In an earlier review of the IKEA Lunnom Filament LED Globe, I noted the increase in popularity of vintage mood lighting and the number of incandescent “carbon-filament lookalike” globes that had flooded the market just as incandescent bulbs were being phased out. LED globes are the way of the future, so the trend seemed rather regrettable.
Despite this, I still wanted to get my hands on a carbon-filament lookalike globe while I still could. Luckily for me, strolling into a Bunnings store, it seemed that some of the older stock was being cleared out for AU$2-3 a globe which was so cheap that I decided to pick up both a filament type globe and a newer LED-filament type globe for comparison.
Philips 25W Vintage T30 Filament Globe
The first globe to be tested is this Philips Vintage T30 25W B22 globe, rated for 220-240V. The globe claims a lifetime averaging 1500 hours – a little more than the average incandescent that would normally be rated for 1000 hours. But nowhere near the rating for LED globes.
Its colour temperature is claimed to be 2700k, which is just a normal warm white, and also claims to be able to withstand 8000 switching cycles. It comes up to full brightness immediately and is suitable for dimming (owing to the incandescent technology).
The globe is Made in China, but distributed in Australia and New Zealand.
With a claimed output of 60 lumens, this globe achieves just 2.4 lumens per watt.
The T30 style globe resembles a long “sausage”. The filament runs in a U shape down to the tip and back. The base is a nice golden brassy colour, and the envelope seems to be “metallised” internally to make it appear even warmer.
Because it works like a good-old incandescent lamp, it features a traditional BC base that is identical to what you would find on regular incandescent globes, rather than the more plastic variation on modern LED retrofit globes.
Looking up-close, a very thin coiled filament is supported by a number of support wires along the length.
Lighting it up, it produces a quite warm and full glow, which is not particularly bright but good for decorative effects. If you’re used to LED globes, the light actually seems “fuller” – this is probably due to the continuous nature of the spectrum from incandescent globes. The long filament does vibrate somewhat sympathetically with the mains frequency resulting in some “flicker” when viewed at just the right angle to the glass.
As a simple bulb, it works across a wide range of voltages, although the output very much depends on the input voltage. It looks like the globe is about 22W at 220V and 25W at 240V, which means the labelling is practically spot-on (as Australia was a 240V country). The one good thing is that the power factor is unity – it’s basically a resistor after all.
Philips 4.3W Classic Design LED Globe
This was probably an earlier LED replacement globe which has now been deleted from the catalog. With a rating of 4.3W, it might sound weak, but it delivers a whopping 470 lumens – 7.8x more light than the 25W globe above and achieving a very respectable 109 lumens per watt efficacy. The globe claims to have the same 2700k colour temperature, but is not dimmable and usable within 170V-240V. It claims a lifetime of up to 15,000 hours – ten times longer than the filament globe above
The main attraction of this particular globe is that the whole globe is in a traditional GLS A-series bulb envelope, so it will fit into every regular fixture. The glass outer envelope serves the function of insulation, but is not evacuated as it doesn’t need to be. It seems that all four LED filaments are paralleled in this design.
The BC base is a plastic-insulator type, with the driver integrated into the base.
Even the outer glass envelope is marked just like a regular filament globe as well, which is pretty cool. It is Made in China as well, with an Australian RCM.
The globe starts off with close to 4.6W consumption, quickly warming up and settling around 4.4W – so very close to the claimed 4.3W rating.
The globe is found to be workable and regulated down to about 120V. Below there, the globe flashes and cycles between about 60V and 80V, and runs at reduced brightness at about 80-120V. Power factor is a rather “ordinary” 0.55-0.58 within the main 220-240V working range.
Oddly enough, the colour of the light coming out of the globe feels somewhat cooler despite having the same claimed CCT. It’s also a bit bright to look at directly, and the look of LED filaments are not quite as delicate as the thin filaments. I can still see why there is an allure to the regular filament globes.
The Philips Vintage filament globe is representative of the “decorative” filament globe. It achieves just 2.4lm/W, producing 60 lumens which is pretty dim. It has disadvantages of being fragile due to the filament and a limited lifetime. However, it does have an allure of having the delicate filament visible, a warmer full spectrum light and a brightness that does make it rather pleasant to look at.
The Philips Classic Design LED globe is an LED retrofit that tries to replace the filament globe. With a very efficient 109lm/W, it is 45.5x more efficient and can even provide general illumination with a much longer lifetime. The light quality, however, does feel somewhat cooler and harsher and lacks the delicate look with the thick LED filaments. The brightness makes it somewhat less pleasant to stare at.
I guess it is a worthwhile trade-off to save money and the environment to go LED, but filaments do still have the upper hand of looking cooler and more “retro”.
Bonus: Older Filament Bulbs
Now that most incandescent globes are outlawed and the only sort that are available are halogen retrofits, I was pleased to find my old collection of incandescent globes which consists of a range of pearl/frosted, clear, round, fancy round, candle-shaped, reflector spot, etc types.
I got a few of the clear globes to take a few macro shots …
An unbranded 100W globe – short coiled thick filament with two intermediate supports.
Looking closer at the filament – it’s a coil of coils. Below is another globe – a cheap variety-shop 60W globe with five insulated supports!
It seems the filament on this globe is made of a single strand that is coiled.
Finally, going down to a 25W globe, we can see that the filament has stretched from a number of years of use, with more stretching around the supports – this filament is now more vulnerable to failure by shock and by developing “thin” spots. But as expected, lower wattages mean thinner filaments.