"whichever way you find adequate" was written taking in account possibility that pcbs are already on heatsink and that you're checking P1 fiddling with pins of neighbouring parts
that's usually tin foil hat time , needing some staring at goats and schematic , to decypher which parts and which leg of these are exactly connected to P1
in case when pcbs are still free to mingle in hands , simply put probes between solo pin and (now soldered together) pair of pins of P1
simple as that
Gotcha - "Pineapple Express"

Did changing the resistors have any audible beneficial impact?
since the Sissy is really an amp that sounds wonderful I decided to refine his qualities. I thought of placing in key points of the circuit where the signal passes some valuable component.
I added the components one at a time to understand how much weight they had in the final result.
then R1 = Vishay z-foil (TX2575), R2 = Caddock MK132, R20 R21 R-flying = Dale RN55.
But the biggest impact on sound was the comparison between capacitors. I was intrigued by ZenMod's suggestion to adopt the old Philips MKC in polycarbonate in parallel to the Silmic II ...... and as I had a pair of 4.7uF Clarity Cap CSA I put them in competition.
having listened carefully to the coupled Silmic + MKC he won tremendously. I invite everyone to try ..... I think nobody will repent.
I am very satisfied at this point .... great sound 😀
Hi Zenmod,
What is the value of the capacitor that you put across the secondary on the bridge rectifier on your Sissysit build. Is it calculated or first capacitor on top of the part bin?
Hubert
What is the value of the capacitor that you put across the secondary on the bridge rectifier on your Sissysit build. Is it calculated or first capacitor on top of the part bin?
Hubert

the SissySit is an amp that really sounds greatDid changing the resistors have any audible beneficial impact?

For me it sounds in a way that makes you forget that it exists ..... but you can no longer change it with nothing for you. in the order of impact on the final sound I place:
- First .... Trafo Cinemag
-second ... inter-stage cap (Mundorf Supreme + Philips MKC "yellow" or alternatively SilmicII + MKC)
third .... Z-foil (TX2575) for R1
the rest is not touched.
Thanks, I am still waiting for my Cinemag transformers to arrive.
the SissySit is an amp that really sounds great. The things I suggested concern refinements that embellish his qualities.
For me it sounds in a way that makes you forget that it exists ..... but you can no longer change it with nothing for you. in the order of impact on the final sound I place:
- First .... Trafo Cinemag
-second ... inter-stage cap (Mundorf Supreme + Philips MKC "yellow" or alternatively SilmicII + MKC)
third .... Z-foil (TX2575) for R1
the rest is not touched.
Hi Zenmod,
What is the value of the capacitor that you put across the secondary on the bridge rectifier on your Sissysit build. Is it calculated or first capacitor on top of the part bin?
Hubert
![]()
thumb of rule cell from Yore - 1K+1nF
didn't had time to make Quasimodo
go figure level of my laziness

go figure level of my laziness![]()
Ahaha I was kind of lazy too that why I was asking 🙄
All the parts for the Sissysit are coming along, should be able to begin the assembly as soon as I received your boards that must be stuck at the Canadian border and... the cinemag trafo..
Merci !
Hubert
Ahaha I was kind of lazy too that why I was asking 🙄
All the parts for the Sissysit are coming along, should be able to begin the assembly as soon as I received your boards that must be stuck at the Canadian border and... the cinemag trafo..
Merci !
Hubert
sent 13.08.
tracking No. RR265907948RS
left my Country next day , then no more data - it seems your postal idiots are either lazy bstrds , or someone is not paying them enough...... making them idiots
ALL-IN-ONE PACKAGE TRACKING | 17TRACK
YLab - what transformer(s) are you going to use?
Click here: F5 V3 and see post #25 for some info on transformers I've measured this year.
Great thanks for the link!
I have two mono blocks using the antek as-3218. If I understand correctly Rs 20 ohms, Cs 0.01uf and Cx 0.15uf ? Is that right ?
Just received shipping notice from Cinemag, boards are waiting...
Yes! Me too!
Ok, quick test with fully warmed up amp. First thoughts were huge amount of details and sort of ”black” backround, it’s hard to descripe. I don’t have M2 around now to compare.
Speakers 6ohm nominal that falls way below 4ohm and M25 drives them without a hiccup 🙂 really good sounding amp! Volume gets higher and higher, suddenly you notice that it’s really loud and still not hurting your ears.
Yes, it definitely was worth the trouble.
so , any better speaks , in a meantime ?
so , any better speaks , in a meantime ?
Nothing too fancy, since I sold Duevel Venuses away. But I have to say that M25 seems to make even budget-speakers rock like hell! Nad Masters-series M51 as pre-amp/dac seems to pair with Babelfish quite well.
I’m aqtually tempted to build SissySit also, hopefully it’s still available later since I have my extra money going to two other projects and my usual money-hole; Benelli motorcycle.
what's important is that you have SITs in drawer
it would be never late for kit
regarding Benelli - no porn , no glory
feel free to post 158 pics in Da Pub
it would be never late for kit
regarding Benelli - no porn , no glory
feel free to post 158 pics in Da Pub
what's important is that you have SITs in drawer
it would be never late for kit
regarding Benelli - no pron , no glory
feel free to post 158 pics in Da Pub
Can you give me a hint where to get those SIT’s? I could buy them already if available anywhere.
you didn't read this thread from start ?
🙂
contact : https://www.diyaudio.com/forums/members/pras1170.html
both THF51S and 2SK182ES are proven parts , if you ask for 2 pcs with Ugs adequate for SissySIT
also watanabetomoaki on fleabay , choice is yours
what's important is that Ugs is no greater than [-3V8] with 24Vdc rail and 2A for Iq
🙂
contact : https://www.diyaudio.com/forums/members/pras1170.html
both THF51S and 2SK182ES are proven parts , if you ask for 2 pcs with Ugs adequate for SissySIT
also watanabetomoaki on fleabay , choice is yours
what's important is that Ugs is no greater than [-3V8] with 24Vdc rail and 2A for Iq
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