Note that the measurements and specifications in Nelson's article were probably based on his suggested 50V power supply. The maximum output voltage will be lower and distortion may be higher at lower power supply voltages.
That's a great point, Ben. Using a 50V power supply may bring more improvements in the FE sound.
I'll have to try that.
I'll have to try that.
Ben Mah,
How much current does your implementation of the circuit require?
I want to try a lclc filter for the power supply.
Thanks and take care,
How much current does your implementation of the circuit require?
I want to try a lclc filter for the power supply.
Thanks and take care,
anyone to share their comments/experience with this new front end for their aca mini and aca monoblocks?
I used the original kit boards with no fancy parts with a VRDN board supplying +/-18V and powering Neal Brock's ACA Redux amps. I cut the heatsinks a little short on the VRDN board and then this lot fits nicely into a small 1U Galaxy chassis.
Streaming from youtube with a JDS Labs Atom+ DAC it sounded really good. To be fair I do not have well calibrated ears, but I liked it, so I'm not sure there is a lot more to add.
Streaming from youtube with a JDS Labs Atom+ DAC it sounded really good. To be fair I do not have well calibrated ears, but I liked it, so I'm not sure there is a lot more to add.
Attachments
Pushing it, but I expect a 70v limit...My power supply is around 62V, and I measured 17mA per channel.

Mr. Pass, could you tell us the rough current of the first and second stage CCS?
A little under 3 ma and 9 ma. Approximate, but not at all critical.
I measured 1.4V which translated to 4.2mA. It's close enough since Nelson has said that it is not at all critical. So no worries. 🙂
Hi
Could someone who has received the latest PCB version tell me the dimensions.
I’m already working on the enclosure so just want to make sure 2 new pcb will fit 😀
Thanks
Eric
Could someone who has received the latest PCB version tell me the dimensions.
I’m already working on the enclosure so just want to make sure 2 new pcb will fit 😀
Thanks
Eric
I measured 1.4V which translated to 4.2mA. It's close enough since Nelson has said that it is not at all critical.
Now my board quite perfect, 1.4V across 332R, 0.9V across 100R, offset 35mV with original value.I measured 1.4V which translated to 4.2mA. It's close enough since Nelson has said that it is not at all critical. So no worries. 🙂
My FE2023 build with remote control is ready to fire up and testing now.
The idea is to use an old IR control lying around for input selection and volume control.
At first this project was planned to control an Iron Pre.
Some specs for this I have posted two months ago in Iron Pre builders thread.
But why not to use it in FE2023? I asked myself... So thought, so done and
I made my mind up to take a chance on a SMPS and found a tiny MeanWell with single 48 V 30 VA.
Why worry about 16 MHz from arduino, 150 kHz from step-down DC-DC converters
and 65 kHz from SMPS? Those high frequencies in my age are really unnoticeable...
The first quick connect to REW w/o load looks very nice and I'm singing now:
...I know what I like and I like what I know...Bum-de-dum, de-dum...
If anyone is interested in this project I will provide all data to make it real with Gerber, wiring plan, software and support.
Last but not least many, many thanks to Pa for this excellent and fantastic circuit with KISS
and the best quality kits from the store.
The idea is to use an old IR control lying around for input selection and volume control.
At first this project was planned to control an Iron Pre.
Some specs for this I have posted two months ago in Iron Pre builders thread.
But why not to use it in FE2023? I asked myself... So thought, so done and
I made my mind up to take a chance on a SMPS and found a tiny MeanWell with single 48 V 30 VA.
Why worry about 16 MHz from arduino, 150 kHz from step-down DC-DC converters
and 65 kHz from SMPS? Those high frequencies in my age are really unnoticeable...

The first quick connect to REW w/o load looks very nice and I'm singing now:
...I know what I like and I like what I know...Bum-de-dum, de-dum...
If anyone is interested in this project I will provide all data to make it real with Gerber, wiring plan, software and support.
Last but not least many, many thanks to Pa for this excellent and fantastic circuit with KISS
and the best quality kits from the store.

Attachments
If anyone is interested in this project I will provide all data to make it real with Gerber, wiring plan, software and support.
More, please. The DC-DC converter and the Arduino and display boards. Are they discussed elsewhere on this site?
More, please. The DC-DC converter and the Arduino and display boards. Are they discussed elsewhere on this site?
If anyone is interested in this project I will provide all data to make it real with Gerber, wiring plan, software and support.
Interested here, thanks
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The remote control and all its components are working in digital domain.
So, I don't think, that this thread is the right place to discuss their properties.
You buy these for a few $ or €, solder on PCB, provide +12 V and upload the software. That's all.
The idea and BOM was posted in "Iron Pre Essentials Kits For The DIYA Store- Register Your Interest"
at #336 and #344.
Send me a PM, please if you need more details and want to build it. I'm trying to help.
So, I don't think, that this thread is the right place to discuss their properties.
You buy these for a few $ or €, solder on PCB, provide +12 V and upload the software. That's all.
The idea and BOM was posted in "Iron Pre Essentials Kits For The DIYA Store- Register Your Interest"
at #336 and #344.
Send me a PM, please if you need more details and want to build it. I'm trying to help.

Hi
When I’ll be ordering my kit, I’m planning to have a gain switch to go from Low to High 10/20db therefore I’ll need a higher voltage power supply to do this properly.
Would the following SMPS be OK for this at 48Vdc, 0.5A ?
My goal would be to be able to drive a F4 clone.
I’m assuming it’s a quiet model since it’s the same series as the one used in the ACA Mini kit.
Thanks,
Er
Power supply
When I’ll be ordering my kit, I’m planning to have a gain switch to go from Low to High 10/20db therefore I’ll need a higher voltage power supply to do this properly.
Would the following SMPS be OK for this at 48Vdc, 0.5A ?
My goal would be to be able to drive a F4 clone.
I’m assuming it’s a quiet model since it’s the same series as the one used in the ACA Mini kit.
Thanks,
Er
Power supply
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