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Ultra high spec. opamp MC/MM phono, warp "elliptic" filter, line, headphone amps.

Wyn Palmer Amplifier Development Thread

Wyn is once again donating his design services! This time for a power amp. (target specs can be seen in this post: https://audiokarma.org/forums/index.php?threads/wyn-palmer-amplifier-development-thread.1081840/#post-17684419) After the success of the phono preamplifier, this should prove to be...
audiokarma.org

Link to amplifier thread. Let me know if you'd like me to edit anything before the edit window closes on me...

EDIT- corrected typos over there... (eyeroll)
 
j!m said:

Wyn Palmer Amplifier Development Thread

Wyn is once again donating his design services! This time for a power amp. (target specs can be seen in this post: https://audiokarma.org/forums/index.php?threads/wyn-palmer-amplifier-development-thread.1081840/#post-17684419) After the success of the phono preamplifier, this should prove to be...
audiokarma.org

Link to amplifier thread. Let me know if you'd like me to edit anything before the edit window closes on me...

EDIT- corrected typos over there... (eyeroll)
Click to expand...
I had the mods move it to the DIY forum Jim ;) .

Nashou
 
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The first schematic and simulation results for the PA is up.

Wyn Palmer Amplifier Development Thread

Wyn is once again donating his design services! This time for a power amp. (target specs can be seen in this post: https://audiokarma.org/forums/index.php?threads/wyn-palmer-amplifier-development-thread.1081840/#post-17684419) After the success of the phono preamplifier, this should prove to be...
audiokarma.org
I've revised the posts a couple of times, and the work is ongoing, but it's a start for anyone that might be interested.
 
wyn palmer said:
The first schematic and simulation results for the PA is up.

Wyn Palmer Amplifier Development Thread

Wyn is once again donating his design services! This time for a power amp. (target specs can be seen in this post: https://audiokarma.org/forums/index.php?threads/wyn-palmer-amplifier-development-thread.1081840/#post-17684419) After the success of the phono preamplifier, this should prove to be...
audiokarma.org
I've revised the posts a couple of times, and the work is ongoing, but it's a start for anyone that might be interested.
Click to expand...
If you're ready for 1st layout please send me schematic.
 
hirscwi said:
If you're ready for 1st layout please send me schematic.
Click to expand...
I'm still considering the power supply and thermal requirements, and whether it really is feasible to build the design as modules.
I've completed the frequency response, stability (as far as I can tell) and component miss-match issues evaluation, and I've added a simple power on mute timer which differs from the datasheet version. I've also looked at the LF power supply rejection independent of the decoupling networks.
I don't have a particular schedule for completing the remainder of the tasks, but they are ongoing.
 
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I've completed the non power supply design.
hirscwi said:
No need to be in any rush. Take time and enjoy it.
Click to expand...
I suggest that you read what Tom Christiansen has to say before you embark on a layout as it will be very helpful.
neurochrome.com

Taming the LM3886 Chip Amplifier | Neurochrome

Get the best performance from the LM3886 chipamp kits. Learn power supply design; thermal design; stability; snubbers, rectification, and decoupling; PCB layout, and more.
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The present design embodies all that he recommends for the basic approach, except the power supply, which I hope to finalize in the next few days.
The local opamp decoupling is now done. I'll post details tomorrow.
The power supply will be separate, so the addition of the decoupling will be sufficient to start a main board layout.
I would suggest two identical boards, even though one will not require the input buffers. The buffer outputs can be routed back to the board edge then wired to the appropriate differential to single ended converter inputs.
 
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OK I'll shift to that thread. It sounds like it's time for layout of the amp section. I'd like to finish the transimpedance prototype first though.
 
hirscwi said:
OK I'll shift to that thread. It sounds like it's time for layout of the amp section. I'd like to finish the transimpedance prototype first though.
Click to expand...
I'm in no hurry. I'm doing this to satisfy a request from @mkane etc. How much of a hurry are they in?
Other than that, it's provided several hours of entertainment- which is always welcome.
Incidentally, there's some activity on DiyAudio concerning the v4 design. It's a bit of a drive by shooting, if you know what I mean, but I'm trying to extract the maximum amount of intelligent interaction that I can from it. It also may provide some further insight into some of the V4 design choices, for those who are interested.

Ultra high spec opamp MC/MM phono, warp "elliptic" filter, line, headphone amps

I agree with the former, but not sure how one makes gerbers available only to close groups of people yet still distribute them. Can you elaborate? The gerbers would be published to everyone. If a few friend in close locale order, they can save a bit on shipping. Nothing more complicated than...
www.diyaudio.com www.diyaudio.com

By the way I find posting on DIY Audio really annoying. They leave some miniscule time for editing posts and as I post en passant in most cases but have found that saving is necessary to avoid losing what I have "written" it makes it much harder than AK.
I still haven't decided if posting the PA on DiyAudio is worthwhile. I think that I've employed what intelligence is available from the web.
Any opinions, now that a "final" schematic is available?
 
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Hey Wyn, I saw it posted at some point that the original board gerbers had c50 screened backwards. Unfortunately, the schematic is too blurry for me to read, and I'm trying to determine if it's backwards on my boards.

Do you have a higher resolution schematic?

Thanks!
 
scootsity5 said:
Hey Wyn, I saw it posted at some point that the original board gerbers had c50 screened backwards. Unfortunately, the schematic is too blurry for me to read, and I'm trying to determine if it's backwards on my boards.

Do you have a higher resolution schematic?

Thanks!
Click to expand...
Just touch an ohmmeter from the PCB cap holes to ground - one of the two holes will show a short to ground - that's where your negative lead goes.
Also there's good resolution schematics on the build thread, you just have to zoom in.
Mike
 
mikebarney said:
Just touch an ohmmeter from the PCB cap holes to ground - one of the two holes will show a short to ground - that's where your negative lead goes.
Also there's good resolution schematics on the build thread, you just have to zoom in.
Mike
Click to expand...
I'll check that thread. Thanks!
 
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