Do speaker wires have to be the same length for each speaker?

Mitsy says: "Are you kidding? Of course not!":

 

And, Mitsy can hear up to 45Khz. 

Hey Christian:  Hi they are not the same length because one speaker is +/- 10 further from the equip. The stereo is in the corner of the room due to fireplace location, sliding doors, etc... Also the wire to that far speaker goes under the house so that adds a few feet as well.

Ah - so custom install, not quite full in-wall, but close.  Yes, no issues with differing lengths.  I've said before I have a tough time discerning differences between cables, but if say you have your audio rack on the outside edge of once of the speakers (which I thought was the case), why not buy an identical set, and just coil/drape/suspend/whatever the cables over to the speakers.  If anything, as said before - it would help with resale, but I figure you won't be reselling the underfloor wire anytime soon.  Sounds like you've got a fun project ahead! 😃

Funny thing I've done a lot of auto/equipment installs for stereo gear. I use to cut and trim all the extra wire. Nothing was the same length.. Butt connectors everywhere then shrink and zip tie everything.

Same here - I started doing my own car audio custom installs in college (were those the days!) - underseat/trunk/dash mounted amps, and wires of way too varying lengths going all over the place.  It's probably the OCD in many of us when I got into the home stereo listening craze (er- wife calls it a disease): a pair a speakers, audio rack in the middle, and EQUAL length cables. 😋

Again, not sure if I could tell the difference if one side was longer than the other, but it wouldn't "sit" right with me if they were differing lengths. 

In the mean time… one highly recommended speaker cable to consider (let’s see if I can get this right); HD12-3? Years ago either Stereophile or the Absolute Sound did a comparison of a number of low to intermediate speaker cables. They threw in a Home Depot extension cord… ends cut off. It actually sounded pretty good… didn’t win against $1K cables but sounded way better than lamp cord and Radio Shack 18” gauge speaker wire”. I loved the article it was great fun and informative. While I use $5K Transparent cables on my main system. I use HD12-3 on my office system… hidden because of the orange and black color behind my desk.

Sounds like you have a mold problem, ghdprentice. Just kidding... but are you serious about using an extension cord? It’s about $80 for 100 feet on Amazon; for about $10 more, you can get nice 10 gauge real live speaker wire.

Some speaker wires are custom cut and terminated/soldered and I guess if it was expensive enough you could save a few bucks with different length cables.

However I have OCD when it comes to my stereo with everything being lined up perfectly, no cables touching each other or the floor, etc., so for me they should be equal because there is some electrically measurable difference with different lengths that is not audible, but still "there". That's enough for me. I am sure we've all bought something that was supposedly better that we paid extra for that is not audible or detectable as an improvement individually.