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."

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: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: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.

Pro-Quality Audio? Sure...

[Dynedain]

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

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: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).

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: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.)

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.

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.

Nomad Jukebox3..

[rootlocus]

I am a musician who records a lot of live performances, and I just bought a Creative Nomad Jukebox 3 [nomadworld.com].. 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)..

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).