L'Amp: A simple SIT Amp

my last try in the CCS....

you see in the picture that I am a bit old.....

I do not why, but with the 500R pot I manage to get a good mixture of the K2 and k3. Either in series with the cap or parallel to the resistors like now...

without the pot it was much more difficult to get the right mix only by the SIT bias pot and the SS bias pot at the recommended values....

I hope I write no nonsense.....

Of course I would be happy if anybody on his journey could test the 500R pot idea too and possibly confirm the use of it.:D

To me it looks more like a Gyrator than a CCS...:)
 
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To me it looks more like a Gyrator than a CCS...:)

Hi Skorpio,

I hope you do not mean this, it was used for maniacs and I am only a Pass Junkie!:D:D

346px-Cox_Swing.gif
 
Let's use that lab supply as a voltage source, get a proper drain load resistor in there, and give it another try.

Drain resistor:up:
Tested also with quality bookshelf speaker. Sounds promising. I think I was getting around 5 watts peak close to 7v rms without noticing any distortion with my 30v supply. Drain resistor was around 8 ohms(8//68R 10 watt resistors) , bias 4.5v, Vds 13v. I will put a scope on it soon. For efficient 8ohm speakers 95+ db and smaller rooms even 30v ps with drain resistor combination would be enough I guess.

The power supply "ccs" seemed like a good idea but it is probably too "slow" to deal with music signals.
 
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They stick those ''current source mode'' labels on switches and they mean current limit most of the times especially the Mastech, V&A, and the like relabeled bench PSUs. That is why I picked that hint out when I saw your post about weirdo behavior and that config. Nice it got solved so simply.
 
I could try to find a 195 label from mine... But, all I gotta say is, they were made in Canada, like mine, and if we don't use 'em they will be in our junk box until we do! Mine was rated at 100mH but, I asked them to do a measurement at 3A and they tested them at 130mH! Shipping makes them eeexxxppppensive! They're really great for a pre or head phy PSU too!
Go gerd!!
I will be "reconstituting" mine in epoxy with vaccum eventually. Even if they do get excessive with the physical stuff, they would be great on my 120-3K mid line!
I'm not done yet :Pawprint:
 
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Hi Lee, :)

the label was from google...I ordered them here in Germany ..delivery time 14 days...so I suppose these will not come from Canada, because all mail I got from there, lasted a very long time, up to 6 weeks...
Yes I have seen some people using them in a PSU..... must be good....

I do not dare to say...
(because I did not test his second CCS suggestion for the SIT)

....but Salas might give us a new idea for the SIT-PSU, besides the suggestion Mike made..

so Junanitox may be your soldering iron must work again....:D
 
Yes, I was useing them as a load for a ZV9 and up above 1A, and 100Hz, they worked well but, at about 3k they became a transducer! I think , as Mike said, it's only during peaks! I was doing full power sine waves(you really should almost never do that!). But I think with a little Vacuum empregnated epoxy most of the radiated sound will be many DB down! I will give it another go :Pawprint: But I want to finish my F5 and a few other projects!
:D