I don't, but perhaps you might want to specify which amp you are interested in, the original, or Juma's latest version.
Trust Juma to come up with something better! (He is also the master of understatement...salutes to him!)
Perhaps a few more tips and guidance from the master would make our journey forward easier...
Personally I feel this is a good candidate for P2P realization.
Stay home, stay safe...with good music!
Perhaps a few more tips and guidance from the master would make our journey forward easier...
Personally I feel this is a good candidate for P2P realization.
Stay home, stay safe...with good music!
@ Juma
Sir Juma, would you advise replacing Iq setting control P2 with a suitable LED (or two, with a shorting jumper across, for high/low bias setting) in the original version?
Your guidance is awaited.
Thanks and warm regards.
Sir Juma, would you advise replacing Iq setting control P2 with a suitable LED (or two, with a shorting jumper across, for high/low bias setting) in the original version?
Your guidance is awaited.
Thanks and warm regards.
Sure, why not?
Blue for about 0.7A, two reds for a bit less or two greens for a bit more or any combination of those (including simple diodes like 1n4148) - some experimenting is needed (not all Laterals are perfectly equal) so do some testing, there's no harm in it...
Regards
🙂
Blue for about 0.7A, two reds for a bit less or two greens for a bit more or any combination of those (including simple diodes like 1n4148) - some experimenting is needed (not all Laterals are perfectly equal) so do some testing, there's no harm in it...
Regards
🙂
@ Juma
Sir Juma, thank you so much for the prompt guidance regarding the original version. 🙂
Perhaps you will allow me to bring up a few points re. the new JFET input version presented in Post # 180.
I had seen a similar 'positive ground' approach long back while trying out a Power Follower by Andrea Ciuffoli -- which I had thought sounded better than the "standard version" with a negative ground.
( http://www.audiodesignguide.com/my/Follower_99c.gif )
May I request you to go into some detail regarding the advantages of this topology and why you chose to opt for this approach, surely in the interests of better sound. (Mr Ciuffoli speaks of the decoupling of the signal currents from the power supply etc, which goes above my head.)
I hope you would also suggest some more easily available JFET input devices that could be tried by hobbyists.
I have always been amused by the "no capacitors in the signal path" brigade (though I am no qualified engineer), for the simple reason what exotica they were using in their power supplies.
With this thought in mind, I would like to tap your wisdom about replacing the speaker coupling capacitor with a pair of electrolytics in series across the power supply, and returning the speaker 'ground' to the mid-point of those.
Hobbyists are not commercial designers tasked with saving every penny!
Warm regards, as always.
Sir Juma, thank you so much for the prompt guidance regarding the original version. 🙂
Perhaps you will allow me to bring up a few points re. the new JFET input version presented in Post # 180.
I had seen a similar 'positive ground' approach long back while trying out a Power Follower by Andrea Ciuffoli -- which I had thought sounded better than the "standard version" with a negative ground.
( http://www.audiodesignguide.com/my/Follower_99c.gif )
May I request you to go into some detail regarding the advantages of this topology and why you chose to opt for this approach, surely in the interests of better sound. (Mr Ciuffoli speaks of the decoupling of the signal currents from the power supply etc, which goes above my head.)
I hope you would also suggest some more easily available JFET input devices that could be tried by hobbyists.
I have always been amused by the "no capacitors in the signal path" brigade (though I am no qualified engineer), for the simple reason what exotica they were using in their power supplies.
With this thought in mind, I would like to tap your wisdom about replacing the speaker coupling capacitor with a pair of electrolytics in series across the power supply, and returning the speaker 'ground' to the mid-point of those.
Hobbyists are not commercial designers tasked with saving every penny!
Warm regards, as always.
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@ Juma
Sir, many (like me!) would like to try your original design with the 'positive ground' topology, with its advantages. And quite a few would be in a position where a side-by-side comparison could be made easily.
Kindly guide with a re-drawn circuit.
Thanks and regards.
Sir, many (like me!) would like to try your original design with the 'positive ground' topology, with its advantages. And quite a few would be in a position where a side-by-side comparison could be made easily.
Kindly guide with a re-drawn circuit.
Thanks and regards.
@ Juma
My fault--I had thought perhaps you had some free time during the Covid lockdown and all that (which was a Godsend to finish old projects and try something new also!).
Though I am a bit dispirited, I earnestly hope you would devote some time to my requests as soon as you could find some free time.
Warm regards.
My fault--I had thought perhaps you had some free time during the Covid lockdown and all that (which was a Godsend to finish old projects and try something new also!).
Though I am a bit dispirited, I earnestly hope you would devote some time to my requests as soon as you could find some free time.
Warm regards.
Hi, everybody!
May I use the 40V AC secondaries and the Cap Multiplier used for the original circuit in this second Version - of course with the polarities changed to match the circuit? The circuit voltage will be around 48-50V so I think the J310 will be used to it's limits but it will survive, the R12 - 1K/1W could be replaced with 1K2 but need confirmation and the other changes to the components, please, if needed.
I cannot take out some wires from my Toroidal Transformer to get the 40V DC needed for the circuit because of it's center filled with epoxy.
Thanks in advance for your advice!
May I use the 40V AC secondaries and the Cap Multiplier used for the original circuit in this second Version - of course with the polarities changed to match the circuit? The circuit voltage will be around 48-50V so I think the J310 will be used to it's limits but it will survive, the R12 - 1K/1W could be replaced with 1K2 but need confirmation and the other changes to the components, please, if needed.
I cannot take out some wires from my Toroidal Transformer to get the 40V DC needed for the circuit because of it's center filled with epoxy.
Thanks in advance for your advice!