Tiny tube amp for headphones

We like to check in from time to time on the scratch-built tube amp scene. [Rogers Gomez] recently posted his build of a headphone tube amp. This is somewhat related to his work from 2008, but this time around it’s simple enough to serve as an entry into amplifier construction for beginners. The PCB layout is clean and simple, makes for easy board etching, and it’s small enough to fit into an enclosure that can pass as a headphone accessory. Only one tube is needed, with a total parts bill coming in around the $50 mark. If you build it, heed his advice on testing with a pair of cheap headphones before you risk plugging in your prized pair.

Still want an amp but don’t care to source the vacuum tube? [Giovanni], who sent in the original tip, build one a while back and housed it in an external CD-ROM enclosure.

72 LED persistence of vision globe

HaD-pov-globe

[Ben] told us about his POV globe yesterday. We took a look and saw just one photo and the code with no real explanation of his project. He certainly set to work over night and now we see all the goodies we look for in a great build log. He even threw the Hackaday logo up for our enjoyment. His build is well executed and he found some creative ways around the common problems in these projects. We take a closer look after the break. Continue reading “72 LED persistence of vision globe”

Hybrid headphone amplifier


[Rogers Gomez] has posted up this hybrid tube based headphone amplifier over at DIY Audio. Being a fan of tube amplifiers, but wanting something with lower voltage and lower cost, he put together this little system out of spare parts he had lying around. He wanted it to have as few parts as possible and be able to power his 32 ohm Grado headphones.

He states that he’d built several YAHA amps, and a Szekeres Mosfet follower and was curious how they’d sound together. He was pleasantly surprised with the resulting quality.

There are less than 30 individual components involved in the project. The complete parts list and schematics are available from the site. He notes at the very end, to unplug your headphones when powering up as there is a surge that could damage them. That might be good to know at the beginning just in case you get eager to test it out.

[Thanks, Gio]