Would this work for two conductor power cable?

I know the benefits of a three conductor grounded power cable but IF I use a two-conductor to replace the stock cable on my tube amp would the following be a good alternative?

First, I've read that a shielded cable is not necessary for analog equipment (such as my tube amp). I don't know why, or even if this is a correct statement.

If it is true, then I wondered if good quality loudspeaker cable - in an appropriate gauge - would be suitable as a DIY power cable?
NO. Do not use a wire not made for A/C in a power cable. The insulation is the thing.
If it is not rated for 120volts, it will fail. And most speaker cable does not have a good enough insulation for A/C use. The reverse is not true. You could use any A/C cable for speaker cable and be OK.
Most A/C wire insulation is 300 volts. So it can be used for 240 volt applications. Most speaker cable is way less, probably rated to 30 volts,(a guess, but somewhere around there) tops.
So do not do it.
AND; if the original cord was grounded you need to use a grounded three wire A/C cord. Tube amps have lethal voltages (300volts, big amps too.) in them and taking the ground off is plain stupid.
Thanks Elizabeth, I hadn't thought of the insulation at all as I was concentrating on the wire gauge; so I won't use it.

I wasn't going to take the ground off my amp. It is only a two-conductor device at the moment.