Posted on October 20, 2017
[Note: combine these instructions below for how to lock down AirPlay on an iPad with an app called Volume Sanity and peace will descend upon your house!]
We use Airplay for music throughout the many rooms and audio systems in our house. Our youngest son likes to watch YouTube videos of buses and trucks all day long. In doing so he fiddles around with the settings a lot on his iPad and this inevitably leads to him broadcasting the trucks/busses audio to one of our home’s HiFi’s. This sucks. Especially early in the morning when you awake to the sound of heavy equipment roaring through a not insubstantial sub-woofer in the living room.
Besides the transmission of Airplay audio from his iPad to our home audio, no matter what I do to lock down his iPad under “Restrictions” he’s always finding ways to add events to our Family Calendar and albums full of no pictures to our family shared photo albums.
I wanted to lock down his iPad and disable AirPlay entirely. This turned out to be WAAYYYY more difficult that I thought. After a bit of a rabbit hole I ended up discovering an enterprise deployment tool called Apple Configurator 2. This tool is typically used by large businesses to roll out iPhone or iPads to their employees.
But it also does a really good job at locking down the iPad for our son. Note that following these steps requires wiping out the iPad entirely and starting from scratch so that it can be prepared as a “Supervised” drive. The process is tedious though. If you’ve used Active Directory or any other enterprise profile-type tool you can figure out. Here are some notes though.
Apple Configurator 2 to lock down iPad for child
- download the app from the App Store onto your mac
- launch the app and go to “Preferences”
- create a new organization (i just use our family last name)
- IMPORTANT: Skip enrolling in the Device Enrollment Program
- ERASE THE iPAD: Plug in the iPad and click “Prepare”
- select “Manual Configuration”
- check Supervise Devices (you can only apply restrictive Profiles to supervised devices)
- I checked “Allow devices to pair with other computers.” your needs may vary.
- on the next screen select “Do Not Enroll in MDM”
- The rest of the screens are pretty self explanatory
- Once the device is prepared and appears as a “Supervised” device
- click the App button to install the apps you want on the iPad
- you will need to jump through some hoops to install apps once you apply the restrictive profile so pay attention and install all the apps you want the first time to save yourself some grief.
- Go to File, New Profile
- Fill out the General section
- Fill out the Restrictions section (i mostly unchecked EVERYTHING on this tab
- I also went to the AirPlay section and added a fake MAC address to the whitelist section, ostensibly only allowing my son’s iPad to connect to a device that doesn’t exist. I used for the MAC 00:00:00:00:00:00
- save the profile with a name like “restricted profile”
- click the green “add +” button in the toolbar and add that profile to the iPad.
- You should be all set at this point with an iPad that has working apps and has whatever restrictions you set in the profile
- if you want to install apps after you do this but have disabled the installation of apps in the restricted profile, simply create a new profile that has no restrictions, save it as “unrestricted profile.” Plug in the iPad, delete the restricted profile from it and apply the unrestricted one. Install the apps and then put the restricted profile back on the devices.
- I tweaked the settings in the profile multiple times and just get removing and re-applying it until i got it right.
Posted on August 8, 2017
create a shell script with the following lines:
sudo mdutil -a -i off
sudo launchctl unload -w /System/Library/LaunchDaemons/com.apple.metadata.mds.plist
sudo launchctl load -w /System/Library/LaunchDaemons/com.apple.metadata.mds.plist
sudo mdutil -a -i on
Posted on February 21, 2017
(*Actually only $70 if you already have an amp/receiver to plug into).
We’ve been in our house for almost 10 years and I still haven’t found a good way to take advantage conveniently of the speakers that were built into our Master Bedroom ceiling. The speakers feed into a selector box in the basement which is powered by an audio system in our living room.
The problem with this setup is if I lay in bed an put on some music via the central receiver, the music could also end up playing in the kitchen or living room or outside. At which point I need to head into the basement to fix the speaker selection.
Also, the speakers have an in-wall volume control. And let’s face it, if you have speakers in your bedroom you mostly want a way to play music while laying in bed and not have to get up to dial in the volume from the wall.
So I’ve been thinking of ways to untie the bedroom speakers from the whole house audio system’s selector box in the basement. And I wanted to do so in a way that would not require that I dump a whole lot of money into new equipment.
Other requirements were:
- Control music selection and volume from iPhone
- Have locally stored music available via connection to networked drive
- Play Spotify playlists
- Play from my iPhone via Airplay/Spotify connect (so that if I’m listening to something on my phone when I get back from a bike ride I can just send that audio stream to the bedroom speakers when I step into the shower).
Raspberry Pi 3
For Christmas I bought one of my sons a Raspberry Pi and also picked up one for myself. It seemed like it could play a pretty key role in my bedroom audio solution. This kit seemed like the best deal:
Amazon: $52 Raspberry Pi 3 starter kit
I installed Volumio on the RPi and am really impressed by the feature set (Spotify, airplay, networked drives, etc.). However the on-board audio quality of the Raspberry Pi is really crappy.
After a bit of experimenting I noted that the Pi sounded great when I hooked up my $200 USB DAC to the Pi but that was only a temporary solution as I need that DAC for my living room stereo. Thanks to China and eBay, I picked up this DAC that was built for Raspberry Pi for $18. It took about 10 days to arrive from China and it sounds great (I would be hard pressed to hear the difference between it and my more expensive USB DAC).
The DAC component looks complicated but it plugs right into the Raspberry Pi and has two RCA jacks for plugging into an amp.
It took a few minutes of tinkering to get the DAC working with Volumio but once I got that sorted I just needed an amplifier.
Again, I didn’t want to break the bank and as I was only powering two small in-ceiling speakers I didn’t need a whole lot of power, just something with enough juice to sound nice. I found this highly-recommended little guy on Amazon:
Amazon: $26 Lepy Amp
This little amp sounds GREAT! Now I can lay in bed at night and queue up some music, adjust the volume, set a sleep timer — all without worrying that my Mozart or Miles is blaring through the backyard speakers.
For under $100 I am very pleased with this solution:
- It’s compact – fits in a small shoebox.
- extensible – new features are added to Volumio regularly
- Fun to build
Posted on August 5, 2016
The Red Bank farmer’s market is building up to its annual colorful crescendo right about now. The variety of fruit and vegetables available is pretty good and the prices are reasonable.
The popular stuff abounds — tomatoes, zucchini, peppers — but you can also find some a few examples of strange-looking, less-widely available varieties of eggplant and even daikon and other veggies that you don’t often see available fresh and local at the grocery store.
In past years my trips to the farmer’s market with my youngest son in tow were too frenetic for me to really spend much time shopping so I’d end up spending about $10 on produce that I would be using in the next couple of meals.
As my son’s patience improves (that, and I bring a backpacking chair so he can sit and watch for trains, brilliant!), this summer I’ve got more time to walk around at the farmer’s market.
With the luxury of time to shop, I’ve constructed a bit of a challenge for myself while shopping: I bring $30 cash with me and make myself spend the entire amount on produce. I just buy whatever looks good or interesting and stuff that isn’t already growing in my garden. Then my challenge is to figure out something to make with it during the week.
So as I walk around the market on Sundays, I still don’t know what i’ll be making for dinner for the next few nights. Even as I leave with my Xtracycle bags or my car’s backseat fully loaded with vegetables (it is amazing how much produce $30 gets you!), i have no idea what I am going to do with it.
I just make sure not to waste it. So far it has usually all been used up by Wednesday night, which is fine since Sea Bright has a farmer’s market on Thursday if i need to restock.
Over the past few weeks we’ve done pretty well and have had a several amazing dinners that came together as a result of random stuff in the produce drawer:
- grilled fingerling eggplants and sliced tomato with shaved parmesan with grilled sausage
- beets/balsamic vinaigrette with goat cheese and basil
- breaded and fried zucchini served at room temp with fresh moz and sliced tomatoes and basil from the garden.
- All amazing stuff that i probably wouldn’t have thought to make were the produce not staring up at me from the produce drawer of the fridge.
A side effect of all of this is that the sheer volume of vegetables we are eating in a given week is just massive right now (and, btw, our grocery bill is a bit lower as we seem to fill up faster on veg and serve it with smaller portions of cheese/meat/protein).
So the first part of the challenge for me was just making myself spend some percentage of our weekly grocery bill on produce from the farmers market. ($30 works out to roughly 12% of our weekly grocery bill for our family of four, in case you’re interested.)
The second part of the challenge occurred to me as I walked around last weekend — namely, to try to buy with that budget the widest possible variety of produce I can e.g. as many different items as possible.
SO instead of blowing $30 on the usual suspects (eggplant, zucchini, spinach), i’m buying smaller quantities of those items and more of the less common items like different varieties of radishes or fresh garlic or squashes.
Now, this is purely non-scientific, gut-level intuition speaking here but maybe i’ll try to find some research to back it up: It seems to me that eating a wide variety of produce has got to be a good thing.
Good for us as eaters because, well, variety tastes better and i wouldn’t be surprised if there is some relationship between the diversity of vegetable intake and gut microbiota diversity.
But also good for the planet because — as plays out each summer in my garden where some tomatoes get diseased and others don’t — diversity of crops is key to healthy farming.
When i get home and lay the bounty out on my kitchen table my head immediately starts to combine the stuff I’ve bought with items out of my garden and cheese and meat that I can buy downtown.
It’s a blast and i’ve really enjoyed make dinner for the past few weeks as a result.
Also, and i’ll try to detail this at some point, maybe try taking some fraction of what you’ve bought and just ferment it right away. I’ve got some killer red cabbage and hot pepper kraut bubbling away right now from my trip to the farmers market a couple of weeks ago.
Last week I supplemented my garden’s anemic kirby cucumber output with 2 pounds (for under $3!!!!) of kirby cukes from the market and now have an enormous crock of cukes getting pickled on my counter.
Anyway, to recap my two-part challenge:
• Pick an amount of money (roughly 10% of our weekly grocery bill in our case) and spend it on produce at the farmers market
• try to buy the widest possible variety of items you can, maximize diversity
• (implied third part of the challenge): FIGURE OUT SOME AWESOME STUFF TO MAKE WITH IT ALL!
Posted on August 1, 2016
that’s a gimmicky title. sorry.
but i’ve got this cool little bit of data that is worth having a look at.
So, what does that show?
Well, since January of this year my heart rate variability as represented by the blue line which is a natural log transformed RMSSD (the beat to beat interval of my heart) shows a steady increase. As HRV increases relative to a baseline it can be an indicator of improved vagal health (less stress, better recruitment of the parasympathetic nervous system). Basically, since January I’ve been feeling better and less stressed out.
Working out hard can cause your HRV to plummet the next day or two after hard workout, that’s a sign that your body is repairing itself from the workout. In my case, it also plummets for the next day or so after I play a gig out til 2AM and don’t get good sleep. But anyway, according to the blue line above, even with the gigs and workouts my HRV is increasing!
So note that even though that blue line doesn’t look like it really went up that much, because it’s a log() the increase over time in this case is about a 40% increase in my HRV as measured by rMSSD from January to August.
But what’s more interesting here is that MAF 1 mile test showing a steady DECREASE since January. (Those little green and yellow dots).
The idea behind Phil Maffetone’s training philosophy is to do a lot of long, really low heart rate workouts to better condition the aerobic system. The MAF 1 mile test numbers here show how quickly I can run a mile keeping my heart rate below 135bpm. (obviously, as one would expect, if i go flat-out i’m much faster than the times represented here 🙂
Not only does this low heart rate training do good things for conditioning but – as seems to prove out here in the graph of my little N=1 study – training at low heart rate (in my case 135bpm max) seems to allow me to train and get faster without causing the kind of stress response on my body that would cause my HRV to reduce over time.
Of course, there are about a gazillion other reasons why my HRV could have been increasing since January: I’ve been way more consistent with meditating every morning, I’m eating more carbohydrates (and putting on the pounds to show it 🙂 and have been outside more because it’s summer time. All of those things could also contribute to the increase in HRV.
What’s interesting here though is that i’ve got fitter (or at least faster at the same heart rate) over the past few months without incurring much of a hit on my vagal tone. Prior to 2016 i was tracking my data in different applications and it would take me too long to put up a graph but basically I was working my ass off with a lot of high intensity workouts or long rides/runs with my heart rate at around 70-85% of max and i was getting a bit faster but the trend over time was a reduction in my HRV. meaning while i was getting faster i wasn’t necessarily getting fitter.
Since the beginning of this year i’ve reduced my workout intensity a lot and either go very hard for short workout (90-100% of max HR for a few sprints) or very easy for long ones (135bpm for an hour or more), not too much in between. This seems to be making me both faster and, perhaps more importantly, fitter.
anyway, food for thought. If you want to VERY EASILY track you HRV on your iPhone, HRV4Training is tough to beat.
Posted on December 16, 2015
Heart Rate Variability is a big deal – greater variability correlates strongly with cardiac health, low variability correlates strongly with depression and anxiety*. The rabbit hole at scholar.google.com on HRV is deep and fascinating.
I’ve been tracking my own HRV for many years using a stand alone device called the EmWave. Now though with the advent of bluetooth heart rate monitors and iPhone apps, you can get a whole lot more info pretty easily.
Here’s the deal though: you need to use a really high-quality bluetooth heart rate monitor to get decent data. I had been using a cheap Jarv heart rate monitor for years to track my heart rate while running, riding, doing intervals, etc. And it works just fine for that stuff (if a bit flakey at times and does seem to run the battery out pretty quickly, but, you gets whats you pays for).
I paired up my Jarv with an HRV app on my iPhone though and it reported my variability as wicked low. At first I was concerned that maybe I didn’t have high HRV I thought I had. Then I tried the HRV app with the much more expensive Polar H7 and my HRV #s were way up there.
It appears that the way the Jarv reports the intervals between beats (R-R) is not quite reliable when compared to the way the Polar does the same reporting. I only found one other link on the inter webs that noted the Jarv under-reported HRV and since not everyone may have multiple monitors around to test with, I just wanted to note here that if you start tracking HRV and want reliable data, don’t use the Jarv heart rate monitor. Spring for the Polar one.
* by way of example of just how fascinating the rabbit hole is here: Low HRV correlates with depression but while antidepressants (specifically SSRIs) may alleviate the symptoms of depression, they do not increase HRV. It would be interesting to see a study on whether or not Cognitive Behavioral Therapy (CBT) – which is shown to be as effective as medication in long-term alleviation of depression – causes an increase in HRV.
Posted on March 4, 2015
I’ve been doing some of the workouts in the Chris Carmichael’s Time-Crunched Cyclist book this winter. With another snow storm in the forecast and at least another week on the indoor trainer, I thought I’d share this particular routine.
The most effective-seeming workout in the Carmichael book is the back to back Over-Under days, I’ll explain what Over Unders are below but what’s crucial is that you have a good rest day before day 1, make sure you do full effort on day 1 and 2 and then have at least a full rest day afterwards, maybe even two rest days. Like the book title says though, the workouts don’t take very long, so that’s good. Especially since being on the indoor trainer is unbelievably boring.
Over-Under intervals alternate between a really high-intensity steady state for two minutes and pretty close to all-out effort 1 minute. You alternate between these two states for up to 12 minutes at a time and rest in between sets before alternating again for some prescribed length of time.
Your legs don’t get much recovery during the 12 minute part because after the all-out sprint for a minute you’ve got to return to high-intensity spinning. It’s brutal but helps to burn time quickly on the indoor trainer and the effects are noticeable after just a couple of weeks.
For me, my “Under” heart rate is between 145-155 and my “Over” heart rate is 150-165 (it gets higher towards the end of the workout). Since working this workout into my indoor trainer routine back in November, I’ve noticed increased endurance and longer sustained effort in my legs, seen my resting heart rate come down from 59 bpm to a low of 49 bpm and it makes doing time on the indoor trainer less boring. Anyway, thought i’d share:
From Carmichael book:
“cadence should be high (85-90 rpm). To complete the first interval, bring your intensity up to [92% of your max heart rate] … maintain this for the prescribed Under time and then increase your intensity to [97% of your max heart rate] for the prescribed time. At the end of the Over time return to your under intensity range and continue riding at the level of effort until it’s once again time to return to your over intensity. Continue alternating this way until the end of the interval… Recovery periods between intervals are typically about half the length of the work interval.” [e.g. a 12 minute interval would have 6 minutes of recovery before the next 12 minute interval.]
Over-Unders require that you know your max heart rate or max power on a power meter because you are going to do 92% of your max heart rate for the “Under” and 97% for the Over but i’ve found that after a few intervals you really need a power meter to be accurate because by the second or third set your HR isn’t recovering the same during the Under portion.
I’m not shelling out for a power meter any time soon but here’s my poor man’s way to do this on the indoor trainer.
Find a gear that you can spin at 88-92 rpm and get your heart rate just at the top of your aerobic range. Something that really beats you up but doesn’t have you gasping for breath, this is your Under gear. Then find a gear that you can barely maintain 90 rpm for 60-90 seconds. That’s your Over gear.
I’ve found that if I force myself to maintain cadence of 88rpm in these two gears no matter what interval or set i’m in, i know that i am working the right amount effort for each interval regardless of where my heart rate is – otherwise it’s very easy to start trying to find an easier gear for the Under portion of the interval and you don’t want to do that, the point is to sustain the effort until the end of the complete interval.
So at least once a week work these two back to back days in to the workout
5 min warmup
12 minute Over Under (2 under, 1 over, 2 under, 1 over, 2 under, 1 over, 2 under, 1 over)
6 min recovery
12 minute Over Under
6 min recovery
12 minute Over Under
6 min recovery
5 min warmup
9 min Over Under (2 under, 1 over, 2 under, 1 over, 2 under, 1 over)
5 min recovery
9 min Over Under (2 under, 1 over, 2 under, 1 over, 2 under, 1 over)
5 min recovery
9 min Over Under (2 under, 1 over, 2 under, 1 over, 2 under, 1 over)
5 min recovery
Posted on February 20, 2015
FOTO BY MALIN JOHANSSON.
I’ve been having my mind blown for the past few days by musician Jose Gonzalez. Something about the songwriting on his new album Vestiges & Claws – the way the songs are written around the strengths and limitations of the nylon string acoustic guitar – really drew me in and I ended up going down the rabbit hole and discovering Junip, a band he plays in.
The more I listen to both his solo work and the Junip material, the more I appreciate his guitar playing. From Sweden (born in an Argentinian family), there’s a bit of Nick Drake in his songs.
Start with Line of Fire by Junip on KEXP video:
Here’s a cut off his solo album that will give you a flavor of his picking technique:
You can find his new album on Beats and Spotify or buy it on iTunes. This one, I’m paying for on iTunes even though I can stream it with my Beats subscription.