Singleended triode set amplifiers have a cultlike following in audiophile circles, but their limited power output has limited their usability. The use of a single tube in the output stage of the power amplifier is commonly referred to as a single ended design. The configuration is built around two standard tubes viz. Whats so irresistible about a singleended triode set amp. You can use el84s if you like but i prefer the russian 6p15. This venerable circuit topology, essentially the simplest possible tube amplifier, has reached almost cult status in todays audiophile circles. They are usually used for relatively small amplifiers, e. This is a low power guitar tube amp suitable for practicing, recording or miking through a pa system. The trex set amplifier a diy project article by dick 1set class a single ended 6550 5z3p tube audio amplifier diy kit. Atarashi designed this amplifier for the multichannel sacd application with just fourchannels instead of the normal five. This is only one set kit, you need to assembled by yourself. Kt88 single ended tube amplifier build 2018 part 1 youtube. Recently added speakerheadphone switch and headphone jack.
According to the specifications for a type 45, operated as class a single ended amplifier, with 275v max. If youre interested in making your own amplifiers and have never worked with high voltage before, be sure to follow correct safety procedures. Back in the 1930s, there werent home theater systems and when you did go out to the theater what you heard was usually a mono signal, but it was single ended and the sound came out of a horn. The most popular highend tube amps in the market top. From schematic to ordering parts to cab design, it is all here and explained in detail. Diytube 6l6 clementine single ended tube amp shannon parks, owner of diytube, has made a number of projects available since 2003 when the diytube st35 clone was made available. Dc circuit, circuit diagram, electronics storage, electronics projects, electronics gadgets, speaker box design, valve amplifier, electronic schematics, ham. We must first wear our scientist hat before we can wear our artists beret. I have some 6n7 g and 6cb5 with and without a, so the choice was easy, with the the good reputation your version has. 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. We suggest that you only use tubes that yield good test results for the best amp performance. This amplifier can be easily modified for balanced inputs xlr and will provide 20db of voltage gain. Single ended tube amplifier build 2017 part 1 bg096 youtube.
The author chose the 2a3 directly heated triode power tube to implement the loftinwhite circuit. Single ended amplifier simply require much more care in design than pushpull designs. Single ended 6550 tube amp schematic with 12dw7 driver stage. The output transformer primary is not centertapped, having only two connections. I used salvaged transformers purchased well below online prices and 807 tubes which are still reasonably priced. This design was chosen for its relative simplicity compared to the more. The new diytube getsetgo single ended triode amplifier. The human voice reproduced through a single ended amplifier can be spooky realistic, but it requires a specific quality of speaker to truly appreciate. My first diy headphone amplifier was based on this lovely pentode and i also still have a decent supply of them, so i wanted to try this tube in a transformer coupled single ended schematic. Even though 6l6 tube is used primary in guitar vacuum tube amplifiers, many manufacturers use this tube in audiophile designs.
To improve the power supply a 5 to 10h choke can be used in place of r11. The amplifier is based on mikael abdellahs single ended kt88 tube amplifier circuit. A schematic and the design details of this amplifier are available in mullard circuits for audio amplifiers book and in the national valve museum article. The circuit is so simple i use it in my how tube amps work webpage. Single ended class a 6v6 6j5 valve vacuum tube amplifier circuit. The circuit is derived from the classic single ended designs that began in the 1930s. Input circuit when the 3500z is operated as a groundedgrid rf amplifier the use of a resonant tank in the cathode circuit is recommended in order to obtain greatest linearity and power output. Schematic of the loftinwhite single ended tube amplifier.
This design has been optimized for low distortion and high efficiency with no negative feedback or any sort of servo correction circuitry. The amplifier is built around mullards double tetrode ecc83 tube and beam power 6v6 output tubes. A singleended triode set is a vacuum tube electronic amplifier that uses a single triode to produce an output, in contrast to a pushpull amplifier which uses a pair of devices with antiphase inputs to generate an output with the wanted signals added and the distortion components subtracted. In this article a typical single ended tube amplifier circuit has been conversed. Afterwards i built another one using the 811a tube. The preamp circuit and features are similar to those on a fender tweed era princeton. Bg157 new series on how to build a kt88 single ended amplifier. The last thing you want is to have that moment of regret when you install a new tube amp and find that you overpaid when a cheaper priced model would have had all the same features. The adjoining circuit diagram shows a full fledged stereo. Kt88 tube power amplifier class a single ended valve triode amplifier has not same tone with push psu amplifier. The 2a3 tube amplifier a tribute to simplicity and warm. The unit also represents, perhaps, the worlds first single ended triode home theater system. I have built a few of these amps and find them an excellent and inexpensive amp. Singleended octoblock tube amplifier hifi tube amps.
The guitar signal on the upper power tube grid changes the current flowing through the tube which causes a voltage. The two biggest disadvantages that many single ended amps have are bass and power. One connection goes to the power supply, the other to the plate of the power tube or tubes. Now, 2ohms is staggeringly high, as is the 4 ohms presented by some singleended tube amplifiers, when compared to solidstate designs, but it is trivially diminutive when compared to infinite ohms, which a true currentoutput amplifier would present as its output impedance. It uses a single pentode stage for the preamp, a selfsplit pushpull power amp which requires no phase inverter and a field coil speaker. The plate voltage is about 320 volts and the output stage is a classic single ended cathode follower. The sound has the right touch of sweetness to give the tone of the tubes but without.
The sound obviously i am quite biased, but the amplifier has the sweet sounding treble performance of a good single ended amplifier. A singleended guitar amp output stage is generally biased class a, in order to maximize the output power before distortion. If this is your first visit, be sure to check out the faq by clicking the link above. You can get a circuit board from them or you can build it point to point. These amplifiers are entirely hand made right here in chicago, with love. Time tested, simple tube single ended stereo amp delivers that important first sweet watt that audiophiles love. Lone wolf blues company single ended 6l6 circuitry. The power amplifier involves three stages, two of which use a 12ax7, and the last of which runs through an el34 pentode tube. Open, detailed mids and highs, with good bass extension belying the low overall output power. Over 90% of amplifiers are push pull, and push pull amplifier does not 2nd harmonic and off course. I decided to build this small single ended amplifier based on 6l6 vacuum tube using a classic three stage single ended design. Only one linear circuit topology delivers the appropriate characteristic, and that is the single ended amplifier. Single ended amplification only comes in pure class a, and is the least efficient form of power stage you can reasonably create, typically idling between three and five times the rated output power.
The circuit is directly coupled to the srpp input stage. A linear power supply using bridge rectifiers is used for the singleended 6550 tube amplifier. Most of them show these audio beauties used in the pushpull configuration in order to obtain the greatest efficiency and the most power output. Buying a single ended tube amplifier may be an easier option, but building it at home can be fun and amusing too. Theres no better guitar amp to start with than the fender 5f1 champ. Why buy a single ended tube amplifier when you can build one. In an effort to give a little back to the internet harp and tube amp communities, i have decided to offer this free project.
The 2a3 vacuum tube is a power triode capable of outputting 3. Building a single ended el156 tube amplifier this post is from my original jenison audio website which is now sadly extinct. Single ended tube amplifier build 2017 part 1 bg096 duration. Kt88 single ended amplifier is just like good triode amplifier sound and good bass. I have met several musicians who not only fix their tube amplifiers, but modify them, without any deep knowledge of how tube amplifiers works, let. Superb set sound, and available as an easy to assemble circuit board, with parts sourcing information, or i.
Ecc83 and 6aq5a which is able to produce a good 6watts of unclipped power. To start viewing messages, select the forum that you want to visit from the selection below. Kt88 tube power amplifier class a circuit wiring diagrams. Diytube is both shannons small business located in central illinois and a closeknit forum featuring a handful of helpful and prolific members. Thoughts and opinions of a tube audiosingle driver junkie. Diytube 6l6 clementine single ended tube amp diy audio. Normally, single ended output transformers have an air gap and much bigger cores than pushpull transformers rating for the same power handling. Singleended stereo hifi tube amplifier hifi tube amps. Here is your opportunity to explore the possible answers for yourself, at very reasonable cost.
The idea for the amplifier started from the authors discovery of the loftinwhite circuit. Higher powers are obtainable with either very large power valves, or by using multiple valves in parallel. The transformer ratings shown in the schematic are minimums. This amplifier was originally featured on the january 2004 issue of the highfidelity audio. Single ended tube amplifier build 2017 part 1 bg096. The project details the build of a singleended 6l6 harp amp. El84 parallel single ended power amp art of sound forum. Weve done the work for you and found 5 of the most popular high end tube amps on the market. What is it about this circuit that commands such a loyal following. Talking about the considerations of building a single ended tube amplifier. Plug your computer, cd player, turntable, wireless system click here to see the dayton bluetooth receiver, or virtually any other sound source into this elegant circuit and enjoy eight watts per channel of beautiful listening pleasure.