L'Amp: A simple SIT Amp

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. 🙂
 
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? 😀
 
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!! :crazy:
 
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? 🙂
 
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.. 🙂
 
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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.