PSA: Get your flu shot, 2016 edition

A brief digression from your regularly scheduled programming.

Those of you who know me know that I do a considerable amount of work on vaccines. In fact, I’d say that it is the work that I’m proudest of, and it is truly a privilege to work with people who develop and train on vaccines (plus they are some of my favorite clients!)

Among all the revolutions that have come over the past century in modern medicine, I think I can safely argue that–at least from a public health standpoint–vaccines have had the greatest impact on disease burden.

Although this post is about the flu shot, just a note: not vaccinating your kids is an antisocial act. In fact, New Paltz is in the middle of a mumps outbreak. Yes, mumps. Nobody should be getting mumps in 2017. Dear dimwits: Jenny McCarthy is not a reliable source for health information.

I got my flu shot last week. I had a day of lethargy that may or may not have been related to the shot, but certainly nothing that impacted my regular activities. If you are afraid of needles, I should note that the needles on most vaccines these days are so fine that you barely feel them. Really!

John

medicalwriter.net

Lessons Learned (Personal)

Hey all,

In the spirit of being completely open, I’m going to admit that I did something stupid.

I’ve been setting up a fancy audio system in my office–after all, I listen to music 12 hours a day (at a minimum) so it’s a very worthwhile investment. I’m driving a Peachtree Nova from the digital coax output of my computer; I have the Peachtree set up as a preamp (even though it has an amplifier function because I’m using a McIntosh MC275 tube amp. All of this is going to Lipinski 707 studio monitors on my desk. Yes, they are enormous. I have a Y connector from the preamp outs so I can simultaneously run a sub. As nice as the Lipinskys are, they are a sealed-box design, so they have little bass.

 

The other day I decided to try the Toslink output (I had tried the USB output previously, but I can’t get the driver to work on my shitty Windows 7 computer. I had an optical cable still in the package because I was going to use it to drive the audio from my television, but I later found out that the optical out doesn’t work if you are using HDMI in. Why, I don’t know, but that’s what it says in the instruction.

I plugged in the cable to my computer, noting that they fit poorly, and then into my preamp and listened to some music. It sounded subtly crappy. The balance was off a little to the right, the bass was flabby. So I went on a hunt for the problem, switching around tubes, plugging and unplugging things.

Well, I FORGOT TO REMOVE THE LITTLE CLEAR RUBBER CONDOMS FROM THE END OF THE TOSLINK CABLE.

That is all. There goes a couple hours of my life (and 2 minutes of yours for reading this)!

Good news though: I managed a 9.5-mile hike up Gertrude’s Nose in the Shawangunks. A+ hike, a little hard climbing all those rocks with one fully functional and one partially functional arm, though.

John

 

 

All Your Anechoic Chambers Belong to Me

]Went out for a very brief first ride today. Only 9 miles!

So…anyone know of an anechoic chamber in the tristate area that I would be allowed to use–even if I have to do an all-night session? I have several calls in, including one to my alma mater, but no dice so far.

The reason? I need to take some exceedingly accurate measurements in order to design my crossover. Now, I could do them by correcting for reflection from the floor and ceiling, but that wouldn’t be as much fun, would it?

measuring_a_diffuser_in_an_anechoic_chamber

Personal: Finding the Right Cap

As you can see from the below my hobby while not able to ride has become audiophilia. Rational audiophila, but audiophilia nonetheless.

I’ve decided to try my hand at developing an active triamped system using DEQX as a room correction system/electronic crossover (actually, the speaker is biamped and I’ll be running dual powered subs, so in essence it is a triamped system). I’ll write more about what this means, why I’m interested, and how I chose DEQX in a later post–in fact, I plan to document the entire process so that it can be replicated by someone equally naive. It should be interesting, as the hardware comes with a 178-page manual, and I also have to learn about DACs and a lot more details about amplifiers and speakers than my current “that sounds nice.”

I reserve the right to go back and edit these posts, as I’m likely to convey a lot of misinformation as I go along. In fact, I definitely will be coming back to these and cleaning them up so that it becomes an effective guide.

IMPORTANT NOTE: Before I scare you off DEQX forever, you should be aware that a) basic setup, which provides truly astonishing sound, is simple even for the technically disinclined; b) a dealer can set it up for you; and c) you can get a free 3-hour setup session via Skype if you prefer to take a middle route. I am just going the absolute hardest route–setting it up myself and using all of the most advanced features–because I find it entertaining.

I also plan to give some plugs to the various techs and businesses that are helping me figure this out and suffering through my dumb questions.

For now, though, I need a capacitor. Why? Regular passive speakers have a crossover that divides the signal from the amplifier so that the high frequencies go to the tweeter and the low frequencies go to woofer. The crossover acts as a natural protection against the amp frying the tweeter (the woofers are, apparently, more tolerant). Because active amplification means that I’m connecting the tweeter and the woofer directly to the amp, the tweeter needs some form of protection. And that protection takes the form of a capacitor.

So, capacitors (which store electric charge) come in all different values, measured in microFarads. I needed to figure out what size to get. According to the DEQX manual, I needed one that falls 2 octaves below my crossover point (the point where the frequencies are divided into high and low for the tweeter and the woofer), which in this case is 2800 Hz. Octaves are not linear, instead there is a 2:1 relationship. So 2 octaves below 2800 Hz is 700 Hz (divide 2800 by 4). (One octave below would be 2800/2 = 1400 Hz, and three octaves below would be 2800/8, or 350 Hz).

Then I had to get my tweeter data sheet to identify the resistance in Ohms at 2800 Hz–which turns out to be very close to 8 Ohms.

Now, plugging that into this handy formula:

C=1/(2*pi*f*R)

C=1/(2*3.14*700*8)= 2.84 x 10^(-5) = 28 uF

So I need a 28 uF capacitor. That value isn’t common, so I chose a 33 uF capacitor, which I purchased from the nice Canadians at PartsConnexion. Voila!

(Obviously this is a 6.8 uF capacitor, not 33 uF).

Alternatively, you can use this website to calculate the required capacitance:

http://www.claredot.net/en/sec-Sound/high-pass-cross-over-6dB.php

Good times were had by all. Now I have to learn to solder.

Executive Summary:

  • In an active biamped or triamped situation, a protective capacitor between the tweeter and binding post is desirable
  • The correct capacitance is determined in X steps: 1) Get your tweeter data sheet and find the resistance in Ohms at the crossover point you choose; 2) find the frequency that is 2 octaves below your crossover point by dividing the crossover frequency by 4
  • Plug it into the website above
  • Buy two from PartsConnexion (because they are lovely Canadians)

To be continued.

John

Personal: Connecting Cello Stereo Components — The Elusive Fischer 104 Connector

Remember when I said don’t read my personal posts? There are going to be a lot over the next few months as I recover. Just general stuff I’m thinking about.

I have the pleasure and privilege of owning some Cello gear. Cello was a company started by Mark Levinson that sold very high-end audio equipment in the 90s. Many of the components were used in professional audio studios.

For example, here’s the Audio Suite and Palette, perhaps the finest equalizer ever made (I’m a strong believer in the value of tone controls, none of that audiophile short-path pure signal bullshit).

audio-palette

The major problem with Cello gear is that instead of using standard balanced XLR connectors, they used some crazy Fischer connectors because they “sound better” (audiophile bullshit). It’s virtually impossible to find the proper information on these cables, much less get them made.

After extensive research, and some help from my friends at Blue Jeans Cable, I found the correct part numbers. I’m putting them here as a public service announcement so that nobody needs to go through what I did to find these little assholes.

S104A040-80 male with E3104.3/8.7+B strain relief (fits cables up to 8.7mm D).

S104Z040-80 female with E3104.3/8.7+B strain relief (fits cables up to 8.7mm D).

fischer-s104-3-pin

In case you want to make your own cables, you can buy them from Michael Percy at Percy Audio. I recommend Blue Jeans cable though–well made, inexpensive, and no weird superstitious crap about cables and connectors sounding different etc.

Bored yet? I’m making a long list of rides and hikes to do as soon as I recover fully…hoping to get back on the bike by October!

Aumick Road Hike

Yesterday’s adventure was a hike up Awosting Road to the top of the Shawangunk Ridge. I’m almost hesitant to give this one up, as we only rarely see other people on this hike, so I almost feel like it’s my own private path…nevertheless here it is.

Aumick

It’s moderately challenging: About 4 miles (8 miles round trip), 1400 feet of elevation gain. There are a few sections where my mastiff looks at me like “why the hell are you torturing me like this?”

It’s worth the effort, though, particularly when you get close to the top, where the scenery takes a distinctly Lord of the Rings turn. Magnified on the day that we hiked this by plenty of fog. I know my sometime co-blogger John S rides this on his bike, but he clearly doesn’t go the same way we hike this path–it’s far too rocky to ride, and there are 18% plus grades on loose gravel. This picture doesn’t remotely do justice to the beauty of this hike.

A Hike

A hint if you decide to hike it: you’ll come to a number of forks. With the exception of the first, where you’ll take a left, always take the right fork.

John

2015

Hi everyone!

Sorry I haven’t been keeping up with the blog. I have been riding a lot, it’s just that there isn’t quite as much mystery and adventure or as many pitchfork-wielding hillbillies on the Hudson side of the Shawangunk Ridge, so there’s less to report. It’s lovely riding, but it lacks the splendid–and sometimes scary–isolation of riding in the Catskills proper. Yes, I can still get over to my old stomping grounds, but the minimum round trip is 60 miles, so as you can imagine it isn’t a routine weekday kind of thing.

So, this year: Only 3780 miles, assuming I manage to get out for another 80 miles before the end of the year. A pittance compared with my all-time high of 8500+ in 2012, when I first moved to Ulster County. Home ownership and the job have gotten in the way of more time on the bike, but I think this is enough miles to feel reasonably good about myself.

My regular riding companion, who will remain nameless here, has been sidelined by first plantar fasciitis and then Lyme’s disease, poor guy. Yet another reason why I haven’t been out on too many adventures–sometimes it takes a commitment to someone else to spur me on to some of the dumber rides I’ve done. And finding someone who rides the way I do isn’t easy.

20151031_125951

So if you live nearby, like very long rides, getting lost in the middle of a sleet storm,  returning home somewhere between 2 and 5 hours late, and taking long accidental hikes in road shoes over boulder-strewn goat paths in the high Catskills, ring me up. I should mention that someone told me that I like to turn any enjoyable activity into a death march–for example, instead of planting 50 daffodil bulbs like a normal person, I planted over 2500 and managed to strain not one, but both biceps to the point where picking up my new kitten hurt. So it goes with riding as well: It’s not fun unless you’re so burnt that you don’t know how you’re going to make it home!

20151024_130437.jpg

If you’re looking for a good route in the area, please remember that you can always go to my ridewithgps page. Questions? Feel free to e-mail.

Have a happy new year, all.