When he was aged and mostly housebound, the late Andre Previn told me, “A day without music is a day wasted.”

Musicians from Philadelphia to Portland to Paris to Prague have gotten behind that idea in ways that are as unprecedented as the virus pandemic now underway, with virtual concerts popping up from all over the world. Musicians from the Budapest Festival Orchestra have already started a series of chamber music concerts, the “Quarantine Soirees,” that are being webcast every few days.

As conductor Simon Rattle said during a March 12 webcast by the Berlin Philharmonic, “if we are all … going to get used to living more separately than we have for a while, we’re going to need music more than ever.”

The numbers back him up: The Philadelphia Orchestra’s March 12 BeethovenNOW webcast and subsequent YouTube video has reportedly drawn viewership around 300,000.

Even something as niche-y as Tchaikovsky’s unaccompanied choral work Divine Liturgy, sung by Cappella Romana in Portland, Ore., had a reach of 92,704. “There were people from Taiwan to Singapore to Boise — and they were saying hello to one another,” said operations manager Julia Sheridan.

» READ MORE: Coronavirus forced the Philadelphia Orchestra to play to a nearly empty house. And I was there.

On March 16, the Metropolitan Opera began a special series of nightly webcasts from its vast video library (posted daily at metopera.org). The opening installment, Carmen, conducted by Yannick Nézet-Séguin, was so popular that tens of thousands of viewers — “unprecedented traffic” according to Met chief Peter Gelb — reportedly broke the website temporarily. (The Met, which on Thursday canceled the rest of its season, now recommends using its Met Opera On Demand apps to tune in, if you can.)

Such snafus aren’t unusual when so much is being assembled so quickly, even spontaneously, such as the amateur videos from Italy with people playing music to each other — singing, leaning out of windows, and sometimes accompanied by barking dogs.

The classical music world has never moved so quickly. With only a camera phone and a laptop, opera star Joyce DiDonato put together her own March 15 transmission from home (complete with New York City sirens in the background). In it, she and tenor Pitor Beczala sang excerpts from Werther — the opera that they would’ve opened at the Metropolitan Opera the following day had the house not been shuttered.

Reaction was extravagant. By my own count, there were three comments per second.

The whole thing was so charming, personal, and rough around the edges I’m sure I’ll be returning to it even after the health crisis is over. The home/studio acoustics were less than flattering, but it’s the feelings that count.

DiDonato also brought up a difficult point that has gathered steam over the days: Many artists aren’t being paid for canceled concerts. She suggested donating to the Artist Relief Tree (artistrelieftree.com).

That’s a very real problem for Philadelphia’s Grammy-winning Crossing choir, which has moved from presenting its own concerts at Presbyterian Church at Chestnut Hill to being presented by the Annenberg Center and Carnegie Hall.

“Those institutions are very keen to reschedule — we just don’t know when things will be up and running,” said founder/director Donald Nally in an email. “We’ve made some arrangements to help singers in need, though no one has asked yet. I hope they will.”

Music for the peaks and valleys to come

As “new normals” go, our current situation is radical, and changing by the hour and even the minute — not just by the day.

On March 12, the Philadelphia Orchestra was criticized for congregating long enough to stream its Beethoven concert. Now, gatherings of that size are forbidden. An empty-theater taping now being promoted of Massenet’s Manon at the Paris Opera may seem like an event from another era when it airs free on Medici TV starting March 25.

Many concert halls are going beyond the empty stage: They’re being locked up for now. So it’s somewhat remarkable that Philadelphia pianist Jonathan Biss will be making a live-stream recital of Beethoven’s last three sonatas on March 26 from New York’s 92nd Street Y.

» READ MORE: Pianist Jonathan Biss performs with Curtis

In darker moments, I’m haunted by a post-nuclear-war play I saw years ago (can’t recall the title) where the dying denizens of a TV station posted an endless loop of I Love Lucy reruns before expiring. Well, I can be safely haunted by that, since it won’t happen — there’s so much more than Lucy out there now.

Here are some other virtual performances I’ve been counting on to get me through whatever comes next. The choices are based partly on personal taste, and partly on a reasonable amount of certainty that they can be accessed and won’t be canceled (as some events have in recent days).

  • Selections by Igor Levi (on Twitter @igorpianist): This 33-year-old German/Russian pianist and outspoken Twitter presence has long commanded my attention. His new daily, hour-long recitals are thoughtfully introduced in German and English and are programmed according to how he’s feeling that day. On Wednesday, wearing a “Love Music, Hate Racism” T-shirt, he played Schubert’s Moment Musicaux, chosen for its contrast of light and shade, in a performance with volatile extremes and fascinating quirks.

  • Recorded selections by the Crossing choir (#RisingWithTheCrossing on Twitter). If you don’t hear relevance in these daily selections (recorded in past performances), the group’s founder/director Donald Nally will find it for you in the fresh-minted program notes for each posting. Here’s what he wrote for Wednesday’s entry, a movement from Gavin Bryars’ elegiac A Native Hill: “It depends on teamwork over the long, soaring lines; and by the hovering moments in which Gavin allows a chord to linger, to shine, or to brazenly magnify a dissonances. And we can feel in it the love with which it was written."

  • Les Siecles plays Beethoven at the Versailles opera house (online at www.france.tv, search for “Symphonies 5 and 6”). I assume local listeners are well-represented in the 300,000 accessing the Philadelphia Orchestra’s fierce, provocative March 14 BeethovenNOW concert under Nézet-Séguin, so I’m suggesting what might be called the next step: Beethoven symphonies played on historically-informed instruments. In this empty-hall concert amidst coronavirus closures, also from March 14, Les Siecles play with confidence and adventure under the direction of François-Xavier Roth. The visual backdrop is stunning.

  • Pavel Sporcl’s “Concerts from the Living Room” (online at eshop.sporclarts.com, click on the tab at the top of the page). This Czech violinist has undeniable charisma, even if I don’t always love his light-to-medium-weight repertoire. But I want to access his Concerts from the Living Room on principle: He’s one of the very few who is charging money. Not much: 150 Czech koruna comes out to about $6. But while music is free under some special circumstances, musicians have to eat, and Sporcl is setting an enterprising example.

  • Stokowski conducts Beethoven’s 9th on free Pristine Classical download (online at pristineclassical.com.) This French recording label that makes old performances sound stunningly new has a free download, and it’s a doozy: Former Philadelphia Orchestra music director Leopold Stokowski conducts Beethoven’s Symphony No. 9 with the NBC Symphony in 1941. It’s Stokowski at his best — the slow movement is beyond sublime, the final movement is most arresting. It’s sung in English rather than German and communicates emphatically over the decades. The opening line: “Brothers! No more sadness!” Amen.