Tools are what we use to do what we do.
All about the hardware.
 Evolution of a gong rig
The stuff you have pretty much determines the quality of what you can achieve. But what you have to haul around determines a lot about the scope of your project: how far you can go, where you can reach, how much attention you attract, how many of you need to participate. Sometimes even subtle changes in the technology have a major impact. Here's an initial gear comparison.
 Proof of concept
There were several advantages to this approach to portable pickups:
- It was cheap because we already had the parts lying around (Admittedly, that would be a rare coincidence for most). The V-100 street price is around US$100, but if you have one you're not using, why not?
- It is totally portable, and doesn't require any adhesive or putty
- It turned out to be quite sensitive, with a surprisingly wide frequency response
- It is lightweight and small
- Handling noise. A hand-held device with wooden feet picks up every bump and slip you make. The rubber guard we rigged helps some on the "handle," but the bridge feet slip around on metal surfaces
- User fatigue results from clamping the bridge to the your subject for long samples
- Compared to purpose-built devices, this is a pretty fragile setup
In the end, though, this got us to the next stage. We knew the Golden Gate Bridge made interesting sounds loud enough to record easily using mid-range audio gear. That was enough to start.
 A tool upgrade
We got a little more sophisticated in time for Golden Gate Bridge Assay #2 with the Sony and the Schertler pickup. Of course, the remarkable Sony "tribble" windscreen flies in the face of our most serious endeavor. Full-size image: Media:PCMD50_Schertler.jpg
Our obvious next step is to optimize the cabling. An XLR connector is great on stage and in the studio but ridiculous at this scale. It's time to take that fine Neutrik XLR off the Schertler and replace it with a 2.5 mm right-angle plug. Once we do, we'll post the result here. But the Sony PCM-D50 rig probably won't get any sweeter than that.
Top of Article
 Big rigs
Every now and then something comes along that requires a bit of distance and a lot of bass: seismic survey trucks and commuter trains, for example. We spent a couple of nights researching kick-drum mic options and then Jacob opted for a rental. The massive nature of the setup leaves little to the imagination. The black "dongle" in the photo is the phantom-power battery pack. Original image @ Jacob's Flickr page
In use? It's every bit as massive as it looks. Lightweight by 1970's standards, of course, the M-Audio Microtrack is dwarfed by the phantom powered field mic in this experiment. Note the classic juggler's hand position used to aim the mic, access the recorder pushbuttons, and keep the battery pack from dangling.
Jacob's posting the results of the latest Long Beach geophysical survey on our Sounds page. Those interested in this offshoot of our investigations are encouraged to check out the Center for Land Use Interpretation's web page for a look at oil prospecting and its impacts on surrounding urban ecosystems such as Long Beach.
 Mobility and wideband recording
It's not so straightforward typing on the phone as recording has become. Look here again soon for a discussion of our current experiments with Android and the Xperia X10. (This edit made from the phone. Mr Yesterday 09:49, 10 November 2010 (MST))
OK, "soon" is now....
 Xperia X10
Dave's latest mobile is a Sony/Ericsson Xperia X10. Starting on Android 1.6 and upgrading to 2.1, we find the service acceptable and a range of recording apps widely available. Here's what a mobile phone equivalent to the PCM-D50 looks like. Full-size image: Media:X10_04.JPG.
Note: AT&T is no longer carrying or supporting the model as of late 2011, and without Flash support on the older Android 2.1 OS, this has gotten increasingly disappointing. It's a consumer device and obsolete almost the day you buy it, alas.
The X10 running the TapeMachine app (€3.99 from Samalyse) seems to do a quite serviceable job of capturing CD quality sound using either of the two mics built into the phone's body or using the wired mic that comes with the unit as a contact microphone. Note the Schertler putty used to isolate and attach the wired piezo mic to a resonant object--it's the green ring around the little black barrel at lower right. Here's a clean sound sample taken with and edited entirely on the X10.
 Compact and adequate
You're probably already shelling out for a smart phone, so the minute cost of some putty to adhere the X10's wired mic makes it nearly free. Early results are @ Mr Yesterday's wikiGong Sounds page; search on "Android."
Is this really all you need to replace $500 and up of dedicated recording rig? Of course not. But as a utility-belt tool we find it's pretty serviceable. It attracts no attention in airport security lines--which the PCM-D50, with its Geiger counter look and feel definitely does--and doubles as a handy phone. So you are likely to have it with you when the urge to record, say, the Eiffel Tower strikes. It's like a cheap little point-and-shoot camera for a photographer: better than nothing, and a low-risk, low-cost throw-down when you need one.
 The microphone challenge
Mic options are somewhat limited. Use the wired mic that comes with the phone or the mics built into the phone body. The X10 has two: one on the lower front for speaking into, one on the "rear"--the side, really--for speaker-phone mode when the phone is placed face down on a table.
When using the built-in mic, be prepared to hold still. Hands touching and clothing moving near the phone come through loud and clear, as do "macro" noises like jarring of the case. Set it on a solid surface and it will pick up vibration from surroundings as well as ambient sound, so use a cushion or rig a shock mount if you want clean environmental recordings (Remember, it's a phone: don't expect a tripod mount).
For contact miking, don't bother trying third-party mics. We recommend using the included piezo mic with putty to rig up a decent contact microphone. Be careful not to foul the little hole or depress the switch (used to "switch between your Music and Incoming Calls") with the putty! The button on the mic disables recording.
Note that when the phone's headset jack is occupied by the plug for the mic, the only available earphone jack is on the mic body itself; this design allows you to use a set of "earbuds" as a telephone headset, but it places the listener at the wrong end of the cable for a contact mic application. Since the X10 does not appear to support monitoring while recording, we recommend dispensing with earphones and using a recording app that has a good visual metering display (one of the reasons we like TapeMachine).
We've had next to no luck using any external device other than the one included with the phone, due to an active circuit used to detect button press on the mic. The mic appears to include an active component (may be as simple as a single transistor or diode), suggested by the asymmetrical resistance across ground and mic leads. Most iPhone gear just shorts mic to ground, but this phone appears to want a gentler touch. A quite audible, periodic, unipolar click appears on the recorded track if an iPhone-compatible mic is used.
We also strongly recommend you do not lose the headset as it is nearly impossible to replace at US carriers' outlets as of early 2011. The MH-700 upgrade Sony/Ericsson sells is unavailable in many countries, and it's merely pricey if you happen to be spending enough time in Sweden or the UK to mail order it for local delivery.Media:X10_Schertler_01.JPG.
So for those of you who are curious, or just choose to ignore our advice above, here's what we found.
You can see the bulky test setup in the photo. Much of the cord spaghetti resulted from adapting a ready-made four-conductor cable to separate the various signal paths. For this first test, we ended up using an AV cable for a Canon video camera. This put the various outputs on the "wrong" RCA plugs but allowed us to map the X10's jack pinout. Starting from the tip of the 2.5mm plug, the four conductors are:
< 1 | 2 | 3 | 4 ]--------- T R S1 S2
- Tip = left audio out
- Ring = right audio out
- Sleeve 1 = common/shield
- Sleeve 2 = mic signal in
The audible clicking heard using an iPhone mic is less noticeable with this heavier gear. It takes the phone a minute or more to detect a low-impedance source like this and then deactivate the built-in mics; in fact, we couldn't get standard dynamic mics like a Sure SM58 to work at all.
This test is also how we discovered the X10 doesn't support live monitoring with LivO. We suspect it is a hardware limitation affecting all software, or maybe an Android artifact. We verified the same behavior with TapeMachine.
 An Android field test
Listening to Jun Kaneko
The first hint that the X10 mic setup was troublesome turned up in Milan as we toured the Cimitero Monumentale interviewing angels. We picked up a lot of ambient noise--much of it quite high-frequency--and not much resonance. As soon as we were back in the States, we conducted two surveys in downtown San Jose with Jun Kaneko's ceramic Dangos outside the San Jose Repertory Theatre as our targets.
The differences between the X10 and Schertler mics are clear. The X10 is picking up ambient midrange and high-frequency noise almost exclusively, while the Schertler is picking up the sound of the resonant cavity itself. So, with the X10, you get more or less what you'll hear just listening around the sculptures, while the Schertler captures what you'll hear if you press your ear up against one of Kaneko's monoliths.
 Head to head
The Sony/Ericsson Xperia X10 is smaller and lighter than the dedicated machine, yet still boasts a 96k sampling application. Full-size image: Media:X10_vs_Sony_03.JPG
Where the X10 wins:
- Inexpensive (2011 prices):
- $99 with a 2-year contract, equivalent to many Android models
- $275 and up, unlocked without contract
- Mics included
- Built-in mics are sufficient for ambient recording
- An inexpensive wired piezo mic comes with the phone
- An extension mic cable (also included) gets piezo reach to about 1 metre
- Works with standard earphones
- Takes normal 2.5 mm stereo plugs
- Uses earbuds or airline headsets
- Supports larger powered headsets such as Bose noise-cancelers
- Supports WiFi and Bluetooth file transfer
- You're likely carrying a mobile anyway
Where the X10 loses:
- Proprietary mic circuit
- Xperia-compatible microphone headsets are pricey, hard to find
- Audible clicking on recordings made with iPhone compatible mics
- Not a good impedance match for dynamics we tested
- Poor piezo mic performance in contact mic application
- Optimized for voice pickup
- Shallow low-end frequency response
- High susceptibility to ambient and surface noise
- Monophonic recording only
- Gain control but no attenuation support in apps we tested
- A really loud environment leads unavoidably to clipping
- Handling noise
- No audio monitoring
- The headset appears inoperable while recording
- This may be a software issue; please advise if you know better
- Visual display compensates somewhat
 Bottom line
For recording ambient sound centered around one kHz (the spoken word), the X10/TapeMachine combo is lightweight and potent. Of course, if you can afford the space, extra weight, and higher price tag, the PCM-D50 is a far superior recorder. But the convenience of having recording capability with you at all times is hard to beat, now that apps and audio circuits are catching up. We're one step closer to the ubiquitous quality digital sound recording we're after! Keep a smart phone with a recording app handy.
If you are into contact microphone applications, however, the PCM-D50 paired with a real contact mic like the Schertler is a far superior setup. Until we discover another compatible mic, a workaround to enable traditional contact mics, or a suitable mod to the X10's wired mic, the X10 setup cannot be recommended for serious object acquisition. We'll keep this investigation open, and results will be posted here. But for now, the PCM-D50 and Schertler dominate our travel kit.
 Power to the people
The Schertler and other pickups are wonderful, but not inexpensive. For projects on a grander scale--but not necessarily a grand budget--cheaper alternatives may mean the difference between a successful mob action and a fizzle. In an upcoming article we will demonstrate how to improvise a contact microphone using really inexpensive tools such as the earbud headphones handed out on commercial airlines. These are even handy for the enthusiast stranded without a microphone or the right plug adapter. Stay tuned!
And how about a way to get that cheap, improvised transducing device (ITD) onto that equestrian statue's haunch from seven metres (yeah, metric since most of them are in Europe) below while standing in the middle of a busy traffic roundabout? If you have an idea, please contribute!
Software and other tools for planning, mapping, capturing, manipulating.
 Droid apps
There are several recording applications available for Android. They are such an integral part of the mobile-phone recording setup that we could compare them phone by phone. But in the interest of providing a bigger picture, we'll treat them as software and note which works better on each phone type as we figure that out. This is a rapidly changing scene so please join us and add your two cents.
So far, our favorite is Tape Machine. Even at a lowly 44.1 kHz, native files are clean (Following our Android 2.1 upgrade, we find TapeMachine can be set for a 96kHz sampling rate). TapeMachine also supports editing and conversion of audio in the phone, so you can BlueTooth or email smaller files.
Contenders, in descending order of first impressions and/or order downloaded:
- Our favorite Android recorder so far
- From Samalyse, Paris
- Price €3.99 as of January 2011. Free trial version available
- Monophonic recorder
- Record to microSD or SIM
- Gain setting: 0.0 to +20.0 dB
- Auto gain enable/disable
- Recording formats: WAV, MP3 (need to download CODEC)
- Multiple sample rates: 44.1 kHz, 96 kHz
- File conversion to: MP3, Ogg Vorbis, FLAC, AIFF
- It looks like more CODECs may be added
- Editing on-screen: Trim/cut, silence
 LivO Recorder Pro
- Runner-up and we purchased it as well
- From Mach+1 solutions
- Price US$3.99 as of January 2011. Free trial version LivO Recorder Lite
 RecForge Pro
- Nice little recorder app
- From Dje073
- Price US$5.36 as of January 2011. Free trial version RecForge Free
 Rehearsal Assistant
- We did a minimal trial run
- Developer has several apps designed to upload easily to SoundCloud
- From urbanSTEW
 Hertz, the WAV recorder
- Very basic capture to microSD card
- From dtg-android
 Please add more!
More details on our testing will be posted as our impressions ossify into opinions.
ccMixter exists to promote the Creative Commons and its approach to releasing content to the public domain. It's a fascinating subject with many legal and social implications. To get an idea of the background, we recommend Free Culture, Lawrence Lessig's discourse on US copyright law and its evolution from an individual artist's protection into a tool of corporate hegemony.
Now ccMixter is undergoing a transition from its volunteer roots into a new existence under ArtisTech Media. While onlookers wonder whether ccMixter's culture can survive any attempt at monetization, it's good to see the work survive. But the technology asset -- the ccHost application -- is open source and available to anyone with a little sweat equity and a web host. Read about the ccMixter Zeitgeist.
There is a lot more to be written on this subject, which we'll get to as soon as Jacob and I have got everything up and running. Frankly, there's still a lot of work to do! But be of good cheer because our success so far is proof that deep technical know-how is not a prerequisite to using this tool! (Which is a good thing, because the central idea here was never about becoming ace open source web 2.0 developers or administrators!) Meanwhile I'll be blogging occasional updates to the gongBlog.
This wiki portion of the site is implemented using WikiMedia's MediaWiki wiki engine. Again, deep technical know-how is not a prerequisite to using this tool!
You will want to work your way through learning wiki markup -- which is more limited than X/HTML and therefore has a much faster learning curve -- to produce good-looking articles. There's a lot of information available starting at MediaWiki. MediaWiki has the benefit of a huge contributor base since this is the same tool Wikipedia is implemented with.
MediWiki customization involves a bit of PHP dissection and occasional bits of HTML, but the default installation is extremely well-documented and easy to hack and learn. If you're an expert or just an enthusiast with time and energy to contribute and would like to dive into this aspect of the project, please contact us.
The wikiGong 1.0 front page and fixed content were originally authored using RealMac's RapidWeaver. We had a pretty text-based look then, representative of RapidWeaver-authored sites we've seen. It's a bit limited but gets the job done quickly without a lot of up-front investment (US $79 from RealMac but often available on sale from SmithMicro), and allows you to skip the hassle of learning a lot of HTML just to get a sidebar on the left-hand side of the page. If you start using it you'll start to recognize its templates are in use all around the web.
Hopefully, you like what you see. But we still thank RealMac for getting us started!
Useful things, increasingly available on the web. Find some of them on our Context page.