@sbelyo, Here's a link to one of my ITX build, using a PurePi and a VIML3 and Tone 2 board (DIY version). I did have some software issues that I could never resolve so I'm working on version 2, that will be based on an RPi and HDMI screen - instead of non-standard hardware. But, you can get an idea how such a DAC implementation can take shape.
Here's the chassis pictures. I ordered two of them. The transformers will sit in an identical chassis either underneath or to the right once placed in my stack. The chassis is alodine coated for emi and corrosion protection then powder coated gray. It measures 17"x14"x4" . The gray boxes will hold a pair of super caps with UCPure's mounted on top. The empty spot in the upper right is where the StationPi will be. I have a slick idea to recess mount some speaker cabinet spikes as feet. I'll try to work on those tomorrow. This should should give you a rough idea of the layout.
Excuse the mess! I'm still several weeks out from completing a new workshop. All my stuff is in one corner of my garage on my old work table
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@sbelyo This a well planned project looks really good it s not easy to plan a complete closed system, but looks like you are on a good start . Checkout my power supply for the D11 I did a bit over a year ago for some ideas specially the snubber circuit that will soften the huge spark that happens when you power multiple transformers at once, and trigger in and out and timer, fuses....There are some nice helpful schematics. that you may find handy
Thanks @Gabster 2000, I was wondering about the current draw. I will have 4 9Volt 50VA transformers turning on so that's a great point. I'll take a look at what you did
@sbelyo I had mine for years in a drawer anything 12v dc relay bigger then the flimsy blue ones would be better
Mine is similar to this one from mouser but I don’t remember paying that much for it
https://www.mouser.ca/ProductDetail/TE-Connectivity/KUMP-11D18-12?qs=q/P0zrNg69y/JKcJhWm1%2BA==
Mine is similar to this one from mouser but I don’t remember paying that much for it
https://www.mouser.ca/ProductDetail/TE-Connectivity/KUMP-11D18-12?qs=q/P0zrNg69y/JKcJhWm1%2BA==
@Gabster 2000 great video as always! I have a few questions about this circuit
What is the purpose of the relay here? As a noob I did some research and it seems a relay is simply another form of a switch. Is the goal here to soften the inrush current of the toroid transformers? In which case we would need a soft-start circuit?
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@NeoTheOne
A relay functions like a switch that you can control using low voltage, such as 12V or 5V, to switch high voltage like 120V or 240V. Using a switch instead would mean losing the ability to use triggers, inputs, and timer functions since you’d have to physically turn it on and off. The flip-flop relay handles the switching, much like high-end commercial products with a single on/off button, while cheaper ones use a switch.
The big relay can handle more current and is more reliable it is triggered by the small flip flop relay
The simple snubber circuit reduces the spark that occurs when three transformers have a huge spark at startup, which can damage the relay or even a good switch. (I have seen a lot of burnt switches). You may have seen a spark when plugging in certain appliances. When a switch or relay is rated for 15 amps, it doesn’t take into account the initial spark, which can be far greater than that.
I have mine working for a 1.5 years reliably so it has been tested.
Hope that helps
A relay functions like a switch that you can control using low voltage, such as 12V or 5V, to switch high voltage like 120V or 240V. Using a switch instead would mean losing the ability to use triggers, inputs, and timer functions since you’d have to physically turn it on and off. The flip-flop relay handles the switching, much like high-end commercial products with a single on/off button, while cheaper ones use a switch.
The big relay can handle more current and is more reliable it is triggered by the small flip flop relay
The simple snubber circuit reduces the spark that occurs when three transformers have a huge spark at startup, which can damage the relay or even a good switch. (I have seen a lot of burnt switches). You may have seen a spark when plugging in certain appliances. When a switch or relay is rated for 15 amps, it doesn’t take into account the initial spark, which can be far greater than that.
I have mine working for a 1.5 years reliably so it has been tested.
Hope that helps
Yes its just a soft start to suppress the voltage transient at power on. Not really required in trafos this small but a nice touch. Why didn't you just put a softstart pcb with thermistors in there? Loads of them on places like eBay. I put this one in my power conditioner, that has 2400w of transformers and reliably blows switches every time you turn it on without one of these.
https://www.ebay.com/itm/274321352951
https://www.ebay.com/itm/274321352951
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@Jaytor
Jaytor,
I apologize for intruding. I have been trying to reach you for assistance on building my first Preamp. I'm smitten with your Fully Balanced DCG-3. I've ordered 2x board and kits from Tea-Bag as well as the volume / input section from Khozmo. I placed the order for the Slimline 2U and Galaxy chasis from Modushop with customizations, which brings me to my question.
Do you have a dwg I could use for the chasis milling/drilling placement of the DCG-3 Balanced Preamp. My CAD skills are subpar and I want to get the front OLED screen placement and rear panel drilled correctly on my first try.
I'm also curious if you use an inner baseplate for the 2U/350 or mounted through the chasis floor (Grounding loops?). Lastly, are there other chasis inner accessories I should be purchasing that will be necessary for the build.
I hope you don't mind that I'm literally copying your build and that you subscribe to the "highest form of flattery" philosophy.
I'm including my email in case you agree to share a dwg file with me.
Thank you,
Matthew
Matthew@TexasLandMaps.com
Jaytor,
I apologize for intruding. I have been trying to reach you for assistance on building my first Preamp. I'm smitten with your Fully Balanced DCG-3. I've ordered 2x board and kits from Tea-Bag as well as the volume / input section from Khozmo. I placed the order for the Slimline 2U and Galaxy chasis from Modushop with customizations, which brings me to my question.
Do you have a dwg I could use for the chasis milling/drilling placement of the DCG-3 Balanced Preamp. My CAD skills are subpar and I want to get the front OLED screen placement and rear panel drilled correctly on my first try.
I'm also curious if you use an inner baseplate for the 2U/350 or mounted through the chasis floor (Grounding loops?). Lastly, are there other chasis inner accessories I should be purchasing that will be necessary for the build.
I hope you don't mind that I'm literally copying your build and that you subscribe to the "highest form of flattery" philosophy.
I'm including my email in case you agree to share a dwg file with me.
Thank you,
Matthew
Matthew@TexasLandMaps.com
@Gabster 2000, @NeoTheOne
I understand the circuitry with the relays to switch on and off the pre-amp, amp and best DAC in the world. However, when I see the movie on YT, when you switch off, the PI doesn't do a proper shutdown.
I use Volumio and the GPIO buttons and GPIO Control plugins to switch off the PI with proper shutdown. You can also use this this to power controll other equipment.
Volumio has an auto power off timer.
https://community.volumio.com/t/adding-power-switch-to-volumio/66423/3
I took the info from colino.net and modified this information for Volumio. And it works perfectly.
Another question, I recently watched your movie about the new UcPure Quad by Ian Canada. Could it be used to create a + & - 5V power supply?
And your movies are a real source of inspiration, I really love them.
I understand the circuitry with the relays to switch on and off the pre-amp, amp and best DAC in the world. However, when I see the movie on YT, when you switch off, the PI doesn't do a proper shutdown.
I use Volumio and the GPIO buttons and GPIO Control plugins to switch off the PI with proper shutdown. You can also use this this to power controll other equipment.
Volumio has an auto power off timer.
https://community.volumio.com/t/adding-power-switch-to-volumio/66423/3
I took the info from colino.net and modified this information for Volumio. And it works perfectly.
Another question, I recently watched your movie about the new UcPure Quad by Ian Canada. Could it be used to create a + & - 5V power supply?
And your movies are a real source of inspiration, I really love them.