Cheap & silent LED moving heads

Tim Vervoort
7 min readDec 27, 2020

For our video studio wanted cheap LED moving heads. On AliExpress, we found the SHEHDS brand. They have a moving head with 19x15W RGBW LEDs. The lyres cost about €150 apiece. I am based in Belgium, so I was happy to see that they have a warehouse in Spain. This means fast shipping and no import taxes (because it’s shipped within the European Union — when we order something from China, for example, we need to pay import duties). Below is the product video for the moving head.

SHEHDS 19x15W RGBWA moving head.

Specs

  • 19x 15W RGBW LEDs
  • 16/24 DMX channels (the difference is the same color for all LEDs or divided into three groups)
  • Zoom: 8–55°
  • Size: 23x19.6x20.1cm
  • Weight: 7.7kg
  • Power consumption: 285W

Review

Previously I owned two Martin mac 250 washes, but they were too heavy and too noisy to be used for video production. I was also surprised about how much a replacement bulb costs (€70-€100).

These smaller and lighter Chinese moving heads seem like a nice replacement for those Macs. I bought two of them to test. After testing them for a couple of weeks, I am still very satisfied with my purchase.

Delivery was within ten days and everything came well packaged. Both devices work fine. There is also no color difference, output power seems identical for all colors, and pan/tilt speed seem to match between the two fixtures.

I use these lights in our video studio, and I am happy that they do not flicker on camera (tested on 24, 25, 30 and 50fps) all on a shutter angle of 180° (1/48, 1/50, 1/60 and 1/100).

They are quite bright and versatile for the price! These moving heads seem to have a greater light output than my Martin mac 250 washes (250W SMD light).

Two moving heads in our studio.

However, I found two minor downsides. The first one is that the center LED uses different color mixing than the outer LEDs. This problem occurs in both 16 channel and 24 channel modes. When mixing colors the center LED seems to use another dimming curve. For example, when using an orange color, the LED in the middle is more yellow, because the green hasn’t dimmed as much as in the outer LEDs. Fortunately, this cannot be seen in the projected light beam, but it is visible on the fixture itself.

Two SHEHDS 19x15W RGBA moving heads in our video studio.

Another problem with the moving heads is that they are quite loud. When music is playing this should not be a problem. But we want to use them in our video productions, so they need to be silent. I tried putting them a few meters away, but you can still hear them in audio recordings.

The problem comes from the two fans in each fixture. There are two 24V fans, one in the base and one in the head. Pictures of the two fans are below. 24V fans are notorious for being quite loud. The general idea was to disable or replace these noisy coolers.

Note: In this article, I’ll explain how we made these fixtures silent, but remember that this will void your warranty.

92mm 24V fan in the head of the moving head.
60mm 24V fan in the base of the moving head.

Cooling analysis

The two moving heads are cooled well, after testing them for an hour in a non-ventilated small room, they still were cool to the touch. Because of this, I wanted to do a quick test with the fans disabled. There is no option in the menu to slow the fans down or to disable them. So I needed to open the fixture.

To view the fan in the head, only four screws need to be removed. The fan itself is connected with four more screws to the head. The fan connector is easily accessible. Note that the fan uses a two-pin 24V connector.

The fan in the base is a bit more difficult to reach. The front (with the LCD screen) needs to be removed by first removing the plastic cover (four screws) and then the metal cover with the screen/connectors (four other screws). Here you can disconnect the two-pin 24V connector. To release the fan, the side with the handle must be removed (four screws and two Allen keys). The fan is secured using another four screws.

After disconnecting the fans, I tested the moving head for some minutes without the active cooling. Of course, they are now silent. However, these fans are there for a reason, so they cannot remain disconnected.

The best idea is to replace the current fans with silent ones. I immediately thought of the Noctua brand. They are known for their near-silent computer fans. One problem though, I cannot seem to find the 24V models. Only 12V models are available in Belgium.

Replacing the fans

12V fans can only be used if the output voltage of the lyre is decreased from 24V to 12V or less. For this, you’ll need a step-down converter. I accidentally bought voltage boosters, this will of course not work and break the booster. Make sure to buy voltage reducers, I bought a couple of them from Amazon. Note that you need two of them in one moving head. I have two fixtures thus need four voltage reducers.

LM2596S DC-DC voltage reducer (step down converter) from Amazon.

To install the new fans, you need to remove the old ones, one from the base and one from the head. I reused the power connectors of both fans. I cut them and soldered the connectors to the input of the voltage reducers.

With the fixture turned on, I used a multimeter when rotating the potentiometer to reduce the output voltage. Do this slowly! When you rotate the potentiometer to fast, there will be some small sparks (luckily both the light and the converter don’t seem to care). I stepped the voltage down to 11V (this results in the Noctua fans not running full speed and keeping them quiet).

Then I cut the cables from the Noctua fans and connected these to the output of the voltage reducers. Then I repeated this for the other fan in the fixture.

New voltage reducer in the head of the fixture.

These are the Noctua fans that I used:

Please note that the NF-A6x25 is not ideal to use in the base of the fixture. A lower profile fan should be more ideal. It fits, but it can only be secured with the two bottom screws as you can see in the images below:

Noctua A6x25 fan in the base. Only the lower two screws are used to secure the fan.
Noctua A6x25 fan in the base. Note that it is too wide to fit. On top of the base is a metal bracket that prevents the fan from being installed correctly. Only the lower two screws are used to secure the fan.
Noctua A9 fan in the head of the fixture.

Here are pictures of the circuit boards where the fans should be plugged in. Note that the fixture does not give warnings if fans are not working or connected (properly), so you need to verify that manually.

Circuit board in the head of the fixture. The fan connector is in the top left.
Circuit board in the base of the fixture. The fan connector is in the bottom right.

Stock fans vs Noctua fans

Of course, the Noctua fans are way more silent than the stock fans. Just to show you how great it works, here is a video filmed with a smartphone close to the head. When you turn up the volume, you’ll hear some room tone, this is not the moving head.

Please note that when you pan, tilt or zoom, those motors will generate some noise.

Cost

  • Moving head: €150,00
  • Noctua NF-A6x25 fan: €14,90
  • Noctua NF-A9 fan: €17,90
  • 2x LM2596S voltage reducer: 2x €2,17 = €4,34

Total: €187,14

Less than €200 is a pretty good deal for a near-silent LED moving head that is quite powerful!

Conclusion

Overall I am very happy with these lights. If you need to light shows with music, you can use them without any modification. Do you want to use them in your video productions like us? Then I can highly recommend that you replace the default fans with more quiet ones like the Noctua fans.

TL;DR fantastic lights but change the fans!

AliExpress link to the fixture: https://aliexpress.com/item/32882759353.html

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Tim Vervoort

Master Computer Science and video producer based in Hasselt, Belgium.