Played Triple Rec Pretty Loud with Load Mismatch... Question

[2manygadgets]

Hey folks, did something pretty stupid, was moving some stuff around and when I plugged my head back into the cab, I plugged into the 8 Ohm jack on the back of the cab with the speaker cable from the amp plugged into the 16 Ohm side. Didn't realize it, played for about 10 minutes and I wasn't in front of the amp so I didn't realize sound was coming from only two of the four speakers. The sound started to get quieter and when I looked at the tubes, four of the six power tubes were GLOWING RED RED HOT. I smelled something hot (obviously) and a burning smell. I turned off the amp and didn't touch it till this morning. I played it this morning with everything plugged in correctly and it sounds fine which is a huge relief.

Two questions:
1. Any idea if something was starting to fail which is why it got quieter? Like I said it sounds fine now but is it possible that I started to melt something and eventually something will fail because I did this?

2. Always before when I turned on the amp and it's in standby, the footswitch's 'FX' loop button would come on and I would just turn it off because I don't use any effects in the loop right now at home. This morning, no light turned on. I stepped on the 'FX' switch and it lit up and turned off when I stepped on it again but this again makes me worry that I may have done some damage internally.

Any thoughts? There are no Mesa Authorized repair shops for about 100 miles from where I live. Don't want to assume I'm OK even though it sounds fine as of now but also don't want to go overboard and ship it somewhere for no reason.

Am I overthinking this? I do that a lot :lol:

 

[screamingdaisy]

Just to confirm...

Head 16ohm output into the cab's 8ohm input?

The burning smell may have been dust and oil (from people touching the glass) being cooked off.

Mesa's transformers are pretty robust. I've done something similar before and had no issues. The red plating tubes are an issue, but may be unrelated to the impedance mismatch and that both happened together was just a coincidence. In my experience intermittent red plating usually means one of the tubes has something loose internally that temporarily shorts out due to vibrations. Generally, if I pull the faulty tube out and shake it I can hear something moving inside.

 

[2manygadgets]

Yes, you have it right, 16 Ohm from head output into cab's 8 Ohm input.

I played it again last night and everything seemed to be ok. I played for about a half hour and no issues that I noticed.

Thanks so much!

To hear that someone else has done something similar eases my mind.

 

[ryjan]

It can be easy to do.
I check my speaker cable every time before I power up. Ounce of prevention and all that.