Temporary cooking instead of my F6 🙂
Should be making music soon!
Thanks Zen Mod!
Following your instructions from the build thread was a breeze. Only had trouble with a faulty 10k pot for the offset - had to go with a 5k and a somewhat larger R18. But it seems to be stable and all good!
My THF51s from watanabetomoaki wasn't really matched, but it will have to do for now 😉
Should be making music soon!
Thanks Zen Mod!
Following your instructions from the build thread was a breeze. Only had trouble with a faulty 10k pot for the offset - had to go with a 5k and a somewhat larger R18. But it seems to be stable and all good!
My THF51s from watanabetomoaki wasn't really matched, but it will have to do for now 😉
Attachments
looking good!
common mode chokes could be better , but not really sure for SissySIT , due to uneven loading of rails - Mosfet is always doing much harder work than SIT , so load on neg rail is greater than on pos
Ugs matching of THF is not critical , as long you're able to set Iq , who cares for Ugs difference
common mode chokes could be better , but not really sure for SissySIT , due to uneven loading of rails - Mosfet is always doing much harder work than SIT , so load on neg rail is greater than on pos
Ugs matching of THF is not critical , as long you're able to set Iq , who cares for Ugs difference
Twst, that amp looks great !
I like the three-dimensional Meccano-style construction that enables your "significant" power supply ...
It is a pity to hide the beautiful Toroidy transformers inside the amp ...
In my build, I'm happy with 4 pieces in my PSU of the little brother of the chokes you used - 156B (1.5 mH, 5 A, 70 mOhms).
SissySIT is absolutely deadly totally silent on my 100 dB/W widebanders. 😛
I'm listening to it at the moment - it's the most transparent and informative and also explicit amp in my system so far, very nice tone, nice bite where necessary as well, not too aggressive. It's hard to do something else (like reading this forum) while listening, which in my book is a desirable quality 😀
Thanks, Zen Mod, for this amp ! 🙂
Best regards,
Claas
I like the three-dimensional Meccano-style construction that enables your "significant" power supply ...
It is a pity to hide the beautiful Toroidy transformers inside the amp ...
In my build, I'm happy with 4 pieces in my PSU of the little brother of the chokes you used - 156B (1.5 mH, 5 A, 70 mOhms).
SissySIT is absolutely deadly totally silent on my 100 dB/W widebanders. 😛
I'm listening to it at the moment - it's the most transparent and informative and also explicit amp in my system so far, very nice tone, nice bite where necessary as well, not too aggressive. It's hard to do something else (like reading this forum) while listening, which in my book is a desirable quality 😀
Thanks, Zen Mod, for this amp ! 🙂
Best regards,
Claas
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though , I have few things to complain about Twst's work:
-base plate is wrong oriented , lip better to put up , so no waste of space under it - one can place all mains cables beneath
-signal cables are too thick
-his work space is too tidy
🙂
-base plate is wrong oriented , lip better to put up , so no waste of space under it - one can place all mains cables beneath
-signal cables are too thick
-his work space is too tidy
🙂
Thanks! 😉
Chokes was just an experiemnt - I dont think they to much different than resistors - but they certainly add up weightwise giving the amp a good feel in my back when moving it..
Yuup, seems fine - SITs reads 2V6 and 3V5 @ 23v 2A and biases up fine. Had to mess a little with the offset adjustment of the highest one, but changing R18 did the trick
Thanks mate! 😉
I know they are in there - makes me sleep so much better 🙄
Of course you do 😀
Pfft, gives more air and room for screws to not scratch anything 😛
Should 15cm cable make a difference, it the same cable all the way to my sources 🙄
You haven't seen my other tables where I actually do the work 😀
And for sound - this thing is unique. Especially in the top end. It is really pulling out all the details and even the details in the details. It's not sounding anything like the M2 or the other firstwatt builds of mine, that's for sure.
Feeding it directly form my Katana gives a large soundstage in my horns on top of the cornscala bass cab.
There are no noise or hum coming from this amp, and that's cool. Had some mu-metal ready for the input autoformers - but it doesn't seem necessary at all.
As for the details, it kinda seems over the top with some recordings - making it somewhat bright/fatiguing. But not the regular sibiliant kinda bright. Might settle after a while - but overall I am impressed with the involving soundstage of this thing 😉
And oh, it runs a little hotter than I expected. Its like aleph hot!
Now, back to music
@Twst - it'll settle ..... everything needs some burn in , caps in PSU , Iron , little Elna ....
our Italian friend found that he prefer higher voltage 1uF MKC as bypass for Elna Silmic (vs. these MKC I'm sending) , but I can't confirm - didn't tried and ....... I'm blessed with some time spent with Elephants , so my ears are much easier satisfied than ears of regular Greedy Boy
our Italian friend found that he prefer higher voltage 1uF MKC as bypass for Elna Silmic (vs. these MKC I'm sending) , but I can't confirm - didn't tried and ....... I'm blessed with some time spent with Elephants , so my ears are much easier satisfied than ears of regular Greedy Boy
SissySIT option 2 kit has arrived in Arkansas.
Now to re-read the thread before I heat up the soldering iron and lay my probably too eager hands on it.
Now to re-read the thread before I heat up the soldering iron and lay my probably too eager hands on it.
funny - never before happened - 3 kits delivered in same day in USA 🙂
do not forget reading this thread : Babelfish M25, SissySIT - general building tips and tricks
if in doubt with tiniest thing , ask
do not forget reading this thread : Babelfish M25, SissySIT - general building tips and tricks
if in doubt with tiniest thing , ask
please , clarify question ;
maybe reading this post (#1) will help : Babelfish M25, SissySIT - general building tips and tricks
maybe reading this post (#1) will help : Babelfish M25, SissySIT - general building tips and tricks
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+ can be only typo
it is negative , SIT being depletion device , so normally ON
to brake it (current) one need to apply neg. voltage , same as Vacuum Tube
it is negative , SIT being depletion device , so normally ON
to brake it (current) one need to apply neg. voltage , same as Vacuum Tube
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Thanks, Zen. This clears up the confusion that was in my head! I just ordered two sets from Pras: one pair at 3.37v and another pair at 3.34, so I have a backup pair.
Got this clarified by Cinemags. There is no difference between the left and right transformer. All is good now.
You have to look at one of them in mirror, then it is clear.
I am paranoid about silly details as well! Must clear head of all doubt, if way mess up, I will find it even if requiring quantum physics.
Head must be cleared of all sillyness before solder is applied. I am master of anvil destruction with rubber hammer.
Russellc
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