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PaX amplifier: invitation to discussion

HiFi, LoFi, Tubes, Transistors, ICs, Commercial, DIY

Re: PaX amplifier: invitation to discussion

Postby Ravindra » Fri Sep 19, 2014 7:52 am

Dear Mr. Didden,

Thank you for the wonderful implementation of error correction topology in your paX amplifier design.
The Output Current Stage (Cos), described in part-1 of the article on paX, achieves an error corrected unity gain current amplifier, while the Voltage amplification stage (Vas), described in part-2 of the article on paX, achieves an error corrected gain of 20.

The two separately designed Output Current Stage (Cos) and the Voltage amplification stage (Vas) helps everyone understand the novel use of the 'current conveyor.'
However, I was wondering if it is possible to modify the Vas to completely eliminate the current amplifier stage. That will get rid of a lot of hardware. My thoughts may be biased by long exposure to negative feedback topologies which makes me see that the Vas is designed in a very generic way. So kindly bear with me.

Also, while the error correction topology works at minimizing the distortion, the current dumping topology does that and also eliminates the tedious task of setting the bias current and other thermal stability. I am eager to know that besides elimination of crossover distortion, does the Class-A/Class-AB stages used in current dumping also offer better thermal efficiency.

Do you think it is worth re-visiting the Current Dumping Amplifier with new devices if it has more/better advantages?

You have vast experience, access to elaborate equipments and labs. Could I have your views on the the two topologies compared side by side? Is there any possibility that a hybrid of the two be possible? If you have already compared/ heard the two topologies, which I am sure you have, can you share any insights with us here?

I eagerly look forward to your reply.

Thanks and regards,

Posts: 6
Joined: Thu Sep 18, 2014 3:21 pm


Postby al2002 » Fri Dec 25, 2015 6:01 am

janneman01 wrote:OK, I checked the changes necessary to run the paX amp at +/-30VDC for 40-50W output power. There are several resistor value changes and two zener value changes. I added a page to my website with the details, here: Let me know if you can work with that, and how it goes. Best, Jan Didden

Hello Jan,

I know it is 7 years later, but the link"" does not work. Can you send correct link?

Thanks in advance,
Posts: 1
Joined: Fri Dec 25, 2015 5:55 am

Re: PaX amplifier: invitation to discussion

Postby hadihf » Sat Jan 13, 2018 12:59 pm

Finally finished Jan's error correction amplifier. Jan has been a great help. Very pleased with the sound. Center of my music system from now on.

Best Regards
paX Front.jpg
Posts: 49
Joined: Thu Jan 02, 2014 10:37 am


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