Some of you who’ve been reading this blog for a while might recall I’ve been playing Dr. Frankenstein in my basement, building a replica of the legendary Marshall 18-watt amplifier. You can catch up on the story here:
Day 1 – The start of the project.
Day 23 – Loopy from solder smoke, I have a mystical vision.
In February, with the wiring completed, Al “Igor” Scott and I tickled the beast to see if it’d twitch. Well, it twitched.
I’ll let Al tell the story. This is an excerpt from a post in response to people asking how the amp project was going:
Hey everyone, Rob DID finish it. And I took pictures when he switched it on. The thing smoked, caught fire and then burned the house down. It’s all on film. How come you don’t post it, Rob?
No….. That’s not what happened.
There was a loud piercing squeal. Like a smoke alarm going off. So we turned it off and looked at it. Hmmm. All the knobs were turned down. So we put them half-way up. Turned it on, squeal gone! Could it really be that simple? Seems it only squealed if the tone pots were all the way down. So we centered them. Pure silence. Blissfully hum free.
Rob got the Les Paul.
He turned the volume up full.
And the most gorgeous sustained distortion poured out. Rich, detailed, articulate, phat. Like that first taste of beer on Friday. Like butter on pancakes. Like sex with everyone you’ve ever dreamed of. At once.
And when wild man Rob held the guitar to the speaker (the way you know he likes to) the feedback careened out just like it does on TV!
We were in Rob’s basement, and just then his girlfriend arrived and said she heard it from the street. “You guys having a party?”
It was at this point that I noticed the 18 Watt has no gain knob. Just volume.
“Right,” Rob said. “You want distortion, you gotta play loud. Like our forefathers did.”
So we kinda did burn the house down after all.
Now Rob seems to be in the midst of figuring out the cabinet issue. I’ll let him post about that.
Uh, Rob? Can you stop singing and finish the amp?
Here are some videos of the Moment of Truth:
Baby’s First Scream – It turns out the 18-watt design I used sometimes has a “ground loop” problem when the tone or volume pot is turned all the way off. I solved the problem by grounding the volume knob to the chassis.
Baby’s First Power Chord – After months of soldering in silence, this was a sweet, sweet moment.
Since that evening, the amp has sat cold and silent on my workbench while I mulled over the question of the cabinet. Hardwood or tolex? Handmade or profe$$ionally built? On 4/27, I finally ordered a cherry cabinet from Weber Speakers, which has an 8-10 week wait for all hardwood cabinets.
Every time a UPS truck passes my house, I jump…