Yes, correct Gareth, Nico is extremely smart AND experienced. However, you are smart too, there are heaps of smart guys on the forum, but as they vie for limelight it is difficult to love all of them......... I have lost a good deal of my verbal skills in recent years so I keep out of it these days. Besides, what is the point?
Hugh
Hugh
Nico I only have one one of these power supplies that I've been using on this build. Evidently one is not enough... 🙁
No problem 🙂 As Nico says, we all had to start somewhere, and I remember my first CMOS logic project (tone generator) where I hadn't realised the 4011 chips needed to have the power supply connected to pins 14 and 7 for it to work. I thought it all worked from the just the pull up resistors and so on. The PSU connections to the chip weren't obviously shown (lol).
A few have suggested the original JLH69 which would be ideal and imo, a better overall design than the later DC coupled ones.
> a better overall design than the later DC coupled ones
If you enjoy the sound of coupling capacitors at input and output. 🙂
Patrick
If you enjoy the sound of coupling capacitors at input and output. 🙂
Patrick
Everyone to his own liking, that's the beauty of DIY. 😉
http://www.diyaudio.com/forums/solid-state/3075-jlh-10-watt-class-amplifier-31.html#post1111310
"Design (including electronic or eletro-mechanical) is always a matter of personal choices. There is no absolute truth, just personal preferances."
http://www.diyaudio.com/forums/solid-state/3075-jlh-10-watt-class-amplifier-29.html#post942914
http://www.diyaudio.com/forums/solid-state/3075-jlh-10-watt-class-amplifier-33.html#post1480779
http://www.diyaudio.com/forums/solid-state/203431-all-fet-jlh-class.html
All DC coupled.
Cheers,
Patrick
http://www.diyaudio.com/forums/solid-state/3075-jlh-10-watt-class-amplifier-31.html#post1111310
"Design (including electronic or eletro-mechanical) is always a matter of personal choices. There is no absolute truth, just personal preferances."
http://www.diyaudio.com/forums/solid-state/3075-jlh-10-watt-class-amplifier-29.html#post942914
http://www.diyaudio.com/forums/solid-state/3075-jlh-10-watt-class-amplifier-33.html#post1480779
http://www.diyaudio.com/forums/solid-state/203431-all-fet-jlh-class.html
All DC coupled.
Cheers,
Patrick
I built the Higher powered version of this about 8 years ago thanks to Geoff Moss (hope he is well).
Spent a heap of money on it with expensive parts like Naked Vishay Z Foil resistors everywhere not sure what it cost me, but no regrets it's a great amp.
Spent a heap of money on it with expensive parts like Naked Vishay Z Foil resistors everywhere not sure what it cost me, but no regrets it's a great amp.
Try the F5, or better still F5X with Toshiba MOSFETs. 🙂
(Something fully complementary ......)
Patrick
(Something fully complementary ......)
Patrick
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There are also such circuits from JLH himself.
The Class-A Amplifier Site - JLH Headphone Amplifiers
(right at the bottom)
http://www.angelfire.com/sd/paulkemble/sound3.html
(also at the bottom)
The key is to find and use truly complementary devices.
Patrick
The Class-A Amplifier Site - JLH Headphone Amplifiers
(right at the bottom)
http://www.angelfire.com/sd/paulkemble/sound3.html
(also at the bottom)
The key is to find and use truly complementary devices.
Patrick
When Bruce wakes up I am sure he will have more than his share of advice here.
Hi Hugh, how are you keeping mate?
Gareth, I was only joking.
Mooly had the right idea, start with the obvious.

Hi Hugh, how are you keeping mate?
Gareth, I was only joking.
Mooly had the right idea, start with the obvious.
Nico,
I'm fine, how about you? We must swap war stories with our health......... groan.......
I am working on new amps consistently, how about you? Business good? I like the JLH amp, I often wonder if it would sound better if we replaced the phase inverter with a CFP.
Cheers,
Hugh
I'm fine, how about you? We must swap war stories with our health......... groan.......
I am working on new amps consistently, how about you? Business good? I like the JLH amp, I often wonder if it would sound better if we replaced the phase inverter with a CFP.
Cheers,
Hugh
Hey abpea, where are you? If you go to Siliconray, he has the boards and some components, and priced right (um, free).
Search results for: 'jlh' - Boards | Kits | Components | Modules | Tools
It even has a free cap multiplier power supply pcb with caps for free too....
I have the kit (PCB with all parts) somewhere downstairs, if I locate you can have it. Where are you? I am in Naperville...
Also follow that Geoff Moss JLH amp link, and ask all questions here. It is a worthwhile build.
Isn't today Sunday? I have just done my churchwork for the week.
Search results for: 'jlh' - Boards | Kits | Components | Modules | Tools
It even has a free cap multiplier power supply pcb with caps for free too....
I have the kit (PCB with all parts) somewhere downstairs, if I locate you can have it. Where are you? I am in Naperville...
Also follow that Geoff Moss JLH amp link, and ask all questions here. It is a worthwhile build.
Isn't today Sunday? I have just done my churchwork for the week.
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Wow, a lot happening here while I slept!!
john65b - I found and ordered silicon rays PC boards. Has anyone else used them? Are they good meaning no errors on the boards? I'm in Champaign, would be happy to meet sometime. 🙂
Mooly, my ignorance appreciates your kindness my friend!!
Nico, I like your suggestion, I'm going to build the 1969 version to see if I can get it done. You know I appreciate the convenience of a PC board but I am really drawn to wiring point-to-point. Something about physically creating the circuit helps me learn more. I'm reading JLH's books and once I have a better understanding of how his circuit works then then I'll no doubt switch to using PC boards for the convenience and speed of putting future amps together. Right now it a challenge for me. It looks like a simple circuit and probably is but for someone learning 'how to do it' I'm finding my arms aren't long enough yet to get around it if you know what I mean. 🙂 I keep saying it and I hope everyone in this forum believes it but I am genuinely and sincerely grateful for everyone's help, advice, patience and kindness. You guys are the best!
On a side note, I have to blame Hugh Dean for all this frustration and thrashing about. I built a pair of Hugh's amp followed by his wonderful preamp a few years ago. I had a great time building the gear and have enjoyed many, many hours listening to music coming out of those amps. Dean was so encouraging and the experience was so pleasurable I just figured it was going to be the same for all my future DIY projects! 🙂
Thanks again -
Bruce
john65b - I found and ordered silicon rays PC boards. Has anyone else used them? Are they good meaning no errors on the boards? I'm in Champaign, would be happy to meet sometime. 🙂
Mooly, my ignorance appreciates your kindness my friend!!
Nico, I like your suggestion, I'm going to build the 1969 version to see if I can get it done. You know I appreciate the convenience of a PC board but I am really drawn to wiring point-to-point. Something about physically creating the circuit helps me learn more. I'm reading JLH's books and once I have a better understanding of how his circuit works then then I'll no doubt switch to using PC boards for the convenience and speed of putting future amps together. Right now it a challenge for me. It looks like a simple circuit and probably is but for someone learning 'how to do it' I'm finding my arms aren't long enough yet to get around it if you know what I mean. 🙂 I keep saying it and I hope everyone in this forum believes it but I am genuinely and sincerely grateful for everyone's help, advice, patience and kindness. You guys are the best!
On a side note, I have to blame Hugh Dean for all this frustration and thrashing about. I built a pair of Hugh's amp followed by his wonderful preamp a few years ago. I had a great time building the gear and have enjoyed many, many hours listening to music coming out of those amps. Dean was so encouraging and the experience was so pleasurable I just figured it was going to be the same for all my future DIY projects! 🙂
Thanks again -
Bruce
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Ha! I was just in Champaign yesterday for the U of I - Western game with my boy! I could have dropped off the PCB and components!
I graduated BSME there in 1987 - are you a student?
After you nail the Amp, your next "project" is a bread-boarded point to point Aikido tubed linestage!!
I graduated BSME there in 1987 - are you a student?
After you nail the Amp, your next "project" is a bread-boarded point to point Aikido tubed linestage!!
A few have suggested the original JLH69 which would be ideal and imo, a better overall design than the later DC coupled ones.
I built both some years ago, and couldn't really pick between them.
I've often fancied having a go at Laurence Nelson-Jones' Class 'A' amp.
http://sound-au.com/tcaas/nj10w.pdf
Well Bruce, what can I say, it is not even Christmas
and the responses are quite overwhelming! 


Before you would consider building again, or buying another power supply, maybe you could test it first with one lab supply.
Only need to add one resistor at the input and one capacitor at the output.
Once it works and you like the results, you would want to build a proper dual-rail power supply anyhow.
Patrick
Thank you Patrick! That's seems easy enough to do I think I'll give it a try and see what happens!
Nico - True words indeed!! 🙂
john65b - Wow, sorry I missed you. Maybe next time you're in town we can get together if you have time. Naperville isn't that far away for me either. 😉 My wife is on the law faculty, I spend my time building audio gear. 🙂
john65b - Wow, sorry I missed you. Maybe next time you're in town we can get together if you have time. Naperville isn't that far away for me either. 😉 My wife is on the law faculty, I spend my time building audio gear. 🙂
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Joined 2009
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I like the JLH amp, I often wonder if it would sound better if we replaced the phase inverter with a CFP.
It requires something special to make it work but I don't know what. I thought you have tried it in some form - when I put it into my JLH69 it robbed the sound of something and I didn't like it.
Nico,
I like the JLH amp, I often wonder if it would sound better if we replaced the phase inverter with a CFP.
Cheers,
Hugh
I sim it with Jfet for input and superpair baxandall for phase inverter. THD is very low.
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