Has anyone worked with this IC? Digikey lists it as obsolete, but has ~500 in stock, quite cheap—$0.91, $0.75 in quantities of 10+. My (not-very-educated) guess is that it isn't very good, but the datasheet says it can put 2.5W into 8Ω, with an 8VDC supply, so I wondered if for the price it might be fun to experiment with.
The great thing about DIY practice amps that run off 9V power is that there are so many to choose from! (The other great things are that they're inexpensive and usually fun and easy to build, of course.)
Off the top of my head:
The aforementioned Honey, of course, which I had a blast building. (and I'd definitely be interested in a Honey II with a different IC!)
I got started with runoffgroove.com's Ruby, and their Little Gem mkI and mkII are also worth a look. They have some mod suggestions for their designs, as well.
Bruce Zinky's Smokey is as simple as it gets, it even omits the Boucherot cell from the LM386 datasheet's "minimal" schematic. (The Noisy Cricket page I linked also shows a couple of simple Smokey mods.)
At the other end of the spectrum, Electrosmash's 1wamp crams in all kinds of features. Looks like kits/PCBs aren't currently available, but full schematics, KiCad files, etc., are hosted on their forum.
Anyone familiar with this one? I came across it a little while ago, though judging by the forum posts it was published back in the early '10s. It's another LM386-based design, a bit more complex than the Honey, with a very thorough article breaking down the design and math for each section. The author even includes Teemu's book in the list of references at the end: https://www.electrosmash.com/1wamp
Photos of the build—I have a couple of these Trader Joe's tins, which I kept because I like the shape and size, a little more room to maneuver inside than an Altoids tin. I used some nylon standoffs and screws to hold it off the metal, which works well enough.
Finally got a chance to actually build the kit! Kudos to Joe for a really nicely designed PCB, soldering it all up was a snap. I'll post a couple photos when I get them off my phone; I wired up the speaker outputs to a Speakon jack and the power supply connections to a 2.1mm barrel jack. I have a couple of cheap small speakers, and a proper 10" guitar speaker as well, and both a 9V battery clip with a 2.1mm plug and a 12V wall wart, so I can swap things around and compare.
I used to hang out on here, many years ago, though I lurked more than I posted, so when I got the email about the Kickstarter launch, I was thrilled to back it. My kit arrived yesterday — thanks @joecool85! — and I'm excited to start work on it soon. I'm curious what other folks are planning for enclosures!
This thread's been dormant for a while, but I guess it can't hurt to ask...
I picked up my old Crate GX-20M from my folks' attic over the weekend, after not even thinking about it for about a decade, and now I'm thinking that I'd like to know more about its guts, and possibly look into some modifications. Teemu, from your post it sounds like this might be a model that falls in the range of schematics you mentioned; if you've got it in convenient electronic form and wouldn't mind sharing (or if anyone else does) I'd certainly appreciate it.
(I wasn't sure whether this should have gone in the main Amplifiers section instead, but I think it's a newbie-ish enough question...)
I've noticed that although the Ruby uses only a 100nF, and the Little Gem and Little Gem 2 don't use any at all, some cursory Googling suggests that a 10uF or so cap from pin 7 to ground on the LM386 goes a long way to reducing noise, and I see that (for example) n9voc tends to use them in his schems. Is there any reason not to add those in to the Fetzer-Little Gem MkII I'm building?
For the speakers I've been looking at, Jensen MODs, at least, http://www.tubedepot.com/ has better prices than most other places I've looked. I haven't actually done any business with them yet, though, so take that with a grain of salt unless someone else knows more about them...