Internet media


OVER MANY YEARS I have built up a practice of taking audio recordings of talks and discussions at meetings, then editing and processing them into MP3 files that can be placed on the Web for streaming or downloading. It has always seemed a shame to me that so many organisations attract excellent speakers, whose lecture is listened to by a few score people at most, when it is so easy to use a little technology and skill to keep their words ‘in orbit round the globe’, for years and years after.

As a member of the Specialist Groups community of the British Computer Society, much of my recording work has been done for BCS groups and branches. I also regularly record at meetings of the International Society for Knowledge Organization (UK chapter), and in 2009 we replicated thus more than half the presentations at their first ISKO-UK international two-day conference.

One of my most recent audio-recording projects, which came out to the great satisfaction of all concerned, was a highly dynamic presentation on ‘Conquering the Imposter Syndrome’, given by executive coach Deena Gornick to a joint meeting of BCSWomen and Women in Technology. I edited together the choice bits of presentation with some interview segments between Deena and Women in Technology’s Maggie Berry, and you can now listen to the result from the WiT Web site. Incidentally, my ability to make this recording relied heavily on the technical capabilities of my new Marantz digital recorder, which is what this blog post is really about!

I also create explanatory and documentary videos, and a good quality audio recorder is very useful in preparing the narration track. Somewhat similar is a ‘slidecast’, Slideshare.net’s term for an audio narrative synchronised to a set of slides on their online hosting service. I wrote about my experience of making one of these a while back on this blog.

From tape and disk to solid-state

Olympus DS50 audio recorder

I’ve used a variety of tape and disk based audio recording devices in the last 15 years, including four MiniDisc machines, but in the last three years I have switched to devices with solid-state memory for storage. To transfer a 45-minute recording from MiniDisc or DAT tape to a computer for editing takes 45 minutes; but with these new-style devices, the recording is laid down in memory as a WAV or WMA or MP3 file, and is transferred to the computer in seconds, which is already an advantage.

I wrote about my ‘slidecasting’ experiment at a time when my main system was a well-designed but bulky and increasingly unreliable HHB MiniDisc recorder; my solid-state device, which I actually used for the slidecast, was a little handheld Olympus DS-50 voice recorder (a superior dictaphone, if you like).

HHB MiniDisc recorder with Røde studio mic in foreground and Sennheiser shotgun mic below.

The advantage of the HHB (when it worked) was its ability to take input from two independent external microphones, providing them with ‘phantom power’ if the mic technology needed it. As for the Olympus DS-50, it is a remarkably effective device for its size, and I always carry it about with me; but it can use only its own microphones, and because its internal memory is fixed at one gigabyte, it has to make use of a compressed audio data format (WMA) internally.

How things change! Recently, flash memory has become much cheaper, more capacious, and capable of faster data transfers. Compact digital cameras and camcorders now typically use one or other flavour of the Secure Digital memory card (‘SD card’) for storage, and today there is a crop of audio recorders which take the high-capacity version (SDHC). That is also true of the Olympus successors to my DS-50, such as the LS-10 which has a full-size SDHC slot. (If you fill up a card while on an assignment, you can always pop in another.)

Because SDHC storage is so capacious and speedy, many digital audio recorders now record uncompressed audio with a fidelity which in the past was associated only with DAT tape or hard disk recorders. The Olympus LS-10, for example, can record 24-bit WAV stereo files with a sampling frequency of 96 kHz.

A year with Zoom

Zoom H4

Zoom H4 is a popular digital recorder amongst musicians

In January 2009, I was on the look-out for a solid-state digital recorder which would be able to ‘inherit’ the full set of microphones from my now-abandoned HHB MiniDisc machine. I have two Røde large-diaphragm studio condenser microphones, which deliver outstanding clarity when properly mounted and positioned, plus a Sennheiser ‘short shotgun’ microphone which is extremely directional, and is my typical choice for video work. I also have a Sennheiser Evolution e85 handheld dynamic mic which is more suited to reportage situations.

I took advice from a Soho shop for musicians, which in retrospect was a mistake. They convinced me that the Zoom H4 recorder was a world-beating favourite. I bought one (but not from them; Studiospares is always cheaper!) and started to experiment.

During 2009 I made many fine recordings with the Zoom H4: for example, the ISKO-UK conference series referred to above. I have never used the Zoom’s own built-in microphones, always plugging my own mics in via XLR shielded cabling. (The XLR cable format has a third pin to carry phantom power out to the mic, and the shielding prevents picking up radio interference from the local taxi company or, as is more likely these days, someone’s mobile phone hunting for a signal.)

Zoom H4 shortcomings

It wasn’t long before I discovered four annoying shortcomings of the Zoom H4:

  • Feeble pre-amps. This is why asking a music shop for advice was such a bad idea. The Zoom H4 is a great favourite with bands who want a convenient small device with which to record their practice sessions, and those guys are LOUD. They don’t need the microphone signal to be boosted much, whereas someone recording meetings really needs substantially greater pre-amplification of the incoming signal.
  • Greedy for power. The Zoom H4 can be powered from a pair of AA batteries, but it drains them very quickly, especially if you use NiMH rechargeables. That might be OK for recording four-minute songs, but not for two-hour meetings.
  • Dreadful interface. I have used the Zoom H4 in lectures as an example of the difference between ‘functionality’ and ‘usability’. Its fiddly switches and jog dial, and the tiny LCD display with anaemic backlighting, make it a real pain for an older and somewhat long-sighted person like me to work with.
  • Not built for ‘the field’. There’s no way to attach a carrying strap to the Zoom H4, it doesn’t sit securely on a table, and the build is rather fragile.

Using an AudioBuddy pre-amplifier to compensate for the poor pre-amps in the Zoom H4 itself

I was able to solve the first two problems (for example when recording for ISKO) by plugging my microphones into a separate portable ‘Audio Buddy’ pre-amplifier, and powering each of these devices from their power packs, plugged into mains power. Then I would take line-level input from the Audio Buddy into the audio recorder.

This set-up has the added benefit that the Audio Buddy has a separate, easily adjusted gain control knob for each input channel. My ‘ideal’ mic set-up for a lecture is to put a quality Røde condenser mic near the speaker, on the ‘main’ channel, and keep the short shotgun mic beside me (suspended in a Rycote hand-held shockmount) on the second channel. I keep the gain on the secondary channel turned down until I need the shotgun mic to pick up questions from the floor, or to re-inforce the primary audio if the speaker wanders away from the microphone.

So, I had a workable solution. But it was annoying to find that the Zoom H4 was, in effect, only usable when I had access to mains power, and it also necessitated dragging extra gear along to each meeting where I was invited to record.

Twice or thrice as nice: Marantz PMD661

These experiences prompted me to do my research more carefully this time, and to pay particular credence to the opinions of field recordists and radio journalists. My choice at the beginning of this year was a Marantz PMD661 recorder, and my experiences with this machine have all been positive so far.

Marantz PMD661 recorder, belt-mounted

Marantz PMD661, suspended from my belt with an Arno strap. The cable from my dynamic interview mic is plugged into the ‘bottom’ of the device, and I am adjusting the gain knob.

Compared to the Zoom, the Marantz is more than twice as expensive, twice the volume, and perhaps three times the weight; but even so, that’s quite compact, smaller and much lighter than a digital SLR camera. The Marantz is built substantially, and the control surfaces are laid out ergonomically for two main modes of use: horizontally, with the device set on a table, or suspended vertically on a shoulder-strap through the strong metal connection loops. Latterly I’ve been keeping an Arno buckle-strap through one of the loops, and clipping that to a carabiner on my belt.

On the broader control surface (the ‘top’ in horizontal use mode), there is a large legible OLED multifunction display, and coloured LEDs signal the recording status and the sound levels of the two recording channels: all very useful when recording in low light levels. The Record, Record-Pause and Stop buttons are all comfortably thumb-sized. The narrower control surface, which is the ‘top’ when you have the Marantz at your side, carries the quarter-inch jack socket for headphone monitoring, the headphone volume control, and concentric recording-level adjustment dials for the two channels. You can operate these by feel alone.

Sound in and out

Whichever way you use the Marantz PMD661, when its interface is oriented towards you, the XLR sockets are at the side facing away from you. I can understand why the Zoom is configured the other way round, but it doesn’t make for convenience in the field.

In addition to the XLR inputs, which can be set as ‘line’ or ‘mic’ or ‘mic with phantom power’, there is also a competent pair of inbuilt mics, a ‘digital in’ port (electrical S/PDIF), and a secondary ‘line-in’ port for a 3.5 mm stereo microjack. I use this last when recording from my DAB radio.

And here is the all-important news: the microphone pre-amps in the Marantz are excellent! They are so powerful that I have been able to bring my voice-coil dynamic interview mic back into use. I’m also able to use my favourite Beyer DT-100 monitoring headphones: the Marantz headphone amp is strong enough to overcome their 100-ohm resistance.

Unlike the Zoom H4, the Marantz PMD661 can output through an inbuilt stereo pair of speakers. They’re not wonderful, but if you want to review an interview with your interviewee, they’re dead handy.

Power with intelligence

As for the power situation, the Marantz takes four AA cells, either alkaline or NiMH (nickel-metal hydride). I use the new-style low self-discharge NiMH type, rated at 2300 mAh, and I can get more than two hours’ continuous recording (with phantom power) out of them. With alkalines, I’m good to go for over five hours free of mains power.

In the settings menus, you can tell the Marantz which of these power options you are using – a feature I’ve not seen on any other electronic device. The importance of this is that NiMH cells start delivering power at 1.4V, but rapidly drop to 1.25V at 10% discharge, then maintain that voltage for most of the discharge period. Many devices (e.g. my DAB radio) interpret this low-voltage reading from NiHM cells as a ‘these batteries are flat’ signal, which ain’t true. Good thinking, Marantz!

To record a conference ‘properly’, I’d still lug my Røde mic and mic stands, use mains power and even include the Audio Buddy in the loop; but now with the Marantz I have the additional capability (a) to ‘go walkabout’ at an event, which proved necessary for the Deena Gornick recording and (b) to keep a lightweight recording kit on me at all times, such as illustrated in the photos, in case something comes my way ‘serendipitously’.

Two takes on time

Finally, I must touch on one very peculiar ‘feature’ of the Zoom H4. One one or two occasions I have had a need to record the video of an event, but also capture the audio on a separate audio recorder (for example, one occasion when my filming position was at the very back of a lecture theatre and I wasn’t able to run a long cable from there to where I wanted the microphone to be).

When I tried that with the Zoom H4 as my audio recorder, I found that its ‘sense of time’ drifted away from that of the video camera, making it impossible to synchronise the two recordings. Checking on the Web, I find that this is a well-known and much criticised feature of the Zoom H4. Incidentally there is now a new Zoom recorder, the H4a, which has vastly improved interface and control surface; but whether this particular glitch is fixed or not, I don’t know.

Three days ago I was filming at a meeting in a London hotel, and for a slightly different reason this time I was again recording the audio separately, this time to the Marantz. I’m pleased to say that I was able to synchronise the audio to the video perfectly this time, using the Marantz audio and throwing away the camera audio. Another thumbs-up for the PMD661!

At a recent social media networking meeting I did hear accusations of unreliability directed against the Marantz. Maybe I’ve just been lucky. Or maybe the critic was referring to the predecessor, the PMD660, which did draw a lot of flak, for example for the ‘noisiness’ of its pre-amp circuits. The PMD661 is a substantially redesigned machine drawing on the lessons learned from its predecessor, which I guess reinforces the message that you are generally better off not buying Version One of anything!

IN MY LAST BLOG ENTRY I described being at the BarCamp5 Spillover event held at the BCS London meeting rooms. On 9th October it will be my turn (with colleagues) to run an event in the same location: the MetaKnowledge Mash-up 2.0 gathering [But see NOTE below], organised by KIDMM and ISKO-UK and with the focus Making and Organising Knowledge in Communities.

(A word of explanation: KIDMM is a discussion community around issues of Knowledge, Information, Data and Metadata Management — its roots are in the British Computer Society — and ISKO-UK is the UK chapter of the International Society for Knowledge Organization. I co-ordinate the activities of KIDMM on a voluntary basis.)

Plastic poker chips being used to ‘rate’ the importance of topics generated on cards by group members, in a discussion about computers and climate change.

Plastic poker chips being used to ‘rate’ the importance of topics generated on cards by group members, in a discussion about computers and climate change.

The instructions for BarCamp said ‘Come with something you want to talk about,’ and I brought along with me a concern about the best way to conduct small group exercises on the afternoon of the 9th. People there will be seated in groups of up to eight around tables, an arrangement which affords a surface for a card-sorting exercise.

In the BarCamp discussion which I led, I explained how cardsorting works and how it can be used to understand how people group ‘things’, be they ideas, features of a product, whatever. In information architecture and product design enterprises, letting a representative group of users sort cards can help clarify what people expect of or hope from a product or service. There’s a variant called ‘divide the dollar’ which I read about through Uzanto’s Mindcanvas site, which offers these ‘Game-like Elicitation Methods’ (GEMs) on-line. In this, each participant is given a number of coins or chips and asked to distribute them across a set of topic cards to indicate in quite a subtle way the degree of value attached by that person to each.

What has this to do with a KIDMM/ISKO conference? Well, in considering ‘making and organising knowledge in communities’ we will be hearing case-studies from a number of organisations who are using electronic tools to enable long-term and long-distance discussion and collaboration within their communities, with the aim of accumulating and organising knowledge. Tools like email lists, bulletin boards, blogs, wikis, social networking sites, and online media repositories for documents, audio files or video — in addition of course to face to face gatherings and designed-for-print publications. Which of these approaches seem to hold out most advantages, and how might they be combined? The workshop session is when we can deliberate on this, and a cardsort is my proposed mechanism for this.

Hopefully, all participants will appreciate the opportunity this exercise will afford to sift through the approaches we’ve heard of through the day, and brainstorm a few more. And for the KIDMM community, this foray into ‘requirements elicitation’ has another benefit — with the assistance of a final-year software engineering student, Susan Payne of De Montfort University, we are embarking on our own venture into online community. In the next eight months, Susan will be writing a custom web application based on a CMS (content management system), designed to match the needs of knowledge communities such as KIDMM.

If you’re interested in learning more about cardsorting and other user requirement elicitation strategies, I have written up a five-page account of my BarCamp5 session — how I presented the topic and how people responded to it — which is available for download as a PDF file. [But see NOTE below]

Also available for download is my preconference paper: a literature and concept review on knowledge management, communities of practice and approaches to the evaluation of online community toolkits. [But see NOTE below]

NOTE: The domain kidmm.org has been kidnapped! Following KIDMM-hosted links will currently take to a Web site about baby clothes and things. Apologies while this gets sorted out. It is partly due to the incompetence of my ISP, Adept (should be Inept?) Hosting, who are also currently ignoring calls for support. [11 Oct 2008]

Rashmi Sinha

Rashmi Sinha

SINCE I READ an interview with Rashmi Sinha in the Information Design Journal, I’ve followed her enterprises with great interest. Most recently she’s been involved with setting up and running SlideShare.net, a place where you can upload your presentation slides — be they PowerPoint, OpenOffice or PDF — and share them either privately with an invited group or with the world.

Now, ordinarily that facility wouldn’t appeal to me. You see, when I prepare slides to accompany a talk, I don’t put much text on them. I believe that we’ve only got one language-processing centre in our brain and it has to cope with making sense of words whether they come in through the eye or the ear. So, making people read and listen to you at the same time is not a smart thing to do. A lot of the time, my slides just have pictures on them.

But I did get interested when I heard about ‘slidecasting’. That’s SlideShare’s term for linking an audio file to your slides and synchronising the turning of the slides to specific points in the audio file. It’s hardly a new idea, in fact it is reminiscent of the old slide-tape shows, but it could be an excellent way to ‘broadcast’ ideas over the Internet, and I thought I should give it a go.

The opportunity arose. On 17th September I am due to speak at an event on climate change organised by the British Computer Society’s Sussex Branch. I have to fit into a tight time-slot and though I usually speak from a handful of notes, this time I thought I should script my talk and time it. So here I had the perfect test case for slidecasting!

I don’t do PowerPoint, so I made my slides in Adobe InDesign CS3 by creating a document the pages of which measure 1024 points wide and 768 points high. Images were prepared in Illustrator and Photoshop. Finally, I exported the 42 pages as a PDF file, and this is what I uploaded to my SlideShare account.

HHB MiniDisc recorder with Røde studio mic in foreground and Sennheiser shotgun mic below.

HHB MiniDisc recorder with Røde studio mic in foreground and Sennheiser shotgun mic below.

Recording the audio

Audio is more of a challenge, but I quite frequently record conferences for the BCS and other organisations, and I also record voiceover narrative for video productions. My preferred kit for this purpose is an HHB professional MiniDisc recorder and a Røde condenser studio microphone. However, at the moment the HHB is sick, so that was out of the question.

Olympus DS50 audio recorder

Olympus DS50 audio recorder

My back-up recorder is very small indeed. It’s an Olympus DS-50. It has three sensitivity settings marked Dict, Conf and Lecture. The stereo microphone that plugs into it is actually quite good quality, considering. The audio is saved into the solid-state memory as Windows Media Audio (WMA) files, and there are five compressions one can choose from, and I always go for the most gentle.

So I took my script and chose the bedroom as the quieter place to record: it doesn’t face onto the river with all its traffic. I set the Olympus on Dictation-mode sensitivity to suppress as much background noise as possible and arranged a place for it quite close to my mouth, and made my recording. The thing to do is, if you fluff your lines or a magpie decides to add an accompaniment, you just repeat that paragraph and deal with it in the editing.

The Olympus attaches to the Macintosh as if it were an external USB drive and you copy the recording file across. Macs don’t much like WMA files but I’d bought Patrice Bensoussan’s EasyWMA audio converter plug-in for QuickTime ($10) and converted the file to AIFF for editing. I use Apple’s Soundtrack Pro for editing, chopping out the out-takes and suppressing intakes of breath. I thought the output from the Olympus sounded a bit ‘tinny’; the solution was to use the ‘Fat EQ’ filter to boost the lower frequencies until it sounded like me again.

I saved the result as mono AIFF and then took it into iTunes to convert it to MP3. My standard podcast settings use a data rate maximum of 56 kbps, 16 bits of precision, Variable Bit Rate and best quality conversion. The 23 minutes of speech came out slightly less than 10 MB.

Uploading and synchronising

SlideShare.net are quite generous in the size of presentations you can upload – up to 100 MB — but for now at least they won’t host your audio. You have to find somewhere from which audio will stream, and they recommend placing it on The Internet Archive, which is what I did (I already had an account there — it’s free to use, as is SlideShare.) Once you have copied the URL where your sound file sits, you paste that into a field on SlideShare, and the slides and audio are connected.

click image to enlarge!

SlideShare’s synchronisation tool: click image to enlarge!

I had feared that the synchronising of the slide-turns to the appropriate places in the talk would be tricky, and it was the most difficult part, but I soon got the hang of it. Considering that you are working with files on two different servers on the other side of the world, it’s quite amazing that it works at all! If you click on the thumbnail image of the screen shot, you’ll see my edit in progress. The slides ‘slide’ along in the upper channel, and the synchronisation workspace shows the waveform of the audio, which is something I feel very comfortable working with. The Audio Selector at the bottom wasn’t immediately intuitive to me; you slide it along to reveal another bit of the audio further on.

The red line in the Workspace is the ‘playhead’ and you play and pause the audio to find the sync points. I kept trying to stop and start the audio by hitting the space-bar because that’s what you do in iTunes, QuickTime and Soundtrack Pro, but not here! The process is a bit clumsy, and due to the latency across the Internet it’s a bit unresponsive at times. As you move the ‘slide x end’ line to where you want it, the next slide asks you to ‘Select this slide to synchronise’ and when you click on it, it dumps a new blue line close to the previous one. They you play along until you find the next sync spot, drag the rightmost blue line to that spot, and repeat.

It’s good. It works. It’s quite impressive. It’s all done with Flash technology. And it’s here (my first slidecast, I mean). It works full screen too, so you can really see detail if you want. My main gripe is that as my slidecast makes progress, the slides arrive later and later after the points that I had designated for synchronisation. I hypothesise that this may be because my slides have a great deal of graphic content?