 4 sound Dac 2, Maggie 1.7, strategic placement of reflectors, bass tubes, cables are top Analysis Plus and Nordost.). The sound, sound staging etc is what I've always wanted. However, I want to upgrade the interconnects between the pre- and the amps, which are 1 foot behind the speakers. Now, the length of these cables is 20 feet. The interconnects I want to use are far too expensive to run 20 feet.

Finally, the question: If I put all the equipment between the speakers, including the TT, won't I pick up more vibration issues?
You will...what sound effect it'll have is a question. The better interconnects may make you still better off...

I have everything in the middle, but on good racks and my speakers are pulled out somewhat...
Ideal is on the side wall, well out of the killer speaker first reflection spot on either side. Also, consider an acoustic screen in front of the units. You will be surprised with the amount of acoustic energy that speakers produce and when it hits the components, it in itself produces vibrations that may impact the performance. The worst spot is between the speakers, whether they are pulled out or not. Makes nice eye candy but does nothing for the sound of your system. Turntables are a different matter, try to get it out of the room entirely, or keep it acoustically covered. When the speaker energy hits a TT all hell breaks loose. Best way to observe that problem is to get the unit out of the room and listen to the improvement.
I was shocked by the improvement of moving my rack from the middle of my speakers to the back if the room. It was like a whole different sounding system. It's a hard on to A/B that's for sure. I like it better aesthetically so that is the main thing for me but the sound definitely took on a much more tangible dimensionality after the move to a shocking degree. I think it changed other things too so much that it feels like starting over and also who knows what changing from a 1m run to a 7m run from pre to amp does to the sound. There is so much to the acoustic vibrations and damping of it with gear that its enough to make my head spin. Just don't underestimate it that's for sure.
Depends on a couple of things. No issue between the speakers if several feet behind (4 feet or more) behind the speakers and low to the floor. My gear is is only two feet off the floor and a therefore a non-issue.

Now, if your gear is on the same plane as your speakers and stand/gear 3-6 feet high, your sound will suffer.
Hmm...interesting thread. I guess I will never know what I am missing, maybe that's a good thing. My gear has ALWAYS been between my speakers, due to family and room obligations, moving equipment around is not an option. I'll just continue to suffer in this
I have had my gear between, to the near side, far side.
The best is far side. Between was OK, but never great.
I too baulk at the cost of a good quality interconnect for the gap. I use Kimber Hero 7 meters $800. lot of money for one cable. It is worth it though.
I chose the Kimber Hero because it is well reguarded. I never want to fool around with guessing which cable..
So I bought the Kimber. I am satisfied.
Where would you get such an acoustic screen?
I agree with grannyring.My components are on a low and open frame rack about 4 feet behind the speakers.The speaker as the source of sound completely disappears with most recordings.
It's pretty much a known fact these days that putting all that stuff between your speakers, right where you expect them to produce this complex sound stage, is a really bad idea.

Not even mentioning (well I guess I am) the problems with vibration on the components, especially the turntable.

Super expensive cables are so over rated it's almost criminal. And different lengths is a non-issue as well, since we are typically talking about +-10 feet max.
In a perfect world, I would use monoblocks behind or adjacent to the speakers (on the floor), using very short runs of speaker cable. Other electronics on the near side will or on the rear wall, behind your seat, connected to the monoblocks via good quality (but not necessarily expensive) XLR balanced cables. I agree with Buconero117, it would be great to get the the TT(s) out of the room but I doubt that many of us can do that. I settle for putting turntables as far away from the speakers as possible, preferably behind some other gear.
Jarraa, RPG makes a "acoustic screen" they call theirs the RPG Variscreen. I have 3 one to block off a stairway and 2 to block off dormer style windows...
I agree with putting all the equipment on the side but away from the first reflection. Vibration affecting the components is an issue but more importantly is the messing up of imaging. I would figure what you can spend on long cables and put the gear in the best spot. I sold my Kimber Heros and ran long ICs of Blue Jean LC-1s. I defy anyone to tell the audible difference between the two and the placement far outweighs the type of IC.
I have a CD-only system with 4 electronic components in a backless cabinet that is only 2 feet high and the speakers are pulled out at least 4 feet and this has worked very well, so I, too, second what Grannyring is saying.

But, if you can't get a TT into another room, you may want to approach it like a sub crawl, only in reverse in that, while playing something bass-heavy, you are listening for a room null along a given wall...avoiding a location plagued by standing waves.
jfrech's suggestion on rpg acoustic screen is okay, but furutech units can do the same thing at less then half the price. I have three furutech panels, one between the speakers to shield the tv screen, two others on the sides at first reflection points. I am working on the design of a TT acoustic screen that will come to market in 2013 as a custom designed unit keyed to the user's TT. Price point is retail of $1k.
Buconeroll can you estimate the cost of a Furtech panel? I could not find anywhere on the web. They do look attractive.
My second thread started was about this same topic. For me, using signal cable silver resolution speaker cables (I demoed many speaker cables before settling on these) sounds noticeably better to me than using belden 10awg (blue jeans) and I can't afford 20 foot runs of this cable, so my equipment is on the ground in between my speakers. My speakers are three feet from the back wall. I've found that if you have a limited budget, there are going to be comprimeses. Ideally, all of my equipment would be in a closet, all connected to its own power outlet with the shortest runs of high quality cables, but I can't do this. Also, trust your own ears. You'll get alot of responses about how a certain idea is absolutly the best way to do something and then you won't hear a difference at all. Some people can't hear a difference in cables, others can't hear a difference in regards to equipment placement (not including speakers here). For me, cables made more of a difference than equipment placement, and I do ALOT of a/b testing and critical listening. Main thing is have fun, it's not a chore, it's a hobby and lastly, trust your own ears!