So cviller added the cascode option to the board (I couldn't remember what happened about that)?
Where did you get those washers on the mosfets from?
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Its been a while since I built an amp, just ordered the boards from the store. Last time I built and amp was back in like 2001. Had to take a DIY audio break, as 3 kids consumed all extra time and $resources$. Looking forward to building a new heater for my listening room, wait I live in Florida, Nelson could you make amp that sucks heat out the air please. I find myself loosing sleep again at night thinking of different circuits and mods. Time pull the heatsink extrusions (those chunks of metal) as my wife calls em out of the corner of the garage.
Now to find, beg borrow or steal a some elusive Toshiba 2SJ109. Any one have some laying around that aren't needed?
Chad
Now to find, beg borrow or steal a some elusive Toshiba 2SJ109. Any one have some laying around that aren't needed?
Chad
The input JFET pair should be matched. Maybe not an exact, very close match but, not just purchasing 2 (per channel) off the shelf devices. I would suggest chasing down Blues or someone with a copuple matched devices for sale at a reasonable $$$ for a good start on your amp. it's a good place to spend a few extra bucks 
Yeah, tracking down the 2SJ109 is really tough. We assumed that most people will use two discrete JFETS. They should work..
Well obviously I'm not Nelson but, there are 3 distinct stages of gain here. The input stage consisting of the JFET diff amp providing some voltage gain and taking feedback from the next stage. It drives the single N MOSFET common source "VAS" second stage for most of the voltage gain and enough current to drive the third, output stage. The output of this stage is also fed back to the diff pair. The output follower stage only provides currnet gain to drive your low impeadance speakers. 3
Variac,
Thanks for the quick shipment. Got my set of boards today.
Has anyone put a BOM together for the BA2 or do I have do it the old fashion way? (Didn't find one doing forum search)
Nelson,
Would you like to donate a set of 109's to good home since it looks like all the Burning Amps that you donated where not put to use with the input board you designed? (you don't know unless you ask, plus you would be able tell people William Shakespeare listened to your amps) On another note Nelson I just wanted to say thanks for your sharing of info with all us diyers. I've been member here since 2001 and you have shared lots of your intellectual property since then and I look forward to future projects. ie. The DAC.
Since I know the above is a very very longshot, where is the best place to source the 74BL's from? Any body use the guys on Ebay that claim to be matched pieces?
Thanks in advance,
Chad
Thanks for the quick shipment. Got my set of boards today.
Has anyone put a BOM together for the BA2 or do I have do it the old fashion way? (Didn't find one doing forum search)
Nelson,
Would you like to donate a set of 109's to good home since it looks like all the Burning Amps that you donated where not put to use with the input board you designed? (you don't know unless you ask, plus you would be able tell people William Shakespeare listened to your amps) On another note Nelson I just wanted to say thanks for your sharing of info with all us diyers. I've been member here since 2001 and you have shared lots of your intellectual property since then and I look forward to future projects. ie. The DAC.
Since I know the above is a very very longshot, where is the best place to source the 74BL's from? Any body use the guys on Ebay that claim to be matched pieces?
Thanks in advance,
Chad
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