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[Mara]

I'm hoping someone will be able to offer advice or point me in the right direction. I know my questions will seem silly to most of you, but I'm somewhat new and would like to improve my results and get the best recordings I possibly can.

On my last visit to WDW, I took my digital voice recorder and bought a telephone pickup to attempt some induction recordings. The results were decent in my opinion considering the recorder is a pretty simple device, meaning there aren't many options or settings to tinker with. Also, the highest mp3 rate it is capable of recording is only 192kbps, which leaves something to be desired.

So, before my next trip, I would like to get a new recorder but am unsure exactly what to look for. I've visited several sites that sell them, but it's a little overwhelming not knowing anything about them. Would anybody here mind sharing what recorders you use? Does it take a lot of understanding and practice to get good results?

Here are a few specific questions:

1. If the recorder has the option to record in WAV format, is that the way to go vs. 320kpbs mp3s? Are WAV files able to be converted to mp3s (basically, is WAV format the higher quality of the two?)?

2. I'm under the impression that no matter what type of recorder you use, if you use a telephone pickup to get an induction recording, then the recording will be mono. Is this correct? If so, is there a way to make the recording "stereo"? I've noticed that some of the induction recordings I've downloaded from here seem to be stereo recordings - is this just the same file being copied to the right channel? If so, how would I be able to do that?

3. With my current voice recorder, when I make an induction recording, I don't really have any options to play with. I've seen "setting the levels" discussed on other posts here and also on reviews of more expensive recorders. What does that mean, how is it done, and is it difficult to get the levels right?

Thanks in advance for any help or advice.

[pixelated]

I'm going to use some audiophile jargon since I'm bit pressed for time.  If you don't understand something I wrote, please ask for clarification.

1.  320 kbps MP3 files sound pretty darn good but they use lossy compression which means there is still some loss of sound quality compared to the original source.  That's because lossy compression means you're permanently throwing away some audio information in order to get a smaller file.  PCM WAV files are uncompressed so there is no loss of quality due to compression.  If you compare the audio spectrogram/sonogram of a CD track ripped as a 320 kbps MP3 to a WAV version of the same track, you'll see high frequency rolloff in the MP3 version.  If you have a recorder that can record PCM WAV, you might as well record in a higher quality format.

Yes, you can convert from WAV to MP3 or any other formats supported by the editing/conversion software you're using.

2.  A telephone pickup can record one sound source so the result will be mono, similar to how a "normal" audio mic records in mono.  Stereo audio mics have two microphones in them so that's how they are able to record in stereo.  So it follows that if you want to do a stereo induction recording, you'll need two induction pickups/mics.  If you want to convert a mono recording so it "sounds" stereo, there's a simple technique you can use in audio editing software but I've never tried it myself.
Turn a mono track into rich stereo
http://www.benvesco.com/blog/mixing/2008/turn-a-mono-track-into-rich-stereo/

3. Simple digital voice recorders usually have automatic record level controls because they are meant to record people talking (as their name implies).  It's important to get what someone said, whether they are whispering or shouting .  But when recording music, having a consistent volume level detracts from the listening experience.  If the composer/performer wanted the louder parts softer and the quieter parts louder, they would have performed it that way  .  Automatic record level is a form of compression (it's compressing the volume level of the audio) and yep, this type of compression is also undesireable.

How to set proper record levels... your recorder should have a legible VU meter so you can see the sound levels of what you're recording.  You never want the record level to go past 0 dB because that means the sound is too loud for the recorder to record properly.  That results in "clipping"; it's called that because if you look at that waveform in an audio editor, the tops of the waveform envelope above 0 db are missing and are just flat lines like they had been cut with scissors.  If you listen to clipped audio, it'll sound distorted because of the missing audio.

So to avoid clipping the audio, you set the record level so the "average" sound level is well below 0 dB.  That's called leaving "headroom" in your recording so louder parts of the audio won't be clipped.  I usually go for what the recorder manufacturer suggests, which is -12 dB.

What's the "average" sound level?  You'll have to monitor the audio with the recorder's VU meter for at least a few minutes to see how loud (or soft) the audio is.  You should also monitor the audio while while recording with headphones or earbuds so if a very loud section of audio is played that results in distortion/clipping, you'll be able to notice it and know that it happened before you leave the Park.  If you're recording a loop, you lower the record level to what you think/hope is a safe level for that section of audio and keep recording so you get a non-clipped version of that audio when it is played again.

[ebbelein]

Let me add just a small bit to pixelated´s statement:

Technically there is no way to make a mono file "real stereo", because you would have to "divide" the instrument groups likes strings / horns /guitars etc. to the seperate channels "left" and "right" - which is impossible, since you can´t accurately filter the instruments out of the mono mix and pan it left and right. The way described in pixelated link only makes a mono file "sound" more like stereo, but IMHO as soon as you listen with headphones it sounds quite a mess... I personally stick to the mono versions...

[eyore]

I'd add just one more thing. For an induction recording the position of the mic on the speaker is really important. A fraction of an inch can mean the difference between  a poor and a great recording as does the quality of the sound from the speaker (rubbish in, rubbish out). Unfortunately there isn't a foolproof method to know you have hit the right spot although if you can listen with an earphone you can get a good idea of where the strongest signal is so take a few minutes to site the mic before recording (and watch it doesn't move - many use sticky pads or tape to hold the mic in place).
As Pixelated says, record in wav if possible (most recorders have a decent enough memory and memory cards are not that expensive). You can always convert to mp3 for your own use later if you need to while keeping the "master" in lossless. It's disappointing to find you have got everything right but you recorded it at a low bitrate. 

I use the Zoom H2 which is a reasonable price and does the job (I believe their new version is even better).

[pixelated]

The precision of the induction pickup location is dependent on the strength and overall shape of the magnetic field coming from the speaker's electromagnetic coil.  With some speakers, you just need the pickup to be somewhere near the speaker and you'll get a decent signal.  With others, it is as eyore says, the pickup must be on a certain "sweet spot" to get a good signal.  Generally, louder audio volumes result in larger & broader magnetic fields, which in turn create a bigger sweet spot.

Since you can't see magnetic fields, you need to roughly map them out with the induction pickup and recorder by listening to the signal through headphones while moving the pickup around on the surface of speaker and/or the space around the speaker.  If the sweet spot is large enough, the pickup does not even have to touch the speaker.  This comes in handy with speakers that are out of reach .

[FourParks]

[deleted]

[Mara]

Thanks to all who replied. The information provided is a big help, and I especially appreciate pixelated taking the time to break it down in a way that's easy to understand.

I'll be doing some more research and will undoubtedly have more questions in the future. For now, here are a couple more:

1. When you guys make an induction recording, do you typically use one or two pickups? Most of the induction recordings shared here sound great to me, so I'm trying to get an understanding of the set up and different tools you all use. Also, are some pickups better than others? I bought mine from Radio Shack, but if there are better options, I would like to upgrade.

2. After looking around tonight, it looks like this hobby could get expensive (at least more than I had anticipated). Some of the recorders that appear to be in my price range are the Tascam DR-05, Tascam DR-40, and Roland R-05. From what I can gather, these are probably at the lower end of recorders. Does anyone know which, if any, will provide decent results (or recommend something better in the $200 and under price range)?

Thanks again everyone.

[772pilot]

Yes, typically just one. However, there are cases in which using 2 pickups is desirable such as when a speaker enclosure has a tweeter and subwoofer separated by some distance (One pickup for each). When mixed together, the resulting sound will be much richer.

Take a look at the Sony PCM-M10 (my recorder of choice). Excellent pre-amp for boosting those low input levels without introducing too much noise.

[pixelated]

Take a look at the Sony PCM-M10 (my recorder of choice). Excellent pre-amp for boosting those low input levels without introducing too much noise.

Yep, the Sony line of linear PCM digital recorders are very, very good.

I forgot to mention in the part about mapping the speaker's magnetic field is that you should move the induction pickup all around the speaker.  I.e., not just the front but the top, bottom, sides and back.  Just because the sound comes out the front doesn't necessarily mean that the best location will be in the front.  The front *is* usually a good spot but not always .

[eyore]

Recording with two pickups also means you may have to rewire the mics into a stereo plug - unless you have left and right mic sockets - onto a stereo jack plug as the standard telephone pickup plug is mono (it should record the same mono signal on both channels though due to the way the plug is made - if not a cheap mono to stereo adapter is handy). One plus regarding having an ear plug in to monitor is that CMs think you are listening to your mp3 player 
Generally you get what you pay for.
That PCM-M10 looks really good with nice simple front controls but out of my budget alas. 
May just put that on my next Christmas list!
I'm still very much a novice myself but the results have certainly been pleasing and far better than recording live. The Zoom H2 can be a little fiddly to use (the one I have needs the record button pressing twice and I keep forgetting) 

[772pilot]

Eyore mentioned something pretty important too. ALWAYS monitor your recordings as you make them (AKA listening with earplugs). That way you'll be able to determine the best pickup placement an addition to being able to hear if your recording is botched before you get home.

[eyore]

Silly as it sounds, some people (ahem, cough cough) forget that some recorders don't have a loudspeaker for playback so you need earphones to hear them although, in recent years, I  now take a decent iPod speaker (and a wire) with a line-in to play things back at the hotel in decent quality. What sounds great on the earplugs can sound a little different when played through a proper speaker (quiet recordings sound fine until then). As I said, still pretty well a novice so learning the hard way. I can always go back into the park and re-do them if I'm still there rather than at home 

[Mara]

I'm back with some questions about headphones this time.

I'm thinking about trying to do some recordings using the ALD system. Does the quality of the headphones make a major difference in the quality of the recordings? If so, can someone make a recommendation or provide information on what specs, type, or brand I should be looking for?

Thanks.

[pixelated]

I'm back with some questions about headphones this time.

I'm thinking about trying to do some recordings using the ALD system. Does the quality of the headphones make a major difference in the quality of the recordings? If so, can someone make a recommendation or provide information on what specs, type, or brand I should be looking for?

Strictly speaking, headphone quality does not matter at all, because the headphones are not part of the chain of input devices between the speaker and the end result of a digital audio file.  I.e., the recording quality is the same with good or bad headphones since they are only monitoring the recording.

But... the practical difference is that better headphones will let you hear the signal with better clarity and that in turn will let you get the best setup for your recording.  I.e., you can better optimize induction pickup location, decide which hum/whine/buzz you'd rather have in your recording, etc.  Usual bootlegger stuff .

[eyore]

and do remember my earlier remarks. Things can sound quite good over headphones and turn out to be a poor recording (due to differences in volume etc between the recording and monitoring levels). As pixelated says, they help get the location, pick up unwanted sounds and such but you still need to make a comparison between what you hear and what the recording sounds like. I spent an hour recording a loop which sounded great through the phones but was very, very quiet when I played it at home  You need to learn how a good recording sounds so maybe better to stick to the same type of phones be they good or bad (mine are the cheapest I can get - naturally). Experience will teach you. Better to stick to the in-ear type (mine are over-ear that fit over my ears as I can't keep the buds in!!!!  as big phones will get you noticed. If your home audio sounds decent and clear on them, they should be fine.