How long is too long for interconnects?


I'm looking at upgrading the audio in my photo studio. I have some position limitations due to the lighting gear etc. 

Would it be a bad thing if I put my source and pre-amp up on a shelf and ran interconnects to monoblock amps located at the speakers? The lengths would be about 8 feet to the closest speaker and 12 feet to the furthest; I guess it'd be best to then purchase 2 x 12 foot interconnects, right? 

Any/all thoughts/advice greatly appreciated!
benchwarmer
Since the OP has his system in his photo studio there might be more issues with noise caused by the lighting equipment. I don't know anything about photo gear but I'm guessing there will be dimmers and devices that control light flashes and what not with high current draws, which may contribute to more noise in a RCA cable. I have always followed the principle that RCA cables are fine for lengths of 10' or less and should never exceed 15'

I've never had an issue with long speaker cable runs. The longest cable run I had to make was 100'. I would bump up the gauge of the cable for lengths over 25' and I used cable that had a heavy rubber jacket.

My vote is for shorter IC's if using RCA connectors. 
Yogi is right, the distances the OP is asking about just aren't long enough either way to make much difference.  12 foot ICs are fine, balanced or un...unless he lives near a transmitting tower.  Ditto speaker wires, in almost any case that length won't cause adverse voltage drop or any other loss of signal quality.  Without any other details on the equipment in question, my advice is to do what works best for your situation and enjoy...
I recommend longer ICs and shorter speaker cables after much trial and error. The best budget ICs are Blue Jean Cables LC-1. Low capacitance, shielded and cold welded connectors. Buy equal lengths (not custom) and try them. You can return them but I still use them for stereo and HT including 15’ runs. Well built and well priced. 
Long speaker cables are worse than long xlr cables. RCA also has restrictions for maximum length. XLR is the preferred way to hook up all equipment using long lengths and/or your equipment is balanced. Also, very short speaker cables aren’t good either. I remember reading years ago that there is a minimum Length like 4’ or more and then a Recommended maximum length. 
I have a strange setup with my integrated amp in a recess behind my wall-mounted TV above the fireplace.  My equipment rack with my digital and analog sources sits in the right corner of the room connected with 5m (16.4ft) rca cables. My tower speakers sit on each side of the fireplace with approx 12 ft speaker cables. I have had zero issues with interference, noise or hum. I was particular when running my interconnects to avoid contact with any power cables which might contribute but I wouldn't be concerned with longer interconnects or speaker cables to a reasonable point.
for over a decade i had my source and preamp stack near my listening position and amp/s between my speakers. Cables ran nearly 30 feet.  They were usually  unbalanced, with a faraday shield. Nothing fancy.  Noise from those interconnects was never a problem.  I also had balanced cables (both preamp and amp were native balanced - use half or the entire signal), but rarely used them for practical reasons.
I actually think its a **good** idea if it allows you to minimize speaker cables, or place an amp where it gets good ventilation, or some other meaningful benefit. Of course, my cables never cost a gazillion dollars a foot - which with some stuff is a very real consideration.  A few fractions of an ohm and the tiny added capacitance are really of no consequence when the termination is 10-100k ohms, resistive.
Good advice above. I ideally ALL cables would be as short as possible. But then we'd all be listening to Bose Wave Radios. My suggestions:

1. For unbalanced connections, keep the lowest level connections as short as possible. These would be (in order of lowest to highest) analog source (turntable, tape) to step up, step-up to preamp, preamp to amp, amp to speakers. Thus ICs should be shortest and speaker cables longest. There are exceptions to this rule, or course.

2- For balanced connections, keep source level connections as short as possible. Preamp to amp connections can be as long as needed (within limits). Speaker cables can be short if preferred.

It sounds like you might benefit from using active, powered speakers. Place the speakers where you want and run balanced interconnects to your preamp or high-gain source. Should work great if you haven't yet purchased gear.

Post removed 
Usually more than about 30 minutes then I get too sore. Oh, wait, that’s interconnects. Never mind.
But I always heard (or maybe misheard) that longer speaker cables were a bad idea.

Kind of depends on a lot of factors. I mean, ideally everything is close together, cables never cross, blah blah blah.

The big issue among audiophiles is the big-ass very expensive speaker cables. If you are going to spend $300/ft for speaker cables, but $30/ft for interconnects, the latter is preferable.

I used to work in a theater and we had up to 150' from amps to speakers. Worked fine. Was it ideal? We could have put the amps behind the screen, but then we'd have 150' of signal cable, which, even when balanced, is MUCH more prone to noise pickup than speaker cables. And I don't mean your reviewer sitting at home with a glass of wine type of splitting hairs about blackest black backgrounds, i mean NOISE!!!

So, honestly, think about the subtle 'notes' you may change with longer amp cables vs. convenience of wiring the whole thing.

Best,

E
There have been a number of threads here in the past on the question of long interconnects/short speaker cables vs. short interconnects/long speaker cables. My perception is that a majority favor long interconnects/short speaker cables. But as with many things in audio it depends on the specific equipment and the specific cables.

Generally speaking the following factors tend to reduce the criticality of interconnect cable length:

-- Low output impedance of the component driving the cable.
-- Use of balanced interconnections.
-- Low cable capacitance per unit length.
-- Insensitivity of the interconnected components to ground loop effects (which is generally not predictable).

Generally speaking the following factors tend to reduce the criticality of speaker cable length:

-- High speaker impedance.
-- Low cable inductance per unit length.
-- Low cable resistance per unit length.
-- Avoiding cables having unusually high capacitance per unit length, as that could have adverse effects on some amplifiers.
-- Low or no global feedback in the amplifier driving the cable, as noise picked up in a long speaker cable might otherwise be injected into the feedback loop of the amp, with unpredictable sonic consequences.

In this case, without knowing anything about the OP’s equipment I would say that it is probable that 12 foot interconnects will not be a problem.

Also, I agree with the earlier poster that there is no need to keep the lengths of the two cables the same. Unless, that is, you (the OP) envision the possibility of selling them at some point in the future, as unequal lengths would tend to turn off some potential buyers.

Regards,
-- Al


@erik_squires But I always heard (or maybe misheard) that longer speaker cables were a bad idea.
Balanced/XLR is better than otherwise, certainly best chance of noise rejection.

Of course, your simplest choice is to run speaker cables that long.
Good advice so far.
XLR's for equipment supporting the AES Balanced standard is the way to go.-Cable coloration is minimized as a result.
12' for speaker cables will introduce more cable coloration than shorter lengths. So, you might want to demo a few different brands, if you are serious about sound.
B
If you have balanced (XLR) interconnects then no problem at all. If you have coax (RCA) connectors then it depends how much noise they pick up from the environment (hum etc), and the ability of the pre to drive a capacitive load. Best advice is probably to give it a go and see. There's no need to match the interconnect lengths, in fact I'd keep each one as short as possible.