Smartphone Audio Recording – Part 3: Setup by Nigel Rumsey

A diagram showing smartphone connection to lav microphone So now you have your smartphone, microphone, recording app, some earbuds and you're ready to make amazing audio - how do you do that? The first thing to say is the scope of this post is dealing with the recording technique, not interview technique I've a lot to learn in that area - I will give some links to further information at the end.

In case you haven’t read the earlier posts: I'm not an audio expert, I'm in the early stages of learning how to do this. As much as anything this is a good way for me to consolidate what I've learnt. If you disagree with what I'm saying please chip in, I'm always interested to hear from you.

Before You Set Off

Battery: It may sound obvious but make sure your phone battery is fully charged. Also bring your charging lead with you, if you can record while plugged into mains power then even better. If you’re interested in battery backup this review by Martin Shakeshaft may be helpful.

Memory: check you have enough space in your phone's memory for your recording. Recording in WAV format is going to use approximately 10MB per minute. This is where Android users have a huge advantage, many android phones will except a mini or micro-SD card to expand the memory beyond what's built-in to the phone. I generally need to delete some music from my iPhone before recording to ensure there's enough space.

App Settings

There are many very heavy tomes on this subject but here's my brief layman's guide.

File format: Your recording app can save the file in a number of formats. Keeping it simple there are two choices you’re interested in (1) WAV: a lossless format that will give you the best quality and a greater flexibility in the edit. The downside it takes more storage space than (2) MP3: a lossy format, it uses significantly less space and playable on just about every device. Here's an interesting post that gives more info.

Bitrate and quality: The other things your app is going to ask you to set are the sampling rate, which should be 44,100 khz and the bit depth which will be 16 bit. If you want to know more there’s a good article in Wikipedia. This video does a great job of explaining what the sampling rate and bit depth actually are.

The Setup

If you're using the Rode SmartLAV+ and the Rode SC6 adaptor the image above is how your setup should look. If you're using Rode equipment the TRRS plugs are grey and the TRS plugs are black - if that means nothing to you look back at the previous post.

If you only have a Lav microphone - without the SC6 adaptor - you can still record but you won't be able to monitor your recording - which could be considered the audio equivalent of walking a tightrope without a safety net. The key thing would be to monitor your levels so you will at least know a signal is reaching the phone, if not how sweet is sounds.

Before Recording Put your phone in airplane mode. If it rings or you get a text during the recording your recording will be interrupted - from this point on your 'phone' is a recording device only.

The lav needs to be clipped to the interviewee's blouse or shirt about 150mm below their chin - I don't expect you to get a tape measure out but that's roughly what you're aiming for. If possible you want to clip the microphone so that it's not rubbing on the interviewee's clothing if they move around a little - not always easy. This video gives some tips on positioning the Lav, it also shows how much noise brushing the mic during a recording can make.

[embed][/embed] Levels: While recording you're aiming for a high enough level so that you can clearly hear everything you subject is saying, while avoiding any peaking or distortion. The rule-of-thumb seems to have been to aim for an average level of -12db. It's definitely not easy on these small displays to get an accurate idea of the level. It's best to practice a few times so you know the level on the app you're unsung that's going to give you results you're happy with.

a screen shot from Android app Field Recorder

A screen shot from iPhone app Voice Record Pro











Try to get your interviewee chatting while you're setting up apart from anything else if they're a little nervous this will tend to put them at ease. Check you're levels aren't going it to the red. If you're unsure it's best to err on the side of caution. It's easy to boost the level a bit in the edit, however once you've got clipping because the level's too high there isn't much you can do. For more info check out this Transom article.

Once you've finished recording save a copy of the file to a cloud service like Dropbox or GoogleDrive. You're probably going to want to get to wi-fi zone before you do that or you're going to chomp through your data allowance pretty quickly. The important thing is that you don’t start editing until you’ve made a copy which should, ideally, be off of your phone.

As I've said before I'm skimming the surface of what you can do - my aim is to hopefully inspire you to give this a go. The last post in this series, will give a list of information and further resources. However if you're keen to know more now is the place to go. Transom has a fantastic archive of posts on all the subjects I've covered and way more. Transom is also home to the truly inspiring HowSound podcast, it really is essential listening for any inspiring radio producer.

Next week I'll be looking at a few mics you might be interested in if you want to go hand-held and then week 5 will be a wrap up and further resources post.

Part 1: Getting Started Part 2: What you need (Budget)

Enjoy your week and don't forget to listen to some great radio.

Smartphone Audio – Part 2: What you need (budget) by Nigel Rumsey

iPhone 5 with lavalier microphoneIn the first part of this series I give an overview of how to start recording audio on your smartphone and the things you need to tweak to get better quality. Here in part 2 what I found I needed to buy and why. Again with the disclaimer: I'm not an audio expert, I'm in the early stages of learning how to do this. As much as anything this is a good way for me to consolidate what I've learnt. If you disagree with what I'm saying please chip in, I'm always interested to hear from you.

If you don't come from an audio background, as I don't, it's easy to think 'if I have great images the audio doesn't need to be that good, the images will show though'. I'm afraid to say that isn't the case. If you play crappy audio behind your stunning images people will turn off pretty quickly. If you're recording audio only, then you want it to be the sole focus of your audience's interest so it needs to be really good.

So how do we get good audio? There's obviously technique involved but before that you need the tools to do the job and that's today's subject

The Low Cost Smartphone Audio Shopping List


Getting good audio starts with the microphone. In this post we're not looking for the best-of-the-best, we're after what a beginner needs to get started. You have three options :

  • a microphone you fit onto the phone so the phone and the mic form a single unit
  • a hand held mic (we'll talk about these in a later post)
  • or a lavalier (lapel) mic.

To start with I choose the lapel mic because I could get good quality audio fairly inexpensively, they're small (very small) and I could plug one straight into my phone. After some very extensive Googling, a lot of reading and even more listening I settled on the Rode SmartLav+ lavalier microphone - £43.99. * Be careful not to get the Rode SmartLav (without the plus) which is the older version and apparently not so great.*

Smartphone to Microphone Connections

A TRRS connector for plugging a microphone into a smartphone

We need to take a moment and talk about 3.5mm audio jacks (exciting ehh!). It may be a surprise to you to know that they come in three flavours. If you're interested there's a whole load of information in this Wikipedia post. But what you need to know is that microphones that plug directly into smartphones need a TRRS connector. TRRS isn't suitable for plugging into non-smartphone digital recording devices - although you can get an adaptor.

Recording Apps

iPhone: Voice Record Pro Free (there is an in-app purchase to go to the ad free version). I've also used the free Rode app, but I don't like it as much as Voice Record Pro. Android: RecForge II - Audio Recorder Free and Field Recorder £3.49 both get good reviews.

So why are these better than the built-in app? It's a good question. The apps above will allow you to save in .WAV format, record at different qualities, save directly to a host of online backup services and more!

I have an iPhone and used Voice Record Pro. The choice of app wasn't nearly as clear-cut as for the SmartLav+. For every recording app I looked, and trust me I looked at a few, there are reports of a disaster that someone's had. Voice Record Pro seemed more reliable than most and to date it's performed well for me. I don't have an Android phone so I haven't been able to test RecForge II or Field Recorder. However they have been recommended by people who've used them extensively.

Monitoring your Recording

a dual microphone and headphone adaptor for smartphones

While you're recording it's vital to know the precious moments you're hearing are also being heard by your smartphone. If you have a dedicated digital recorder it will generally have a headphone jack so you can monitor exactly what the device is hearing. Your smartphone only has one 3.5mm jack, so the good folks at Rode have created this neat little adaptor (£10.99) which allows you to plug your headphones and two microphones in at the same time.

It is worth noting that what you'll be listening to is only what the microphone(s) are hearing the signal hasn't yet arrived at the smartphone. What's the difference? Well, Voice Record Pro - for example - has a 'monitor levels' option where the device is pickup up the signal displaying the levels but not actually recording. In your earbuds that's not going to sound any different from when you're actually recording. Be aware - check your phone is recording before you start the interview.

Headphones / Earbuds

Ideally you'll be monitoring your recording with some good quality headphones (more to follow in later weeks) however at this stage for our 'budget getting started' setup your regular earbuds will do just fine. I've never got on with the Apple earbuds so I buy these, they're far from the best, but bang-for-your-buck I think they're good value.

Optional Extra: The only other thing I bought was an extension lead for the microphone. Rode do offer one but I just bought this cheaper version (£3.50) and the quality is fine. Remember if you're looking for one you need 'TRRS male to female'.

How will it sound?

This was recorded with the setup detailed above and for a budget setup recorded on an iPhone I'm happy with the quality.

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The Total Bill

So far, assuming you already have some earbuds, you will have spent at most: - Rode SmartLav+ : £43.99 - Rode SC6 adaptor : £10.99 - Apps : Free to £3.49 - Extension cable : £3.50 Total : £61.97 Which is not nothing but in the big scheme of things not bad to get good audio.

Next time: Recording technique. What I've learnt so far, links to more information etc. Don't forget go listen to good radio while you're waiting.

Part 1: Getting Started

Enjoy your week!

Smartphone Audio - Part 1: Getting Started by Nigel Rumsey

iPhone 5 I've talked before about how listening to documentary radio as inspired my photography and inspired me to look at other methods of digital story telling. In this post I recommended several podcasts that should do the trick for you.

Once you've got all this pent-up inspiration it's time to get out and actually do some thing about it. So today I thought it might be useful to talk about the practicalities of getting started. It's important to say I'm not an audio expert, I'm in the early stages of learning how to do this. As much as anything this is a good way for me to consolidate what I've learnt so far. If you disagree with what I'm saying please chip in, I'm always interested to hear from you. I'm writing this as an iPhone 5 user, but the majority of what I say will be applicable to any smartphone.

I have a tendency to launch off into huge blog posts and I know that's not what most people want, so I'm going to break this up into small chunks. Today the 'getting started overview'.

If you have a smartphone in your pocket technically you have everything you need to record, edit and publish audio - it's worth taking a second to realise quite how amazing that is. A few years ago the equipment to do that would have cost the equivalent of several thousand pounds. Granted smartphones aren't cheap however the barrier to entry has never been lower. That done - if you want to make the best of what your smartphone can offer a couple of tweaks and a relatively small investment will enhance your audio no end.

iPhone 5 microphone location


If you're a photographer you will likely have had drummed into you the benefits of separating your camera from your flash. Think of your microphone in the same way. 1. The smartphone mic is principally designed for picking up your voice while you're talking on the phone. Therefore it's designed to be used very close to your mouth. Which is not where you're likely to be holding your mic if you're recording something or someone other than yourself. 2. Every time you move your hand on the phone, brush it up against something or change a setting you'll probably capture that noise on the recording. 3. While recording you should be checking the recording levels, if you're holding the phone near someone's chin you're not going to be able to do that very easily.

So let's get the mic off of the phone.

Recording Apps

Your built in app is great for what it's designed for - recording you singing drunken versions of Bohemian Rhapsody important voice memos at work. What it isn't designed for is allowing you to record in AAC format, adjust the levels, change the quality, trim the recording or a host of other things you may need. There are plenty of low cost, or even free, apps for both IOS and Android that'll give you all the features you need, and some.

Monitoring What You're Recording

As you're recording your world exclusive interview with Elvis - who is, as I've always thought, alive and singing nightly at a 24 hour diner in Portland - it'd be quite nice to know that what he's saying is actually being picked up by the mic. A small cheap(ish) adapter and a set of earbuds will allow you to do that.

That's the brief overview. There's a lot more to come. If you only have the phone at the moment don't let what I've said stop you going out recording something or someone. If you're careful and hold the phone near your interviewee's chin it'll do a fair job and it's far better than not getting the interview at all.

Next Time: I'll tell you what I choose, why and whether I made the right choices. The next post should be up by next weekend. If you don't want to bother checking back in there's a sign up by mail thingy on the right-hand side.

Enjoy your week.