DIY 5k Monitor - success :-)

[Mowgli10L]

In my R1811 27” monitor I run the A1418 21” fan as slow as it will run.

It has a temperature probe which I set to speed up at 40 degrees C, but it’s never speeded up in the 2 years I’ve been using it.

The only time the internal temperature rose above about 32 degrees C was watching a dark movie at full backlight brightness but the temperature rise was not enough to cause the fan to speed up.

If you set the fan to switch off at low temps it will never run at all…..

Without the low speed fan the case would get gradually warmer, so it is a good idea to use one.

It’s worth ducting the exhaust out of the case like I did otherwise you are just blowing warm air around.

Hi! Thnx for quick reply. Yes, I keep the original blowout/fan exhaust duct aswell as original fan. OK, so I will try no turnoff, but runup from 40 degrees C just like you have done. Maybe set 60degreesC as "Max temp", for full fan speed (just because i need to set one)
The Audio part is the last thing concerning me. Have searched the forum and seen some posts. But do you know if anyone has properly found/calculated the actual Ohm and frequency range of the iMAC original speakers to build/calculate a proper crossover?

 

[PaulD-UK]

@Mowgli10L "The Audio part is the last thing concerning me. Have searched the forum and seen some posts. But do you know if anyone has properly found/calculated the actual Ohm and frequency range of the iMAC original speakers to build/calculate a proper crossover?"

I've written a post about this earlier.
A1418 21" speakers are the same electrically as A1419 27" iMac speakers - each driver is 4 ohms.

This post shows the speaker plug connections.

Each crossover needs an audio quality 10microFarad bipolar capacitor in series with the Tweeter,
and a 0.15 milliHenry air-cored inductor in series with the Main speaker driver.

The small Aliexpress crossover is OK, but the bigger red crossover isn't very suitable.
I've done an analysis.

 

[joergz]

Hey guys, happy Easter.

So I bought two SA1 boards and got both connected via two USB4/TB cables and the help of a Dell WD22TB4 docking station. Technically all is good (e.g. full 10bit support in mac OS). If someone is interested, in the spoiler I added the cables I used and photos of the cable connection in the RAM door.

However, the usage of two of the same boards at the same time causes a luxury problem. Since both identify as "TYPE C" it seems like it's impossible for macOS to understand which is which and after each (!) standby they switch positions - so the right monitor becomes the left etc.. I guess I'm the only one with this issue but I thought I would ask anyway. I also contacted Stonetaskin for support.

Spoiler

USB4 Extension (inside the chassis): https://a.aliexpress.com/_EIii1pa I bought the 30cm Straight version but would now recommend the Left/Right Ear (if it doesn't conflict with other ports usage - I only need USB-C). The cable is quite stiff and there's constraint space. I had to remove a bit of plastic material from the female side as well. The extension pushes the board a bit to the top but since I only screwed it in on the left side it's not a problem.
USB4/TB cable (outside):https://amzn.eu/d/hddgWX0

 

[PaulD-UK]

@joergz Maybe you could rename the monitors using Better Display app?

 

[joergz]

@joergz Maybe you could rename the monitors using Better Display app?

I'm using Betterdisplay and was looking for such an option before but couldn't find it. Also tried Layout protection but that still cannot reliably identify individual screens. It seems to use the names provided by the OS so in my case the protection doesn't work.

Edit: Found it finally. Trying now.
Edit2: Doesn't solve the problem either. Looks like these boards don't provide enough unique identifiers.

 

[PaulD-UK]

Something like a USB-C female to DP 8K male adapter on one of them?

 

[waydabber]

Hi @joergz - if the two boards provide the exact same vendor/moder ID then this issue will happen. But if both are connected to USB-C ports, you might be able to let the app tell them apart if you select the identification method to be "Basic + extended + port" - this should let the app (BetterDisplay) identify the identical display based on which port they are connected to. The OS will still mix them up, but you can force them the way you want using Groups/Layout Protection. Alternatively if you don't want to go through all this or it does not work, you can just want to use Tools/Swap Identical Displays (you can also add a shortcut key for that) to quickly swap the displays.

 

[fhall1]

Has anyone else experienced LED flickering with JRY-W9RQUHD-SA1 or any other board?
I have felt discomfort, headaches and blurry vision using my JRY-SA1 + 2017 iMac panel since I got it setup in December 2024. Since I used an Late 2014 5K iMac for 7 years 8h a day with no issues at all I know I should in theory be able to use this type of screen again comfortably. So at first I thought it was due to DSC so I switched from USB-C input to DisplayPort and reduced color depth to 8bit but apparently it did not help. Then I went to see an optician and was ordinated computer glasses. With computer glasses my vision gets slightly improved but the issues with the 5K monitor did not go away. I have also tested eliminating reflections, tried with different contrast/brightness settings, altering distance to screen but nothing helped. For the last three weeks I have been working in the office with a LG 4K monitor (27UP850) and experienced no issues at all. That made me more eager again to find out if there is some issue with my SA1 5K setup anyway so I made a slow motion movie with my iPhone with no other light source and noticed that the screen actually flickers, even at 100% brightness. Then I pointed the camera to two other screens, one 2021 MacBook Pro 14" M1 Pro and one 2009 Apple LED Cinema Display and none of them showed any flickering.

The video showing LED flickering of the JRY-SA1 + 2017 iMac panel:

(uploading the video as it was recorded, the flickering was not visible so I did slow down the video to 12 images/s and then after upload it was noticeable. YouTube probably reduces frame rate on upload)

I tried to move the backlight cable but it did not change anything in case of any interference. I have read also that the power supply could cause issues and in my case I use a Mean Well 24V 8,8A so I think it should suffice.

So now I am curios to know if any one else with SA1 board having the same kind of LED flickering and also if there are any other boards that don't have? Sadly I am not sure this is what causing my issues but at least this is something that I can measure and I really hope it is. My assumption is even though PWM is used for controlling the backlight it should not flicker att 100%.

I've been using my monitor for 15 months now - never flickered since I built it.

 

[joergz]

Something like a USB-C female to DP 8K male adapter on one of them?

That's my last resort, yes.

Hi @joergz - if the two boards provide the exact same vendor/moder ID then this issue will happen. But if both are connected to USB-C ports, you might be able to let the app tell them apart if you select the identification method to be "Basic + extended + port" - this should let the app (BetterDisplay) identify the identical display based on which port they are connected to. The OS will still mix them up, but you can force them the way you want using Groups/Layout Protection. Alternatively if you don't want to go through all this or it does not work, you can just want to use Tools/Swap Identical Displays (you can also add a shortcut key for that) to quickly swap the displays.

Thanks for your advice. Unfortunately that doesn't work either. Perhaps BetterDisplay is using the Port information about the Macbook Port but not about the port in the Dock? Just guessing. Tried the settings for re-initialization after lock and standby. No change in behaviour.

 

[d0od]

Hi! Back on the track with my monitor conversion of a 21.5" iMac Retina late 2015. Have received a new board (R9513 v5) after the first one (probably) shortcircuited against monitor casing. More precautios about this now! Am keeping the original fan and have connected a 4 pin 12v PWM controller, with temperature controll. The Question is;
1) would you put the temperature controll "free" in the monitor casing or in any special location?
2) What would you use for temperature settings? - I can set a "shut down" temperature, below wich always fan is off, a PWM acceleration temperature, from where the PWM modulates up the fanspeed with rising temperature, and a "fan max" temperature, above wich always full fan speed.
I have no idea what to expect as acceptable temperatures within the casing, and what would be "bad" for the board.
Offcourse i do not want the fan to run more than necessary.

Any chance you could share the controller you bough, how you've connected it and powered by what?

I'm looking to convert my mid-2017 21.5" 4k with R9513 v5 and, tbh, I hadn't really thought about cooling 🙈.

I read that the iMac's internal fan has its 4 wires in a different order to what most controllers expect, and that a separate PSU is needed to control it as the R9513 can't do it (and using a USB-powered PSU is a no-go).

A few threads on here have been enlightening. I've seen a Noctura (?) controller recommended as it lets the internal fan run as low as it would in the iMac, whereas other controllers will it spin at higher values. But I also saw one converter's pic of how the fan was connected to the controller and board and it seemed awfully complex with breaker boards, soldering, big giant batteries involved, etc.

 

[Mowgli10L]

@Mowgli10L "The Audio part is the last thing concerning me. Have searched the forum and seen some posts. But do you know if anyone has properly found/calculated the actual Ohm and frequency range of the iMAC original speakers to build/calculate a proper crossover?"

I've written a post about this earlier.
A1418 21" speakers are the same electrically as A1419 27" iMac speakers - each driver is 4 ohms.

This post shows the speaker plug connections.

Each crossover needs an audio quality 10microFarad bipolar capacitor in series with the Tweeter,
and a 0.15 milliHenry air-cored inductor in series with the Main speaker driver.

The small Aliexpress crossover is OK, but the bigger red crossover isn't very suitable.
I've done an analysis.

Hi!
Thnx again for quick respons Paul! Your knowledge of the posts are way better than the forum search bar
I havent dealt with diy audio before, so may be out of my league, but as i understand it you use a 1st order crossover with the capacitator in series with the tweeter and inductor in series with the woofer. Based on your information that the speakers are 4 Ohm, i played with this calculator: https://www.diyaudioandvideo.com/Calculator/SpeakerCrossover/
I come up with that you have about a 4000Hz crossover. Is that correct?

Question is if we know the frequency response of the tweeter and woofer, to set this crossover frequency?
I see that @5lives in this post: https://forums.macrumors.com/threads/diy-5k-monitor-success.2253100/post-33475083 made some frequency analysis. As i understand the graphs the tweeter graph already has a highpassfilter of 4.7uF included, so dont show the "clean" response curve of the tweeter, or am i wrong?

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[Mowgli10L]

Any chance you could share the controller you bough, how you've connected it and powered by what?

I'm looking to convert my mid-2017 21.5" 4k with R9513 v5 and, tbh, I hadn't really thought about cooling 🙈.

I read that the iMac's internal fan has its 4 wires in a different order to what most controllers expect, and that a separate PSU is needed to control it as the R9513 can't do it (and using a USB-powered PSU is a no-go).

A few threads on here have been enlightening. I've seen a Noctura (?) controller recommended as it lets the internal fan run as low as it would in the iMac, whereas other controllers will it spin at higher values. But I also saw one converter's pic of how the fan was connected to the controller and board and it seemed awfully complex with breaker boards, soldering, big giant batteries involved, etc.

Nice to see another 21.5" converter in here!
I bought this controller from ali-express (4pin version): pwm controller 4pin
The controller gets it power direct from a 60w 12V AC/DC converter, that also powers the displayboard.
The fan pinout from the imacFan as described here by aiwipro. Just have to solder them onto the connector cables for the PWM.
It really is quite simple and straight forward! Havent tried out the settings as reccomended by @PaulD-UK yet.

 

[joevt]

So I bought two SA1 boards and got both connected via two USB4/TB cables and the help of a Dell WD22TB4 docking station. Technically all is good (e.g. full 10bit support in mac OS). If someone is interested, in the spoiler I added the cables I used and photos of the cable connection in the RAM door.

However, the usage of two of the same boards at the same time causes a luxury problem. Since both identify as "TYPE C" it seems like it's impossible for macOS to understand which is which and after each (!) standby they switch positions - so the right monitor becomes the left etc.. I guess I'm the only one with this issue but I thought I would ask anyway. I also contacted Stonetaskin for support.

Don't the EDIDs have different serial numbers? Shouldn't the OS use the serial number to distinguish displays with the same vendor/model?
Actually, I don't recall an OS that did distinguish displays with the same vendor/model by serial number.
Windows allows overriding EDIDs by vendor/model/port combination.

 

[waydabber]

That's my last resort, yes.

Thanks for your advice. Unfortunately that doesn't work either. Perhaps BetterDisplay is using the Port information about the Macbook Port but not about the port in the Dock? Just guessing. Tried the settings for re-initialization after lock and standby. No change in behaviour.

Yes, it uses the MacBook (Apple Silicon) port id, I wasn't aware about the dock, sorry.

Maybe the board allows EDID write (?) - if so, you can try changing the serial number for good that way (note: BetterDisplay won't be able to write EDIDs to devices larger than 256 bytes - this is enough for most writable HDMI dummies but many displays have larger EDIDs nowadays).

 

[PaulD-UK]

@Mowgli10L “I come up with that you have about a 4000Hz crossover. Is that correct?

Question is if we know the frequency response of the tweeter and woofer, to set this crossover frequency?”

I did a frequency sweep test on the tweeters and there is a pronounced peak around 3KHz, so by by choosing a crossover frequency above this reduces this peak and gives an apparent crossover about 3K - which sounded better to me.

A 4.7 microFarad capacitor is correct for 8 ohm speakers, but about half the value needed for the iMac’s 4 ohm drivers. It would put the crossover point an octave (= x2 times) higher.

This would reduce the stereo imaging of the audio.

 

[tornado99]

I'm following this thread with the possibility of converting my 21.5" iMac to a 4K monitor, but obviously more messy due to the lack of a RAM flap on the back. What's the best way of running the cables out?

Also, for now, I'm actually using my iMac as originally designed, using OCLP to run Sonoma. I have a M4 Mac mini connected to the iMac via a thunderbolt cable. I use the (somewhat secret!) Screen Sharing over Thunderbolt to remote into the Mini when needed. This way I get the best of both worlds, M4 for when I need high CPU power, and the gorgeous iMac screen for less demanding tasks like word processing and web browsing.

 

[DJLC]

I'm following this thread with the possibility of converting my 21.5" iMac to a 4K monitor, but obviously more messy due to the lack of a RAM flap on the back. What's the best way of running the cables out?

Also, for now, I'm actually using my iMac as originally designed, using OCLP to run Sonoma. I have a M4 Mac mini connected to the iMac via a thunderbolt cable. I use the (somewhat secret!) Screen Sharing over Thunderbolt to remote into the Mini when needed. This way I get the best of both worlds, M4 for when I need high CPU power, and the gorgeous iMac screen for less demanding tasks like word processing and web browsing.

I pried out the stock power port on my 21.5". It was unnecessarily difficult as it's very securely adhered to the body, but it was doable with some patience and a metal spudger.

I used some white mesh cable tubing so the DP and power cables going in kinda just look like a really fat stock power cable.

Not perfect, but I like it. The only other options I've seen involve cutting up the fan grille, which I don't like at all.

 

[celebrityratowner]

@celebrityratowner - A few questions that might help others diagnose the problem.

1. When does the screen briefly flash gray on the desktop? At startup? At random times while it is in use?
2. If the flashing occurs while it is in use, how often does it happen?
3. Are you using the board to drive anything else other than the display? (For example, audio, fans, etc.)
4. What is your host computer and OS version?

So I went to turn on my computer today and the monitor didn't respond, I removed the LCD and I can't figure out what the issue is, the power supply is still getting power but something isn't getting through. I previously had a small issue with the monitor flashing gray but it seemed to resolve itself within a few days. Can anyone give me some advice about troubleshooting this? Thanks for any help.

Here's my response to the prior issue which went away:

1. I had issues with it doing this gray flash at seemingly random times and it seemed like it was related to the desktop picture but I could be wrong.
2. It was happening every few minutes for the first week or so and then went away completely, I didnt have any issues with it again.
3. I'm only using the board to drive the display, no audio or fans, ect.
4. The host computer is an m4 mini running Sequoia.

 

[PaulD-UK]

@celebrityratowner
Does your JRY--AA1 have a Control Strip with red/green LEDs on it? Does the LED light up?

Intermittent flashing can be caused by static electricity interfering with the video cable from computer to the board, and is solved by using a better quality better shielded cable.

 

[celebrityratowner]

I am not getting any LED's lighting up on the control strip. I did wire the power button to the mac's oem power button on the back, I dont know if this would interfere with the LED's or not. I also soldered the power supply to the output jack so that I could use the oem white power cable as well, I don't these things would be an issue but I could be wrong. I am starting to think that this power supply might be the issue, I'll pull out my multimeter and see what its putting out, thanks for your help!

 

[Archmage2002]

I am thinking of converting my 2017 iMac into a display and stumbled upon this thread. My main goal is to keep the iMac looking stock or at least not an ugly cable mess, I found that insane github build link but I have a few questions and I also have no plan on going as far as he did.

1) Will I actually need the DZ-LP0818 driver board for brightness? Also he used DC-DC converter 24V to 5V 6A step down but I couldn't actually see why he needed that. Would using just two 2 way USB splitters work to get the 4 USB ports working without need to worry about power?

2) Is it possible use the original PSU in the build? I would rather do that then installing one. I was also wondering if it was possible to avoid using a DC barrel plug for the power connection. If not does someone have recommendation for a DC barrel pigtail that would work?

3) I am thinking about running the SA1 board instead of the r1811 board. The $100 price difference doesn't seem worth it for my purpose. Oh and has anybody used these crossovers? Crossover StoneTaskin seems to be promoting them.

4) I noticed that a few people were using 3d printed parts for mounting or custom solutions so I was wondering if there was a list for those solutions or blueprints. Some of them like the custom ram doors look like a great middle ground for avoiding that ugly wire mess.

 

[PaulD-UK]

@Archmage2002
1) For normal use the DZ-LP0818 is not needed.
It's designed to work with the R1811/R9A18 boards, and I've not seen any reports of anyone using it with the JRY-W9RQUHD-SA1 board. You would have to adapt the cable between the JRY--SA1 and DZ-LP0818 boards as the SA1 pinout is different.

@Aiwi used a 5V 6A power source to enable his USB-A ports to power SSD storage and other devices from the USB-A ports. If you don't need that, then don't power the ports.

2) The JRY--SA1 (and the FA1) don't seem to work as well using a 12V PSU to power them. The SA1 definitely needs ~24V in order to power a laptop using USB-C.

So to use the internal iMac PSU you would need a 5+A Boost Converter to raise the PSU output voltage from 12V to 24V.

All the boards have a 4-pin JST XH input connector (++––) to avoid the use of a barrel plug.Either connection needs to be able to cope with the 5+A power current, or the connector will run very hot.

3) The JRY boards all have a fairly low power amplifier built in, and the results will be similar to other low cost moniotors.

The crossovers are perfectly usable to connect the speakers to any board, but the value of the inductor fitted is too high, so it is best disabled with one of the jumpers - Jumper B.
I prefer these crossovers:

https://vi.aliexpress.com/i/1005008109245362.html?gatewayAdapt=glo2vnm