Lighting and control
GLP impression X4 Bar 20
Choose a pixel or layer mode deliberately, trace common intensity controls and compare motion settings before rebuilding the patch.
Model and purpose
- Manufacturer
- GLP — German Light Products
- Model
- GLP impression X4 Bar 20
- Variant
- Standard RGBW; excludes TH and CwWw
- Light / movement
- 20 RGBW LEDs; zoom 7–50°; tilt 210°
- Power / data
- 100–240 VAC, 50–60 Hz; manual reference 450 VA (W); 5-pin DMX
- Environment
- IP20, dry use; ambient 5–45 °C
A moving linear batten for curtains of light, washes and pixel effects. Normal mode builds looks from overlapping layers; a single-pixel mode exposes individual RGBW cells. Choose that distinction before drawing the console’s selection groups or importing a visualizer model.
Assess the line, background and viewing positions
To assess a light line with the RGBW X4 Bar 20, tell us the approximate background width, available depth and viewing positions. A wash, line of beams or pixel movement can be considered, but quantity, spacing and position need geometry and a rehearsal; zoom alone does not guarantee a uniform curtain of light.
- Choose layered or individual-cell control around the effect. The console profile and selection groups must retain common controls as well as pixels; importing a visualizer model is not sufficient.
- Review tilt travel, dry conditions, supports and actual connections. Alignment joints do not replace support or secondary attachment; identify cabling and distribution already provided by the installation.
- For white looks or cameras, compare actual units and levels before finalizing the proposal. Component history and dimming settings may matter; a common model name does not guarantee matching color or coverage.
Questions to define your proposal
- Do you want a background wash or visible beams and pixels?
- What are the width, depth and viewing position?
- Do you need layered patterns or a precise cell map?
- Do units have different revisions or service histories?
A solution to assess with GLMedia
We can assess an X4 Bar line based on the geometry and desired effect, comparing layered programming with individual-cell control. A photo, approximate dimensions and the intended console help us define positions and color checks. For a stable background, we can compare another wash fixture and simpler preparation.
Ask about rental or purchase with a photo or sketch and approximate dimensions, without a final list. GLMedia can help assess the bar or an alternative and the preparation, mounting, programming and operation to consider in a proposal.
Features and connections
Power uses powerCON input/output; data uses DMX XLR. Plan the distribution from the actual unit, cable, circuit and connector ratings. The alignment pins help line up adjacent units; use the specified mounting brackets and safety attachment for the installation.
GLP documents an LED component change that can produce a visible difference when mixing white. When matching units, record hardware/service history and compare the same look before treating a color difference as a patch error.
Prepare the system
- Confirm the standard RGBW variant, software and installed accessories. Save the show and note mode, address, DMX hold, Silent mode, reverse settings and camera-related settings before changing them.
- Keep the moving head’s full travel clear of scenery, cables and people. Qualified personnel must assess the mounting, secondary attachment and power distribution.
- Use one fixture at limited intensity. Compare the console’s raw output with the selected mode before changing a whole group or applying a reset.
Questions and troubleshooting
I want one cell but pairs or layers change: which mode and selection should I check?
Normal and High Resolution use layers. Single Pixel provides individual cell color, while Dual Pixel combines adjacent cells in pairs.
- Compare NORM/HIRES with SPIX/SPIXH and DPIX/DPIXH on the fixture and in the console. A high-resolution label refines the master dimmer; it does not by itself add independent cells.
- Check that the selected groups include the common controls as well as the intended color cells. A pixel-only group can leave master intensity, shutter, tilt or zoom outside the selection.
- Compare the actual fixture with a slow cell test. A duplicated or incorrectly spaced visualizer model does not establish a hardware fault. Avoid Compressed until its documented footprint discrepancy has been checked for the installed revision.
If cells respond but common intensity is missing, check the group selection and whole-fixture controls. We can help prepare useful operator groups; a macro from another desk/version does not establish your profile hierarchy.
A lower layer stays hidden or the fixture remains dark in Normal: what should I check?
Layer priority and the global controls both affect the visible result. A correctly transmitted color can still be covered by a higher layer.
- Check the common Shutter and Master Intensity first, then the intended layer intensity and color selector. Use the official Normal chart for offsets; another mode places attributes differently.
- Check whether the higher layer’s pattern covers the cells expected from the lower layer. Reduce the test to a simple look and reveal the lower layer deliberately rather than assuming the layers add together.
- For a custom mask, confirm Set Layer 1 and Pattern Select at 255 before evaluating Pixel Select. Preserve the look and compare each change at low intensity.
Tilt is reversed, restricted or absent: what is a useful first check?
Confirm mode and movement settings before recalibration. Some tilt menu options require a separate tilt firmware revision.
- Clear the travel area and compare raw coarse/fine tilt channels with the correct map. Inspect Reverse tilt separately from Reverse pixel and Reverse zoom.
- Read Tilt current, Tilt reset and Tilt slow if available. The manual requires Tilt Firmware V.20 or later for these options; do not assume a missing setting proves a failed motor.
- If movement remains abnormal, stop and record settings and errors for authorized service. A reset can move and recalibrate the head; do not use it as an unattended first test.
How many bars are needed for a continuous background?
We can assess a layout from width, depth, positions and the desired effect, even provisionally. Quantity is not determined by bar length or zoom alone: continuity and coverage need comparison with real geometry.
- A photo or sketch helps assess a visible line, background wash or beam effect. Define audience/camera views and propose sample positions/levels before final quantity.
- For a stable background, assess wash fixtures instead of programming every cell; for pixel movement, include the matching profile, patch and programming in the proposal.
The patch matches but white differs between bars: can the console fix it?
First verify matching looks and settings. GLP documented a component change affecting mixes with white; the same model name does not establish color matching.
- Compare units on the same look/surface without changing several conditions at once. Record revision and service history; do not open or modify the fixture.
- We can assess groups with similar response, verified look adjustments or alternative background lighting. Component replacement belongs with the appropriate service provider, not a console repair claim.
Does a moving backdrop require individual pixel control?
Not always. GLP’s guide distinguishes layered effects from individual control modes. We can choose for the required result and programming time; more DMX slots do not automatically produce a better scene.
- For repeatable color patterns, compare a layered look with the show reference. When every cell must follow a precise map, assess individual mode and the appropriate controller.
- Allow for library, selection groups, patch and transition checks; a mode change may require file adaptation. Keep a copy of the working show first.
- For a short program or limited budget, propose essential looks and a static-background alternative. State which movement and cell detail are included.
Quick reference
| Mode | Channels | Last valid start |
|---|---|---|
| NORM / HIRES | 34 / 35 | 479 / 478 |
| DPIX / DPIXH | 48 / 49 | 465 / 464 |
| SPIX / SPIXH | 88 / 89 | 425 / 424 |
Precautions
- Keep the fixture dry; do not transfer the weather rating of another bar to this model. Keep air passages clear and follow the manual’s heat and clearance limits.
- Protect the lenses from direct sun and other concentrated light. Avoid eye exposure; keep the movement area clear during startup, reset and operation.
- Camera results depend on dimming, PWM and the actual camera. Test the intended look; changing Silent mode or PWM is not a guaranteed cure.
Terms on this page
- DMX
- A data protocol controlling lighting functions; each model defines what its channels mean.
- PWM
- Modulation of LED output; interaction with a camera may produce recorded bands or variations.
- Patch
- Assignment of fixture, profile, address and universe in the control system.
- Shutter
- A fixture function opening or closing light output; distinct from the camera shutter.
Help configuring this equipment
- User Manual v1.8 — software v0.60 (PDF) — glp.de
Start with the model instructions and match the edition to the unit you will use.
- DMX Channel Index v1.6 (PDF) — glp.de
Compare the full personality and function order with the console profile.
- GDTF: profile author, revision and modes — gdtf-development.com
Distinguish the Manufacturer tag from user contributions. Check mode and revision; a compatible file for this equipment is not confirmed here.
Documentation and sources
- GLP impression X4 Bar 20 — product — glp.de
- Programming Guide — X4 Bar 10/20 (PDF) — glp.de
- GLP LED change note — 2022-12-13 (PDF) — glp.de
References: RGBW manual v1.8 and DMX chart v1.6, from software v0.60. Their summary lists Compressed as 19 channels, but the detailed map lists 20; verify that mode before patching.
Guides to plan your system
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