Paul, what would be the best strategy for introducing USB-C PD from your experience?
Using some powerful external 24V power supply or embedding LED power supply?
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Paul, what would be the best strategy for introducing USB-C PD from your experience?
Using some powerful external 24V power supply or embedding LED power supply?
Quote: “what would be the best strategy for introducing USB-C PD from your experience?”
I don’t know.
Lots of builders of these DIY monitors have avoided USB-C PD powering from the monitor.
A Mac is a high cost device, and too important to use connected to an unwarranted charging device.
However lots of people have done so successfully with only a single hearsay report of damage to a Mac AFAIK.
I’ve used a high quality Thunderbolt 3 dock between the display and a laptop with the dock providing the PD power.
The video boards need about 72 watts of maximum power - about 24V at 3A.
PD power takes additionally about 5A more, so you need at least a 24V 200W PSU.
That‘s probably generates too much heat to put inside the iMac housing unless you install a fan and ducting to exhaust the hot air out of the case.
Several builders have done this very well, 🙂 but it’s quite a lot of work 🙁.
@webhdx #466
Me #489
@Aiwi #822
One advantage of putting the PSU internally is that it is connected by Apple’s Electromagnetic shielding circuit in the mains socket of the iMac.
Some of the cheaper PSUs available are quite electromagnetically noisy and so filtering their power input can stop the connected Mac having Bluetooth problems.
I don’t know.
Lots of builders of these DIY monitors have avoided USB-C PD powering from the monitor.
A Mac is a high cost device, and too important to use connected to an unwarranted charging device.
However lots of people have done so successfully with only a single hearsay report of damage to a Mac AFAIK.
I’ve used a high quality Thunderbolt 3 dock between the display and a laptop with the dock providing the PD power.
The video boards need about 72 watts of maximum power - about 24V at 3A.
PD power takes additionally about 5A more, so you need at least a 24V 200W PSU.
That‘s probably generates too much heat to put inside the iMac housing unless you install a fan and ducting to exhaust the hot air out of the case.
Several builders have done this very well, 🙂 but it’s quite a lot of work 🙁.
@webhdx #466
Me #489
@Aiwi #822
One advantage of putting the PSU internally is that it is connected by Apple’s Electromagnetic shielding circuit in the mains socket of the iMac.
Some of the cheaper PSUs available are quite electromagnetically noisy and so filtering their power input can stop the connected Mac having Bluetooth problems.
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Thanks a lot Paul.
Just to confirm first: can I surely use the 24V PSU?
I’m unable to find any technical specs re accepted voltage. And my seller only mentioned the 12V ones.
I still tend to increase my current 12V6A, as just panel draws about 66W at full brightness per my measurements, without any additional IO.
Very close to the limit.
But I’m unable to find any appealing external PSU capable of higher amperage at this voltage.
Taking pros and cons into account, I tend to use an external one. Not sure I can achieve a qualitative internal packaging, seeing the work that you attached.
This seller specifies a 24v PSU:
stonetaskin.com
StoneTaskin JRY-W9CUHD-AA1 5K Driver Board For iMac 27 inches A1219 A2
To create a good consumer experience, please confirm your LCD/LED Screen part number before ordering. If you're a wholesale/distributor in your country please contact us for a better price and the best logistic options Please feel free to ask any questions about the product Every order is...
Right, thank you.This seller specifies a 24v PSU:
StoneTaskin JRY-W9CUHD-AA1 5K Driver Board For iMac 27 inches A1219 A2
To create a good consumer experience, please confirm your LCD/LED Screen part number before ordering. If you're a wholesale/distributor in your country please contact us for a better price and the best logistic options Please feel free to ask any questions about the product Every order is...
I wasn’t so sure about this one, as it only mentions 24V in the USB-C PD section (or I’m missing the general specs).
And I’ve got no response over their live chat.
Appreciate your confirmation. I’ll purchase 24V one to give it a try.
Hopefully it won’t be getting as hot as my current one
Hi, I ordered the same cross over kit as your post above for my iMac speakers for my late 2015 27 inch iMac. I’ve also got the same R1811 V4 board. Before I hook it up, just wanted to ask a couple of simple questions if you don’t mind
1. Does it matter which of the cross over ”units” that I attach to the iMacs speakers (ie is one for the right speaker and one for the left speaker? Or, they’re interchangeable?
2. Is there a specific way the cross over connector for each unit plug into the iMac’s speaker that I need to be aware of?
I’ve attached a picture of my iMac. I haven’t connected or mounted of it as of yet.
Thanks in advance!
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I have exactly the same setup.Hi, I ordered the same cross over kit as your post above for my iMac speakers for my late 2015 27 inch iMac. I’ve also got the same R1811 V4 board. Before I hook it up, just wanted to ask a couple of simple questions if you don’t mind
1. Does it matter which of the cross over ”units” that I attach to the iMacs speakers (ie is one for the right speaker and one for the left speaker? Or, they’re interchangeable?
2. Is there a specific way the cross over connector for each unit plug into the iMac’s speaker that I need to be aware of?
1. Pinout is L+ L- R- R+, top to bottom. Correct crossover location on your photo.
2. I had to connect one crossover with reversed polarisation (switch + -),right speaker, to have the sound in phase.
This was discovered by PaulD-UK. The polarisation on the R1811 card is labeled wrong.
test sound output to speakers:
What does In Phase & Out of Phase Sound Like, HiFi...
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There are always extra bits to consider, it seems
With the JRY board, the USB ports only work via the type-C port. Which I wasn't aware.
I guess it's common but never tried to make it work before.
Also, it doesn't seem to be possible to disable PD in the menu.
This means to I'll have to use a juicy internal PSU (leaning towards the iMac one as discussed recently) + fans. Probably, I'll follow this guide, as I have access to the Taobao as well.
Additionally, on the subject above, the JRY board seems to have the correct polarity for the speaker connector printed.
Checked my connection with the multimeter.
Lastly, if someone will ever wonder, Apple uses CM3*7*9 screws to mount the speakers. Unfortunately, I made a mistake myself first and tried to screw a *9* one instead which just got and so one of the speakers is partially 3M'ed instead
I decided to buy all iMac parts separately instead of getting a complete machine as a starting point. Screws, unsurprisingly, became one of the hardest pieces to find.
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Yeah - for how much people are willing to pay, and the shipping logistics, it's not worth a seller's time to ebay them for the tiny profit. I have a ziploc of screws I took out of my iMac sitting along with the speakers, power supply board, and memory SO-DIMMs. Only thing I was able to profitably re-sell was the main board, and that after 3 price drops.
Thanks for this! I saw your posts along with PaulD-UK back in November but didn’t really understand when I first read it. It’s becoming clearer now. If my understanding is correct, what you and PaulD-UK are saying is:
- The Pin positions on the R1811 board itself are (from top to bottom) in this picture you posted in November: L+ L- R- R+ (See picture label #1).
- The cables coming from the Cross over unit connected to the right speaker (see picture label #2) are correctly in the + and - position (ie red wire is connected to the + and black wire connected to the -.
- The problem is that when connecting the cross over 4 wire bundle into the R1811 board, the wires for right speaker (ie the two on the bottom (when looking top to bottom) are reversed in that: The black (ie negative) wire is on the bottom and is therefore plugging into the boards (R+) connection (* ie mismatch). And, the red (ie positive) wire (2nd from the bottom) is therefore plugging into the boards (R-) connection (ie a mismatch). Is this correct?
-The solution therefore is: Reverse the wires on the cross over unit connected to the right speaker (ie red wire in the ”negative” side and black wire in the “positive” side.
Is my understanding correct?
Yes, reverse the wires label #2. That is correct 👍
And for the record, I didn't understand it at first either
But the sound test made it very clear
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Awesome!!! Thanks for all of your help. After the speakers are installed, I‘ll be just about ready to button it up (reseal the display! I’ll probably keep it taped up for a while as I’m testing it all.Yes, reverse the wires label #2. That is correct 👍
And for the record, I didn't understand it at first either
Hello mate,
since my setup was complete, I can hear a loud noise from the fan. I tried Noctua fan but it is even loader at full speed. Are you still using it without fan? I found the resistor here but have no idea what Resistance level of Ohm is required? As fan has just two wires, how do I connect to the resistor with 3 wires? thanks
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@Aiwi has said in his blog that his Noctua 40mm fan is made much quieter with a 150 ohm resistor inserted into the +ve wire.
The resistor/potentiometer you have linked to seems to be 50 KILohm (50,000 ohm), which is far too much resistance, not the right value.
Noctua sell a suitable resistor in their 'low noise adapter' NA-RC12, which is 150 ohms.
This should work with the original R1811 fan, or the Noctua 40x10/20.
For a two wire fan you just ignore the yellow wire in the NA-RC12 - just use the + red and - black.
If you want to use a variable potentiometer then you need a 300 or 500 ohm ‘linear’ one.
You connect the centre pin to the power supply + ve and the low end pin to the fan’s red +ve wire.
It is best to insulate the potentiometer from anything else…
The resistor/potentiometer you have linked to seems to be 50 KILohm (50,000 ohm), which is far too much resistance, not the right value.
Noctua sell a suitable resistor in their 'low noise adapter' NA-RC12, which is 150 ohms.
This should work with the original R1811 fan, or the Noctua 40x10/20.
For a two wire fan you just ignore the yellow wire in the NA-RC12 - just use the + red and - black.
If you want to use a variable potentiometer then you need a 300 or 500 ohm ‘linear’ one.
You connect the centre pin to the power supply + ve and the low end pin to the fan’s red +ve wire.
It is best to insulate the potentiometer from anything else…
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I switched the red/white wires on the right side crossover and plugged everything in and everything sounds good from the iMac
. So, I guess I got everything hooked up correctly. The only thing is that the volume is fixed at a certain level and I can’t change it. I saw in one of your posts that you use the R1811’s remote to change the volume. I’m assuming you are using some app to enable this. Is that a correct assumption? I saw one of PaulD-UK’s post where he uses a software called Monitor control from Github to control the volume/brightness of his monitor. Is that the same software you use?
I use the remote to regulate the volume without any problem, yes.
It is not as sensitive as the iMac was originally, but move it far enough, and you can hear the difference. macOS report volume disabled, when using the keyboard.
I hope you will get it sorted
Thanks for the feedback. Hum…I’m not able to move the volume up or down using the remote. I might take a look at that monitor control software and see if that helps.
fantastic, that's I needed. Now I use the same resistor and it's working but it does not lower down the speed smoothly. It's like it gets full speed and at some point I get lower speed. I'm settled for this lower speed for now. I will potentially look for the 300-500ohm resistor. Anyway, thanks for the explanation 👍
Can you mute/unmute with the remote? If not, then I would check to make sure the signals are received by the control card
It’s strange. I can use the remote to bring up the monitor menu, navigate through it, turn the monitor on/off, etc.. It’s just that the mute and volume up/down do nothing. I did download the “monitor control” app from Github and it gives me an icon at the top of my MBP display to control the speaker volume up/down and also the display brightness.
Not sure what would cause that, but at least I have a way to control them.
It is very strange. I have run out of ideas, and I can not test mine in a setup like you have, with the MBP
Are the buttons on the control board still available to use manually? Can you adjust the volume/mute using them? If they don't work the problem could be in the wiring between the control board and main board.
re: Using an iMac 27 main PSU to power a 12V adapter board - JRY-W9CUHD-AA1/R9A18/T18/T19
@stefan786 @USB3foriMac
Ok so I've done a test on a Delta PSU from a 2013 iMac 27":
Basically as soon as I plugged it in it worked.
I used it to power 12v car headlamp bulbs, one 60w and another 55w - so a total load of 115w (12v 9.5A).
It powered both of them at a full 12v without any fiddling with the logic board connection pins.
So it seems to be not as complicated as 2011 and earlier PSUs.
@stefan786 @USB3foriMac
Ok so I've done a test on a Delta PSU from a 2013 iMac 27":
Basically as soon as I plugged it in it worked.
I used it to power 12v car headlamp bulbs, one 60w and another 55w - so a total load of 115w (12v 9.5A).
It powered both of them at a full 12v without any fiddling with the logic board connection pins.
So it seems to be not as complicated as 2011 and earlier PSUs.
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Thanks for all of your help getting me to the finish line
.