Vacuum Electron Tube Valve Preamp Amplifier Board Headphone Amp Parts Musical Fidelity Kit, 6J1 Audio Tube Headphone Amplifier, Compact Electronic DIY Kit DIY Parts (Static Bag)

Came with all components, glass tubes intact, works great. Was hard to find a cheap 12VAC power supply but I found a 750mA one for five bucks and it works fine. The flashing RGB LEDs make cool interference sounds. I am using this for guitar, intentionally trying to get distortion, so I don't care about audio quality. It sounds and works great for that though! Doesn't fit the other clear plastic case I found, some minor drilling fixed that though.

Outstanding! My love for kit building started in 1963, when I was young and out to prove that a woman could do anything. Not being overly domestic, I quickly developed a love for soldering. I've soldered on stained glass...built an Heathkit stereo FM receiver, a small FM radio, and now this pre-amp. It took a day to build this pre-amp, and the end result is awesome. Coupled with an inexpensive amp I bought from Amazon and a couple of small speakers, the sound is amazing!!! Although there were no instructions, the pcb was well marked so no written instructions were needed. If you're looking for a fun project, I highly recommend buying this kit. You won't be disappointed.

First off the plastic case is sold separately which was a slight bummer. I did end up buying one. I tried running it initially off DC 12v which is what most power adapters are. Was quiet and distorted. Figured out I needed 12v AC and got the correct adapter and it worked. The 2 best cheap mods I have found: Either replacing R14 and R19 with 100ohm resistors or just soldering a 220 ohm resistor on the underside of those supplied two resistors. This slightly opens up the sound stage and raises the volume some. Replacing C10 and C12 with 10uf caps or just bridging the originals with 10uf caps does really help the bass response like another review said. Also getting a matched pair of GE tubes helps improve the sound over the cheap ones supplied. This will cost you about as much as the kit though. With a nice set of headphones this little preamp does sound quite good. That resistor mod to R14/R19 really helped give the volume I wanted on my headphones. They are 40ohm speakers and I doubt you would get near the needed volume on any headphones of much higher resistance.

Lot of fun i will buy more !

Not the easiest build due to no instructions or schematic but sounds great for the price.