I am using 0.5R resistors in CRC filter in power supply, 22kuf-0.5R-22kuf and in the future want to use 66kuf-0.5R-66kuf and I guess I will have higher rail voltage, maybe I will try using 1R instead 0.5R in the filter so I could raise the bias a little 200-300ma per fet but I don`t know if that does woth it because I am already satisfied with output power and if I raise the bias more I will push the fets at their extremes and don`t want that
60Wpc peak or average?
60Wpc peak or average?
with my dmm set on Vac I can read at output 10V peaks with speaker connected(3.5ohm) and without my ear to sense any distortion but I guess there is a little bit ...
Then I will leave it this way regarding bias and and rail voltage
It will stay on my work bench for few weeks for test(ACCG) and waiting for the cases to be ready
For the moment I don't use any grease between mosfets isolator and heatsink I only polished the region where fets came in contact with heatsink with 1000 abrasive paper so these will make better thermal contact and the surface is plane
It will stay on my work bench for few weeks for test(ACCG) and waiting for the cases to be ready
For the moment I don't use any grease between mosfets isolator and heatsink I only polished the region where fets came in contact with heatsink with 1000 abrasive paper so these will make better thermal contact and the surface is plane
I have decoupled R24 from the circuit, this is really a big improvement in sound for those who want lower output power(half the original aleph power maybe less).I guess I am going to use a switch between C3 and R24 with 2x 10-15cm long wire.Will there be any problems if the wire is so long?(hope not) and one more question can I operate the switch when the amp is powered up?
I really like this amp because is so modable and very good sounding, compared it to JLH 2003 prototype which i built last summer and they are sounding almost the same but with Aleph CCS enabled, when i disconnect R24 the JLH doesn`t stand a chance(the JLH is built with ordinary recovered parts(no Dale,no Panasonic caps))
The las thing(for the moment) I want to try is to short out C1 from circuit to see sound improvements
I really like this amp because is so modable and very good sounding, compared it to JLH 2003 prototype which i built last summer and they are sounding almost the same but with Aleph CCS enabled, when i disconnect R24 the JLH doesn`t stand a chance(the JLH is built with ordinary recovered parts(no Dale,no Panasonic caps))
The las thing(for the moment) I want to try is to short out C1 from circuit to see sound improvements
yes I have made the same experience some time ago...🙂
and when you do not need so much power only a few Watt, give the "Simple SIT" from Mike ........later........a chance!
http://www.diyaudio.com/forums/diyaudio-com-articles/202480-l-amp-simple-sit-amp-part-deux.html
😀😀
Hi, I'm new here and in the middle of tweaking my aleph J with 2sk1530, what is exactly 'decoupling R24'? how it's done?
thanks
you simply remove R24 from the circuit, this improves sound quality but lowers the power.give it a try!
some like it , some do not
with removal of that resistor , Aleph CCS became plain , un-modulated , CCS
with removal of that resistor , Aleph CCS became plain , un-modulated , CCS
It means that C3 is non functional, worth trying I think
and ZM, any other changes required with 2SK1530 when R24 is removed? I have biased the SK's at 0.5A
thanks (just get back from fun reading the papa 'clone' casing)
and ZM, any other changes required with 2SK1530 when R24 is removed? I have biased the SK's at 0.5A
thanks (just get back from fun reading the papa 'clone' casing)
pull out C3 or R24 , whatever ..... same as that you pulled them both
0,5A - that's some sissy amp
, presuming that you have just 2 output pairs ........ = 1A Iqno other changes
do you have any ideea where some of these K1530 can be found at a reasonable price and original?
240 are good enough
or be a cheapskate , with better sound (sic!) and use just one pair of IRFP150
see Babelfish J
or be a cheapskate , with better sound (sic!) and use just one pair of IRFP150
see Babelfish J