Gentlemen, find attached the current list of reservations.
All of the surplus PCBs are reserved.
I will send the PCBs (shown in my post # 1098) to my German DIY-friend Peter, who owns a circular saw bench with a diamond saw blade and who will cut them into 2 PCBs.
Only when I receive the PCBs back, I will send you the payment information and ...
Best regards - Rudi_Ratlos
All of the surplus PCBs are reserved.
I will send the PCBs (shown in my post # 1098) to my German DIY-friend Peter, who owns a circular saw bench with a diamond saw blade and who will cut them into 2 PCBs.
Only when I receive the PCBs back, I will send you the payment information and ...
Best regards - Rudi_Ratlos
Attachments
Cheers,
my Symasym Black Beauty V1 are running perfectly. Currently still hooked up on my, soon to be replaced by the Line Pre, DCB1 Mezmerize. Sadly I am still missing Gainstage Caps though... Thank you very much for realizing this Rudi, and for all who are still unsure, his PCBs (at least Rev1, but I am sure this also counts for Rev2) are absolutely stunning and a gem to work with.
https://www.dropbox.com/s/3h5m929aelg5jnz/IMAG0259.jpg?dl=0
my Symasym Black Beauty V1 are running perfectly. Currently still hooked up on my, soon to be replaced by the Line Pre, DCB1 Mezmerize. Sadly I am still missing Gainstage Caps though... Thank you very much for realizing this Rudi, and for all who are still unsure, his PCBs (at least Rev1, but I am sure this also counts for Rev2) are absolutely stunning and a gem to work with.
https://www.dropbox.com/s/3h5m929aelg5jnz/IMAG0259.jpg?dl=0
Gentlemen (of post #1107), dear friend Joseph:
I received the PCBs from my German DIY-friend Peter (who cut them) today.
The PCBs look like a gem, and I kept 2 of them for myself to simply put them into my cupboard and take a look at them one day and the other.
If you would like to have a pair them (along with the matching PCB): please transfer 29€ to my PAYPAL-ID: RRozek@t-online.de
Make sure that your EMail-address (as I find it in your PAYPAL-sheet) is correct.
I will then send you the PCBs, the Builder's Manual, drilling template ..., and maybe: I will offer you all that is needed ("hard-to-get components") to do a successful build of this beautiful SYMASYM.
Best regards - Rudi_Ratlos
I received the PCBs from my German DIY-friend Peter (who cut them) today.
The PCBs look like a gem, and I kept 2 of them for myself to simply put them into my cupboard and take a look at them one day and the other.
If you would like to have a pair them (along with the matching PCB): please transfer 29€ to my PAYPAL-ID: RRozek@t-online.de
Make sure that your EMail-address (as I find it in your PAYPAL-sheet) is correct.
I will then send you the PCBs, the Builder's Manual, drilling template ..., and maybe: I will offer you all that is needed ("hard-to-get components") to do a successful build of this beautiful SYMASYM.
Best regards - Rudi_Ratlos
Attachments
I have received an EMail from AndrewT. (whom I appreciate very much) and who is currently evaluating a former revision of my SYMASYM.
Tested power output today.
With 244Vac mains into a 29-0-29Vac 300VA transformer (intended for both channels when I case them).
Maximum outputs are:
29.3Vac open load. The input BC550 (nice choice as well - Rudi) are running at 43.1Vce, a bit high but still below 45Vce, if mains goes to 253Vac.
26.5Vac into 8r0 (87.7W)
24.8Vac into 4r0 (154W)
22.4Vac into 2r0 (254W)
That is with temporary PSU cabling using just 0.6mm hookup wire and no chassis.
OH !! A big plus. The output stays close to zero Volts, if it loses a single rail.
Have fun with the SYMASYM - Rudi_Ratlos
Tested power output today.
With 244Vac mains into a 29-0-29Vac 300VA transformer (intended for both channels when I case them).
Maximum outputs are:
29.3Vac open load. The input BC550 (nice choice as well - Rudi) are running at 43.1Vce, a bit high but still below 45Vce, if mains goes to 253Vac.
26.5Vac into 8r0 (87.7W)
24.8Vac into 4r0 (154W)
22.4Vac into 2r0 (254W)
That is with temporary PSU cabling using just 0.6mm hookup wire and no chassis.
OH !! A big plus. The output stays close to zero Volts, if it loses a single rail.
Have fun with the SYMASYM - Rudi_Ratlos
A follow up on the results shown in post1112.
The 2pair output stage has a cold power capability of 4*150 = 600W @ 25°C The input pair are socketed BC550c and can be changed to other bce, or ecb, or gds (sk170) types.
The 1943/5200 are not a good choice at high supply voltages.
At the +-43Vdc they are a good choice and applying the normal factor of 5, the prediction for maximum output power is 120W.
The amplifier as tested will give 120W into a 5r6 load. i.e. the 2pr 1943/5200 can be rated as a 120W into 5.6ohms amplifier.
It can be used with 6ohms speakers (100W), or with 8ohms speakers (75W).
It cannot be used with 4ohms speakers.
Unless they are substantially resistive (low reactance) AND the heatsink is kept very cool.
The ~6ohms capable amplifier delivers current into 2r0 with a good voltage drive, i.e. the output voltage has not collapsed into a load that draws approximately 3times the rated 6r0 current. This is a good indication that the amplifier is a genuine 6ohms rated amplifier.
at 220Vac or 230Vac the maximum output power will be considerably less, than what I measured when mains was at 244Vac. It will also run cooler, since Pquiescent is less.
For those that are looking and wondering 29-0-29Vac !
It started as an RS supplied 300VA 230:0-25+0-25Vac which becomes ~26Vac @ 240Vac. I added two windings with 13turns each to make an extra 3Vac, to give the final 240:0-29+0-29Vac converted to centre tapped at the PSU.
I have not attempted to measure it, but I guess the final assembly to be approximately 330VA.
Two channels of 87W into 8ohms, comes to a total maximum power of 174W, the VA/MaxP = ~1.9 (inside that 1 to 2times I regularly state as a guide.)
The 2pair output stage has a cold power capability of 4*150 = 600W @ 25°C The input pair are socketed BC550c and can be changed to other bce, or ecb, or gds (sk170) types.
The 1943/5200 are not a good choice at high supply voltages.
At the +-43Vdc they are a good choice and applying the normal factor of 5, the prediction for maximum output power is 120W.
The amplifier as tested will give 120W into a 5r6 load. i.e. the 2pr 1943/5200 can be rated as a 120W into 5.6ohms amplifier.
It can be used with 6ohms speakers (100W), or with 8ohms speakers (75W).
It cannot be used with 4ohms speakers.
Unless they are substantially resistive (low reactance) AND the heatsink is kept very cool.
The ~6ohms capable amplifier delivers current into 2r0 with a good voltage drive, i.e. the output voltage has not collapsed into a load that draws approximately 3times the rated 6r0 current. This is a good indication that the amplifier is a genuine 6ohms rated amplifier.
at 220Vac or 230Vac the maximum output power will be considerably less, than what I measured when mains was at 244Vac. It will also run cooler, since Pquiescent is less.
For those that are looking and wondering 29-0-29Vac !
It started as an RS supplied 300VA 230:0-25+0-25Vac which becomes ~26Vac @ 240Vac. I added two windings with 13turns each to make an extra 3Vac, to give the final 240:0-29+0-29Vac converted to centre tapped at the PSU.
I have not attempted to measure it, but I guess the final assembly to be approximately 330VA.
Two channels of 87W into 8ohms, comes to a total maximum power of 174W, the VA/MaxP = ~1.9 (inside that 1 to 2times I regularly state as a guide.)
Last edited:
Rick, I do not recommend use the Toshiba 2SA1943 / 2C5200.
When the SYMASYM has been originally presented in this thread: http://www.diyaudio.com/forums/soli...ifier-designed-michael-bittner-our-mikeb.html
Pavel Macura experienced the SYMASYM to oscillate on its ouput, when he used the TOSHIBA output transistors.
He has been able to correct this error by using a different value for the NFB compensation capacitor.
The SYMASYM has been successfully tested with all kinds of OnSemi output transistors: MJL3281/MJL1302, MJL4281/MJL4302, MJW0281/MJW0302, NJW0281/NJW0302, MJL21194/MJL21193, ...
I am currently testing the SANKEN 2SC3263/2SA1294.
@Evette, Atupi, Potepuh, Arthur, IPolyakov: thank you for you money transfer.
I will send you the Builder's Manual, drill template, BoM, .... to your EMail adresses this weekend.
Best regards - Rudi
When the SYMASYM has been originally presented in this thread: http://www.diyaudio.com/forums/soli...ifier-designed-michael-bittner-our-mikeb.html
Pavel Macura experienced the SYMASYM to oscillate on its ouput, when he used the TOSHIBA output transistors.
He has been able to correct this error by using a different value for the NFB compensation capacitor.
The SYMASYM has been successfully tested with all kinds of OnSemi output transistors: MJL3281/MJL1302, MJL4281/MJL4302, MJW0281/MJW0302, NJW0281/NJW0302, MJL21194/MJL21193, ...
I am currently testing the SANKEN 2SC3263/2SA1294.
@Evette, Atupi, Potepuh, Arthur, IPolyakov: thank you for you money transfer.
I will send you the Builder's Manual, drill template, BoM, .... to your EMail adresses this weekend.
Best regards - Rudi