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TO-3 SYMASYM

Dear Rudi,

Very nice concept. Its like a potter with clay you just get better and better and better. Yes there is just a way that that design describes it self.

About the PS there was a concept I was describing once in the PS thread.
301273d1347600621-power-supply-resevoir-size-parallel-caps.png


321310d1357241575-power-supply-resevoir-size-ps2_sample.png

I also remember a member encountered some issues with the on-board large bang bang caps including you, however that time they were placed near the low noise circuits. This time somethings a different will follow the thread on results.

kind regards,

Harrison.

Loek: the 22R resistors around the input are only used, if you operate the SYMASYM from an "active PreAmplifier (Gain >0)" .
In case you use a passive PreAmplifier (Source Selection + potentiometer), the 22R resistors are replaced by wires (will be bridged).

Best regards - Rudi_Ratlos

P.S.: In the meanwhile I have the enhanced (?) the on-top reservoir-capacitor layout by a new one, since I have had some luck and "inherited" a couple of "ELNA for AUDIO caps" for a very nice offering.
I wonder, how the NJW0 transistors will sound as compared to the TO3.

Best regards - Rudi_Ratlos
 
Harrison, thank you for you recommendation.
A German DIY-friend of mine told me exactly the same, so my efforts ended up in the attached layout: 1µF MKT || 2 x 2.200µF || 15.000µF .

I will then evaluate the differences in sound,

- when I operate this SYMASYM from a standard PSU
- when I operate it from a SMPS (SMPS300RE, +/-36VDC, 300VA)
- when I operate it from a rectifier section only

Best regards - Rudi_Ratlos

P.S.: Loek: the output- transistors are mounted underneath the PCB. So there is no clearance-problem with the 22R resistors.
 

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Hi Rudi,
you are faster than me (after our mail's I'm also working on it,
but first need to finish my F5).
During some minutes on the layout I was thinking to give every
transistor it's own capacitor... my meaning is of course the capacitor's
are connected to eachother, but shortest way direct to transistor and
0.1Ohm to connect them to eachother.
Hope my explaining is understandable....
best regards huggy
 
Member
Joined 2004
Paid Member
My new SymAsym TO3

Hi

I have my new SymAsym TO3 running, and I am very happy to report that having connected the amp to speakers and powered it on, there is (without input) no hum, no hiss, no noise at all, it is dead quiet. When some nice input music is given to it, the output gives sweet sound, very pleasing : it is a great amp and I did not think that a diyaudio amp could be that great sounding !

Thank you for sharing your work with all of us Rudi ! I am so happy to have had the good idea to build it using your wonderful PCBs and your Builder's Manual that has been written fool proof, all questions one could have building it are answered ! I did not think that a diy power amp could be that good !

Thank you Rudi ! I am so happy with your SymAsym TO3 !

Here is my build in the chassis.

Best regards

rephil
 

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Member
Joined 2004
Paid Member
Very nice build indeed
The TO3 holes in the bracket did they fit well?

Yes they fit perfectly :D, but I will not tell you how many L-brackets I did use for the learning pourpose in order to get the experience for having this result ;). The result at the end did come : I am able to repeat that good result when I want it :). Now I have the knowledge :cool:.

Best regards

rephil
 
Member
Joined 2004
Paid Member
Yes you really need to prep the surface of the L brackets so there are NO sharp surfaces above the plane of the holes. I use 120grit and a palm sander.

Hi cjkpkg,

Yes, it must be done like that, and so did Rudi write in his Builder's Manual. So did I do too ... SymAsym TO3 from Rudi is a great amp :D that I did build ! It is difficult to buy and to get that quality from an industrial amp, I mean not paying so much that you don't want to go back home :eek: because your wife is waiting :mad: for you and will ask you to explain "that much money gone for nothing useful, this when she needs so many useful things that you did not buy and that she must do without ...;) ". SymAsym TO3 IS the solution to that bad life !

Best regards

rephil
 
Hi cjkpkg,

Yes, it must be done like that, and so did Rudi write in his Builder's Manual. So did I do too ... SymAsym TO3 from Rudi is a great amp :D that I did build ! It is difficult to buy and to get that quality from an industrial amp, I mean not paying so much that you don't want to go back home :eek: because your wife is waiting :mad: for you and will ask you to explain "that much money gone for nothing useful, this when she needs so many useful things that you did not buy and that she must do without ...;) ". SymAsym TO3 IS the solution to that bad life !

Best regards

rephil

Excellent summary of our little passion here...
 
Randy, I have never before used the big SANKEN transistors in any of my SYMASYM layouts.
But I did, when I built one of DESTROYERX' DX - amplifiers several years ago, and the SANKEN sounded really well. "They rocked".

I will no more offer the TO3-version of the SYMASYM. I did a new layout using NJW0281 / NJW0302 that need to be mounted beneath the PCB.

Best regards - Rudi_Ratlos
 

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Gentlemen, I feel very happy and will offer you some (at most 12) PCBs of my current layout of the "R-SYM":



http://abload.de/img/r-sym005yckvk.jpg

The current layout is using NWJ0281 / NJW0302 transistors that have to be mounted beneath the PCB.
The size of the PCB is 140 x 80 mm.
The heatsinks that I am showing come from TME.EU and cost about 6€ per piece.

2 PCBs incl. worldwide shipping will cost 20€.

If somebody is interested in these PCBs: please tell me.

Best regards - Rudi_Ratlos

P.S.: Do I need to say that this SYMASYM is one of the best- sounding, low-priced - amplifiers being offered in this forum?
 
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