DIY tube amplifier by Stavros Danos

This gorgeous heavyweight SET amp uses the Direct Heated 813 tubes triode connected, runing at 120mA. OPTs are the excellent Sowter SE18 SE.

The filaments power supply uses batteries for eliminating hum.

The main power supply uses a toroidal Amplimo Power transformer (850V secondary), followed by an CLCLC filter separately for each channel using polypropylene and oil capacitors only.

Crystal SET amplifier project by Martin Thibault

What we have here is an acrylic stereo, 5u4GB tube rectified, Single Ended Triode using two 6L6Gb’s as outputs, one 6CG7 and one 12AX7. It’s powered by a Stancor Power transformer I had on hand, one very beefy Hammond choke, and two 5K Edcor OPT’s which are rated at 15 watts.

This is my first scratch built amp using schematics and assistance provided by:
http://sarris.info/main/6l6-single-ended-tube-amp

Of greater importance is the patience and guidance of my very own tube guru, Mike who should be nominated for some kind of electronic sainthood.

A single-ended direct heated triode tube power amp design, by costas sarris

Direct heated triode power output tubes are really interesting. Since September 2008 I've been working in a new project regarding a single ended triode tube power amp using the 811A vacuum tube. Actually it is a project with a long process of experimentation.

The 811A vacuum tube it is a power triode capable to output 10 - 15 Watts in a single ended class A2 configuration, in a three stages circuit using interstage transformer in the driving stage.

It's all about a double project. At first I built a prototype amp using the SV811-3 tube. Afterwards I built another one using the 811A tube in order to offer it as a gift to my friend Scott.

DIY single ended amplifier by Christos Spathopoulos

Even though 6L6 tube is used primary in guitar vacuum tube amplifiers, many manufacturers use this tube in audiophile designs. I decided to build this small single ended amplifier based on 6L6 vacuum tube using a classic three stage single ended design.
The plate voltage is about 320 Volts and the output stage is a classic single-ended cathode follower. Output transformer is 4500 ohms and is set for 8 ohm speakers. We chose this design for one reason : Wiring this tube as tetrode we achieve the greater possible amplification as a result of higher grid transconductance.
Click to the picture below to see more photos and the Schematic.

Project in progress. Please stay tuned ...

Coming soon to a rack near you ! a 6L6GC push pull tube amp with 12 tubes (6 tubes per channel !)
a project by Giannis Spathopoulos

811A Parallel single ended amplifier by George Filippou

This 811A tube amp DIY project designed by George Filippou and Giannis Spathopoulos, is the first attempt to work with 811A direct heated triode audiophile tube.
It is based on Shishido 811A tube amp,and the whole project is still in progress.Power output stage uses 2 X 811A tubes in a parallel single ended connection. Plate voltage is 450 Volts. The driver stage uses the 6L6GC tube and the voltage stage the EF86 tube.
We are working on the PSU boards performing measurements and adjustments.
You can find the Shishido schematics in amp schematics pages and 811A tube data in tube data pages.

DIY tube 807 amplifier by costas sarris

In the summer of 2002 I decided to build a pair of mono block parallel single ended DIY tube amps, using the 807 tube. Actually, that was my third DIY tube amplifier project. It all started with my decision to use the less known tube 807 , a tetrode whose features and sounds I was well aware of, from a specific DIY project (with one tube per channel wired in triode) made by Christos Spathopoulos. Christos’ tube 807 amp played very smoothly in the whole spectrum (perhaps the best sound I had heard until then ) but, unfortunately, it lacked power.
After we discussed my idea with Giannis and Christos Spathopoulos we focused to build a tube amp with two parallel 807's per channel in a cathode follower connection, wired in tetrode - class A, using negative voltage in screen, based to the characteristics according to RCA and SCT...

EL34 amp project by Giannis Spathopoulos

This is Giannis Spathopoulos EL34 amp push pull diy latest project. It is a classic push pull amp design .

It is an ultra linear mode PP amp uses the EF86 (voltage gain) and the 6FQ7 (phase splitter )tubes at the driving stage. The output transformers are hand made (P&K audio). We build this amp in a ready-made chassis.It is all hard wired using silver Teflon cables in all critical paths. Listening this amp our first impression was very good. It has really excellent performance.

Tube power supply project by costas sarris

This project was an attempt to build a tube amplifier power supply for my 6550 push pull dual mono amps. I already had a really ugly tube power supply in my rack and in early 2000 I decided to design and build from the scratch a new tube PSU.

The importance of choosing to use tube rectifiers for the power supply

As we know solid state diode rectifier circuits, are not very effective for tube amps, because they generate fast impulsion that pass through the circuit. Using a full wave tube rectifier circuit for producing direct voltage, we can prevent hum pulsations, and we can achieve more accurate filtering.

EL84 single ended Tube amp DIY project by costas sarris (2002)

This project based on Decware EL84 Zen Amp

Making a low power single ended amplifier has always been in my designing plans. Obviously such a construction requires the appropriate speakers, particularly horn type designs, so that the output of the amp can reach an efficiency satisfying level.
Once at a certain point, I came across the designs of the Decware SE EL84 Zen amp, which had quite good reviews among the tube amps DIY and Single Ended tube amp builders.

Push Pull 6550 DIY audio tube amps by costas sarris (1995)

The idea of building a DIY audio vacuum tube amplifier based on high-quality materials begins in the early 90's. Initially had to answer the question "Classic Push Pull or a Single ended amp ?" So starting the design somewhere in 1994 I decided to design οn a blank piece of paper, a pair of monoblocks push pull tube amps with a power supply in a separate chassis which would not use solid materials but rectifier tubes.

In the first photo appears the two channels of my tube amps DIY design which consists of 2 mono blocks with a tube power supply in a separate chassis.