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LSK pre - BAF 2013
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Old 11th January 2018, 09:13 PM   #541
Hikari1 is offline Hikari1  United States
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Originally Posted by Hikari1 View Post
Attachment 655655

I did in fact add more feedback...520R/150R was as close as I could get to what you suggested. The sound is a little bit more lively now. Seems like a little less gain too? Not sure which I prefer, the original has a smoothness and silkiness I like. But I will have to listen for a while and see.

Also, while the circuit seems DC stable in a temp controlled situation it does fluctuate a bit (20mv or so) with temp changes. It probably doesn't help that my phono amp with shut regs is on top of it. I will leave the cps for now.

Still impressed. Thanks Juma.

After playing with the feedback values I think I like 680/150R, your original values, the best. It has a smooth, airy sound I like and the widest soundstage.

I'd like to try a buffer on output. Why? Might get some more low-end dynamics and keep the airy highs without changing the feedback values. Also, might be awesome for headphones.

Do you have any recommendations?

Currently I am thinking about using the output stage from Wayne's Pass DIY headphone amp (attached) since the bias mechanism is convenient.
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Old 12th January 2018, 09:45 AM   #542
juma is online now juma  Germany
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If you want to drive headphones, it's OK.
If you just want low Zout, a simple JFET Source follower at the output would be enough, like this:
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Please don't use private messages for question related to audio projects. It defeats the purpose of the forum.

Last edited by juma; 12th January 2018 at 09:49 AM.
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Old 14th January 2018, 04:43 AM   #543
Hikari1 is offline Hikari1  United States
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Join Date: Jun 2012
Location: Seattle
Thanks Juma. That is good info. Currently Iam playing around with coupling caps to see if I can get it where I want it without adding another stage. Believe it or not, right now I have a 100uf Silmic cap on output bypassed by a poly cap and it sounds very good. I like the original lower feedback values. But at this point it’s really more tweaking than anything.
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