Ostripper, see if you can do better than this. Make sure OL phase is at -57 degrees @ 0db so we know you'll get the same results as I did.
- keantoken
- keantoken
Mongrel.txt contains all the necessary models for the simulation. It only needs to be in the same directory, and LTSpice will use it's contents when it scans the ".include mongrel.txt" command in the schematic. This is included so that the same device models are used whenever the file changes hands. This way we all get the same results.
- keantoken
- keantoken
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Joined 2009
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It seems to me that this could be the 2010 DIY Audio SS reference amp. If so, pcb's from a vendor might be the way to go (no toner transfer).
Hey , keen read post #485 ,#487 ,and #489. Here ... http://www.diyaudio.com/forums/solid-state/133306-frugalamp-os-49.html#post1691340
It is optimal for the phase to start at 0 dg , slope to a shelf of -90 / -100dg , and not dropping past that until after the unity gain point. Using these rules , I stabilized all the frugalamps and my present supersym (1 year old
).
Detailed explanation is here : http://www.diyaudio.com/forums/solid-state/133306-frugalamp-os-48.html#post1691281.... Post #474.
Good info ,better sounding with no burning amps since.
OS
It is optimal for the phase to start at 0 dg , slope to a shelf of -90 / -100dg , and not dropping past that until after the unity gain point. Using these rules , I stabilized all the frugalamps and my present supersym (1 year old
).Detailed explanation is here : http://www.diyaudio.com/forums/solid-state/133306-frugalamp-os-48.html#post1691281.... Post #474.
Good info ,better sounding with no burning amps since.
OS
Did you extract the zip file to a folder before you opened it? LTSpice can't look inside zipped folders.
- keantoken
- keantoken
Hey , keen read post #485 ,#487 ,and #489. Here ... http://www.diyaudio.com/forums/solid-state/133306-frugalamp-os-49.html#post1691340
It is optimal for the phase to start at 0 dg , slope to a shelf of -90 / -100dg , and not dropping past that until after the unity gain point. Using these rules , I stabilized all the frugalamps and my present supersym (1 year old
Detailed explanation is here : http://www.diyaudio.com/forums/solid-state/133306-frugalamp-os-48.html#post1691281.... Post #474.
Good info ,better sounding with no burning amps since.
OS
I haven't a clue what you mean, there is nothing wrong with my file or the way I measure open-loop gain.
- keantoken
Andrew , here's the latest .. no text needed. Models as directive (on simulation).
Don't want amp of the year. 😀 Must make the prototypes (toner transfer) first to probe it to death with my scope and do an audition/tweaking.
OS
Don't want amp of the year. 😀 Must make the prototypes (toner transfer) first to probe it to death with my scope and do an audition/tweaking.
OS
To get the text out of the way right click on it and select "not visible". This hides it without changing the simulation.
- keantoken
- keantoken
Keen, read #474 ,then look at the example by mjl21193(post #487). I posted because I got strange results from your asc.
Try the new one , it is nearly optimal. (according to #474)
OS
Try the new one , it is nearly optimal. (according to #474)
OS
Two part boards are good , if you tinker , you won't have to rip up the big stuff ! Driver trannies are best on the main HS. It takes the ambient (case , room) out of the thermal comp. 😎 A mosfet (verticle irf240/9240) should be the same as my njw0281/0302's. For mosfet , feel free to use mje340/350's as drivers.
OS
A little messup .."mongrel sim.zip" was the operational simulation. Below is
"mongrel sim2.zip" , which is the loop gain sim.
right click on screen , "add trace" (ctrl +a) , expression -V(vout)/ V(a) ..done.
OS
"mongrel sim2.zip" , which is the loop gain sim.
right click on screen , "add trace" (ctrl +a) , expression -V(vout)/ V(a) ..done.
OS
What expression for loop gain ?? I am into gaining anything.
OS
edit : andy c's _x OPS models are not included in mongrel.txt Not a condemnation , just an observation.
OS
edit : andy c's _x OPS models are not included in mongrel.txt Not a condemnation , just an observation.
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There is a comment under all the simulator commands that contains the OLG trace, I should have indicated it somehow. Plot "-V(vout)/V(vx)".
Sorry everyone, I included the wrong Mongrel.txt in the last upload! Use this one instead.
- keantoken
Sorry everyone, I included the wrong Mongrel.txt in the last upload! Use this one instead.
- keantoken
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I found your old mongrel.txt ... here is what I got (-61db)
why did you add 1khz to v5 ?
below is the loop gain plot I generated.
OS
why did you add 1khz to v5 ?
below is the loop gain plot I generated.
OS
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