Explendid amplifier designed by Michael Bittner, our MikeB

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My SymAsym 5_3

After a year-long break, here it is! Complete with remote-control-relay-based R2R attenuator and source selector, soft-start, speaker delay and DC&thermal protection, all encased in nice case!
It sounds as it should and all that's missing is a proper front panel instead of this one that I made from cardboard 😀 ... I have the thick, black Aluminum one that came with the case but I still need to find a place where to machine it properly.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.


Edit: I hope the image thumbnails do not appear so large as to require a horizontal scroll. If they do... it means I need help 😀
 
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i have read that the amp has some istability issues when used with 2sc5200-2sa1943. when i did a simulation i found that these do not give a very good phase and gain margin .a more appropriiate output would be mjl21193 mjl21194 and 10p feedback capacitor.what is your opinion about these because i already have built two channels but i dont know what output transistors to put.
 
I was thinking of using the PCB set from tubeshunter on ebay to build the symasym 5.3 amp:

symasym items - Get great deals on Electronics, goldmund items on eBay.com!

Has anyone tried these boards? Only difference I can see so far is the multi-turn pot for R22. For R27 and R28 (0.22 ohm 5 watt), do you recommend metal oxide or wire wound? This would be my first amp build so might be diving in the deep end. But all the positive reviews I have read about it so far has me wanting to give it a go.

Thanks,
Philippe
 
There is a beautiful PCB of the SYMASYM, being offered in a group-buy of the German AAA-forum.

An externally hosted image should be here but it was not working when we last tested it.


The picture above shows one channel of my SYMASYM.

This group-buy is authorized by Michael Bittner.

If somebody likes to have this PCB: write me a PM please and I will ask the German "Group-buy Thread" owner for some PCBs.

Best regards - Rudi_Ratlos