Professional-Grade Audio Recording With A PDA

matt-fu writes "For a long time, live recording has been consigned mostly to the realm of DAT recorders, Minidisc recorders, or laptop computers. On one hand you have subpar sound quality, on the other you have a bulky rig with a big 'steal me' sign attached. Thanks to the folks at Core Sound though, mobile recording is about to take a huge leap forward with their PDAudio project. By using a hardware card that allows recording via S/PDIF onto Compact Flash, you will be able to use your iPaq or Zaurus alongside a decent A/D converter to portably get field recordings at up to 24bit/192kHz. The site includes WinCE screenshots, and there are Linux clients in the works as well."

Comments

I Can see it now

[dirkdidit]

Miss Cleo: I'm seeing high quality concert bootlegs in the future, along with a good chance of RIAA lawsuits. Be prepared as the death card is also in your future.

Re:I Can see it now

[Read Icculus]

There are plenty of uses for this besides piracy. Such as legal taping of concerts, like on http://etree.org/. Hopefully the linux version comes around soon as I'm looking foward to trying this out.

Re:I Can see it now

[Saeger]

There are plenty of uses for this besides piracy.

Didn't you get the memo?

"Innocent until proven guilty" is OUT, and "assumption of guilt" is IN, along with his friend: "preemptive defense."

--

Thanks a lot.

[Anonymous Coward]

Now we can expect a special music piracy tax on PDA's as well.

Size Limitations

[shepmaster]

So, who would be interested in nothing more than a high-quality sound bite? Most CF and similar products are small, and audio recording is big. Or are there multi-gigabyte flash cards in the making?

Re:Size Limitations

[jandrese]

I wonder if they're going to include some form of lossless compression (like flac) on the sound to squeeze more bits out of the 4GB CF card mentioned in the article. As it stand, you can only get about an hour of uncompressed 2 channel 192 Kilosample 24 bit audio on there. With compression it should be easy to get 2 hours out of the card. If you use a lossy compression (like ogg) it should be trivial to get many many hours on a 4GB CF card.

Re:Size Limitations

[mattkime]

you'd only use one channel anyway. how could one person record two channels of audio at a concert in the crowd? they'd both sound the same

Re:Size Limitations

[soupdevil]

How far apart are your ears?

Can you hear two channels of audio at once?

Re:Size Limitations

[hackstraw]

Actually, some mikes that are used in audience concert recordings have different cartridges to change the reception pattern of the mike (cardiod, hypercardiod, shotgun, etc ). Why? For better stereo seperation at different distances from the stage.

A good stereo audience recording sounds excellent. They really have that "there" feeling. I've actually jumped listening to a recording when a balloon popped near the mikes!

Some people have meantioned using minidisc for shows. I have never had a recording come from a minidisc. I've seen "tapers" use minidiscs, but there not considered tradable, they are for personal use only.

Regarding the recording of music on PDAs in general, I don't see this happening. There isn't a need. A minidisc is about as small as your gonna get, if size is what your after. Also, many of the current tapers have a dat deck, a good A/D converter, and some even have separate preamps to give gain from the mics to the a/d converter.

Trust me there are plennty of excellent recordings out there for many taper friendly bands. Many of the recordings have detailed lineage of the source. For example:

FOB B&K 4006 omni's (in hat, 36th row left of center) > Lunatec 316> Panasonic SV-250 by Marc Nutter; Transfer: Sony DTC-A6 > Dio 2448 > SF 4.5 @ 48K, Resample, add fades> CDWAV> SHN

This is from a recording 8 years ago, taping is almost godlike now!

Re:Size Limitations

[dougmc]

192khz sampling and compression do not fit together.

As long as you restrict yourself to lossy compression schemes, you may be correct (it's still a controversial subject, of course.) However, you may not have noticed this, but the person you responded to mentioned *both* lossy and lossless compression.

(Of course, he did incorrectly suggest that lossless compression requires having the entire stream at once, which is patently incorrect. Obviously he's never heard of gzip or bzip2 -- both of which are lossless and compress streams block by block -- but aren't that great at compressing audio streams. There's more on various lossless audio-specific compression programs here.)

Note that even lossy compression is not always bad. mp3s and Oggs at 128Kbit/s may not be CD quality, but they're pretty good -- and yet it's compressed by a 12:1 factor! Increasing the bit rates will reduce your compression factor, but will increase the quality.

Jpeg files are lossy, yet with higher quality factors the quality is so high that you can't even tell the difference with your own eyes.

An audiophile may not be at all happy with 128Kbit/s mp3 files, but as you increase the bit rate, there's likely to be a place where he can't tell the difference between the lossy compression and the original. (Of course, depending on how strongly he hates lossy compression schemes, he may never actually admit it.)

At that point, what matters is the compression ratio compared to what you could get with a lossless compresser.

You wouldn't want to use a lossy compression scheme for compressing the studio masters (you should always do your mixing and such with no compression or lossless compression), but if the quality is good enough, it may be perfectly ok for the final distribution of the music, even for the audiophiles. 128 Kbit/s mp3s don't cut it, but that doesn't mean that `mp3 sucks!'.

Provessional-Grade Video Recording With A PDA

[Spyffe]

This is really cool, but there are good solutions (MiniDisc, etc.) already for audio recording. This may have advantages over them, but there is still a significant installed base out there which will make adoption slow.

Perhaps a video version of this could be developed, holding DV video? One of the difficulties of Mini-DV, just as DAT, is its linearity, which makes editing a chore. Combined with the LCD display on the PDA, a DV version of this tech could enable basic editing on the fly. It could do for video what MiniDisc did for audio.

Re:Provessional-Grade Video Recording With A PDA

[ericdano]

I do a lot of field audio recording on a minidisc with a Rode NT4 Stereo mic. The biggest problem is that you have to play the recordings back. You can't just transfer them off the discs like a file. That is a pain, and this device might solve that problem.

The other problem is that using the internal mic battery versus the phantom power there is a difference. Phantom power makes the mic sound better. And if you can record at 96Khz, thats even better. Better sound quality, etc, etc.

I'm a little skeptical about this product. My minidisc is real durable, and it works, and it's a small rig to take places. The pictures on core's website looks like a lot of gear to carry around....

Re:Provessional-Grade Video Recording With A PDA

[worst_name_ever]

This is really cool, but there are good solutions (MiniDisc, etc.) already for audio recording.

No no no, this is completely different! It replaces the fragile, expensive MiniDisc recorder with a... PDA... oh wait...

Re:Provessional-Grade Video Recording With A PDA

[van der Rohe]

Minidisk uses ATRAC compression, however, so it's not the same quality as DAT for example, which can record at CD quality (16 bit, 44.1 kHz.)

This PDA solution appears to provide high-quality sampling rates/bit depth without relying on compression.

Good!

[TerryAtWork]

How many great concerts have disappeared into the ether because no one recorded them?

A LOT!

And artists - if you are concerned that pir8's will swipe all your material remember that piracy makes the pie bigger and the bigger the pie the bigger your slice, and that the Grateful dead encouraged this sort of thing and they had the second most lucrative tour after U2 and that the pir8s are in fact working for you for free - all you have to do is grab their best stuff and publish it yourself ala Zappa in Beat the Boots.

Re:Good!

[Sycraft-fu]

If record companies were smarter, they'd record all the concerts themselves. I mean, you already have a full audio setup for sound reenforcement. With just a little extra effort it could be setup to do a good job recording, or for 0 extra effort a DAT can by plugged into the main output and that captured.

Then, sell it all on your website. Let fans buy, either through download or purchasing custom burned CDs, all the songs from concerts they want. If they feel like getting a particular performance of a particular song, they can and you make money on it.

Of course this is all WAY too high tech and progressive for the record companies so it won't happen.

Re:Good!

[Mononoke]

If record companies were smarter, they'd record all the concerts themselves. I mean, you already have a full audio setup for sound reenforcement. With just a little extra effort it could be setup to do a good job recording, or for 0 extra effort a DAT can by plugged into the main output and that captured.

Already being done by most bands, but only as a reference tape used to judge the quality of their performance.

Have you ever heard a 'board tape', as these are called? The mix is usually terrible because the show is being mixed to sound good for the paying audience, not the tape. Mixing a live concert and mixing to tape are two very different things. Real 'live-recordings' are recorded on separate consoles located away from the arena, at great added expense.

(Why are board tape mixes bad? Mixing a live show involves combining the sound coming out of the PA with the sound coming off stage (Huge guitar stacks and expensive snare drums are the worst offender in this regard.) The board tape is only getting half of what the audience heard.)

(Yes, I mix live audio for a living.)

Re:Good!

[Mononoke]

I think that the lure of boards for at least Grateful Dead concerts, was that the variability between shows was less from show to show vs. audience (microphone) recordings.

Dead board tapes also tended to be more like what the audience heard because of the size of the venues. On an outdoor show 98% of what the audience hears comes from the board, as opposed to 70% (or less) in smaller indoor venues.

Great

[Flunitrazepam]

With this, and cell phones the size of postage stamps that can stream live video, we are reaching a point where people are going to have to assume they are being recorded or filmed at all times.

Shouldn't that "bulky rig" ...

[DogIsMyCoprocessor]

have an "I'm bootlegging this concert" sign attached instead?

Hello? A to D converter?

[PhyrePhox]

This is not an all-in-one solution. You'll still need an encoder, and frankly, a portable DAT or MD recorder is: smaller; a single finished piece; designed specifically for this purpose; and (at least in the case of the MD recorder) much cheaper than a iPaq/A-D converter/this funky card.

What about an Archos

[toxcspdrmn]

I can do pretty much the same with my Archos Jukebox Recorder and an amplified microphone. With on-the fly VBR MP3 encoding direct to a 20GB hard disc, space is not an issue. And it fits in a pocket.

Re:What about an Archos

[delta407]

Do you honestly think that audio professionals store data in 160-kilobit VBR MP3s?

Besides which, can your Archos do 24-bit/192 KHz sampling? Professionally, very, very few people use 16-bit/44 KHz for anything serious.

Re:What about an Archos

[Mononoke]

Professionally, very, very few people use 16-bit/44 KHz for anything serious.

Just every single CD audio disk mastered in the world. Damn professionals.

(It's 44.1 KHz, BTW)

Re:What about an Archos

[delta407]

Right, of course, the final product is almost invariably 44.1 KHz, two channels, 16 bits per sample. But this is the difference: it's downsampled to that, after EQing and lots of other DSP. Except for some live stuff, very few professionals use such low quality initial recordings, choosing instead to have greater precision through the entire mastering process until it is discarded (actually, dithered and filtered away rather than truncated) at the end.

Then again, I have seen some audio equipment capable of higher sampling rates advertised at Best Buy recently. Of course, it was claiming that 96 KHz would make everything sound better and clearer and grander than before despite limitations of speakers, acoustics, and the listener's hearing... nonetheless, the future of audio is sounding better.

This could become something much bigger

[l0ungeb0y]

I have to say I'm impressed with what appears to be a very good product for handhelds.

I can't wait to start seeing micro-editing and remixing suites available as well, I'm sure it will only be a short time before we have the ability to DJ or Master Music on a handheld as we do on a laptop today.

Also, what about effects?
It shouldn't take much doing to convert that application into say a reverb or delay peddle. An all in one solution for applying Delay/Distortion/Flange/Phaser/Reverb/EQ would quickly find itself in virtually all performers eqpt bag in a heart beat.

Woo! 7 Minutes of audio on a 512M CF!

[Anonymous Coward]

24kbits*192KHz*2channels = 1.152 MB a SECOND. If you compress it, then whats the point of having such high fidelity anyways? Your 512M CF card is going to hold 7 minutes of audio data.

Why not just buy a portable minidisc recorder, which is smaller than a PDA, cheaper than a PDA, would probably have 10 times the battery life of this PDA-based monster, and has media that costs $2 a pop? Add to that the media lasts for a 74 minute recording at a quality that will definitely blow that PDA solution out of the water and you've got a complete waste of time.

I can't understand why most geeks would lambast the general public for falling for the Megahertz Myth, and yet they get all starry eyed when someone starts throwing preposterous specs out at them. Do you honestly think that you can get an appreciable difference between 16/44 and 24/192 outside of a professional studio?

This product is targeted at clueless audiophile wannabes. Unless you are one, move along.

Pro-Quality Audio? Sure...

[Dynedain]

You can have SPDIF, DAT, you name it....but if the mic sucks....so will the audio

Re:Pro-Quality Audio? Sure...

[theLOUDroom]

You might care to note that that company sells mics as well. (This device does not use the PDA's internal microphone).

This has been already done, but smaller is cool

[anarchivist]

Well, it all depends on what you consider professional grade. There are already digital four track recorders (the thing indie rockers usually know for their cassette eating tendencies) that use SmartMedia cards. Plus, on "high fidelity mode," the Zoom MRS-4 gets 17 track-minutes of 24 bit audio with a frequency response of up to 32 kHz on a 32 meg card.

Re:Woo! 7 Minutes of audio on a 512M CF!

[jokell82]

First, MDs suck for live audio recording. Why? Because it compresses the audio in a lossy method (just like mp3's). The MDs are the last in the line of quality, and this solution (although I don't think it will ever see the light of day, as it is Core Sound that's releasing it) would be much better than MD any day of the week.

And second, yes, you can tell the difference between 16/44.1 and 24/192. Try listening to a SACD or a DVD-A and tell me they don't sound better than a CD.

Re:Woo! 7 Minutes of audio on a 512M CF!

[DMaster0]

personally, I'd rather have a fully-digital device that can do 44.1/48 (which this can) and not have to deal with Minidisc, DAT's or anything at all that you have to transfer in real-time.

The potential is there though with this device, to work very well into the future as media gets cheaper and prices go down. 5 years ago, would you have assumed you could get a DVD-R for $2? 512MB of RAM for $50? 200gb of hard drive space for $150?

Of course not, with your thinking.

It's a shame so many people think that what exists now is the only thing that matters, and when someone shows you something that will likely be great a long time from now and is built with the expectation of advancement in technology, you say "bah, what is good now will always be good and who needs progress".

Re:Wrong

[Mononoke]

This is "professional" grade audio by the standards. S/PDIF is not *professional grade*. AES/ABU on a 110 ohm cable is. S/PDIF is considered "consumer" grade. No XLR cables, no pro... that's how it goes.

Not necessarily. They are only two different ways to carry the same digital signal. (AES/EBU is balanced signal, S/PDIF is unbalanced.) Yes, you want AES/EBU for longer cable runs to keep data loss to a minimum, but S/PDIF is perfectly suitable for short distances. Such as: From the Mic preamp in one jacket pocket to the PDA in the other. No need for balanced signal for that short a distance.

Yes, I Am An Audio Technician (IAAAT).

Re:Bullshit

[torpor]

Ummm... sorry to burst your pretty bubble, but 'professional grade' field recordings of concerts *can* be done with sub-$1000 microphones, well rigged to a portable system such as described here.

There's nothing that says "Pro = digital multitrack with multiple busses from the house mix".

Nah

[Sycraft-fu]

Even two normal mics with a cardiod pattern will produce some sensation of stereo if they are right next to eachother. However, they make mics specifically for this kind of thing. They have two capsules that face away form eachother and a pickup pattern such to give good stereo from one unit. The recording studio on the university has one like this, I don't remember what kind it is. Sounds just gorgeus for stereo drum kit recordsing. You just hang teh thing over the centre of the kit and it gets good stereo.

Re:Woo! 7 Minutes of audio on a 512M CF!

[ericdano]

Um, I don't agree with that. I use a minidisc all the time to record groups that I play with. It works great. What really decides on how good the recording is going to come out is the microphone and microphone placement. I invested in a Rode NT4 stereo mic about a year ago. That with my minidisc player/recorder has resulted in many high quality recordings. They sound at least as good as recordings made with a pair of house mics (Neumanns I believe) going to a mixing board. Actually, they usually sound better.

I don't think this solution, a PDA and an interface, is going to boost the quality any more. And it looks less portable.

What I'd really like to see is something like a recordable iPod.

Ummm...

[mindstrm]

So you use an s/pdif input card and record the data digitally on your pda... WHOPIE.

You still need, as it says, a DAC. Got a really small high quality dac? High quality mic? Got enough storage capacity for high quality recording on your pda?

A portable DAT recorder is still way better.

Woah there, hoss!

[bengoerz]

For a long time, live recording has been consigned mostly to the realm of DAT recorders, Minidisc recorders, or laptop computers. On one hand you have subpar sound quality, on the other you have a bulky rig with a big 'steal me' sign attached.

Subpar sound quality? The DATs that I've worked with have better resolution than CDs (48 KHz vs 44.1 KHz sampling), minidiscs are technically CD quality, and laptop computers can be equally sensitive given the right equipment. Given what I've heard of PDA sound, there's nothing subpar about the existing recording mediums. Also, it's hard to claim that a minidisc is "a bulky rig".

By using a hardware card that allows recording via S/PDIF onto Compact Flash, you will be able to use your iPaq or Zaurus alongside a decent A/D converter to portably get field recordings at up to 24bit/192kHz.

So to record in this way, I must buy a "decent" A/D converter and a bunch of Compact Flash. And, unless they are using some compression which will lower the sound quality, this thing will suck up more MB-per-minute of audio than a CD. Good thing Hitchai (formerly IBM) makes their MicroDrive, and I have a money tree in my yard.

So, bottom line as I see it? An interesting project, but one which uses expensive hardware and media that makes it prohibitively expensive. So if you want professional digital recording, get a professional digital recorder. If you want ad-hoc "pro" sound recording from a PDA, now you've got an option.

24 bits? right...

[svirre]

You are not going to get 24 bits recordings of anything battery operated.

The level of precision recuired to even begin to approach 24 bits recuire very high biascurrents in the device.

Actual 24 bit conversion is actually extremely hard. I am not aware of any standard device capable of this level of precision at audio frequencies, let alone 200KHz.

Also you will not find any mic or concert venue enabling you to deliver 144dB dynamic range into the adc. You will likely actually get somwhere between 30-60dB

Note: Do not confuse the wordlength with the precision. There are many AD and DA devices who output a lot more bits than they actually can deliver data for. This is done to justify the audio-biz need for specmanship. (stick a '24' bit dac in there so we can write it on the front panel, never mind the device is propably only capable on 16-18 bits)

Microphone basics.

[grumling]

Phantom power doesn't make anything sound better or worse. It provides +48vdc to a microphone to charge the condenser plates so that it will work. It can actually ruin some types (ribbon) mics.

Generally condenser mics (such as the Rode NT series), are higher quality and will produce superior recordings.

Nomad Jukebox3..

[rootlocus]

I am a musician who records a lot of live performances, and I just bought a Creative Nomad Jukebox 3.. I'm really happy with it.. For about $375 you get a 40 GB hard drive, and it can record to WAV or several different MP3 formats via the analog or optical line in..

I tried the Sony Minidisc recorder, but was disappointed by the built-in DRM (you can't copy your own recordings to a PC digitally, because it doesn't think you have rights to them)..

Battery Life?

[dimension6]

I think that before this can become a truly viable solution, PDA battery life must increase. Since this drains battery power (from what I understand), many PDAs will be unable to record an entire concert straight through. On a side note, I believe Sharp is going in the right direction with the Zaurus SL-5600's longer life battery.

Re:I'm confused

[dachshund]

Why would you need a balanced connection for a digital stream? Aren't errors handled with checksums and retransmissions?

Most digital audio interfaces are one-way, so no retransmissions. There is error correction, but it can only do so much in the face of heavy interference.

The CF card has windows and linux drivers...

[JoeMango]

...if you didn't notice. They won't be selling this stuff exclusively as a PDA kit.

The cool thing about this is not "Yay, you can record on your IPAQ!" but "Yay, someone is producing a digital audio interface in CF format with OpenSource drivers!"

I've thought that using the PDA to do my taping would be super-slick and would get me a lot of oohs and ahhs, but the PDA+4GB CF card+dual CF sleeve combo is WAY more expensive than a Nomad Jukebox 3, which I recently converted to from MiniDisc, and which I am ecstatically happy with.

Still, it's nice to see someone sticking their neck out and making a device that people want rather than need. Good luck Len!

Re:Woo! 7 Minutes of audio on a 512M CF!

[jafuser]

What I'd really like to see is something like a recordable iPod.

Now that would be something to get me to part with some cash in short order. Someone must have one in develompent by now?