Your outstanding design will certainly improve the sound of your equipment, whatever that is.
Set aside it does not use global negative feedback (a well known sound killer, due to the high order harmonics and PIM impact) it's excellent sound is also the result of the very low output impedance up in the MHz range and very good load and line regulations.
This sort of design has been used since bipolar transistors first came available in the 1950's. It is often considered too simple and imperfect, however it has a number of advantages that make it useful, even today.
Personally, I first used it to IMPROVE an existing commercial +/- 15V supply by using this very design, WITHOUT the Zener diode, (since DC regulation was already established) in the Levinson JC-2 to lower the power supply noise to the phono stage, which, while balanced, had modest power supply rejection.
That was 1973, however, you will find it in almost exact form (with the Zener) in many Parasound power amps of my design over the last 20 years. I do often swap the bipolar transistor for a power mosfet in my better designs, but the circuit is basically the same. It is also true for the CTC Blowtorch, the Parasound JC-2 preamp, and most preamps (without the zener) that I have designed over the decades.
Personally, I first used it to IMPROVE an existing commercial +/- 15V supply by using this very design, WITHOUT the Zener diode, (since DC regulation was already established) in the Levinson JC-2 to lower the power supply noise to the phono stage, which, while balanced, had modest power supply rejection.
That was 1973, however, you will find it in almost exact form (with the Zener) in many Parasound power amps of my design over the last 20 years. I do often swap the bipolar transistor for a power mosfet in my better designs, but the circuit is basically the same. It is also true for the CTC Blowtorch, the Parasound JC-2 preamp, and most preamps (without the zener) that I have designed over the decades.
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Maybe I lost track, but are you guys still talking about Joshua's emitter follower or have you switched to a real regulator?
jd
Thank you very much for your comments, now I'm illuminated. However, my question referred to the differences between IC regulator vs. discrete one. Do you have any comment to that question, or you'd be satisfied by only mocking others?
Joshua, it can be debated whether you need to add the .1uf cap across the Zener. The Zener diode has its own internal capacitance and works well into the RF region. Everything else looks OK.
This sort of design (without Zener) is used with 'real' IC regulators and are normally known as capacitor multipliers. They can be very quiet. Adding the Zener, and resistor reduces the 'breathing' from AC power lines and its potential compromise to the circuit, IF you do not use a 'real' regulator in front of the cap multiplier.
It is best to keep the channels separated by using a cap multiplier for every channel, and even every gain block, in an audio preamp or power amp driver stage. This is because the output Z of the regulator of this kind, while being broad-band, is fairly high, even a few ohms, especially if you add short circuit protection in the usual way. The Levinson JC-2 suffered from this.
This sort of design (without Zener) is used with 'real' IC regulators and are normally known as capacitor multipliers. They can be very quiet. Adding the Zener, and resistor reduces the 'breathing' from AC power lines and its potential compromise to the circuit, IF you do not use a 'real' regulator in front of the cap multiplier.
It is best to keep the channels separated by using a cap multiplier for every channel, and even every gain block, in an audio preamp or power amp driver stage. This is because the output Z of the regulator of this kind, while being broad-band, is fairly high, even a few ohms, especially if you add short circuit protection in the usual way. The Levinson JC-2 suffered from this.
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Thanks, it's a low current transistor, therefore not suited for a regulator.
We have the same equipment in the avatars
could not resist taking the photo, gave the 54750 a lot of work today
2*54751A, 1*54752A + some that are cannibalized for samplers
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could not resist taking the photo
I was to lazy to take a picture of mine, so the current picture is stock. I have one 54721A and 2 x 54712A.
I gave the link to help you see the difference. If you don't want to, that's not my problem. I'm done giving free consulting here.
jd
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