Okay, I made the mistake of using an instrument cable to connect my JCA22h to an 8 ohm cab with an Eminence Governor. Volume was on 2 or 3, I don't remember. I strummed for about 10 seconds, no sound output, shut it down immediately. Power light on, Tubes glowing, standby was okay(no sound in either position). No "boom" "poof" or "hiss". Absolutely no sound.
What could be the problem? Do I need to use a speaker cable? The shops I asked in, all claimed that instrument cable should be fine. I couldn't find a single speaker cable in any shop. I need one in 2 days, so ordering online is not an option yet. Could there be a problem in the cab? Or is it just the fact that I used an instrument cable? Could I have blown the OT?
Thanks in advance.
I need help. I need to know what's gone wrong....Will the amp work fine if I just use a speaker cable?
This can be a tricky answer.

First note that you SHOULD be using a speaker cable. Instrument cables arent made to carry the wattage so you run the risk of frying the cable which would lead to a short or even worse, a blown OT.

Now, At lower volumes you can get away with an instrument cable. The thing here is, do you know if that cable is good? If that cable has a short in it or has come disconnected you wouldnt have a connection to the cab which would mean no output. Which yes, can cause a problem.

Make sure the cable you are trying is a good cable.

Dont crank it up loud when using an instrument cable due to the reasons listed above.

Hope that helps.
There is no sound output using the instrument cable. Do you think it will work fine with the speaker cable?
If you get absolutely no sound with an instrument cable, then I wouldn't guess that the type of cable is the problem. Can you take them both into a shop or borrow gear from a friend, and try out the head and cab separately? See if the head works with a different cab, see if the cab works with a different head?
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funny because i made the same mistake when i got my dsl100 thought i got one but i didnt have one it was an instrument cable after i looked.

so i went to gc and bought 3 foot speaker cable for like 11 bucks. went home plug her in set it to the right ohm turned it on and it magically worked.

you should be good dude, i was worried too

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