Symasym - the next generation (supersym)

By Blueskynis - Why not store it in PNG format instead of BMP? PNG is a bitmapped image format that employs lossless data compression

Good idea , as far as storage , Blue. The reason for BMP (uncompressed) is that my PSP 7 expands it into ram (90 - 130MB) as I work on it, anyway.

I start with a 1200DPI uncompressed BMP and just work and update it as I progress with the layout. For schematics and the parts layout overview ,I store the draft in GIF/ JPG. But the screen and PCB must be super 1200.

At the end , I bring the PCB/silkscreen to 2 color BMP's (only 0,0,0 or
255,255,255) - 5megs then PDF them. I think my foxit PDF creator uses a real good lossless converter because I have extracted my 5 meg 1200DPI's from the PDF and see not one pixel amiss. :)
OS
 
Rafael, what you have posted is a triple output stage, which is essentially different from what OS is presenting here, while all other things remain near identical.

I am not sure whether it would be good for you to start another thread to post your amp. OS' has just finished and posted his PCB layout and having another amp, such as yours is not drawing the kind of attention that it would otherwise have. Or perhaps, in due time, the discussion between EF and Triple output stages would take centre stage.

Great work, OS and Rafael. Thanks.
 
Now it is done...

bY SAMUEL -Great work, OS and Rafael. Thanks.

You were premature , all 3 .. the schema , PCB , and silk , are in the PDF - "supersym_pcb-v1.0.PDF" (1.84mB) .... HERE:

http://71.236.32.49/pdf1/SUPERSYM_ASSD/

When labeling the silk , I double checked the component numbers with the schema , so I am sure they match. :)
I will do the BOM in a text file "supersymBOM.txt" (soon to come) along with a few hints and tips. BTW , I built BOTH of mine for $68 US dollars.
OS
 
Rafael.luc said:
In my version, short circuit protection begins work under 1 ohm load ouput, not affect the bass.

Good to see a schematic with some degree of protection featured. Most never try to include it, which is why I always layout my own pcb’s with it added.
However, I don’t understand how this arrangement will work. It seems to me that, with the values given, the protection transistor will trigger only when an output device tries to pass around 30A at any Vce; in other words, a horizontal locus parallel to the Vce axis at Ic = 30A.

Or have I completely misunderstood what it is intended for?

Regards,

Brian.
 
Ex-Moderator R.I.P.
Joined 2005
Right now I consider myself an expert in spotting board lines that could be done much simpler, nothing else
:D
The simple board layout i showed, and dare not mention, have been changed about a hundred times
Actually I ended up with using 1/3 of what I started out with, 1/3 of what I found half ways, and last 1/3 from how it ended

Could be a waste of time though, and may not matter much to sound anyway
I have a sickness of trying to perfect, and keep changing to the point where I cant find any better ways
That itself can sometimes turn into problems of its own :clown:
 
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Joined 2005
MJL21193 said:
I think there's more to a good layout than shorter or straighter traces.

Why do you question that yourself :)

I suppose it should be short where it matters, and longer where it matter less :spin:

This is not the same, I know, but you do know that when working with smd and ICs etc, and other high frequency stuff, it does matter a lot
If only just a little bit rubs of on other stuff as this, then its surely worth to consider
 
Samuel Jayaraj said:
Rafael, what you have posted is a triple output stage, which is essentially different from what OS is presenting here, while all other things remain near identical.

Differences are three: Triple Darlington Output, miller compensation which increased the Slew Rate to 90 Vus, I reduces the negative feedback to ~33dB

Samuel Jayaraj said:
I am not sure whether it would be good for you to start another thread to post your amp. OS' has just finished and posted his PCB layout and having another amp, such as yours is not drawing the kind of attention that it would otherwise have. Or perhaps, in due time, the discussion between EF and Triple output stages would take centre stage.

I do not have the pcb, I'm with little free time to do :xeye:
Samuel Jayaraj said:
Great work, OS and Rafael. Thanks.
:D

Pingrs said:


Good to see a schematic with some degree of protection featured. Most never try to include it, which is why I always layout my own pcb’s with it added.
However, I don’t understand how this arrangement will work. It seems to me that, with the values given, the protection transistor will trigger only when an output device tries to pass around 30A at any Vce; in other words, a horizontal locus parallel to the Vce axis at Ic = 30A.

Or have I completely misunderstood what it is intended for?

Regards,

Brian.

The operation is simple, resistors of the transistors output and most the resistor from the base of the transistor short-circuit, form a divider, from certain value the transistor begins to conduct, short-circuit input base of predriver, the values of resitores adjusted in simulator the value is 40 A, not to interfere in bass, attached simulation.

tinitus said:
My suggestions about improving board have been ignored
Well, I thought it was the point of this
Sorry if it was inconvenient
I didnt know it was done and ready to go
Good luck
I read your post, I believe it was for the pcb of ostripper, I am sure?
 

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Rafael.luc said:


I read your post, I believe it was for the pcb of ostripper, I am sure?


It was
Yours are a bit complicated and harder to "correct"
Ostrippers boards are easier to look at, and see what happens, and find the space for changes

Just from the hip I do remember small issues with yours that bothered me though
A few board traces where going nowhere, with no means, but still active
I didnt find it worth to mention at the time
Now I have

I wonder, was it you who offered payed board design assistance in the vendors bazar, a few days ago ?
Cant find that thread now
 
I find your work very interesting Though it seems to me like a lot of copper and very few components Im pretty sure the amount of copper needed could be much less with placing just a few components slightly different Several copper lines seem to wiggle a bit much in places where just a bit of rearranging would straighthen the lines, and naturally make it smaller Maybe also allow a few components to be mounted below board, if it makes layout much simpler And few jumper wires also makes sense, if it makes layout simpler Maybe also below board if needed or makes sense Seems to me that it gives possitive results to try and have as many resistors as possible as "jumpers" Regarding supply It looks ok, but I prefer to have a bridge on each secondary, so that common ground is at the end of supply One other point Please make it possible to use seperate supply on input section, with slightly higher voltage Looks like it already is readily possible, but Im not sure Below is a picture of how I like a supply, only this is a much smaller amp I have removed all coupling film caps that are not needed in terms of stability, making layout even simpler If anyone would insist on film coupling caps, it easy to mount them below board ehhh, its not 100% finished yet And yeah, I know, its a much simpler design


I read it , Tinitus !!
I will either agree or disagree , I still can change it.

" A lot of copper" ....
Not all are good solderers , I felt with the biggest pads , this rather hefty 225/350 watt amp would be easy for even an inexperianced constructor. The input stage lines are kept smaller and wrapped by the "lifted ground" . I have (am) listening to silence (absolute) , because of this.

"Higher voltage for VAS/LPT" , It is there.. (lift R44/45 , put in 2 wires, AOK)

" No coupling film caps" That one I will disagree on. So will the big caps when you play 4khz synthesizer square and sawtooth waveforms at 200watts. :bigeyes:

I was not sure who's artwork you were referring to but I have no problem "absorbing" any good technique . It must have worked because in the real world there are NO issues. The one "BUG" with this PCB is the HF cap (X to X) and (G to G) , which is the zobel ground return to star.(2 wires beneath the board)
OS
 

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Screwup Alert..

I AM A IDIOT !!

I reversed the inverting and non -inverting LTP feeds to the VAS, It is now corrected. DO NOT use the PDF I submitted yesterday !!!

The new one is in there now. Sorry ,I don't know how that one got by me. I REALLY looked it over ..maybe "supersymPCB_V1.1.pdf"
yeah.. :cool:


OS
 
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Joined 2005
Did I make you look again :D just joking :smash:

But I have a small request

Please, make the silkscreen so that we could easily see where the transistors are located, and oriented ;)
Its almost easier to find transistor location by looking at copper lines
And the mirror imaged silkscreen doesnt make it easier
It would be nice to more easily spot the components

And I probably need better glasses:clown: