No-global-loop amplification

Following Pavel's post, I have tested the concept with diamond IPS.


Valery, thank you for checking an idea.
Very good results!

The cascodes noticeably reduce 2-nd harmonic, improving overall performance, with 3-rd harmonic dominance. This configuration also shows rather good result in terms of IMD.


Cascoded one needs a cascoded current source for keeping overall concept and idea!
;)

Something like this:
IMG_6548.JPG

With high enough caps it will also provide nice soft-start with intrinsic noise filtering.
 
Diamondstark PA1

OK, here is my simulation with OPS, utilizing one of the known local error correction techniques. Most of the distortion is coming from OPS anyway, however it looks pretty good even close to clipping (100W @ 8 ohm).

I will simulate a few other OPS options and then - live testing will show if the thing is worth all the work done so far :rolleyes:
 

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Simplestark

Finally - not as sophisticated and accurate as the previous one, but a rather simple one and still promising in terms of the way it's going to sound.

Self-biasing IPS, trimmers for OPS offset and bias settings.
 

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Just a little help with PCB . I hope no errors . Maybe someone want to try ....:)

Hi Alex, thanks a lot for this piece of art - great work, as usual :up:

Would you mind to share the gerbers or whatever interchange format, suitable for ordering the boards (this one will go for no-profit DIY purposes only)?
My building abilities are temporary limited, but I will find the way to prototype and test this one :cool:

Cheers,
Valery
 
Valery,

I really like your amp, and now that Alex MM has done a Tintoretto on your Simplestark, it could become a masterpiece, like the JLH........
Mind you, 12 semis, but very innovative and very good figures for a ZFB amp!

Поздравляем с прибавлением!

Hugh

Hi Hugh,

Thank you, good to see you here.
Yes - a great gift from Alex, inspiring for moving the project forward :)

Highly linear ZFB solutions attract my interest - I believe, it's always better to avoid "errors" wherever possible, in the first hand, than to correct them afterwards, one way or the other.

Looking forward to building a prototype - let's see the live performance ;)

Cheers,
Valery
 
Hi Alex, thanks a lot for this piece of art - great work, as usual :up:

Would you mind to share the gerbers or whatever interchange format, suitable for ordering the boards (this one will go for no-profit DIY purposes only)?
My building abilities are temporary limited, but I will find the way to prototype and test this one :cool:

Cheers,
Valery
Pdf or jpg also appreciated;)
 
Files in .pdf format attached :) .I use .rar format and forum not allowed to use it. Gerbers will be send by email . :eek:

Regards,
Alex
 

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  • SIMPLESTARK PCB BOTTOM MIRRORED.pdf
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  • SIMPLESTARK PCB TOP SILSCREEN MIRRORED.pdf
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  • SIMPLESTARK SCHEMATIC.pdf
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