These LED versions are designed as energy saving replacements for the original tungsten halogen filament lamps.
These filament lamps were typically 25 – 50W whereas the LED versions are more often 2 – 4W. As a reminder, these G9 lamps have two, flat pin electrical contacts and run directly off the 230V mains supply.
An important point to consider when buying these LED lamps is the direction the light is emitted. A filament lights all the way round whereas these LEDs can emit light quite strongly in one direction but not in another. Some LEDs are mounted back to back on a flat circuit board which emits a lot of light in the 0°/180° plane but hardly anything in the 90°/270° direction or out of the front end of the lamp. Look at your light fitting to see where you want the direction of light to go.
Another aspect that might be important is the number of times you can switch it on and off. This is known as a switching cycle. This can be important where the lamp is switched several times a day. Lamps controlled by movement sensors switch on and off much more frequently than a typical on in the morning and off in the evening regime.
There is a huge number of suppliers of LED versions of G9 lamps. We have chosen some of the better known names but the list is by no means complete. To make the comparisons similar, we have chosen non-dimmable lamps which are either 2,700K or 3,000K.
When comparing these lamps with an original incandescent one, it is worth remembering that a filament type G9 often produces striations and uneven uniformity when illuminating a smooth surface. Many of the LED versions produced better results.
This has a clear capsule and the LEDs are mounted all around the cylindrical circuit board inside. There is also an LED on the “end” of the lamp, so you get a decent forward throw of light.
This might account for the beam appearing to be slightly wider than with some other lamps.
The all-round frosted diffuser means that the lamp is almost invisible when switched off. Like some other lamps, you could just see the internal structure when turned on but once inside a lampshade or reflector, it would be invisible.
Integral have two types depending on what appearance and light distribution you want. The version we tested has a completely clear capsule which gives a lot of sparkle when switched on. It is also fairly flat in cross-section so it is slimmer than the others.
Like some others, this lamp has a clear capsule with the LEDs mounted cylindrically inside. The additional LED on the end means you get a good all-round illumination.
At 2.6W, this newly released Osram lamp is a slightly higher wattage than the other lamps reviewed. It is also the most efficient and has the highest light output. One other difference is that it has a clear prismed capsule to spread the light. The prisms do cause some slight striations but unless you shine it on a plain white surface, they aren’t noticeable.
When switched off, it appears as a flat orange rectangular strip inside the clear capsule. This isn’t noticeable when switched on. One could argue that the direction of light is stronger in one direction than another but once in a reflector, it is not noticeable.
They make a 1.9W equivalent to a 25W halogen G9 and a 2.8W equivalent to a 35W. The smaller wattage has a slightly frosted diffuser whereas the larger is clear but has extra LEDs on the “top” to project light forwards.
The light is generally diffuse but when it is switched on, you can see the internal supports. Again, this isn’t noticeable unless you actually look; which is what I do.
This is a lower wattage than the others and so it gives a bit less light. However, it is nicely diffused and the light is uniform in all directions.
The 2,700K version gives a soft appearance. You could easily use this as a night light beside a bed.
Data is as quoted by the manufacturers