The output quality is limited by the quality of the music source input. A nice efficient full range speaker is also very important. Such amplifiers with just one transistor and one resistor from input to output are possibly the best on the planet. Examples are the Pleiades amplifiers with 1 transistor or 1 electron tube.
Great videos on making possibly the simplest and best amplifier on the planet:
These circuits are the basis of all the Pleiades amplifiers.
Pleiades concepts and schematics are open source.
Simple basic audio amplifier - Creative Duck
https://m.youtube.com/watch?v=Mz6W1QTepUE
Also this:
Audio amplifier using transistor:
https://m.youtube.com/watch?v=NG-H0dL3Tto#fauxfullscreen
And this:
Simple 1 transistor audio amplifier:
https://m.youtube.com/watch?v=Qg58rgxx5_8
And this:
https://m.youtube.com/watch?v=0T2TxGYBJzQ
https://m.youtube.com/watch?v=lrctfMl8qQU
https://m.youtube.com/watch?v=y65rIInphtI#fauxfullscreen
And a version of the Pleiades 1 transistor power amplifier:
https://www.flickr.com/photos/photoulia/32210168100/in/photostream/
A Pleiades stereo pair (one transistor per channel) driving the voice coil of each headphone:
http://euroelectron.blogspot.com/2015/10/pleiades-electra-jfet-headphone.html
It is moving how many people are starting to make such simple and elegant Pleiades amplifiers using the minimum possible number of components on the planet. As the father of modern FM broadcasting Bob Orban says, the simplest signal path is the best. [Maintaining Audio Quality in the Broadcast/Netcast Facility - Robert Orban and Greg Orgonowski
See also the Pleiades 2N3053 driving a Philips AD5046N (800Ω). A great full range speaker makes these amplifiers sound unbelievable. All instruments are as if inside the room, especially in mono and one loudspeaker. Amazing bass as the frequency response I'd down to 0, great midrange, smoity extended treble. A so dynamic, alive sound to listener's brain due to the gradual insyanteniius peak limiting [Hamm]. Absolutely no hiss, possibly the quietest amplifier on earth. Everything is class A operation (electrons flowing all the time) even through the speaker as there is no coupling capacitor. So frequency response is to the limit of 0Hz.
See also the Pleiades 2N3053 amplifier operating with 1.2V directly driving the Sennheiser HD580 300Ω precision studio quality headphones.
The circuits can be derived from the Jones amplifier by removing the first stage and keeping only the power stage.
And usually it is the first circuit we ever learn from a good electronics textbook, for example [Storey].
Operation is in class A meaning electrons are flowing all the time.
The first Pleiades one transistor power amplifier was possibly made in around 1996, with an AD140 driving a full range, or array of full range speakers, Sade was singing on CD The Sweetest Taboo.
The Pleiades power amplifier sounds great on electric bass and should too on electric guitar. A Pleiades filter may be needed in parallel with the pickup to cut muddy bass perception. The Pleiadss power amplifier has been tried with a darlington transistor driven by the synthesizer Yamaha TX802 (moded with no output transistors after the op amps). See previous euroelectron posts. It sounded fabulously alive and dynamic when overdriven and the cutoff bias when no note was played, created a noise gate, so no hiss. The bias can be adjusted with a variable Pleiades bias resistor. Attention to thermal runway. A heatsink should be used at higher power levels.
Of course the Pleiades Electra I, II, III electron tube amplifiers directly driving headphones, the headphone voice coil being itself eithe anode load or a cathode resistor, sound amazing. What has not been tried yet is driving the wonderful Philips AD5046N 800Ω speaker on the anode of an electron tube such as EF183, 6C4, EC92 etc with Pleiades bias from a fairly high MΩ anode to grid resistance to lower the output impedance and using 12-47? volts?. Attention to any voltage, all safety precautions should be followed.
It would be nice if a video showing how a Pleiades V6 microphone booster one electron tube battery powered amplifier is created:
Canelina is happy.
References:
2 transistor miniature AF amplifier - K. Jones - page 41 - Audio Amplifiers - J. R. Davies - Data Publications
Ltd - London
Electronics, a systems approach - Neil Storey
Transistor Audio Amplifier Manual - Clive Sinclair - Bernard's radio manuals
http://euroelectron.blogspot.com/2015/10/pleiades-electra-jfet-headphone.html
Tubes vs Transistors (vs op amps), is there an audible difference? - Russel O. Hamm - Jurnal of the Audio Engineering Society
http://euroelectron.blogspot.com/2014/07/pleiades-electra-jfet-amplifier.html
See also the use of single ended amplifiers in music industry for example the Neve microphone preamplifier with one 2N3055 transistor at the output stage. See also a suggested example of the Pleiades 2N3053 amp inside echo or reverb chambers. See also the hi end electron tube single ended class A amplifiers.
http://euroelectron.blogspot.com/2015/10/pleiades-electra-jfet-headphone.html
No comments:
Post a Comment