On one end of the smart bulb spectrum, you've got relatively inexpensive lights that don't change colors. On the other end, you've got fancy lights that do. Philips Hue makes both, but for what seems like ages, they've been ignoring the middle ground: reasonably priced "color tunable" bulbs that don't change colors, but instead, offer a full array of natural, white-light tones. In the meantime, competitors like Lifx, GE, Osram, and Stack have all beaten Philips to the punch.

The Philips Hue White Ambiance LEDs aim to change all of that. They won't put out light in pink, purple, or green like other Hue bulbs, but they will shift color temperatures within that white-light spectrum: warm, candle-like tones at one end and cool, bluish-white daylight tones at the other. The cost per bulb? $30, with a two-bulb starter kit available for $130 (the White Ambiance LEDs aren't available outside of the US just yet, but other Hue products are -- those prices convert to roughly £20/AU$40 per bulb, or £90/AU$180 for the kit).

For the extra cash, the starter kit comes with a handy wireless remote as well as the second-gen Hue Bridge, which brings Apple HomeKit support into the picture. That means you'll be able to control the bulbs with Siri commands alongside other HomeKit-compatible smart home gadgets. And, if HomeKit isn't your platform of choice, you've got a number of other Hue-compatible third parties to work with, including IFTTT, Wink, SmartThings, Nest, and Amazon's Alexa.

That broad compatibility has always been one of Hue's best selling points, but keep in mind that the competition has done a lot of catching up in the last year or so. And, as for brightness, almost all of them have flat-out passed Philips by. Specifically, I'd point to the sensor-powered Stack LED downlights and the Lifx White 800 LED as strong alternatives -- and arguably better ones if you aren't married to HomeKit.

What's new with Hue?

Oh, you know, not too much. The new bulbs look like the old ones, and the new white light spectrum controls have actually been a feature of the full-color Hue bulbs since the very beginning. At $30 a piece, they're essentially taking the place of the soft-white-only Philips Hue Lux bulbs, which were phased out last year.

There is a new Philips Hue app, available for both Android and iOS devices. It adds in new lighting scene presets for your bulbs, including white-spectrum-specific presets like "Concentrate" and "Relax." It also borrows a page from the HomeKit playbook and lets you group bulbs by room. Aside from that, a lot of the differences are purely cosmetic -- though to its credit, it is a better-looking app than before.

More than anything, the new app seems to be optimized around Hue's integration with HomeKit. There's an expanded section in the settings that'll hand control of your bulbs and scenes over to Siri, complete with instructions on how to help Siri understand your lighting commands. When you want to add a new room in the app, it asks if you'd like to import a room from your HomeKit setup. You can run HomeKit-esque lighting "routines" for things like waking up and heading to bed. If last year's debut of the second-gen Hue Bridge represented a marriage of sorts for Apple and Philips, then the new app reaffirms the vows.

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Control your tone

You can change the color temperature of the Philips Hue White Ambiance LEDs with just a few taps in the app. Like in the old app, you'll drag a little cursor to the specific tone that you want, though the new app omits the full RGB color spectrum with these white-light-only bulbs, and gives you a full-screen white-light spectrum, instead. Nice touch.

But a good smart lighting setup shouldn't be too reliant on an app -- ideally, you'll be able to automate lighting changes that anticipate your needs, saving you the trouble of pulling your phone out of your pocket. To this end, Hue's new timed routines are a good step in the right direction, especially the location-aware routines that track your phone to run automatically as you leave and come home.

Enlarge Image Screenshot by Ry Crist/CNET

It also helps that Hue's LEDs are about as bullish on voice control as bulbs come. Aside from the integration with Siri, Philips Hue setups enjoy native support from Alexa, Amazon's voice-controlled virtual assistant. Philips is wise to position itself at the front of the curve here -- voice-activated lighting can quickly make app controls feel antiquated.

I've got just one qualm here: Siri doesn't have a vocabulary for the white light spectrum. Ask her to set a bulb to "daylight," or "soft white," or "2,700 K," and nothing will happen. She has no idea what those terms mean.

That's a bit baffling, frankly. Philips Hue was an early and enthusiastic member of the HomeKit bandwagon, and that white light spectrum's been there from the beginning. Maybe teaching Siri to recognize thousands of specific color temperatures is a bit much, but would it have been so hard to let her know what "daylight" means? The color tunability and the Siri compatibility are the two top selling points here -- why is there a wall between them?