no need for overengineering here - Sissy is using SIT with less than 50W of dissipation and it's proven that SIT is happy even if having crummy silpad, bloody worse than mica+goop
however, in case of higher (possible) level of dissipation per part ( plenty of amps made recently, Singing Bush and Babelfish XA252 SIT being just two of them),using better solution is advisable ....... what's already proven is Keratherm and , again, mica+goop
I think that every specific solution must be checked in proper way - screws must be tightened to 1.3Nm (figure advised for pucks, so pretty much logical to SIT case too), which - by my understanding - is also ensuring long time stability of torque, thinking of screw-split washer - and everything else being in game
so- pad, even if soft, must behave with 1.3Nm
Moi, Old Fart, either mica+goop - or Keratherm ; everything else is too much thinking
however, in case of higher (possible) level of dissipation per part ( plenty of amps made recently, Singing Bush and Babelfish XA252 SIT being just two of them),using better solution is advisable ....... what's already proven is Keratherm and , again, mica+goop
I think that every specific solution must be checked in proper way - screws must be tightened to 1.3Nm (figure advised for pucks, so pretty much logical to SIT case too), which - by my understanding - is also ensuring long time stability of torque, thinking of screw-split washer - and everything else being in game
so- pad, even if soft, must behave with 1.3Nm
Moi, Old Fart, either mica+goop - or Keratherm ; everything else is too much thinking
Thanks for keeping us grounded ZM.
1.3Nm isn't that much torque so I think piercing a pad is unlikely unless you trap some sort of foreign object in the interface. Fortunately I do my own bike maintenance so have a small torque wrench for small metric thread nuts/bolts.
1.3Nm isn't that much torque so I think piercing a pad is unlikely unless you trap some sort of foreign object in the interface. Fortunately I do my own bike maintenance so have a small torque wrench for small metric thread nuts/bolts.
I wrote that somewhere - recently I bought two of them , did set one to 0.9Nm (M3) and second to 1.3Nm (M4) ....... and now I have even less to think
though, ZM Cheapskate, with some patience involved in search - paid 45E for both, instead 80-90 each, which is regular price everywhere
Alixprs is good place, but postage to my neck of wood is outrageous , so no go for me ; bough both on local add site
though, ZM Cheapskate, with some patience involved in search - paid 45E for both, instead 80-90 each, which is regular price everywhere
Alixprs is good place, but postage to my neck of wood is outrageous , so no go for me ; bough both on local add site
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well, that is in the end going to be extremelly Fugly!
while I sent abroad more than 2/3 of all recent amp kits, I'm just about ready to receive bunch of LT3092, so I can complete shipment, and invest some time in next batch of new amps
Might that next one be the.....
"Babelfish XA252 / Babelfish XA252 SIT / Babelfish XA252 SET" by any chance?
Pretty please! 🙂
"Babelfish XA252 / Babelfish XA252 SIT / Babelfish XA252 SET" by any chance?
Pretty please! 🙂
maybe, maybe not 
I forgot that - of amps with xformer gain , I have one more - last one, called Il Penitente
I forgot that - of amps with xformer gain , I have one more - last one, called Il Penitente
Is there something you wish to confess that has influenced that name...
Attachments
well, that is in the end going to be extremelly Fugly!
while I sent abroad more than 2/3 of all recent amp kits, I'm just about ready to receive bunch of LT3092, so I can complete shipment, and invest some time in next batch of new amps
Hey ZM, seeing this made me think to check, did you see my email about an order? If not drop me a message and I'll let you know what it was 🙂
Nautibuoy if those are XRK971 second generation speaker protection he recommended mounting them with plastic standoffs because he did nor isolate the mounting holes. First ones were ok. I have both and they work well. I just placed order for SitR3 watching with interest. Would like to power with SMPS, ZM what is the max voltage for good performance.
Thanks
Bill
Thanks
Bill
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Yes, thanks Bill. I'm aware and I'll be using nylon standoffs for the final assembly - the picture was taken when I was drilling/checking the chassis.
I'm building with a conventional CRC power supply but did wonder about using SMPSs so will be interested in how this works out.
I considered ordering a couple of these, customised for the correct SissySIT voltages.
SMPS500R +-45V 230V 500W Switch Mode Power Supply | Hifime Audio
SMPS sissy sitr3
This one manufacturer recommended by XRK
SMPS500-CLA – MicroAudio
They are pricey and I would prefer 300va X 2 , I don’t think a single 500va would be enough for 2 channels. I will probably use this amp to power high frequency of bi- amped setup so don’t need max power but should still build it for non bi-amp use for versatility. They said when time available they could try to build one up for 18V to test. That is why I asked ZM about voltage, they do make a 25 V one already.
Bill
This one manufacturer recommended by XRK
SMPS500-CLA – MicroAudio
They are pricey and I would prefer 300va X 2 , I don’t think a single 500va would be enough for 2 channels. I will probably use this amp to power high frequency of bi- amped setup so don’t need max power but should still build it for non bi-amp use for versatility. They said when time available they could try to build one up for 18V to test. That is why I asked ZM about voltage, they do make a 25 V one already.
Bill