Gentlemen, I just returned from the local post-office.
The letters are on their way to you.
When you open the letters, please keep in mind the emitter resistors as well.
The small enevelope with them might have slipped into a corner of the letter.
If you have any questions regarding your build: where to get components, which components to use, different resistor values in case you use a pre-amplifier,
how to adjust, ...., and are not able to translate th German Builder's Manual that I have sent you, ask your question here.
I wish you a successful build and happiness, when you listen to the sound of the SYMASYM finally.
Best regards - Rudi_Ratlos
The letters are on their way to you.
When you open the letters, please keep in mind the emitter resistors as well.
The small enevelope with them might have slipped into a corner of the letter.
If you have any questions regarding your build: where to get components, which components to use, different resistor values in case you use a pre-amplifier,
how to adjust, ...., and are not able to translate th German Builder's Manual that I have sent you, ask your question here.
I wish you a successful build and happiness, when you listen to the sound of the SYMASYM finally.
Best regards - Rudi_Ratlos
Carl,
I have already begun to solder my own TO-264 / TO-3P SYMASYM.
I will user NJW0281/NJW0302 as OP-transistors.
I have wound 2 PI-filters (33 Ohm / 1µH) for the PSU, have wound a PI-/EMI - filter (10Ohm / 1µH) for the speaker output, ...,
but I ran out of resistors!
I will take my bicycle and drive to Hamburg right now and buy a couple of 1R2 and 22K resistors.
You have to be patient for some days yet.
The PCBs are on their way to you.
Best reagrds - Rudi_Ratlos
I have already begun to solder my own TO-264 / TO-3P SYMASYM.
I will user NJW0281/NJW0302 as OP-transistors.
I have wound 2 PI-filters (33 Ohm / 1µH) for the PSU, have wound a PI-/EMI - filter (10Ohm / 1µH) for the speaker output, ...,
but I ran out of resistors!
I will take my bicycle and drive to Hamburg right now and buy a couple of 1R2 and 22K resistors.
You have to be patient for some days yet.
The PCBs are on their way to you.
Best reagrds - Rudi_Ratlos
Attachments
Here you go...
It is very simple PSU but has capability of being a regulator with different components. In this case it is a simple CRC filter - and the rectifiers are off-board with this PCB.
I am using 4XPanasonic 0.47R per rail. Caps are 50V.\
These are the rectifiers Supposedly the Pass amps use this or something very similar. I have used them in many amps and they seem to work good and are very reasonable.
It is very simple PSU but has capability of being a regulator with different components. In this case it is a simple CRC filter - and the rectifiers are off-board with this PCB.
I am using 4XPanasonic 0.47R per rail. Caps are 50V.\
These are the rectifiers Supposedly the Pass amps use this or something very similar. I have used them in many amps and they seem to work good and are very reasonable.
Attachments
Last edited:
Thank you for the picture, Carl.
This PSU is indeed very versatile and will do a good job for the SYMASYM.
The heatsinks of your case are more than sufficient. Be sure to apply a thin film of thermal grease between the ALU-L profiles and the heatsinks.
May be, there already is - at least on the right side.
Tell me: which transformer will you use?
The ratings of the SYMASYM are: 100W @ 4 Ohm and 60Watt @ 8 Ohm using a transformer with 2 x 27 VAC secondaries / 225W.
If you want to go for higher ratings (f.e. by using a 2 x 30 VAC / 300W transformer): be sure to insert an appropriate ZENER diode
into the onboard-CAP-multiplier to prevent damage to your input transistors (2SK170 f.e.).
Best regards - Rudi_Ratlos
This PSU is indeed very versatile and will do a good job for the SYMASYM.
The heatsinks of your case are more than sufficient. Be sure to apply a thin film of thermal grease between the ALU-L profiles and the heatsinks.
May be, there already is - at least on the right side.
Tell me: which transformer will you use?
The ratings of the SYMASYM are: 100W @ 4 Ohm and 60Watt @ 8 Ohm using a transformer with 2 x 27 VAC secondaries / 225W.
If you want to go for higher ratings (f.e. by using a 2 x 30 VAC / 300W transformer): be sure to insert an appropriate ZENER diode
into the onboard-CAP-multiplier to prevent damage to your input transistors (2SK170 f.e.).
Best regards - Rudi_Ratlos
I am starting out with an Antek 300VA dual 25V secondary unit.
Yes I had applied thermal grease to the L profiles, I just hope they are large enough to accommodate the board, they are about 25mmX25mm. I know the TO-3P will fit easily, just if the board provides enough clearance. Might have to get creative when bending the leads for the transistors.
Yes I had applied thermal grease to the L profiles, I just hope they are large enough to accommodate the board, they are about 25mmX25mm. I know the TO-3P will fit easily, just if the board provides enough clearance. Might have to get creative when bending the leads for the transistors.
OK,
Got the 1.5" L profiles cut and ready to go...just need to drill and tap the holes for the transistors.
Can you confirm the width of the board? I saw 100mm for the TO-3 version, is this board the same size width?
It will be tight but I think everything will fit.
Got the 1.5" L profiles cut and ready to go...just need to drill and tap the holes for the transistors.
Can you confirm the width of the board? I saw 100mm for the TO-3 version, is this board the same size width?
It will be tight but I think everything will fit.
Attachments
As long as they clear the toroid!!! LOL
I cut the l profiles a little long so I have some flexibility.
Thank you, Tom.
Carl: warm up solder iron!
If you have any questions concerning your build, for example: how to adjust, use of the onboard CAP-multiplier, differences in using the SYMASYM
with or without pre-amplifier, ...: do not hesitate and post your questions here!
I have already begun with my (my brother's) build!
Best regards - Rudi_Ratlos
P.S. There is still 1 SYMASYM - set (see post #483) left!
Carl: warm up solder iron!
If you have any questions concerning your build, for example: how to adjust, use of the onboard CAP-multiplier, differences in using the SYMASYM
with or without pre-amplifier, ...: do not hesitate and post your questions here!
I have already begun with my (my brother's) build!
Best regards - Rudi_Ratlos
P.S. There is still 1 SYMASYM - set (see post #483) left!
Attachments
Last edited:
Sir Rudi,
What should be the value of the zener diode if I use 2 x 30 VAC / 300W ?
regards,
Marjohn