Add and update some papers

papers/derby-av.mdwn

@@ -14,21 +14,15 @@ But after a few bouts you might realize you can save money by doing it
 yourself.
 
 * One speaker: Harbinger APS-15 ($250 new)
-* Two wireless mics: Nady DKW Duo ($60 new)
+* Two wired mics: Shure SM-48 ($60 new)
 
 The important thing about sound at a bout is the announcer, *not* the
 music.  I think a small team would do just fine with a single powered
-speaker, two wireless mics, and somebody's MP3 playlist.  The
+speaker, two wired mics (reasonable wireless mics are super expensive,
+and your announcer shouldn't be wandering around), and somebody's MP3 playlist.  The
 Harbinger APS-15 provides a built-in amp *and* mixer, so you really
 only need these two items.
 
-If you're really on a budget, forget about music and just buy a mic
-system to plug into somebody's home stereo.  The Nady has an
-unbalanced ¼" output; Radio Shack will have a plug to convert this to
-the stereo RCA adapter on a home tuner.  Just be careful moving that
-stuff around:  home equipment isn't made to take the kind of abuse
-it's going to get on the road.
-
 You do not really need to hire a DJ if you can provide a powered speaker
 and mics.  I have been to a number of bouts, each time with a keen ear
 on the music.  I've talked to as many DJs as I could, and with the
@@ -37,6 +31,13 @@ me their job was to set up equipment and play a mix CD provided by the
 team, or a playlist on some team member's MP3 player.  They've all been
 sort of bored.
 
+You should also strongly consider not playing music at all.
+Most music requires royalties payments,
+and playing without securing the right licenses can incur legal threats and
+other BS you don't want to waste time.
+Lastly, can you name another sport that has music during gameplay?
+Just skip it.
+
 If you do want to go for a full mobile DJ setup, though, I have a
 [separate DJ article](dj.html) you might enjoy.  Total cost is
 $650 for that.

papers/derby-helmet.mdwn

@@ -0,0 +1,58 @@
+Title: Choosing a Roller Derby Helmet
+
+Last Update: 21 Jan 2014
+
+There is so much conflicting advice about helmets around there, it's no wonder people are confused about what is actually any good.
+
+There are three kinds of helmets mostly in use by derby skaters, and two more that are gaining popularity:
+
+Hardhats
+--------
+
+Look inside the helmet: is there hard foam covering the entire area? If not, it's a hardhat.
+
+The triple-eight brainsaver with sweatsaver lining is a hardhat. It provides a little bit of padding to cushion blows but is not certified to any standards. It is a good thing to have when rock climbing or working a construction site, but is not rated at all against the sort of brain trauma you'd get in a typical fall.
+
+Bike Helmets
+----------
+
+Is the foam covering the entire area light gray? Does the certification sticker say "CPSC" only? It's a bike helmet.
+
+Many nutcase and triple eight helmets are bike helmets, certified only to CPSC (Consumer Products Safety Commission) for bicycling, somewhat similar to derby. These use a crushable polystyrene foam, which is meant to absorb impact by destroying the structure of the foam. Once you've fallen with a bike helmet on, you need to replace it immediately, because the material can only absorb the shock once. The advantage is that these are cheap.
+
+(Interesting fact: car seat belts are also designed to absorb shock by stretching the fabric weave, but the stretch is permanent. If you're in a crash, replace your seatbelts before driving again: they won't absorb shock and could break bones, or worse, could snap apart.)
+
+Bike helmets are tested by dropping the helmet straight down one time from a height (6 feet, I think) and measuring how much energy is transferred to the meter inside.
+
+
+Multi-Impact Helmets
+------------------
+Look at the foam inside. Is it dark gray, almost black? Does the certification sticker say "CPSC" and "ASTM"? It's a multi-impact helmet.
+
+Multi-impact helmets use a different kind of foam which deforms but doesn't completely crush. In addition to the CPSC test for bicycling, they're also tested against ASTM F-1492-08, a standard for roller skating and trick skateboarding, very similar to derby. It's okay to keep using a multi-impact helmet after falling, but you should still replace it after the event.
+
+Multi-impact helmets are tested by dropping straight down a number of times (four, I think) from a lower height (4 feet, I think) and measuring the amount of energy transferred to the meter inside.
+
+
+MIPS-lined helmets
+---------------
+
+A new technology is making inroads, to add a liner to the helmet and allow the helmet to slip a little bit around. Remember how those tests only test dropping the helmet straight down? It turns out that actual heads on actual people hardly ever hit the ground this way, and this liner is supposed to help with real fall scenarios, where they claim rotational force plays a part in the injury.
+
+Right now MIPS liners are pretty new and pretty expensive. If you have the money, it's probably not going to hurt. But the evidence isn't yet in about whether it actually helps.
+
+
+Hockey Helmet
+-------------
+Does the helmet go over your ears? It's a hockey helmet.
+
+Some skaters have moved to hockey helmets. These are tested against ASTM F1045-07 for ice hockey, a little similar to derby. I haven't looked into this standard so I can't comment much on it. But I think it's important to remember that ice hockey has sharpened skate blades and hard pucks occasionally flying through the air, and is played in cold places. My personal opinion is that an ice hockey helmet is not appropriate for roller derby.
+
+
+Which One Should You Get?
+---------------------
+You should get a multi-impact helmet certified to CPSC and ASTM F-1492-08.
+
+You should never get a hardhat. Unfortunately, most new skaters buy a package deal that includes a hardhat, starting out with the crappiest helmet they can get at a time when they're most likely to hit their head. I managed, after two years of nagging, to convince my league to recommend new skaters get a multi-impact when they start out, and, surprise, they all do. Maybe other leagues could do this too.
+
+Beyond those two certifications for multi-impact helmets, the rest is entirely up to skater preference. I'm a fan of Nutcase, because they were the first company to popularize non-pretentious bike helmets for commuters, but there are a whole lot of manfacturers, colors, and features to choose from. Rest assured that if they meet these standards, you're getting the 

papers/derby-software.mdwn

@@ -1,4 +1,16 @@
-Title: Software in Roller Derby
+Title: Why you shouldn't use Derby Software
+
+Introduction
+-----------
+
+I just (21 Jan, 2014) found this half-written
+unpublished essay on my hard drive.
+There's some good stuff here,
+even though it's not up to my usual standard for publishing.
+Maybe it will help somebody convince their league to keep things simple.
+Maybe I'll rework it to suck less (probably not).
+
+-----
 
 You don't need technology to run a derby bout.  It can make things
 a little easier on the NSOs.  Fans might appreciate rinxter
@@ -53,7 +65,7 @@ computer.
 But their overwhelming desire to automate is precisely why you need to
 be wary of software engineers when you set up your bouts.  We abhor
 mindless repetition--eliminating it is what pays our bills.  But
-someone is going to have start up your infrastructure for every bout,
+someone is going to have start up your infrastructure for every bout and chase down bugs,
 and most nerds are not going to be able to stick with this menial
 task for very long.
 
@@ -67,3 +79,9 @@ $800 computers being dropped or slammed into by skaters/refs, cracked
 screens, etc.  About the biggest problem you might face with the typical
 setup is a 50¢ pen running out of ink, or needing to grab a spare
 $10 stopwatch.
+
+Technology has a place in derby, sure.
+It can help a lot if you bring it in at a rate that you can handle.
+But remember that you can do just fine without it.
+This is coming from a guy who's created three or four derby software packages,
+and two derby hardware gadgets.

papers/dj.mdwn

@@ -5,8 +5,7 @@ Roller Derby bouts for the [Los Alamos Derby
 Dames](http://www.laderbydames.com/), and occasional parties.  All of
 these have pretty similar requirements: music from a PC, maybe some DJ
 mixing, and at least one microphone for announcing.  Derby is slightly
-different because spaces can be larger and the announcer will want a
-wireless mic.
+different because spaces can be larger.
 
 
 My Recommendation
@@ -126,6 +125,16 @@ in the 1980s and 1990s, I don't feel qualified to comment on the Xenyx
 series.
 
 
+Nady DKW-DUO Review
+-------------------
+
+They work okay as long as you stay within about 20 feet of the base.
+And they sure are cheap.
+I've since bought better wireless mics,
+and I prefer to use wired ones if possible.
+There's just less that can go wrong with a wired mic.
+
+
 DJ Controller
 -------------
 

papers/index.mdwn

@@ -8,8 +8,10 @@ useful, too.
 Roller Derby Stuff
 ------------------
 
+* [Choosing a Roller Derby Helmet](derby-helmet.html)
 * [Running Audio/Visual for a Roller Derby Bout](derby-av.html)
 * [Dirtbags DJ Setup](dj.html)
+* [Why you shouldn't use Derby Software](derby-software.html)
 * [Copyright Advice for Small Leagues](derby-copyright.html)