books: William Gibson flashes of excellence

Early William Gibson is so white-hot, not just the fantastic Sprawl series (Neuromancer, Count Zero, Mona Lisa Overdrive) but also his short stories, adaptations, and explorations. My 30-year-old web page captures all his output back then, including the rarities.

It’s unrealistic to expect that level of achievement throughout a career, and his subsequent trilogies are pleasant nearer futures with drily comic observations, a lot of cultural and branding references, engaging characters, and not a lot of plot.

He’s picked up steam in the 2010s…

Distrust That Particular Flavor

book cover of 'Distrust That Particular Flavor'

Distrust That Particular Flavor by William Gibson ISBN 978-0-425-25299-4

★★★☆☆ Short non-fiction essay collection is essential for “Down the Line,” his sensational reverie on moving pictures from cave paintings in flickering firelight to a kid playing VR kung fu with classic movie characters.


Elegiac projected future sadness

book cover of 'The Peripheral'

The Peripheral by William Gibson ISBN 978-0 -399-15844-5

★★★★☆ The usual late Gibson: really short chapters intercutting, straightforward weak plot, the characters include a hollow man and a plucky young woman, it leads to a high-tech shootout. Add the tired Macguffin of time travel and my expectations were low. But the time travel has a clever twist, so that the intercutting is between here and now and a far future that’s post-post-apocalyptic; the rural dead-end and war veteran kids are fantastically well portrayed; the future has a bizarre trash cult. It’s the best late Gibson, and I enjoyed re-reading it.


Hilary Clinton lost

book cover of 'Agency'

Agency by William Gibson ISBN 978-1-101-98693-6

★★★☆☆ Gibson returns to the setup from The Peripheral. In interviews he talked about how Trump’s presidency threw his plans for the book into disarray, so he adds an alternate history to the time travel Macguffin which comes across self-indulgent. It’s nowhere near as strong as The Peripheral, continuing its themes but shifting the present-day thread from rural hurt to the same urban flâneur vibe as his previous trilogy e.g. Zero History.


How did I do this?

This blog post has bits of JSON-LD describing my book review that in theory tell search engines what I’m explaining. The post “book reviews yet again” has the gory details.

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Would aliens understand human music?

Listening to people get OpenAI Jukebox continue songs, one is struck by how weird some of its flights of fancy are. Someone wondered what aliens would make of its attempts to make human music:

imagine meeting totally analytical aliens who are only used to math, and helping them understand the concept of human music using this bot… I wonder how it would go, and if they’d be able to understand the emotional meaning…

Al Sebald

Me: Interesting. The pure math of perfect intervals like the frequency doubling of an octave, and the perfect fourth of a fifth ending exactly an octave higher (3/2 x 4/3 = 2!), are independent of culture. They’re not like e.g. letters or counting in 10s. If aliens can hear vibrations, they’ll have music and will be aware of these intervals.

Me: I’m saying their number system might not influence their music, just as our doesn’t, much. If you play one perfect fifth on top of another, eventually you end up at 1.512 = 129.746 times higher frequency, which is almost exactly 7 doublings (octaves) higher; 27 = 128. And if you drop all 13 notes into the same octave range, the intervals between many notes approximate other pleasing relationships like 3:2, 4:3, etc. The way our music combines and sequences notes developed from those relationships, and then Western music mostly settled on making each note exactly 21/12 (the twelfth root of 2) higher, an “equal-temperament” tuning that lets music modulate between any key at the cost of every interval but the octave being slightly off those perfect fractions. Other musical cultures continue to divide the octave into uneven intervals that only sound good in some keys, or divide into 17 intervals (I’m no expert, but e.g. Wikipedia’s Frequently used equal temperament scale).

Maybe aliens don’t hear frequencies the way we do at all, otherwise surely they’ll respond to some of these frequency relationships. Whether they “hear” minor and major the way we do is impossible to tell. If all the aliens’ fleshy vibration organs and their instruments had an 8 octave range (1-256 times frequency) then maybe their music would just jump around all those frequencies instead of humans’ closely spaced dee-doo-doo-dee-dah-dah-dah, and they would think our music is weird. Maybe they have much better absolute time and frequency perception, so all their music is in one key starting at a frequency of exactly 8 trogzomps, and they would think all our key changes are stupid.

It’s fascinating to ponder!

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eco: energy storage is hard, gravity storage is a game

The majority of new electricity generation in North America and Europe is renewable wind and solar, hooray! But they’re variable. The wind and sun may generate more energy than is needed at times, and fall short at others. If the grid doesn’t serve enough variable-demand (like recharging EVs or pre-heating buildings) that customers can shift to avoid low output, then utilities might have to fire up the evil fossil fuel plants. One way to smooth this out is to add energy storage. Tesla has made waves installing big battery packs worldwide to smooth out the grid. This works great to store a few hours of power, which is great to increase the time that wind and solar can provide power, but not enough to make up for a shortfall extending through one or more cloudy windless winter days. So it would be great to some energy storage that’s cheaper than batteries.

We’ve had energy storage for years, in the form of pumped hydro. When electricity is plentiful, pump water uphill into the high reservoir, then when you need it, let the water flow back downhill through a turbine. This works great because a high-up lake holds a massive amount of water (= energy) that you didn’t pay for, and you can make the pipes quite fat (= power).

But two nearby lakes or reservoirs separated by a big vertical drop are pretty rare geography. So we need other kinds of energy storage.

Other energy storage ideas

The mainstream press is full of gee-whiz articles about energy storage. There are many ways to store energy, using:

  • gravity (Energy Vault’s ridiculous tower blocks, Gravitricity’s abandoned mineshafts, ARES’ train a-rollin’ down the tracks 🎶)
  • heat (Siemens Gamesa’s hot stone, Alphabet/Google X Malta’s molten salt)
  • flywheels (MAGFLY)
  • compressed air (two underground caverns set up a decade ago, a few planned that went nowhere)
  • liquid air (Highview Power’s CRYOBattery)
  • hydrogen (every natural gas company greenwashing to appear relevant)

And then there are all the better batteries such as flow batteries, which were apparently untarnished by Nano Quant XXX run by serial fraudster and, I am not making this up, light pop singer Nunzio LaVecchia. Because if you’ve invented a revolutionary battery, you want to screw around making one-off concept electric vehicles and pretending they will go into production.

The latest uncritical coverage of alternative energy storage is “How to store power in soil and salt” on the BBC’s “People Fixing the World” podcast, which covers Energy Vault, Siemens Gamesa hot stone, Malta, and MAGFLY.

But when you look at actual storage bought by private companies with their own money, it seems to be lithium-ion batteries all the way. For example, the article “How US Grid Operators Plan To Tackle Energy Storage at Gigawatt Scale” doesn’t mention anything other than lithium-ion batteries.

Besides, since there will be massively more renewable energy built to electrify land transportation, heating, industrial processes, and Power2X and all of these are potential variable demands, I wonder how much longer-term storage we will actually need.

Anyway, let’s focus on man-made gravity storage.

Start-ups think “Let’s lift something else heavy into the air!”… not thinking too hard. They make great pitches and videos, but it’s close to nonsense.

Why this is dumb part one: common sense

Common sense can be wrong, but you may have noticed:

  • Riding elevators and escalators is free, even in really tall buildings, no matter how much you weigh.
  • Skyscraper management companies don’t roll tons of filing cabinets into their elevators at night and weekends to make some money raising and lowering elevators.
  • You don’t see farmers leaving their heavy farm equipment suspended high in the air before a potential power cut so they can generate some electricity.

Why this is dumb part two: let’s do some math

The potential or gravitational energy in an object of mass m at a height h above the ground is simply m × g × h, where g is the acceleration due to gravity, which is about 9.8 m/s2 at the surface of the Earth

I find a units calculator invaluable to do the energy conversions and keep track of the units for things like this. There’s an online version of the GNU units conversion program and scientific calculator at https://www.fourmilab.ch/webtools/units/ which knows how to convert between units and knows several values including the Earth’s acceleration due to gravity. You can paste all the calculations below into its Convert line, enter desired units in its To field, then click [Convert].

How much energy does it take to raise 1 tonne 100 meters into the air (the height of a 23 story building)

Convert: 1 tonne * gravity * 100 meters

⟶ Definition: 980665 kg m^2 / s^2

Almost a million chunks of whatever “kilogram meters squared per seconds squared” sounds like a lot of energy, maybe we should find a nearby office building and Make Money Fast Tonite! When dealing with electricity we usually deal in kilowatt·hours; you probably pay around $0.10 – $0.20 for each one from the utility whether you use it to run a microwave for an hour or keep an LED lightbulb lit all week.. If you put kWh into the To line of the units calculator, you get

⟶ 1 tonne * gravity * 100 meters = 0.27240694 kWh

Son of a bitch, 1/4 of a kWh doesn’t look like the path to riches! That’s how much energy it’ll take to raise the tonne in the elevator, assuming no losses. Lowering the elevator and spinning a generator is inevitably going to get you less energy than this (no perpetual motion machines in this galaxy), so even if you pay cheap night-time rates to raise a load of crap then lower the elevator when electricity is expensive, you’re going to make at best less than a nickel.

Let’s flip things around a little. Our energy company is competing with batteries. How much can a single rechargeable NiMH AA battery raise? The Eneloop AA is about 1,940 mAh or milliAmpere hours, which means it could deliver 2 amps for an hour. That’s not energy, because how much damage it can do depends on the voltage. The Eneloop’s nominal voltage is about 1.2 Volts. So how high can a single AA battery lift a TON?

Convert: 1940 milliampere hours * 1.2 V / ( 1 tonne * gravity )
To: meters
⟶ 0.85460376 meters

And now you can see why backyard tinkerers don’t hoist their cars int the air in case there’s a power outage: that will barely deliver the energy of a 4-pack of AA batteries. Tesla Powerwall has nothing to fear.

Why this is hard: “Let’s make it up in volume”

Energy = mgh is a simple formula. All these gravity energy storage companies can only fiddle with mass and height. But it’s really hard to increase either to meaningful amounts of storage. To store and recover the same amount of energy as in a Tesla Model 3 midrange battery pack (60 kWh), you’ll need about 300 elevators each lifting a tonne 100 meters. Obviously you want fewer elevators lifting much more weight much further. But it becomes vastly harder to lift 1000 tons a kilometer into the air.

Energy Vault’s idea is to raise and lower 35-ton blocks into the air, constructing and deconstructing a vast Jenga tower. It has an amazing computer animation of how great this is.

Here are pictures (I think, they look real not computer renders) of its demonstration system) in Ticino:

It’s 110 meters tall, so basically the height from my calculation above, but much heavier blocks that are raised and lowered in pairs, one at each end of one of the three gantrie to reduce stress on the cranes. So maximum energy per pair of blocks is

⟶ 2 * 35 tonnes * gravity * 100 meters = 19.068486 kWh

So 1/3 of a Tesla battery for about 140 times the weight. The demonstration crane is not actually raising and lowering anything yet. Here’s the fantasy, showing one half of the cranes dismantling the top of the Jenga tower:

But there are huge problems with this.

The average height each block is raised. The only blocks that benefit from the full height drop are the highest-most ones which are the first ones you lower and the last ones you raise). As you’re dismantling the tower, the blocks generate less and less energy, to the point that it’s not worth lowering the lowest row of blocks. You can only lower every block to the ground if the cranes spread the blocks further away, but now this takes up a lot more space, the crane arms must be much more robust, etc.

The money cost and environmental cost of the materials. Energy Vault claims it’s going to use a cheap cement mix. But the blocks have to fit together well for years.

The money cost of the cranes. Look at how elaborate the demonstration unit is:

That looks hella expensive. Disqus user “dcarde” commented on an uncritical article in IEEE Spectrum (an engineering site!) that the winch to lower two 35 ton weights

is a 4,000 horsepower winch. It is a massive beast 30 feet long, 15 feet wide, weighing 160,000 lbs. It has two big gearboxes with two 1,000 horsepower motor/generators on each (4 motors total for each winch), lube cooling system, a massive emergency friction brake operated by a hydraulic system able to stop a runaway 80,000 load hurtling toward the ground. It has tons of sensors, encoders, and costs about 4 million USD. Yes, you need six of these. And no, they must sit on the ground and feed wire rope up the tower to the jib sheaves 160 meters up. Each winch will also have a 36 foot long house (container) for four VFD drives, regenerative braking system for emergency operation, air conditioning for cooling.

That is before discussing the complication of the Tower jibs. You have three massive slew axes with closed loop positioning to rotate the jib cranes independently, and six horizontal traveling assemblies to radially locate the top block. …

The rapid accurate positioning required. To generate substantial power, the winches can’t lower each pair of blocks in 5 seconds and then slow down and spend a minute gingerly maneuver each block into position while two groups of people with walkie-talkies talk to the crane operator. It has to be fast and completely automated. It has to work in the wind.

The wear and tear on the cables. 1-ton elevator cables have a long service life. 35 ton blocks being rapidly lifted and lowered put a lot more stress on cables.

Gravitricity’s idea is to raise and lower tons of material in existing abandoned mine shafts. ARES’ idea is to drive a train pulling heavy train cars up and down existing steep train tracks. But both have the same problem as Energy Vault – where do you put the weight at the top and bottom? The mine shaft or train track might be several times as deep/high as the Energy Vault Jenga tower, but to store a lot of energy you need to store many units at the top and the bottom of the drop. You need an automated container yard like the ones at a port to move multiple weights on and off the cable at the surface and another one deep underground in the mine; you need an automated switching yard full of rail cars at the top and bottom of the mountain. Gravitricity has the problem that existing mineshafts are narrow. So to increase the mass they have to lower a long narrow heavy weight. That might make the underground container yard impossible, but a single weight permanently in the shaft would put even more stress on the cables, and could be so long that it reduces the height drop.

Gamify it!

Apropos of this, I offer my surefire hit computer game idea for free: Energy Vault Tycoon Simulator!

You try to make money with these contraptions, struggling to code AI to raise and lower blocks fast enough and accurately enough to store/generate electricity at high power, trying to build blocks cheap that won’t wear out, firing and rehiring the cadre of construction workers needed to keep each crane working, shutting down in high winds, realizing that raising then lowering a heavy object actually takes and recoups a tiny amount of electricity, and that many of the blocks you raise and lower generate even less electricity. The game ends in an emotional meeting with Masayashi Son where he says his so-called Vision Fund is pulling the plug on further investment, joining his other venture capital flameouts.

Tagline “Have fun and learn as you fight physics… and eventually lose!”

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music: Trevor Horn gigantism

Bruce Forest, the creator of this everything-and-the-kitchen-sink remix of Grace Jones’ “Sleeve to the Rhythm” provided entertaining background in a Facebook comment on one of Trevor Horn ‘s magna opera/Mount Everests.

“What do you get if you combine 2 years of studio time, the best musicians in the world, two insanely-talented producers and £800,000? The most expensive, and IMO the best produced single of all time, and surely – another 80s masterpiece. ….”

His comment links to another alternative mix. The entire album is basically resequencing and remixing other facets of that one single. This, all of ABC’s Lexicon of Love, Frankie Goes to Hollywood’s “Welcome to the Pleasure Dome”, and Malcolm McLaren’s “Buffalo Gals” are for me Trevor Horn’s highest highs.

Stephen Lipson also reminisces about his own “Slave to the Rhythm” track on Facebook, https://www.youtube.com/watch?v=CTCfBPqeótQ

https://www.youtube.com/watch?v=CTCfBPqeotQ

“I suppose Slave to the Rhythm was the culmination of our knowledge prior to computers becoming the primary recording medium. We did several versions of the song, all totally technology led. Having two digital tape machines allowed us to make multitrack drum loops. Every time the Synclavier was upgraded we’d try another version. It was a time of innovative mayhem.’

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eco: reviving an IKEA Jansjö light

IKEA Jansjö LED desk lamp circa 2009The IKEA Jansjö was amazing 12 years ago, a cheap bright LED lamp when others cost $150. It was $40 (went down to $15 and now may be discontinued). But the switches on them were awful. Both of ours flicker and conk out unless you squeeze or bang the switch just right. I love the final repair step in Fixing flickering Ikea Jansjö lamps : “This POS switch doesn’t deserve UL approval, so remedy that with a Sharpie” 😄

X-ing out the UL approval for the crappy IKEA Jansjö switch, by David Kronstein

Those instructions explain how to repair the existing switch by opening it up and soldering. That was beyond my skills, so I ordered a quality cord switch, the Leviton 5410-W appliance switch for less than 5 bucks. I don’t own “external snap ring pliers” so I just brute-force dismantled the existing crap IKEA switch. Even then it was hard to pull the wires out. Connecting the Leviton switch to the lamp cable was a breeze in comparison.

awful IKEA cord switch remnant on bottom, quality Leviton switch on top

Reduce, repair, reuse, recycle

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science: cocaine-fueled Hollywood-quantum matchup?

Don’t you love those Hollywood-excess parties, where Spiros Michalakis (research professor and manager of outreach at Caltech) is doing cocaine with a bunch of industry heavyweights and remarks “I have a lot of grant money from the National Science Foundation left over due to an accounting error, let’s blow it on a big-budget short film to promote awareness of some of the more speculative aspects of quantum mechanical theory… hell let’s make TWO short films and a ‘making of’ featurette! Quantum babyyyy!! <snort> Ahhhhh”

Today I learned that 3 years ago this actually happened, starting Stephen Hawking, Paul Rudd, Zoe Saldana, Keanu Reeves, Alex Winter, … 🙃

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software: NeWS as James Gosling’s best weird idea

Lex Fridman talked to James Gosling, famous for the Emacs editor and the Java language.

At 1:47:40 he says “I’ve got this weird history of doing weird stuff.” I was fortunate to be writing documentation at Sun Microsystems in the Programming Environments team when he came up with one of the best “weird ideas”: NeWS, the Network/extensible Window System. It used the PostScript language from printers enhanced with object-oriented programming, not just to draw things on your screen, but to exchange and invoke code between your program and the window system (which might be running on another computer across the network).  So instead of calling a fixed triangle drawing function to “draw two long skinny triangles with these points”, a clock program could send the definition of a drawClockHands operator to the window system, and then just send 10 42 drawClockHands to make the window system show the time at 10:42. And you could redefine drawClockHands to draw Mickey Mouse hands, or LED segments, or whatever.

NeWS was an incredible conglomeration of networking, rendering, and language ideas; phenomenal stuff in a world that was only just adopting network programming and OOP, and where program windows with rounded corners only existed on graphics supercomputers. Sun offered it to the other workstations companies, but they didn’t want Sun to control the window system as well as the file system with its NFS [*], so they cast around for an alternative and settled on the far more basic X11 window system.

[*] Sun’s Network File System became a standard on the level of FTP between networked computers, but it didn’t successfully jump onto PCs when they got networked. It was overtaken by Netware which was then destroyed by Windows for Workgroups.

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software: video fixing is possible, but not easy

In your phone’s Google search bar, search for certain animal names, then tap View in 3D, then tap View in your Space. You can even take a video as you move around (and it occasionally lashes its tail). VR is so passé, AR (Augmented Reality) is kewl.

Then spend 10 minutes trying unsuccessfully to turn off the permissions you had to give Google Search to access your camera and microphone (“Let’s film you while searching and analyze your facial expression to see how frustrated you are with Google”, what’s the harm?), and remember to curse Google for discontinuing gems like Chromecast Audio and Google Play Music while screwing around with stuff like this.

Then try to clean up and share the video, and the real fun starts…

Video processing by random walk (ultra-nerd alert!)

My camera was confused filming downward, so the original video had the wrong orientation. You can realign all the pixels to the correct orientation, but it’s even simpler: just change the video’s metadata to indicate that it should be displayed rotated. Linux media processing tools such as VLC and ffmpeg have accrued literally hundreds of options to modify video and audio streams, and I found an incantation to change the metadata:

% ffmpeg -i original_video.mp4 \
        -c copy -metadata:s:v:0 rotate=90 \
    alligator_and_dogs.mp4

Next problem: Android told my phone’s camera to take a 1920×1080 video. Most phones do not have a sensor with exactly this 16:9 ration, so normally when told to capture at a particular size they sample a part of what their sensor captures. Somehow my phone + Google’s software did this wrong, and the video wound up with black bars on the top and bottom. Ffmpeg has a video filter, cropdetect, that detects black bars and outputs a cropping rectangle, but the transition from video to black left a single line of glitched pixels at the bottom of each video frame. I could have probably fiddled with cropdetect‘s parameters to get the right output; instead I took a snapshot in VLC (press [Shift+S]), zoomed into it in a paint program, and found the top bar is 22 pixels tall and the bottom 39 pixels.

Ffmpeg has a crop filter that lets you specify how to crop the input video. But figuring out the format for it was hard. All the guides I read gave a series of ever more outlandish cropping recipes, e.g. crop=in_w/2:in_h/2:in_w/2:in_h/2 ; none of them explained that this specifies an output width and output height then a starting position in the original frame. Once I knew that I worked out that I needed to crop to the input video’s width (in_w), 61 pixels less than the input height, starting 0 pixels over, and 22 pixels down: crop=in_w:in_h-61:0:22. Clear as mud!

Facebook wouldn’t let me upload this MP4 video, because it was too brief. No problem, convert it into a GIF. I also wanted to reduce the file size. VLC’s Tools > Media information > Code said the original MP4 video’s frame rate was 48.408636, so reduce the frame rate to 1/3 of this, 16 fps. Also halve the video resolution with ffmpeg’s scale video filter to (1080 – 22 – 39)/2 = 510 tall (and -1 wide as a magic value to preserve the aspect ratio).

Put it all together and the command to make a cleaned-up small animated GIF out of the video is:

% ffmpeg -i alligator_and_dogs.mp4 \
        -r 16 \
        -vf "crop=in_w:in_h-61:0:22,scale=510:-1" \
     alligator_and_dogs.gif

I didn’t actually check if this made the right adjustments but it looked OK, so ship it. I should fiddle around with ffmpeg’s palettegen options to improve the GIF quality, but this took so much time the alligator ate my dog! 🐊🍴🐕

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music: the best video about music

There are lots of music exploration and music theory videos on YouTube. “The 7 Levels of Jazz Harmony” by Adam Neely is pure joy. Even if you don’t know your E♭maj7 from a hole in the ground, even if you hate jazz, the way he builds on a simple short pop phrase is musical, funny, inspiring, weird. I’ve watched it 7 times, and Lizzo’s “Juice” and the Scoville scale for hot peppers have permanently fused in my brain.

I joined Patreon just to reward Adam Neely for this achievement.
🎼👂🧠❤️ 😍!

If you like this sort of thing, Rick Beato has a great series “What Makes this Song Great” where he breaks down great rock and pop songs track-by-track and moment-by-moment to identify the elements of the composition, production, and performance that make it great. If for example you’ve ever wondered why “Every Little Thing She Does is Magic” by the Police is so appealing despite some cheesy elements, his breakdown is gold.

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skiing: rockers forever

I can tell I’m missing skiing in my bones when I start rolling my ankles on edge when standing still. By mid-summer I miss everything about it, even the frozen fingers, the end-of-day ache overcome for just one more run, … So I’ll relive skiing with delayed blogging about it.

I’m no longer a part-time resident of the-ski-area-soon-to-formerly-be-known-as Squaw Valley USA, instead taking trains to various ski areas. So we no longer own skis; instead we rent performance skis at the resort. In theory this lets me do massive ski evaluations, swapping skis throughout the day to find the perfect ski, as I did when I found my front-side skis.

tip of a rocker-style ski
Clown shoe tip!

Let’s rocker

I knew I wanted to try “rocker” skis. You want a long fat ski with a lot of area to lift you out of deep snow, but a long ski is less maneuverable in bumps and a fat ski is less willing to go on edge and carve. So, just curve the tip and tail up, so that on packed snow they’re flapping in the breeze and you’re effectively riding a shorter ski. The immortal Shane McConkey came up with Volant Spatulas that had reverse camber (so the center of the ski touches the snow), more like a waterski, and then improved the design with K2 Pontoons. Rossignol I think was one of the first to combine the usual camber underfoot (so the center of the ski is off the ski until you weight it) with tips curved up and out of the snow and an odd sidecut. The term of art for this is “rocker.”

The playful Rossignol Soul 7 HD

Several friends swore by the Rossignol S7 when it first came out, and Rossignol has been refining the design for over a decade into the Sky 7, Soul 7, Super 7, Soul 7 HD, … so Rossignol was the first ski I rented a few seasons ago. Even the Soul 7 has been through multiple iterations:

Three generations of the Rossignol Soul 7 (HD)
Evolution of the weird sidecut. But it works! (from the great BLISTER review)

The Soul 7 HD is fantastic. It’s playful, so willing to make different turn shapes. It’s fat underfoot at 106 mm, yet will still carve if you push it. So rather than endlessly swapping skis looking for perfection, my default is just rent these and done.

Head Kore

2018 Head Kore 93 top view

In 2019 the Head Kore series got favorable reviews and won awards, so I specifically tried to rent it. It’s also excellent. It feels more damped and stable than the Soul 7 HD, even though it’s actually lighter (less than 2kg a ski which is really light), and a little faster. In most ways it’s a better ski than the Soul 7 HD, but somehow not as inspiring.

Völkl Mantra 102

Völkl Mantra 102 details
from skiessentials.com

I traveled to Zermatt in Europe, and weirdly the Head Kore was unavailable; all the skiers were bombing down the pistes on skinny short race skis. I tried some skis I wasn’t happy with, then settled on the Völkl Mantra 102. I was dubious since my impression of Völkl’s fat skis was they’re beefy planks for charging Western USA all-mountain skiers: just get them out to the side on edge and power through big turns. I’m simply and sadly not that strong. But the Mantra has morphed into a rockered ski, and it’s pretty great: definitely faster, better edge hold, still decently maneuverable.

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