Have you ever misplaced your amp cable or forgotten it for a gig and just grabbed the nearest laptop or computer monitor cable? We all have... Should we? Does it matter?
How Important is your power cable?
Something common to electrical devices is that they are usually only as good as their weakest link. What part does the power cable play? We know it brings the power from the wall to the amp, but where the power goes after that may be the most important. Usually the power goes straight from your cable to the input transformer. This is where it is converted into the voltages that the amp needs to work. Commonly there are 3-600 volts for the plate voltage, 5-7 volts for the rectifier, and 9-12 for other circuits. The consistency of these voltages is key to the amps performance. This is especially true when we start playing. As the loads change on the amp, voltages rise and fall, and because of how electricity works, so does current. When the amp requires more current from the wall.... it needs it NOW. If the power cable is too small, it is theoretically possible for it to not get what it needs fast enough and you could hear this deficiency at the speaker.
Can You Hear a Difference?
If I buy a thicker high end power cable will I hear it? That depends. Usually, the higher the tolerance of the amplifier (like high end audiophile or studio equipment) the higher the likely hood of noticing the fluctuation in current (if any).
The voltage tolerances of your amp play a role too. If your amp can handle fluctuations in current under load and still sounds great... You may not hear a difference.
Do I Need One?
If you buy a high quality amplifier from a builder who has engineered his amplifier properly from the wall to the guitar cable... you may already have what you need.
Fortunately, many of these cables are not expensive. It may be worth a shot for experimentation. It is possible you may even have what you need around the house, but BEWARE. It is a law that every cable be marked with the wire gauge on the side. Most computer and monitor power cables are 18awg. You will be no better off with these cables.
The wiring in your house is usually 14 awg. If you want to remove the weakest link in your power chain, look for that number. Remember, if you use a wimpy extension cable after your amp power cable.... you just undid everything. Like I always say... "don't cheap out on your tone"