I know a couple of readers had their hearts set on something active, so here you go:
L'Amp CCS Addendum
L'Amp CCS Addendum
nice! what difference on sound vs choke ?
PS
on tube ,for some choke is preferred to ccs ,less dry/analytic
PS
on tube ,for some choke is preferred to ccs ,less dry/analytic
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The CCS versions I have listened to sound very good, but in my opinion don't sound as "big" or as "snappy" as their passive counterparts.
In that sense, they sound a bit more "conventional" while maintaining a touch of the SIT magic. The midrange is particularly nice.
For the moment, I still prefer the big dumb versions. 🙂
In that sense, they sound a bit more "conventional" while maintaining a touch of the SIT magic. The midrange is particularly nice.
For the moment, I still prefer the big dumb versions. 🙂
Thank you Michael. But, I can't get the CCS link from work 😡
Hey, Some time back I played with the ZenV9 circuit using a big Hammond choke load instead of Aleph. Actually, I think it worked quite well. But, 1 thing that it did do that is somewhat of a problem is it made physical, vibrational noise with signal. It was a frequency/amplitude sesitive thing (maybe started around 3k?) but, quite audible. I believe they were spec'd well enough for this amp (3-5A, .64 ohm, 100+mH IIR)
You might never notice this phenomina unless you test with a resistor load. Have you noticed this problem? Can you hear your amp without any speakers?
I don't know if it's the E-Core Lams or the windings or? I wonder if impregnating epoxy resin into the windings will stop this or?
Great work! But, ya know, I was kinda hoppin you where gonna duex a mu follower or somthin? 😀
Hey, Some time back I played with the ZenV9 circuit using a big Hammond choke load instead of Aleph. Actually, I think it worked quite well. But, 1 thing that it did do that is somewhat of a problem is it made physical, vibrational noise with signal. It was a frequency/amplitude sesitive thing (maybe started around 3k?) but, quite audible. I believe they were spec'd well enough for this amp (3-5A, .64 ohm, 100+mH IIR)
You might never notice this phenomina unless you test with a resistor load. Have you noticed this problem? Can you hear your amp without any speakers?
I don't know if it's the E-Core Lams or the windings or? I wonder if impregnating epoxy resin into the windings will stop this or?
Great work! But, ya know, I was kinda hoppin you where gonna duex a mu follower or somthin? 😀
This is not an issue with a big, heavy ga. air-core.
Iron is another matter, though.
Be sure to grab that pdf when you get home. 🙂
Iron is another matter, though.
Be sure to grab that pdf when you get home. 🙂
This is not an issue with a big, heavy ga. air-core.
Iron is another matter, though.
Be sure to grab that pdf when you get home. 🙂
hi michael , i actually enjoy l'amp fig 11 with a bypassed source resistor , can i keep the same config with the inductor load?
where to find a source for this heavy gauge air-core?
i can't imagine this thing can sounds even better with CSS or inductor load ?!
amazing!!

Well, you'd need even more source resistance to set the operating point properly. It doesn't seem like a particularly attractive idea to me, but you should follow your heart.
Eventually, you'll want to get your voltage references working. These really shine with no degeneration, and I think you'd do well to focus your effort there. I have, after all, posted a working schematic which you can easily build on perfoboard.
Would a PCB sway you? 🙂
Eventually, you'll want to get your voltage references working. These really shine with no degeneration, and I think you'd do well to focus your effort there. I have, after all, posted a working schematic which you can easily build on perfoboard.
Would a PCB sway you? 🙂
so for you : first choice is inductor load , second CCS load and third bulb/resistor load. and last my config resistor load with source resistor
i'm out again ...😀😀😀
that's why i have to learn .. so i will repair my bias module and try again with it, so just have to change the power transfo from 40V 800VA to 28V 400VA and try CCS first, before i could find an big 100mh aircore somewhere.. 🙂
i'm out again ...😀😀😀
that's why i have to learn .. so i will repair my bias module and try again with it, so just have to change the power transfo from 40V 800VA to 28V 400VA and try CCS first, before i could find an big 100mh aircore somewhere.. 🙂
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I think the bulb versions and the inductor version are somewhat similar. The inductor version has the advantage of being quieter, more efficient with higher power, higher gain, and no turn-on thump (but it doesn't glow in the dark).
IMO, the CCS versions come in after that.
At least until I change my mind.
IMO, the CCS versions come in after that.
At least until I change my mind.
IMO, the CCS versions come in after that.
At least until I change my mind.
call it Constant Change Sit .... 🙂
call it Constant Change Sit .... 🙂
I will say this: I keep going back to the inductor vesion despite the fact I have to lug them up two flight of stairs to my listening room.
I'm not sure why this is, but that's the data. 😎
I assume you're not talking about the energy required for me to carry them upstairs.
So now my curiosity is piqued. I hope you'll elaborate.
So now my curiosity is piqued. I hope you'll elaborate.
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