It is strange. I search for "glasui" and found nothing
I think I get file "glasui.asc" from OS.
Mistress amp. I saw this thread this morning. Killer looking square waves. Looks like the front end would be a good candidate for the Slewmaster. what do you guys think?
Hi Vostro,
Yes, the AX-14 sounds very nice. I have built three versions counting this one. Simple and common parts. Great for DIY.
So what's next? Anyone have a new IPS to try? How about that PSU circuit Valery? I'll be finishing up a TMG8 when the rest of my parts get here and then I'm going to need something to work on.
You could always look at APEX SR200 ips and vas.
Regards
Why did OS abandon GLASUI and develop SYMASUI?
GLASUI have 3 stage voltage amplification and SYMASUI just like SYSASYM with improved VAS.
I sim both IPS, and GLASUI have better THD than SYMASUI.
OS, please come back here soon....
There is nothing stopping us from doing the GLA as an IPS. I'll grab the files from the original thread and work on this soon. This is the beauty of this project, we can do whatever we want and try it for ourselves. Even tapping into other projects as some of us have successfully done.
Hi Guys,
Speaking of Symasui, I have a few extra boards so I was trying to think of something to do with them when I got the idea to try making a small amp out of a pair. The MOSFET discussion got me wondering about laterals because they take fewer components. I put together a spice file to try it out and Jason was kind enough to help me get it working. Before I build it, I thought I would post it here so some of you could take a look and make suggestions.
Thanks, Terry
Speaking of Symasui, I have a few extra boards so I was trying to think of something to do with them when I got the idea to try making a small amp out of a pair. The MOSFET discussion got me wondering about laterals because they take fewer components. I put together a spice file to try it out and Jason was kind enough to help me get it working. Before I build it, I thought I would post it here so some of you could take a look and make suggestions.
Thanks, Terry
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I don't know about GNFB. This is simply the Symasui IPS with a VBE multiplier and a couple lateral MOSFET's as the OPS. The IPS does have a servo. The IPS is the one that Jason is selling boards for. Another learning exercise for me. Specs aren't nearly as good as with the Slewmaster OPS but considering it only has a handful of parts it seems like worth trying.
terry:
just had a very quick look at the schematic.
two things hit me right away:
1. i wouldn't build this unless i wanted to smoke the cascodes Q3 & Q4; they are not biased properly
2. if D6 is really an LED, (lets say it's red) is 1V across Q11 and Q12 really enough for them to operate properly? i'd guess not ...
there's more, such as <1ma seems small amount of bias for LED D6 to be used as a voltage reference ...
mlloyd1
just had a very quick look at the schematic.
two things hit me right away:
1. i wouldn't build this unless i wanted to smoke the cascodes Q3 & Q4; they are not biased properly
2. if D6 is really an LED, (lets say it's red) is 1V across Q11 and Q12 really enough for them to operate properly? i'd guess not ...
there's more, such as <1ma seems small amount of bias for LED D6 to be used as a voltage reference ...
mlloyd1
I finally have some time and parts in hand. I'm sure this will be the first of many questions.
For a 5 pair mosfet output witch would be preferred for Q107/108
http://www.mouser.com/ds/2/149/FJL4315-53840.pdf
http://www.mouser.com/ds/2/308/MJW3281A-D-107810.pdf
The njw parts specified were unavailable.
They look similar. The Fairchild parts have a lower output capacitance.
Thanks, Evan
For a 5 pair mosfet output witch would be preferred for Q107/108
http://www.mouser.com/ds/2/149/FJL4315-53840.pdf
http://www.mouser.com/ds/2/308/MJW3281A-D-107810.pdf
The njw parts specified were unavailable.
They look similar. The Fairchild parts have a lower output capacitance.
Thanks, Evan