Tag Archives: 386

Sam’s LM-386 Amp, a picture of my workbench, and blue tubes.

sams cigar box amp

Sam’s non-cigar box amp

My brother-in-law came over because he wanted a cigar box amp. He also wanted to build his own enclosure, and I think it looks superb. It sounds great, too. With the limited sound holes and a totally enclosed box, it creates low end and crunch like no regular cigar box. I am including a picture of it just to show it off. He had some great workmanship. I believe he used 3/4″ plywood, which he didn’t quite like because it chipped every time a tool came near it. He painted it with eight coats of black paint and then furniture polished it.

The second order of business is that I left my guitar amp in a public place and somebody thought they would play it. Well, I’ll be if it didn’t start glowing blue. I guess the sound is okay, but I’ve never seen my tubes glow blue before. I’ll probably

6DG6 (6DG6GT) tubes glowing blue

6DG6 (6DG6GT) tubes glowing blue

buy some new tubes for it in the near future. They’re pretty inexpensive. It’s the shipping that kills. This is the tube amp that I built using the featured tutorial on Instructables. I’ve talked about it before. If I could really wail on some guitar, I’d make some recordings of it. Dreams and arm pits.
Here’s the picture of the 6dg6 tubes glowing blue. I really like how it looks. It’s a beautiful sight to me, and if they weren’t so stinkin’ hot and if the amp wasn’t so big, I’d just leave these babies glowing as a night light.

I really love that!!! They only glow blue when the HT is on. I’ve read conflicting reports about blue tubes, but I really don’t have a professional opinion of my own. It’s mainly credited to impurities in the vacuum. Either way, I’m not to worried about it. Tubes go bad. Big deal. It’s an opportunity to buy presents for my amp. :) (I learned from a reader that blue tubes are okay. Thanks to Kent L. for emailing me about this. In short, Kent says that blue along the envelope is a sign of a good vacuum. 10-22-2012)

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