Does USB cable length make a diference?

I seem to recall reading that 1.5 meters is an ideal length. That’s what I went with. A cable that I liked happened to be available used in that length.

I've always heard that girth was more important. But I digress.

Not in my experience. The quality of the interconnect. I spent about ten years upgrading my headphone system from basic PC and iPod then streamer to high end headphone amps. The quality of the interconnect made a very big difference but not the length. 

Sls833 is correct, 1.5 meter is ideal for USB.

The standard meter covers all bases