After all these years of waiting, almost a reality dream is coming true . Here you can see the emblem of Pass products line, " THE BLUE LED " IS ON.
- -v = 44.1 vdc +v = 44 vdc Across -v +v = 88.7 Across R14 = 4.7 Across R11 = 4.98 Z5 = -8.92 Across Q5 = 4.70 Across Q4 = 4.72 DC offset = 18.6 mv What do you guys think of these measurements ? and is getting
can leave my hand for about 20 sec. Do I need more testing before listen to the music.?
Before Hooking it up to a speaker, I'd check the voltage across the Source resistors - they should be quite consistent, at least within the output stage and within the CCS. This will tell you what you ended up with for bias. Not really necessary but will help verify that the amp is working as designed.
You may also want to see how it behaves unloaded while being driven. Check offset and that you are amplifying.
Sounds like you are almost ready to listen to an Aleph!
You may also want to see how it behaves unloaded while being driven. Check offset and that you are amplifying.
Sounds like you are almost ready to listen to an Aleph!
That's great news!
Yeah, check those source resistors. If its pulling the rails down that much it must be biased pretty high, not that it is a bad thing.
Yeah, check those source resistors. If its pulling the rails down that much it must be biased pretty high, not that it is a bad thing.
I did not connect R19 to bias very high and like Mr. Pass suggested to connect a filter capacitor across Z5.
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I can say DC offset is very stable (19.5 mv), drifting a little bit down. I think is time for this. 
Errr - suggestion. If you have some "test" speakers ya should go with them 1st. 🙄
Gee - it's been really great to see all of those with knowledge and skill helping out - inspiring!!! 😀😀😀
BTW - what are your speakers? Or is a really nice set of those the next project (ya can't have enough projects!!!). 😎
Gee - it's been really great to see all of those with knowledge and skill helping out - inspiring!!! 😀😀😀
BTW - what are your speakers? Or is a really nice set of those the next project (ya can't have enough projects!!!). 😎
An inexpensive spkr for starters is a wise suggestion.
Before I forget, after you're done for the night and shut it down, wait a few minutes then check the temp of your inductors. You are pulling quite a bit of current through them.
Before I forget, after you're done for the night and shut it down, wait a few minutes then check the temp of your inductors. You are pulling quite a bit of current through them.
I have some for testing. You are right, all this guys are Marvelous ! This is a great wonderful forum. I have some little nice speakers, ones were my designs, others modifies and some are commercial ones .
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