🙂) hope you`re kidding with the second one cause the first appears as blank on my screen 🙂) what were you saying ? 😱
or you can make one by your self - there is pdf of pcb somewhere in start of Babelfish J thread
IXYS has lesser Ciss
now I use irfp240 but got this huge mosfets and was wondering if there will be any sonical improvement if I use them 😀
I just read the topic from the link you gave me last night and saw that i have to paralel input j`s to drive properly the 280A n mos.In the meantime an idea just came up in my head...and that is to sell the IXYS and buy with the money 4 pairs of power j`s.wouldn`t that be sonically better?(retoric question 🙂) )
now I use irfp240 but got this huge mosfets and was wondering if there will be any sonical improvement if I use them 😀
I just read the topic from the link you gave me last night and saw that i have to paralel input j`s to drive properly the 280A n mos.In the meantime an idea just came up in my head...and that is to sell the IXYS and buy with the money 4 pairs of power j`s.wouldn`t that be sonically better?(retoric question 🙂) )
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if ya mean on Semisouths .......... rhetoric answer to rhetoric question is - yes
all you need is proper schm .....
search for 6L6's thread about Aleph J with SS
Papa gave him back'o'napkin sch , along with input Jfets and output SS
all you need is proper schm .....
search for 6L6's thread about Aleph J with SS
Papa gave him back'o'napkin sch , along with input Jfets and output SS
Thx ZM for the hints and for your help.I`ll go out to get a beer now...or two don`t know exactly but probably two, one for me and one for you 😀
Cy
Cy
Well Jacco (and others), I finally got my new toy, a Fluke 179 with original Fluke 80BK-A probe, and have checked the temperature of my amps. I did not remove the covers to check Mosfet temperature; just checked the heatsinks.
The Aleph 2 monoblocks (Hifi2000/Modushop 4U 400mm enclosures) have been switched on for about 5 hours and I do not think they will get any hotter. Ambient temperature in my study is now 26.4 (yes, they do produce a lot of heat) and the heatsinks are at 56.7, i.e. aprox. 30 degrees above ambient.
Bias is set by the originally specified values of the circuit, so dissipation should be close to the original. Dissipation is actually probably a little higher than the original as I have 2 x 40V AC secondaries where I think the original had 2 x 37V AC secondaries.
Assuming dissipation is 300W, the measurerd rise of 30 degrees is about 0.1C/W.
According to the Modushop specs the heatsinks (4 per enclosure) are rated at 0.38C/W each. This is close to the results I have measured.
Which reminds me that I need to get off my duff and finish that amp! It is my goal to have it complete by this year's Burning Amp.
yes thats close🙂
i also used 2x40V sec for aleph2. and they had 270W dissipation on the sinks. all values as schematic.
i also used 2x40V sec for aleph2. and they had 270W dissipation on the sinks. all values as schematic.
hello, it`s me again 😀
i`m wondering which rectifiers are best for aleph fast soft recovery or schottky.got both on hand and don`t know which to choose ...
i`m wondering which rectifiers are best for aleph fast soft recovery or schottky.got both on hand and don`t know which to choose ...
the diodes i was talking about are these http://ixdev.ixys.com/DataSheet/DSEP2x31-12A.pdf . the schottky ones are few and cant use them.
pcb check
a while ago i started to build this amp.
after collecting the parts, winding a toroid and making a board for the PSU caps it's time for the real amp.
I tried to design a PCB (much alike nelson's board) which will fit nicely on my heat-sinks
But since i dont have experience in building amps i would like to get some feedback on the PCB design.
Will this design work, or am i making some (stupid) mistakes here.
notes on the design:
-It's a single layer design; the routes on the "top" layer are jumper wires.
-The power resistors are smaller than on this pcb design (couldnt find the right symbol)
-the shape and dimensions of the board are based on heat-sinks i allready have
a while ago i started to build this amp.
after collecting the parts, winding a toroid and making a board for the PSU caps it's time for the real amp.
I tried to design a PCB (much alike nelson's board) which will fit nicely on my heat-sinks
But since i dont have experience in building amps i would like to get some feedback on the PCB design.
Will this design work, or am i making some (stupid) mistakes here.
notes on the design:
-It's a single layer design; the routes on the "top" layer are jumper wires.
-The power resistors are smaller than on this pcb design (couldnt find the right symbol)
-the shape and dimensions of the board are based on heat-sinks i allready have