You can add 7805 regulator on 12V fan output or on +/-15V output for preamp.
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despite my small electronic knowledge, I thought about it....
But my toroid is 2x24vAC so with PSU it is around 35..36v...
and I red 7805 operates at max 35v....
Or maybe I should add another small transfo?
If you wire it the way Mile shows, L7805 only sees +15V input so you would be safe there but 24VAC is a little high still for the L7815 so you still need a lower voltage transformer for that circuit. It doesn't need to be high vA transformer though.
Take some magnet wire and wind it around your toroidal trafo until you get about same AC voltage as you need in DC. Then rectify and filter as usual and feed to your 7805 or 7815 etc. not for high current but Raspi should be fine.
Nice layout,
Value IC1 not 7812 for out +15 V, but 7815.
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There other errors too. I had the L7805 connected to the negative rail. Should be fixed now.
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Hi Prasi,
Your layout. I just modified it a little to add the +5v. I also adjusted the inputs and outputs to fit standard euro connectors. I built one of these to power an FX100. I wanted to use the +-15v output to power a linear pre and maybe a balanced input circuit but I'm not sure it is clean enough for the task.
As for camelator's need, I wonder if a zener shunt could bring the rails down enough to feed the L7815/L7915. Would that lower the current too much?
Your layout. I just modified it a little to add the +5v. I also adjusted the inputs and outputs to fit standard euro connectors. I built one of these to power an FX100. I wanted to use the +-15v output to power a linear pre and maybe a balanced input circuit but I'm not sure it is clean enough for the task.
As for camelator's need, I wonder if a zener shunt could bring the rails down enough to feed the L7815/L7915. Would that lower the current too much?
C4 inverted,
Connect 0 v or all gnd IC to main GND.
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A9 and AX11 (More powerful version ?)
Hi,
I've never built an Apex power amp so looking through this thread the A9 and AX11 seem to be popular so I decided to send (very soon) the Gerbers to the PCB manuf. so I can have my own.
These PCB layouts were donated freely. (see attached Layout from Sonal Kunal and Thiagomogi, thanks guys)
I just realized that my power transformer are about +/-39Vac, 300Va, I've got 4 of them and I'd like to use them of course. This 78Vct translate to about +/-53Vdc so too high for the normal A9 and AX11. Can I use these nice PCB layout and change a few components to make them work at +/-53Vdc ?
If so, what should be changed ??
If not, my solution would be to make a bipolar buffered zener regulator a la Zen Part 3 from NP.
Thanks a lot,
Eric
Hi,
I've never built an Apex power amp so looking through this thread the A9 and AX11 seem to be popular so I decided to send (very soon) the Gerbers to the PCB manuf. so I can have my own.
These PCB layouts were donated freely. (see attached Layout from Sonal Kunal and Thiagomogi, thanks guys)
I just realized that my power transformer are about +/-39Vac, 300Va, I've got 4 of them and I'd like to use them of course. This 78Vct translate to about +/-53Vdc so too high for the normal A9 and AX11. Can I use these nice PCB layout and change a few components to make them work at +/-53Vdc ?
If so, what should be changed ??
If not, my solution would be to make a bipolar buffered zener regulator a la Zen Part 3 from NP.
Thanks a lot,
Eric
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Hi Eric,
My recommendation would be to build a AX-14, as it can be supplied with +/-56VDC http://www.diyaudio.com/forums/soli...timate-fidelity-amplifier-32.html#post2294815 and you can use your trafo , no problem..
There are other amplifier's ofcourse, but Mr. Mile started the thread with AX-14🙂.
reg
Prasi
My recommendation would be to build a AX-14, as it can be supplied with +/-56VDC http://www.diyaudio.com/forums/soli...timate-fidelity-amplifier-32.html#post2294815 and you can use your trafo , no problem..
There are other amplifier's ofcourse, but Mr. Mile started the thread with AX-14🙂.
reg
Prasi
There are ofcourse Apex FX-8 and Apex FX-8 Bimo Mod amps that have become popular recently. In my opinion FX-8 is sweet!. They need 35V supply. What will the amp drive? 4 ohm or 8 ohm affair?
reg
Prasi
reg
Prasi
Thanks Prasi.
Do you know if some Gerbers file are available ?
My speakers are 4 ohm.
Mr Mile,
What models would you say work at these voltages of roughly +/-53Vdc, have Gerbers available and are strong performers so I get hooked to Apex amps ?
Many Thanks,
Eric
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For +-53V I would recommend either A33 or A23. They both have two pair of outputs so can handle the voltage.