In use

At this point, the capabilities of Alexa and Google Assistant are well known. To quickly recap, you can ask both speakers to control devices in your home, play audio, answer questions, give you info from your personal accounts (e.g., Google Calendar) and link up to third-party services that make these speakers even more capable.

Given how mature both platforms are, the real question when comparing the Nest Mini to its predecessor is how its new speaker sounds. Google says the Nest Mini has twice the bass as the original, something not terribly easy to measure. It does produce fuller sound than the original, but that's not saying much. When I reviewed the Home Mini two years ago, I said that it was "severely lacking in the bass department and generally lacks the clarity you'd want for listening to music." Harsh but true.

The Nest Mini, on the other hand, is much more pleasant. Doubling the bass doesn't mean a ton when the original speaker had nearly no bass to speak of, but the Nest Mini's sound profile is generally better balanced and less shrill. I didn't consider the Home Mini a viable option for listening to music, but I'd be perfectly happy with the Nest Mini for casual playback in a small room. It's certainly better than blasting music from your phone's built-in speaker, which is what too many people do these days. Indeed, putting aside my music snob sensibilities for a moment, the Nest Mini will probably be fine for large swaths of the population. It's surprisingly loud and keeps its clarity even at higher volumes, and that's about all you can ask for from a tiny $50 speaker.

I can say the same about the Echo Dot. The Dot definitely has better bass performance than the Nest Mini, but at the expense of some precision in the mids and highs. Things can occasionally sound a bit muddier on the Dot, but it has a more pleasant thump. One thing is for sure: The Echo Dot that was introduced last year (and whose design is carried through to this model with the clock) is significantly better at music playback than the older models. Older Echo Dots sound terrible, full stop, while the new one redefined what I thought such a small speaker was capable of.

When doing some head-to-head comparisons, I thought the Nest Mini handled more complex arrangements better. A song like "Graffiti" by Chrvches has major bass, lots of high-frequency synth work, and a singer who hits some pretty high notes. Basically, there's a lot going on here -- and in that crowded soundscape, the Echo Dot came across a bit muddy. But on a more stripped-down track like "Appointments" by Julien Baker, the Echo Dot came across with a fuller, more true-to-life representation of the sparse vocals, piano, and electric guitar. The same can be said for a more robust, straightforward rock song like Death Cab for Cutie's "To the Ground."

Microphone performance is also worth mentioning, and the good news is that both speakers are pretty responsive, even when blasting music. I had to speak slightly louder than I expected to get both to reply, but once I adjusted I was able to get the speakers to pay attention without a problem. Google says that the Nest Mini has improved mics, but I can't really tell the difference. The good news is that either way, you shouldn't have a hard time getting the Nest mini or Echo Dot to hear you.

Which should you buy?

As for which you should buy, your decision ultimately comes down to which assistant you prefer: Google or Amazon. There are slight differences in music playback, but at this point both speakers are very close to each other in sound quality. More important than comparative speaker quality are whether Alexa or Google Assistant supports the music services you use. The Echo Dot's more extensive music service support, coupled with its physical buttons and 3.5mm output, give it the edge for me. But don't get me wrong, if you prefer Google Assistant (or just want a smart speaker you can easily mount to your wall, the Nest Mini is a fine option and a notable improvement over the original.

Micron's stock is at a critical juncture.

While it has recovered by nearly 30 percent since the chipmaker reported a disappointing quarter in December, experts say Micron's fate hinges on its after-the-bell earnings report Wednesday.

"If we look at the history of Micron ... from the 2009 low, we have three distinct declines, each one roughly 70 percent," Todd Gordon, founder of TradingAnalysis.com, told CNBC's "Trading Nation" ahead of the report.

"Thus far, we've only done about a 55 percent decline, so if history is any guide, perhaps we have another 15 percent to go on the downside," Gordon said of Micron's most recent dip. "I'm wondering, if the numbers are weak tonight, could we go down and test that weekly level?"

Gordon said that effect seemed "very" possible going into the report, noting how close Micron's stock currently is to hitting that weekly trend line.

If Micron's quarterly results disappoint again, they could send the chipmaker's stock "down into the $40 range or even lower," he said. "So, if there's weakness, I'll be looking to short Micron in a very confusing semiconductor space."

Michael Bapis, managing director of Vios Advisors at Rockefeller Capital Management, said he was also "super focused" on Micron's earnings, but maintained a constructive view on the company's longer-term prospects.

"We are in a technological revolution that's going to continue, so someone in that space is going to get it right," Bapis said in the same "Trading Nation" interview.

"If [the report is] even close to being OK and people shake off the bad news from last December, I think you can go long the stock," he said. "It's trading closer to its 52-week low than the high, and … there's still demand in the space. It's just a matter of managing the company right, and this earnings release tonight will really help us understand where they're going."

Micron's stock hovered around the $40 level for most of Wednesday's trading session and closed down less than 1 percent at $40.13. Shares of the $45 billion company are up more than 26 percent year to date.

Disclosure: Vios Advisors at Rockefeller Capital Management owns shares of Micron.

Have tech companies gotten so big that it's bad for the economy?

Senator Elizabeth Warren says so. She's proposing to break up not one, but several tech giants, including Amazon, Apple, Facebook and Google. She says they shouldn't be allowed to both run distributor platforms and compete on them. It's like being an umpire and a team owner at the same time.

Spotify co-founder and CEO Daniel Ek is not calling for a breakup, but he is calling for an overhaul – specifically when it comes to Apple. He's pointing to the same issue Warren is: Apple is charging Spotify to operate on its App Store, but then also competing with Spotify in the same store.

So. Is there a problem here? Should big tech be broken up? If not, should regulators step in to change the rules?

This week Jon Fortt sits down with Wired senior writer Lauren Goode, New York Times tech columnist Kevin Roose and former FCC Chairman Tom Wheeler, author of new book: "From Gutenberg to Google: The History of Our Future"

Later on the podcast: Dominique Morisseau is a playwright, a MacArthur Genius Grant recipient, and her musical "Ain't Too Proud — The Life and Times of the Temptations" opens on Broadway this Thursday. A unique innovator shares her journey and you don't want to miss it.

Walmart's chief technology officer, Jeremy King, is leaving the company, according to a memo obtained by CNBC.

King's role has been to revamp the company's technology presence as it looks to compete with e-commerce rivals, namely Amazon. Of late, Walmart is billing itself as a technology company, and not just a retailer, but it has struggled to rebrand itself as more consumers are flocking to the web and mobile to purchase goods ranging from clothing to medicines.

"People all have their own perceptions of Walmart," King told CNBC, ahead of a recent panel at the SXSW conference, about his role leading Walmart Labs, the retailer's technology arm. "For years now ... I've wanted people to understand we are building a tech organization," he said. "I've got a machine learning team. We have some of the best apps in the world."

King hasn't announced his next role, but the memo did state that he'll be starting a "new adventure" soon. It also notes that Fiona Tan, currently the senior vice president of customer technology, will be stepping up into an "elevated role."

King's last day with the company is May 29.

Walmart declined to comment beyond the memo.

Read the full memo here:

After nearly eight years and significant contributions across Walmart, Jeremy King, Executive Vice President and Chief Technology Officer – Walmart U.S. and U.S. eCommerce, has decided to leave the company for a new adventure.

Jeremy joined Walmart during the inception of "a startup within the world's largest company" – now known as Walmart Labs, an important enabler for our business. Ever since then, he's had a laser focus on building capabilities that empower our associates and better serve our customers.

During his first few years at Walmart, he built out an engineering and product organization focused on reimagining the platform for our eCommerce engine, while also leading Walmart Labs through 10+ acquisitions, the opening of four new tech offices and, establishing the organization as a user of, and contributor to, the open source community. The operational decisions made during that time were key to the success of our technology team and led to more agile ways of working, transparent toolsets, product-focused roadmaps and a robust patent program.

Over the last two years, Jeremy's role expanded as we evolved Walmart Labs to not only power our U.S. eCommerce platform, but also our U.S. stores. He encouraged true omnichannel thinking and created a unified team of technologists, each focused on one customer. During Jeremy's tenure, we created important technology partnerships with Microsoft, Google, NVIDIA and others that will help carry our digital transformation well into the future.

Jeremy also championed a strong culture at Walmart. He motivated his teams – especially when it came to balancing technical expertise with empathy and people skills – and promoted diversity and inclusion within Walmart and the tech industry. Jeremy helped build and strengthen relationships with organizations like Grace Hopper, Girls Who Code and Path Forward.

While Jeremy will be missed, he leaves us with an outstanding leadership team and organization well-positioned to advance Walmart's strategic priorities seamlessly and with excellence. We wish him the very best in the next phase of his journey.

Jeremy's last day with Walmart will be March 29. While we look for his replacement, we've asked Fiona Tan, Senior Vice President of Customer Technology, Walmart Labs to take an elevated role as liaison for technology and Walmart U.S. and U.S. eCommerce leadership. Fiona is a strong leader with comprehensive knowledge of our technology stack. During this transition, all of Jeremy's directs will continue to lead their teams and report directly to the both of us.

Please join us in thanking Jeremy for his service to Walmart and wishing him well.