I can be as dumb as a rock sometimes.

[pinkphiloyd]

I threw an amp together out of just spare parts that I had laying around. I have spent the entire day going through it, repeatedly, trying to figure out why it wasn't working. Ten minutes ago, I realized that instead of plugging the speaker cable of my super reverb, which I'm using for a cab, into the back of the amp, I have repeatedly, all day, plugged the amp into the speaker out jack of the Super. All of a sudden, it works like a charm.

[Koop]

Ouch! No load, glad to hear it's working fine.

[Luthierwnc]

I had a similar problem with an amp I sold. It was a Route 66 clone -- nice amp but I had something similar that won the battle. I sold it on EBay for about the cost of the parts. The guy who bought it gave me a nice feedback score and then found it didn't work. He kept emailing back and I was replying what it might be on the amp. Towards the end he got a bit adversarial. I was ready to buy it back since I hadn't gotten a great price anyway.

It turned out the speaker jack on the cab was open. Then he wanted to know why the amp sounded weak after he had been driving it into an infinite load on 10 trying to get noise out of the thing. My final reply was that he was lucky he hadn't incinerated the OT but had surely barbecued the KT66s. I'm not sure how I didn't ream him a new one for getting pissy when his cab was broken but I was remarkably civil throughout. It was the third draft of the reply, though.

I've done things equally stupid but I'd much rather fix the problem in the shop than do customer service over the internet. sh

[timford]

Best thing is you won't do the same thing again next time.......or if you are like me, it won't take as long to work out next time.......

[pinkphiloyd]

I blame habit. For the last few years I've used an Avatar 2x12 cab so I'm just in the habit of running a cable from whatever I'm playing/building/testing into a 1/4 jack on the back of the cab. When it hit me, it was really one of those "what a dumb-ass" moments.

[Reeltarded]

hahah no way. I never did anything like that. Ever...

Imagine a patchbay with hundreds of tiny cables. 5 colors, 9 double rows. Things can happen. Then again, it might be the patches in the live room. Umm check those before relacing!

Then there are those couple times where I am freaking out for ten minutes and remember that I pulled the preamp tubes twenty minutes ago.. oh yeah.

[Firestorm]

How is the Super? When you plug in that way, you're actually driving the Super OT's secondary backwards into an essentially open load. I have no idea how a transformer feels about that.

[Cliff Schecht]

I recently buttoned up a 5F6A build and tested it at the house. It had the usual big punchy cleans and such (used a black plate 5-star 6072A in there, nice tube!). For whatever reason that tube ended up getting pulled and temporarily replaced with a 12AX7 of some type and I completely forgot when I took it to my buddies shop to show it off. The amp was overly gainy and got a flabby distortion when cranked. Of course I forgot to change out that tube again before band practice and when I flipped on the amp it started chirping intermittently at me very loudly. Everyone got pissed at me and I played through practice on the Express with my tail tucked and my pride hurt. I thought the amp had developed a bug somewhere in transit. Today I put that 6072A back in and the amp sounded killer...

That's just the tip of the iceberg of course. I do dumb shit all of the time. I think the more trained one is the more likely they are to make a simple mistake that is so incomprehensibly dumb that they automatically overlook it. It's always the simple things that get ya!

[Luthierwnc]

Yeah, the dumber the thing, the more likely you are to overlook it.

I use my variac at about 90% to run the heat blanket in my guitar side bender. Leave it at that setting and spend a couple hours wondering why your bias is so far off! sh

[Structo]

I had a speaker cable that coincidently developed an open when I was working on an amp.
I had done some mods and then plugged it back in and had no output.
Zip, nada, not even any hiss or hum.

I scratched my head about that for a few hours.
I was ready to pull the OT and check it out more thoroughly when on a whim I tried another speaker cable.
Doh!

Luckily I didn't seem to damage the OT.

Moto to this story was to buy a couple high end speaker cables and always start with the obvious before tearing things apart.

Start from the problem and work backwards.

[xtian]

always start with the obvious before tearing things apart.

Right! My favorite distilled wisdom from years of helping retirees with genealogy software on DOS and Windows 3…"Is it plugged in?"

[pinkphiloyd]

It's always the simple things that get ya!

Yeah, the dumber the thing, the more likely you are to overlook it.

It's like my calculus prof in college always said. "You might want to check your addition."