few things - don't waste your time with WCF; I made it as option , but consensus by now is that is too much of good thing ...... interesting for Babelfish M25 , simply because of inherently much lower THD than SissySIT , so adding some sugar can be good in some circumstances
while with SissySIT , in most cases it is too much
regarding F4 - as I'm always saying - there is no comparison between amps really ...... but comparison of some other amp vs. preamp driving a F4 ...... simply because F4 is always just forwarding preamp's character , nothing more
and yes - that NP of yours ......... my Pa is eating him for breakfast , every day
NP is fun , as I heard , but Pa is much funnier
edit: luckily we had few more eyes and brains , to help with your adventure ; mine would suffice eventually , but it was faster with help of Greedy Boyz 🙂
and ....... don't waste your time with serious listening ...... just enjoy ; I know that you must (and you will ) realize the same , but now you made one of the best small amps money can buy ..... either commercially done or as DIY
while with SissySIT , in most cases it is too much
regarding F4 - as I'm always saying - there is no comparison between amps really ...... but comparison of some other amp vs. preamp driving a F4 ...... simply because F4 is always just forwarding preamp's character , nothing more
and yes - that NP of yours ......... my Pa is eating him for breakfast , every day
NP is fun , as I heard , but Pa is much funnier
edit: luckily we had few more eyes and brains , to help with your adventure ; mine would suffice eventually , but it was faster with help of Greedy Boyz 🙂
and ....... don't waste your time with serious listening ...... just enjoy ; I know that you must (and you will ) realize the same , but now you made one of the best small amps money can buy ..... either commercially done or as DIY
Last edited:
few things - don't waste your time with WCF; I made it as option , but consensus by now is that is too much of good thing ...... interesting for Babelfish M25 , simply because of inherently much lower THD than SissySIT , so adding some sugar can be good in some circumstances
while with SissySIT , in most cases it is too much
regarding F4 - as I'm always saying - there is no comparison between amps really ...... but comparison of some other amp vs. preamp driving a F4 ...... simply because F4 is always just forwarding preamp's character , nothing more
and yes - that NP of yours ......... my Pa is eating him for breakfast , every day
NP is fun , as I heard , but Pa is much funnier
edit: luckily we had few more eyes and brains , to help with your adventure ; mine would suffice eventually , but it was faster with help of Greedy Boyz 🙂
and ....... don't waste your time with serious listening ...... just enjoy ; I know that you must (and you will ) realize the same , but now you made one of the best small amps money can buy ..... either commercially done or as DIY
As always, thanks for the input.
I feel really privileged to have mono-block F4s & SissySITS both just hanging out ready to make beautiful music. Plenty of frustration in the build process, but also lots of enjoyment and learning. And I don't need a large amp, so I'll just consider that I have two of the best available...
Hi, finally some time to make an attempt to get the sissysit up.
Pcb’s are done, cinemag HQ trafo
Will re-use my two identical M2 amps as dual channel mounted monoblocks, M2 and sissysit per chassis. I shall power one channel per chassis.
Sissy question...
I have 4 Harris p9240 unused; in the M2 it was advised to use them, got them from Teabag, but I used Toshiba’s, so 4 left over, could use 2 of them.
Would they improve the amp, and if so; need to be measured for Vgs?
Pcb’s are done, cinemag HQ trafo
Will re-use my two identical M2 amps as dual channel mounted monoblocks, M2 and sissysit per chassis. I shall power one channel per chassis.
Sissy question...
I have 4 Harris p9240 unused; in the M2 it was advised to use them, got them from Teabag, but I used Toshiba’s, so 4 left over, could use 2 of them.
Would they improve the amp, and if so; need to be measured for Vgs?
o yeah , Harris welcomed
no need for any measurements ...... at least that was my experience with P Harris - they were all well more than 4V of Ugs , for I/V area of interest
no need for any measurements ...... at least that was my experience with P Harris - they were all well more than 4V of Ugs , for I/V area of interest
I have a couple of 20v 400va transformers and wanted to know if I could use them with a CRC power supply in the SissySIT? Not sure if it would be to much voltage.
it'll work for sure , if you have proper set of SITs , measured at 24V/2A , with Ugs no more than 3V7 , when hot
possibility of slight increase of R in CRC , vs. my fave value of 0R1
say two paralleled WW of 0R47 , which will give you 0R235 , then you're shooting for 420mV across , when setting Iq (1A8)
if you abandon idea of using these, from any reason , feel free to send them to OPLDF
possibility of slight increase of R in CRC , vs. my fave value of 0R1
say two paralleled WW of 0R47 , which will give you 0R235 , then you're shooting for 420mV across , when setting Iq (1A8)
if you abandon idea of using these, from any reason , feel free to send them to OPLDF
Am I the only one here waiting for the cinemag transformers to arrive?! Paid for 2 months ago and no news since ! Board are fully stuffed and waiting patiently.. 
ZM,
Thanks.
Ylab,
No your not, though I have not been wait as long. I ordered mine about 3 weeks ago.
Thanks.
Ylab,
No your not, though I have not been wait as long. I ordered mine about 3 weeks ago.
I ordered 4 cinemags in early August. I called about 2 weeks ago to see if they forgot about me, and there was something about a supplier issue with lamination material. I have one set of boards and 1 chassis ready to go, except the cinemags. I need to build up my 2nd set of boards and power supply...
I just wrote them a email and they replied to me immediately with this :
“ The laminations finally came in. They are made to our special order. We will ship very soon. Thanks for your patience.
All the best,
David “
So I guess we should have our transformer very soon! Maybe there’s just too many people ordering hpc transfo for the sissysit 😀
“ The laminations finally came in. They are made to our special order. We will ship very soon. Thanks for your patience.
All the best,
David “
So I guess we should have our transformer very soon! Maybe there’s just too many people ordering hpc transfo for the sissysit 😀
Excellent! I was just about to email them to pester about the set I ordered... thanks for the news. 😀
Instead of split washers, any objection to using nyloc nuts instead? Any experience with these? They are supposed to be good up to 120C
Nyloc nut - Wikipedia
I got my FE and OS adjusted nicely (gets really hot - #$%# hot actually or 60C) but found out later I am not supposed to have R13 because I am using Cinemag. I am taking them out now but don't expect to have damaged anything did I? FE adjusted to 20ma and 0V offset (it swings around but close enough) even with R13 in there in case you were wondering.
Nyloc nut - Wikipedia
I got my FE and OS adjusted nicely (gets really hot - #$%# hot actually or 60C) but found out later I am not supposed to have R13 because I am using Cinemag. I am taking them out now but don't expect to have damaged anything did I? FE adjusted to 20ma and 0V offset (it swings around but close enough) even with R13 in there in case you were wondering.
just snip those R13 , no need for firing up the solder station
what exactly is 60C ?
entire heatsink or parts , as hottest ?
what exactly is 60C ?
entire heatsink or parts , as hottest ?
Entire heatsink after an hour. I think the washer on the 9140 was 65C or 70C.
Heatsink too small? Need a babysitter?
Heatsink too small? Need a babysitter?
@ twitchy:
PICS PLEASE...you know the rest!
Here is one of my yesterday parcel! (and a couple more)...
The Boards are 'burning in".......NOT😎
The SP10 is a very ambitious project...just motor and platter in a new plinth...not this kitchen top mock-up. ALL electronics are in the case to the left, and the umbilical carries all power and controls. 🙂
The other one was a garage😱...I may just tidy it up soon!
PICS PLEASE...you know the rest!
Here is one of my yesterday parcel! (and a couple more)...
The Boards are 'burning in".......NOT😎
The SP10 is a very ambitious project...just motor and platter in a new plinth...not this kitchen top mock-up. ALL electronics are in the case to the left, and the umbilical carries all power and controls. 🙂
The other one was a garage😱...I may just tidy it up soon!
Attachments
Nice work and makes for a clean implementation. ZM thanks again for the work.ha, it took me at least 5yrs , to engage brain and draw them ....... ordering is trivial afterwards
How do you wire for 115vac?
