I am just looking at the PCB layout on author's site, and some of the traces look quite thin to be connecting 0R22 5W resistor with output transistor? Am I missing something?
if the gain of the Symasym is reduced then the phase margin and the gain margin will change.
Simply changing some compensation may not be accurate enough to restore the gain and phase margins. This is a skilled job that needs experience and tools.
Don't try this at home.
Simply changing some compensation may not be accurate enough to restore the gain and phase margins. This is a skilled job that needs experience and tools.
Don't try this at home.
Ok Andrew thanks for advise. Perhaps adding this information on symasym pages won't be silly since i simple quoted what was written on.
Personnaly i don't play with gain on any design since i have not enough experience and perharps not the right probe material to test.
Marc
thanks for everything people! i have my symasym complete and working great. the sound quality is awesome and very good output power.
sorry about my english.. im from argentina and i can read very good but not so very good for write.
thanks!
sorry about my english.. im from argentina and i can read very good but not so very good for write.
thanks!
I didn't read the whole thread (too many pages).
Has anyone mentioned this amp has a striking resemblance to Trace Elliot bass amplifiers?
Has anyone mentioned this amp has a striking resemblance to Trace Elliot bass amplifiers?
I think I have read the whole thread over time. The answer to your question is "no". Apart from that, SymAsym also seems to be a lot like the ultra expensive Goldmund HiFi stuff. These days it's not easy to come up with a really new topology. So what?
I think it is nice to give credit for the inspiration, when posting a new design.
Anyway not really picking on anyone here.
The comment is actually an endorsement. Trace Elliot is my favourite bass amp.
Anyway not really picking on anyone here.
The comment is actually an endorsement. Trace Elliot is my favourite bass amp.
Hi!
Can I power this amplifier with 50V rails, maybe adding one more pair of output transistors? Seems to be fine in my simulation.
Regards,
Paulo.
Can I power this amplifier with 50V rails, maybe adding one more pair of output transistors? Seems to be fine in my simulation.
Regards,
Paulo.
You would definitely need the 2nd pair (at least), BUT VAS current and allowed power dissipation is low in the original design.
Ostripper has redesigned the circuit for higher power here, it may be what you're looking for:
http://www.diyaudio.com/forums/solid-state/169590-mongrel-supersym-ii-5.html
- keantoken
http://www.diyaudio.com/forums/solid-state/169590-mongrel-supersym-ii-5.html
- keantoken
Thank you, but does it has the same sound quality of the Symasym 5.3?
I have been told the higher power versions based on the Symasym don't sound quite as good as the Syasym 5.3. Is it true or not?
I have been told the higher power versions based on the Symasym don't sound quite as good as the Syasym 5.3. Is it true or not?
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I just realized you've been posting in that thread. I wouldn't know how good the sound is.
If you want to stay close to the original i would recommend to add outputs like you described, and follow Pavel's advice and upgrade the VAS's with those used in the Mongrel. I think the MPSA18 also would need to be changed for higher rails, or you could cascode them to the original 36V Vce.
Hmm, I wonder if 36V rails are the "sweet spot" for amps?
- keantoken
If you want to stay close to the original i would recommend to add outputs like you described, and follow Pavel's advice and upgrade the VAS's with those used in the Mongrel. I think the MPSA18 also would need to be changed for higher rails, or you could cascode them to the original 36V Vce.
Hmm, I wonder if 36V rails are the "sweet spot" for amps?
- keantoken
Definitely, the MPSA18 would not make 2 x 50V rails. I have overlooked it, as I use BC546/BC556.
Regarding 36V rails, they are "safer", especially for beginners. 2 x 50V rails need more concerns about SOA, Vce, Ptot etc.
Regards,