Liquileds A548N-G

Liquileds' range of LED lamps have one very unusual feature.  To keep the LEDs that produce the light cool, they use a special synthetic oil.  This model, the A548N-G reportedly has an energy consumption of just 5 W but can produce as much light as a traditional 40 W incandescent bulb.

This lamp has a different shape to its cousin, the A518N-T, which has tube shape, whereas the A548N-G has a globe at the tip.  Because they're cooled by oil, they don't have metal fins like some other LED lamps.

Lighting

This is our photo lab which has a black wall and the light intensity measured in lux in different areas.  The bulb is 1.86 m back from the wall. This lamp disperses light more evenly than the A518N-T, with light spreading out over a wider area.  Given how little there is to round, though, we're not sure that's such a good idea.



We measured light levels of 7.2 lux in the centre of this photo, which is very dim and you can hardly see anything in these conditions.  To brighten things up, you can add more bulbs, but you'll need to add a lot to reach the 100 lux threshold.  Alternatively you can choose a smaller space, like a cupboard, or a bedside lamp, to reduce the area in which the light will be spread out.

Energy Consumption

The energy consumption was lower than the figure mentioned on the packet, and we measured just 4.1 W.

Spectrum

The area of the visible spectrum covered by this bulb is typical of an LED lamp.  To compare it to other bulbs, you can refer to the spectra produced by an incandescent bulb, the fluorescent tubes used in our photography lab, an entry-level compact fluorescent bulb or a full-spectrum model from Viva-Lite.  We produced these spectra using an i1 Pro sensor from X-Rite.


The ideal colour spectrum should be even, with even intensity across all of the colours in the spectrum without any peaks and troughs.  In this case, we found decent enough results, but with the usual hallmarks of an LED lamp, virtually no coverage of violet and cyan areas of the spectrum.  For more information on the benefits of a wider, more even spectrum, read our review of the Viva-Lite bulb.