Led Profile Projectors

ETC Source Four Led, a family of four

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With its new Led projectors made to replace the existing traditional lighting, ETC blows the hot and the cold on the light.
The American manufacturer took all his time to develop those products, setting the specifications on very high standards to fulfill even the most difficult Lighting Designer requests with its family of four LED luminaires: Tungsten 3000K, Daylight 5600K, Studio HD with a range from 2700K to 5600K and with its five colors and the Lustr Series 2 with his matrix of 7 different LED colors.

ETC Source Four LED

A full panel

The principle of the Source Four profile, which debuts was in 1992, is to have a single light source body on which you could put different optics. This idea has been preserved on the new LED range, and it has been pushed even further, being able to use the old optics with the new LED profile. In this way, it’s possible to order only the light source and continue to use the old Source Four “nose”. Another very important specification of this fixture was to be designed for a very wide market, from ballet to rock, passing thru theater or architecture.

ETC had to develop several array of light to obtain the maximum quality on a wide colorimetric panel. The Source Four Led range is made of 5 fixtures, and 4 of them will be tested today. All of them are composed by an array of 60 Luxeon Rebel 2.5W Led.

The Source Four CE Tungsten’s LED have all a 3000K color temperature, while the Source Four CE Daylight’s LED are calibrated to 5600K. The 2 other type tested have different LED colors in their array. The Source Four Studio HD fixture has been developed to produce a range of white from 2700K up to 6500K and can be used, even if it’s not his primary function, to create colored ambiences with its 5 LED tints (Red, Red Orange, Mint, Blue, Indigo).

The last fixture, called Source Four Led Lustr Series 2, has 7 colors (red, lime green, amber, green, cyan, blue and indigo). The difference with the previous model (Lustr+ Series 1) is due to the fact that the White LEDs have been replaced by Lime Green and the Red color has been reinforced to obtain a better flux with the most used colors.

The LED Source developed by ETC

The LED Source developed by ETC

All the optics of the HPL range are compatible with the LED fixtures

Philips and BTR Screws

Without having to dismantle anything, we do find a condenser in the lighting box! It’s the first time that the American manufacturer uses this kind of optics. With the lighting source composed by 60 LEDs this is an essential solution to diffuse an even light.

One of the major news at ETC, the condenser !

The connections are made thru two XLR5 connectors for DMX and RDM distribution. To power up the fixture, there is a PowerCON IN/Thru option.

two screws and we have access to the main part

One of the advantages of the low power consumption of the LED Sources is that it is possible to power up several fixtures on the same power line. Ultimately this should allow to make serious saves on power cables.

The first step of the disassembly is very simple; the fixture’s housing is removed easily by removing 2 BTR screws, then it’s possible to access to the two parts that most likely would require maintenance: the power supply and the PCB.

the power supply with the spare fuse

the PCB with the most part of the fixture’s electronics

The rest of the disassembly is a little more difficult due to the volumes optimization. By removing the four screws that are holding the optics and the back of the projectors, it’s possible to see the cooling system. On one side there’s a fan fixed on the fixture back, and on the other side an impressive aluminum radiator.

the fixture’s back and the fan

the impressive radiator

The opening of the optical system is also a little tricky, but the curiosity takes over. It allows to discover the mirror system that ensures the optimum color mixing.

the optical system: six mirrors that mesh the LED colors

On the other side of the optical system’s tunnel, a plate with sixty lenses to channel the LED light is present. It is easily removed and reveals the circuit with all the sources.

the sixty lenses

the sixty LEDs

The software part

ETC pushed really far the fixture’s software capabilities, which ends up in a very multi-functional and very easy-to-use fixture. The display is complete, with the DMX mode, DMX address, status and the ultimate: the DMX chart of the DMX mode used. It’s interesting and ETC it’s the first company to think about it.

The menu is very well conceived and well stocked. The settings are divided in three parts, from the most basic to the most complete.
The first one is for the DMX address.
The second, for the “Quick Setups”, that allows the selection of the built-in presets. By choosing the Studio Mode, it’s possible to manually control the white color temperature even when DMX is not connected.
The third part, “Advanced Settings” allows to set all the options via six other menus.

the display with several information

In the “DMX settings” part, it’s possible to address the fixture, and then, for the multicolor series, to select one of the five DMX chart (only one for Tungsten and Daylight). The choice is complete with the possibility to activate or deactivate the Strobe and Fan functions, or choose automatic fan mode.

A lot of topics have drawn my attention. The seven colors handle is not an easy one, so the modes have been well thought in order to be able to control it in different ways. Two special channels exist: the “White Point” parameter to define the white color temperature ant the “Tint” parameter to handle the green/magenta balance.

Every DMX chart corresponds to a different way to handle the colors. The HSI mode allows working with Hue, Saturation and Intensity while with HSIC mode allows you to add control of White Color Temperature. You can also work in RGB mode if you like to.

The Studio mode favors working with white light while the last one, called “Direct”, is a straight control of the basic fixture’s parameters. The last important point is DMX channel “Plus Seven on/off” when the “Plus Seven” option is activated. This option activates, depending on the fixture model, five or seven extra channels, which directly control the LEDs. This feature allows saving DMX patching space or more control over the colors.
On the other side, the “Plus Seven” activation deactivates the factory color calibration and it’s possible to see a color difference between fixtures. You can also find the “Data Loss” option in this menu, which defines the fixture behavior in case of DMX loss.

The “Led settings” menu holds five parameters:

  • Output, to choose Led Power mode handling
  • Regulated, the one that we used during our test, allows to combine light output and minimum ventilation. Also, this option provides the best color consistency.
  • Protected, is useful for long-term use with a large number of LEDs at 100%
  • Boost, favors power, allows to get maximum output but compromises color homogeneity and light flux regularity.
  • Curve,  handles the LED’s ignition and extinction curve. Choice between four different dimmer curves: standard, incandescent, linear and quick. The second one permits to simulate in the most realistic way tungsten’s filament thermal inertia.

The back panel with buttons for travel in a very extensive menu.

Our friends from Broadcast will highly appreciate the “Output Freq” function regulating the frequency between 920 and 1500Hz with also a “High 25K” mode at 25000Hz.
“Red Shift“ simulates the color temperature shift while the intensity fades out, just as tungsten lamps, and in the same menu you’ll find the “White Point” color temperature setting.

The “Preset and Sequences” part it’s dedicated to a stand-alone use. The “Focus” function overtakes the DMX values and to sets the fixture at 70%, which can be very useful when operating alone without access to the console.
The Presets are light states which have also different fade times. They are all editable on the fixture itself or by DMX capture. And best of all, it’s possible to copy and paste the presets from one fixture to another in the same network! The Sequences are Preset steps. The “Quick Color” menu allows rapid selection of a color without DMX signal.

The “Diagnostic Menu” allows fixture parameters control as well as input signal. The last settings are made in the “Local Settings” menu. The last tab in the menu is far from being the least useful as it provides copies of all fixture parameter, excluding the DMX address, to all the other fixtures in the DMX network.

Another big software development is about RDM protocol. A lot of settings and test can be managed from a console, a peripheral or RDM compatible software. ETC pushed far this development as it is possible to upload the fixture library into an unknown console with RDM features.


It’s time to check if during the reassembly, I didn’t switch the mirror position! To check that, I’m going to make a quick stop at Impact Evenement’s ShowRoom, which have been very kind to host and lend us the necessary tools to test all the devices.

We install all the fixtures on stands and turn them on, all equipped with the same 19° optic. The first impression is amazing. We are totally surprised by the power and especially by the light quality. The second big surprise is the silence of the fan. Fortunately there’s the projector’s light output to confirm that the projector is working! We have to get our ears few inches to the engine to hear the fan humming.

ETC Source Four LED

The four fixtures. In the middle the Tungsten, on the right the Daylight, on the left the Studio HD, and bottom the Lustr Series 2, all regulated in cold white (except the Tungsten which can’t)

The four fixtures. In the middle the Tungsten, on the right the Daylight, on the left the Studio HD, and bottom the Lustr Series 2, all regulated in hot white (except the Daylight which can’t)

As usual with LED projectors, we start with derating test. We turn on the sixty LED sources at 100% and we measure the center enlightenment over the time: first measure after 30 second to avoid considering the starting peak, then every 5 minutes. The enlightenment remains almost at full no matter which fixture we are considering. This first test is very interesting for the video world.


Derating Daylight

Derating lustr2

the almost null derating shows the constant Source Four Led light output

Derating StudioHDDerating Tungsten

Photometric measurements

We already know the 750W Halogen series power, but the use of a condenser changes the rules, especially when associated with sixty led sources! The light is even, the hot point effect has completely disappeared. Depending on color and optics, there are some imperfections on the Lustr 2 model on the beam edge but nothing crippling, and those disappears with the provided diffuser. It can be placed into the gobo slot. The lighting measurements have been made with a 19° optic.

Source Four Lustr 2

Flux ETC Lustr2 EN


The Lustr 2 is the most powerful profile of the range with 2785 Lux in the center and light beam of 4487 lumens. The lighting intensity curve confirms that the hot spot has disappeared. Also, it shows good beam uniformity over the range.

Source Four Tungsten

Flux ETC Tung EN

The Source Four Tungsten with 2084 lux of center enlightenment and 3500 flux lumens is the range least powerful profile.

Source Four Daylight

Flux ETC Daylight EN

The Daylight has 2340 lux in the center and 3825 flux lumens.

Source Four HD


For the Studio HD, we measure an enlightenment of 2300 lux in the center and 3538 flux lumens.


Led intensity variations are very well managed and the four different curves cover most needs. The combination between the “Incandescent” and “Red Shift” options allows a superb halogen fixture simulation.

Dimmer standard ArcDimmer IncandescentDimmer linearOn the colorimetric side, nothing to complain; rendering of the two monochromatic profiles are excellent and can be married easily with other traditional fixtures.

The Studio HD is a very good compromise. With five LED colors, it has a very good white range, and while it is not its strongest field, it can be also used to generate colors.

The Lustr 2 on its side has been designed to deliver the largest color range possible. It handles easily both pastel and saturated colors. The different color control modes make programming easy by adapting the fixture to the personal programming style.

the wide color range of the Source Four LED Lustr Series 2

Gamme couleurs Source Four LED Serie 2 Lustr Gamme couleurs Source Four LED Serie 2 Lustr Gamme couleurs Source Four LED Serie 2 Lustr

Gamme couleurs Source Four LED Serie 2 LustrGamme couleurs Source Four LED Serie 2 LustrGamme couleurs Source Four LED Serie 2 Lustr

Gamme couleurs Source Four LED Serie 2 LustrGamme couleurs Source Four LED Serie 2 Lustr

ETC Couleurs EN

Very good results with the shutters

The last element to test is the shutter module.

The result is very good. There is not perfect sharpness on the shutters, but not far from there.


LED CYC CE, the cyclorama optic that is adaptable to the LED Source Four fixtures

In addition to being compatible with the Source Four full range optics (Zoom 25/50, Zoom 15/30, fixed beams of 5°, 10°, 14°, 19°, 26°, 36°, 50°, 70° and 90°) the Source Four LED has a new feature: the new CYC optic.

The results are as exciting as for the profiles. The light is evenly spread and with the use of the Studio HD or Lustr Series 2 it is possible to light up a Cyclorama with a wide range of color and few light sources.

The next feature of the range will be a Fresnel optic. It’s under development and should be presented soon. We are only missing a PAR optic to replace from the ACL to the PAR WFL in order to have a full and consistent ETC LED range.

The LED beauty

This new range it is an excellent surprise on all levels. The development work has been meticulous, and we feel that at each stage the expectations of the customers and end users have been taken into consideration.
The range is very consistent and can meet the majority of applications. One of ETC’s feats was to make mechanically compatible the standard halogen fixtures with the LED fixtures, but more, the fixture’s light quality allows the new range to be used with any fixture.

The best proof of the product quality is that the sales are constantly increasing, not only with the old range aficionados, but also on a wide new range of customers like TV sets where the Standard Source Four weren’t presents. We can also find those fixtures for rent in several French rental companies.

General ETC EN










Crédits -

Text & photos: Stéphane Mocret

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