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mini A is ....... rails lower than 24 , but not much lower than 18
current lower than real Aleph (say 2A , aroundish) , but not lower than 1A
go figure .... and decide do you want mini , or proper one
or you just like to call proper one - Mini
current lower than real Aleph (say 2A , aroundish) , but not lower than 1A
go figure .... and decide do you want mini , or proper one
or you just like to call proper one - Mini
id go more along with 20V rails at 1.5 amps, remember you will need HUGE heatsinks.. Trust us.😱
Just checking, on the very fist page, it says this about the Transformer:
--The suggested rails are +-15V. It draws approximately 1A. Remember that transformer in the corner you've been trying to find a use for? The one that wasn't big enough for anything else? Smile, little orphan trannie, it's your day in the sun...
This seems to imply a 12-0-12 torrid ... ( 2X if I go dual mono )
Thus, I was thinking this:
AS-2212 - 200VA 12V Transformer - AnTek Products Corp
It's a simple change of plan to get it in 15, but I'd rather order once! which would give the 18V rails mentioned above.
Dave
--The suggested rails are +-15V. It draws approximately 1A. Remember that transformer in the corner you've been trying to find a use for? The one that wasn't big enough for anything else? Smile, little orphan trannie, it's your day in the sun...
This seems to imply a 12-0-12 torrid ... ( 2X if I go dual mono )
Thus, I was thinking this:
AS-2212 - 200VA 12V Transformer - AnTek Products Corp
It's a simple change of plan to get it in 15, but I'd rather order once! which would give the 18V rails mentioned above.
Dave
As a by the way, been reading through the chipamp.com BOM, and it seems to make sense to populate the caps at 50V and 22K uF ... If I decide to go bigger later, I will have the capacitance needed.
SLPX223M050H9P3 Cornell Dubilier - CDE | Mouser
SLPX223M050H9P3 Cornell Dubilier - CDE | Mouser
sure, might as well. and get the matching tall (2") to220 sinks for the rectifiers if you have any intention of experimenting with high current.
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A matching circuit
Dug around on the Pass site and found this:
Did some more reading, and found this to help translate this to a proto board
bought a bunch of bits and bobs, looked up the data sheet to get GDS as the pin order with the chip facing out, put the parts on a proto-board, and added the traces.
Does this look right?
Before I get out the soldering iron, any thoughts appreciated.
Dave
Dug around on the Pass site and found this:
Did some more reading, and found this to help translate this to a proto board
bought a bunch of bits and bobs, looked up the data sheet to get GDS as the pin order with the chip facing out, put the parts on a proto-board, and added the traces.
Does this look right?
Before I get out the soldering iron, any thoughts appreciated.
Dave
Your proto board has 13.8v going to both resistors then on from each resistor to the source of each mosfet which isnt the same as the schematic. Of course youll need a heatsink and a large dc blocking cap on the output. I dont think this will work for you though. Its really a simplified schematic showing only the important bits the author is talking about at the time.
Dave, are you trying to match
the input irf9610 devices?
If so, the current with a 10 ohm
resistor is far too high. They
operate in the 10mA range in the
front end so something in the 1k ohm
range is more appropriate.
Dennis
the input irf9610 devices?
If so, the current with a 10 ohm
resistor is far too high. They
operate in the 10mA range in the
front end so something in the 1k ohm
range is more appropriate.
Dennis
Thanks Dennis;
What I am trying to do is test 2X IRF9610 at one go. I would guess thats why my layout does not match the pass schematic.
So, replace the resistor, easy enough.
Next post up, its mentioned that "of course youll need a heatsink and a large dc blocking cap"
Is there general agreement on the cap, and if so, values and location in the modified schematic.
Thanks for the help.
Dave
Hey Dave, how's the mosfet matching coming? I'm having trouble finding any kind of source for matched IRF9610s online. Drop me a PM if you have extras and maybe we can work something out.
After a long time thinking, I have decided to go ahead and build the mini-aleph (quad channels) for some active speakers. Been using TPA3116 classD amps up until now. I have a SE tube amp (GTA SE40) and have always wanted to have an aleph. Just ordered brianGTs boards from chipamp.
I don't think I will need more than the 10watts of the mini-aleph since my drivers are 4ohms and rather efficient so I am hoping to build the mini version. I also really like the idea of a single output transistor and no need to match the output mosfets.
But I have a question about the rail voltage. Would 22v be too much for a single output MOSFET (IRFP240 or IRFP140)? I am debating between using IRFP240 or IRFP140 and will probably try both. I will also be building with an outboard power supply so that I can try switching-mode, linear and battery PS over time. I currently have a meanwell NES-150-24 (24v) SMPS and would like to reuse it (buy a second to get the positive and negative rail voltages). This meanwell SMPS is rated for 24v but can be adjusted slightly (mine can go down to 22.2v). If 22v is pushing too far for a single IRFP240 or IRFP140, then I will get a new pair of RS-150-15 and run them at 16.5v.
thanks in advance for any help.
I don't think I will need more than the 10watts of the mini-aleph since my drivers are 4ohms and rather efficient so I am hoping to build the mini version. I also really like the idea of a single output transistor and no need to match the output mosfets.
But I have a question about the rail voltage. Would 22v be too much for a single output MOSFET (IRFP240 or IRFP140)? I am debating between using IRFP240 or IRFP140 and will probably try both. I will also be building with an outboard power supply so that I can try switching-mode, linear and battery PS over time. I currently have a meanwell NES-150-24 (24v) SMPS and would like to reuse it (buy a second to get the positive and negative rail voltages). This meanwell SMPS is rated for 24v but can be adjusted slightly (mine can go down to 22.2v). If 22v is pushing too far for a single IRFP240 or IRFP140, then I will get a new pair of RS-150-15 and run them at 16.5v.
thanks in advance for any help.
for 4 ohms speaks you need amps , not volts
so , for 10W , I wouldn't go bellow 1A Iq , while less than 15Vfor rails isn't for recommendation
in practice , proper xformer with 12Vac secondaries , plus hefty cap bank , will give you that
so , for 10W , I wouldn't go bellow 1A Iq , while less than 15Vfor rails isn't for recommendation
in practice , proper xformer with 12Vac secondaries , plus hefty cap bank , will give you that
Hi
I want to do an Aleph M amplifier. I bought the pcb on KK-PCB and he tell that a heatsinks of at least 0.4c/w per channel is necessary.
My question is: do you think that this heatsinks is enough Dissipateur profilé peigne 661 - Profilés coupés ? or this http://www.selectronic.fr/radiateur-profile-peigne-663.html.:confused:
I known that there is a little difference in rth (0.4c/w vs 0.35c/w) but the price is double.
Thanks a lot for your answer and sorry for my bad english.
I want to do an Aleph M amplifier. I bought the pcb on KK-PCB and he tell that a heatsinks of at least 0.4c/w per channel is necessary.
My question is: do you think that this heatsinks is enough Dissipateur profilé peigne 661 - Profilés coupés ? or this http://www.selectronic.fr/radiateur-profile-peigne-663.html.:confused:
I known that there is a little difference in rth (0.4c/w vs 0.35c/w) but the price is double.
Thanks a lot for your answer and sorry for my bad english.