I live in an apartment with a very dated 4-foot fluorescent tube fixture with a plastic puff light diffuser that looks like this: 4 2 Lamp 32 Watt T8 Fluorescent Puff 120 Volt - 20-PLPF248E-120 It gives off the most awful cold light--like in an office or hospital. Even if I change the tubes to warm light fluorescent, it won't help much because the color/coating on the diffuser is a cold icy white. I read about the new LED tubes that you can insert directly into the fixture, but I don't know if they'd give off a warmer light. And again, it wouldn't make much difference because of the diffuser color. I can't find a yellow warm white diffuser on the internet. I can do some minor modifications to the fixture, as long as I can change it back to the way it was when I move out without too much trouble.