This might me a good isolation solution, as it decouple completely the source from the amp !
Mike, I'll test the Symasym using MPSA18, to see if I have the same "problem" again. I'm almost sure that this started to happen AFTER swap the MPSAs to 2N5551. Furthermore, the amp works perfect, as I already said.
Best Regards !
Mike, I'll test the Symasym using MPSA18, to see if I have the same "problem" again. I'm almost sure that this started to happen AFTER swap the MPSAs to 2N5551. Furthermore, the amp works perfect, as I already said.
Best Regards !
Symassym has not problems.... some folks has bad luck..ahahahha
Você é uma gracinha.
You are very nice.... badlucky
regards,
Carlos
Você é uma gracinha.
You are very nice.... badlucky
regards,
Carlos
Mike,
I replaced the 2N5551 back with the MPSA18, and I still have this happening, despite the perfect work of the amp. I'm suspecting about a faultly capacitor (larger?). Which capacitor may cause this? I can see the woofer moving, but it sounds very soft and not loud. DC offset is 10mV.
Carlos, don't waste your time bothering me 😉 And you can't imagine how lucky I am, as I'm a really happy person and I have everything that I want. Aren't you? Hummm, to be so annoyed with an amplifier thread you don't appear to be, sorry. I really wish to you a lot of happyness!
I'll not answer you anymore untill you say something that can help me with my amp.
I replaced the 2N5551 back with the MPSA18, and I still have this happening, despite the perfect work of the amp. I'm suspecting about a faultly capacitor (larger?). Which capacitor may cause this? I can see the woofer moving, but it sounds very soft and not loud. DC offset is 10mV.
Carlos, don't waste your time bothering me 😉 And you can't imagine how lucky I am, as I'm a really happy person and I have everything that I want. Aren't you? Hummm, to be so annoyed with an amplifier thread you don't appear to be, sorry. I really wish to you a lot of happyness!
I'll not answer you anymore untill you say something that can help me with my amp.Hi Mike.
I am starting make syamssym5_3 with PMA components value, 2SA5200 and and 2SC1943 output. But some components I can't get.
1.Can I change the 0,15 ohm final output emitor resistor
with 0,22 ohm?
2.Can I change BC547C with 2sC1845?
3.Can I change the feedback electrolit cap 470u with bipolar electrlit cap 100u?
4.I like to build input buffer (just like PMA audio buffer but i dont have BUF 634), so what should i do? do u guys have any schematic?
Thank you Gentlemen.
I am starting make syamssym5_3 with PMA components value, 2SA5200 and and 2SC1943 output. But some components I can't get.
1.Can I change the 0,15 ohm final output emitor resistor
with 0,22 ohm?
2.Can I change BC547C with 2sC1845?
3.Can I change the feedback electrolit cap 470u with bipolar electrlit cap 100u?
4.I like to build input buffer (just like PMA audio buffer but i dont have BUF 634), so what should i do? do u guys have any schematic?
Thank you Gentlemen.
Hello
Emitters resistors are calculated. I don't think to change them are a good idea. I'm not sure but you'll may losse a part of ouptut signal.
BC547C are still available from direct order from Mouser or Fairchild.
Feedback cap are calculated for a precise crossover. MikeB or PMA are more able to say if the change will be good or not.
BUF634 are available.
See ya dude,
Max
Emitters resistors are calculated. I don't think to change them are a good idea. I'm not sure but you'll may losse a part of ouptut signal.
BC547C are still available from direct order from Mouser or Fairchild.
Feedback cap are calculated for a precise crossover. MikeB or PMA are more able to say if the change will be good or not.
BUF634 are available.
See ya dude,
Max
The only advantage is in H2 reduction. It will be hard to make it stable without LTP or/and VAS-LTP degeneration.
My 2 cents ...
My 2 cents ...
Based only on simulation, it reduces dramatically both 2nd and 3rd. It reduces higher order as well.
Yes, stability will be a problem, it has tremendous and wideband loopgain (over 80dB!). Cascoding makes sense only in combination with buffering, otherwise it is just to please eye.
Yes, stability will be a problem, it has tremendous and wideband loopgain (over 80dB!). Cascoding makes sense only in combination with buffering, otherwise it is just to please eye.
Hi,
Cascoding allows you to run cooler with higher rails. That means you can use faster low voltage devices. I think those advantages are worthwhile.
-Chris
Cascoding allows you to run cooler with higher rails. That means you can use faster low voltage devices. I think those advantages are worthwhile.
-Chris
Hi Chris.
You are right. Just to add, cascode output is high impedance, in case we need it for voltage drive (like VAS), buffering allows to utilize cascode advantages. It is the way how to reduce distortion significantly. Overloaded cascode does not decrease distortion, the only merit is a constant voltage operation of preceding stage and decrease of capacitive load of the preceding stage.
You are right. Just to add, cascode output is high impedance, in case we need it for voltage drive (like VAS), buffering allows to utilize cascode advantages. It is the way how to reduce distortion significantly. Overloaded cascode does not decrease distortion, the only merit is a constant voltage operation of preceding stage and decrease of capacitive load of the preceding stage.
Hi all,
some time i read this forum and think about build my own symasym. Couple days ago i completed first channel. Tomorrow night I heared him firstly. Only mono for now and only on weak trafo (2x24V, 2A), but sounds very nice!! On weekend i will try both channels. I'm looking forward to listen.
Thank you Mike. You really have done great work...
pulec
some time i read this forum and think about build my own symasym. Couple days ago i completed first channel. Tomorrow night I heared him firstly. Only mono for now and only on weak trafo (2x24V, 2A), but sounds very nice!! On weekend i will try both channels. I'm looking forward to listen.
Thank you Mike. You really have done great work...
pulec
MikeB's output transistor advice
I remember reading a post by Mike regarding his impressions of the sonic qualities of different output devices for this amp. I've searched this thread and the other Symasym threads to no avail. Can anybody point me to that?
Thanks,
Ryan
I remember reading a post by Mike regarding his impressions of the sonic qualities of different output devices for this amp. I've searched this thread and the other Symasym threads to no avail. Can anybody point me to that?
Thanks,
Ryan
Hi Ryan,
In my experience, matching the complimentary gains is more important than the actual device used.
If you click on the "www" button under on of MikeB's or Pavel's posts, you will see what changes are required for different.
-Chris
Hi Pulec,
Good show. Did you match the diff pairs and drivers / outputs? I think you will really enjoy these.
-Chris
In my experience, matching the complimentary gains is more important than the actual device used.
If you click on the "www" button under on of MikeB's or Pavel's posts, you will see what changes are required for different.
-Chris
Hi Pulec,
Good show. Did you match the diff pairs and drivers / outputs? I think you will really enjoy these.
-Chris
Hi Guys,
I am on the way to finish my first diy amp, symasym, but i have a few questions.
Can I use MJ15024 and Mj15025 for the final transistor?
Can I change the 1000uf cap to 4700uf cap near the final transistor? Because i have original elna for audio 4700uf 45 v cap from thailand.
Thank you guys for your help.
regards,
Josh
I am on the way to finish my first diy amp, symasym, but i have a few questions.
Can I use MJ15024 and Mj15025 for the final transistor?
Can I change the 1000uf cap to 4700uf cap near the final transistor? Because i have original elna for audio 4700uf 45 v cap from thailand.
Thank you guys for your help.
regards,
Josh