Sjöström Audio

http://www.audiophonics.com
Ms. Susan Parker has a collection of rather unusual stuff like a zero-feedback amplifier consisting of only two MOSFET's! She has also designed a loudspeaker made of marble!
http://www.keld.eu/diy
This is Keld's DIY site that contains various projects including my QRP01. Original here.
http://www.lcaudio.com
DIY hifi stuff designed by Lars Clausen. They sell ready made units and pcb's. Not very cheap but on the other hand the quality is high industrial standard, not the common consumer standard.
http://www.parttimeprojects.com/audio/diy
DIY audio projects, including a differential input (buffered) LM3886 GainClone amplifier, an LM4780 parallel ChipAmp, a Krell KSA 50 Clone, a preamplifier, a battery powered differential line driver, a soft start circuit, and a few .wav files of audio...
http://www.tentlabs.com
Mr. Guido Tent's homepage with lot's of good DIY stuff, such as CD clocks and super shunt regulators.
http://twistedpearaudio.com
Twisted Pear has a very nice looking Gainclone and also other stuff like preamps, attentuators, input selectors. They sell kits and pcbs. DAC is also in development.
http://www.weiss.ch/products/op1-bp
A discrete built operational amplifier with of course ultra high performance. It looks real good also.
https://audio-circuit.dk
Jan Dupont has a big collection of schematics and service manuals for all sorts of audio equipment, such as amplifiers and loudspeakers.
http://www.audiosector.com
Peter Daniel in cooperation with Brian Bell has designed this little cute and blue Gainclone pcb. A very nice job indeed. Mr. Daniel also sells pcb's for a good price. At the moment this is the only place to hold of the real gainclone pcb since chipamp...
http://home.pacific.net.au/~gnb/audio/lm4780.html
In-depth technical information about the LM4780 stereo 60W chip and my design log for building audio power amplifiers using this dual-LM3886 equivalent. I also have a detailed comparison of specifications between the LM1875, LM3875, LM3886 and LM4780...
http://www.s-audio.com
A very nice gainclone design with ultra low distortion signed by Nickolay Shvydky. The pcb uses SMD parts and looks very nice, indeed.
http://sjostromaudio.com/pages/index.php/hifi-projects/133-qsxm3-the-extreme-phono-riaa-amplifier
QSX Mark III - The extreme phono (RIAA) amplifier       Click on the picture to get a larger view. The printed circuit board of the QSX Mark III Amplifier. Interesting features In order to get an extremely linear and extremely low distortion design...
https://ptodorov.com/the-blog/
Personal DIY blog of Plamen Todorov. Sharing my DIY builds of solid-state amplifiers, DACs, preamplifiers, cables and other DIY electronics.