A new front-end for Hi-MD recorders?

[ozpeter]

http://www.ikey-audio.com/ikey.htm looks VERY interesting - think about it - could this be used to record on location to an MD recorder using it as a mass storage device, thus bypassing all the Sony drm etc stuff??

[dex Otaku]

I doubt that HiMD would actually be able to keep up to continuous recording in mass-storage mode. It would be nice to be proved wrong though. I wonder what the audio specs are like for it.

[ozpeter]

As memory serves me, I did manage four tracks of Audition audio onto a Hi-MD - must repeat the experiment.

Looking at the features, it's a pretty basic device, and in combination with Hi-MD it wouldn't be of any use in stealth situations, but combined with a small mixer (which could provide better control of level and provide monitoring etc etc - not to mention a mic input) it could make a pretty neat portable outfit.

I don't doubt others like it may appear, perhaps with more facilitities.

Spec from the site:-

Sampling Rate: 44.1kHz, 16 Bit

Dynamic Range: 98 dB

THD+N: -91 dB

Freq Response: 20Hz – 20kHz

Edited December 1, 2005 by ozpeter

[ozpeter]

Transferring a c.3' stereo wave file direct onto the Hi-MD from the PC takes about 1', so logically it seems to be capable of recording at a bandwith of 3 x CD spec audio.

[guyj1]

Bypassing DRM would be the only thing I could see as a use for this device. But since you can pass Analogue Hi-MD recordings from MD to PC already why bother? Besides the Ikey only has an RCA line in connector so that would mean you can only make soundboard recordings with a patch cable, right?

I would be more interested in this device if it had Mic connectors and I owned an Ipod.

[dex Otaku]

Peak read speeds are roughly twice what peak write speeds are. It is definitely enough for 1.4Mbps writing, but the difference between it writing PCM as audio and it writing as a mass storage device is that the audio way buffers things a ways before writing; mass-storage mode I would doubt could sustain 1.4Mbps write speeds; if the disk were even remotely fragmented, or had to seek for any reason, you would likely get dropouts due to buffer overflows.

That's theory, mind you. The only way to find out is to try it.

[Sparky191]

Theres no DRM issues with analog stuff on a HiMD is there?

[rei-gouki]

Not since SS 3.3 came out.

As to the write, though it buffers, it does have to write the 1.4Mbps data at least as fast as real time as for a sustained long term recording, the buffer is just there for the convenience of the writing head so it doesn't drop out if it has to look for spots to write the data. If the write is too slow, you will eventually run out of buffer. I have a good feeling that the write speed is reasonably faster than real time to accomodate this.

As to actual sustained writes, I would imagine that there may be a heat problem with the disc rubbing on the MD caddy for prolonged periods instead of short runs and long walks as system tries to buffer data to listen to.

[ksandbergfl]

Peak read speeds are roughly twice what peak write speeds are. It is definitely enough for 1.4Mbps writing, but the difference between it writing PCM as audio and it writing as a mass storage device is that the audio way

That's theory, mind you. The only way to find out is to try it.

Actually, this device could be thought of as a "digital audio input" for the HiMD.

the Ikey site says it records in MP3 format too, max rate 256Kbps. I think the HiMD could handle that, for sure. 1.4Mbps WAV might be a stretch, tho.

HiMD can copy ~1GB data to a disc in about 30 minutes.... ~33MB/min. 256Kbps is only 2MB/minute.... 1.4Mbps is about 10MB/min.

[dex Otaku]

Actual read speeds are here: [write speeds are roughly half]

http://www.minidisc.org/hi-md_faq.html#r_q104

Note that copying PCM from HiMD runs much slower than the stated 9Mbps peak read rate.

What I'm theorising about is the fact that writingin audio mode [whether from an analogue source or from optical SP/DIF] is likely done differently than writing in mass-storage mode. Audio modes are specifically for audio, where the write-speed of a given bitrate is known beforehand, and the length of the recording buffer is a fixed amount of time.

Neither can be known in mass-storage mode, since it's just data being sent to the unit. There's no knowing - without testing - whether mass-storage mode is buffered in any way similar to audio mode. Also, the external A/D + USB controller unit we're talking about here might do buffering of its own [highly likely, I'd say] which could overcome this problem in any case.

[ozpeter]

I've read in some posts on another forum I frequent ("AudioMasters") that a couple of members there have this device on order, so end-user test results may become available soon. One may be by a highly respected audio engineer who may try it with an NH600.

Another factor in all of this is the impossibility of turning off track marking, and the funny things that happen at track marks. So audio written as data to the drive might have some advantage there.

[ozpeter]

The guys at AudioMasters now have their units and - yes, you can record onto Hi-MD just using this device to input straight into the usb socket. So if you want an alternative means of wave recording on your Hi-MD machine, just using it as a mass storage device - or mp3 - this is perhaps the first way to do it without a PC. Goodbye SonicStage, if you don't mind the added expense and eqipment.

There are however some question marks over the unit - read for yourself if interested at http://www.audiomastersforum.org/amforum/v...p?p=44722#44722 - especially the later posts written after their iKEY-Audio devices had arrived.

Edited December 3, 2005 by ozpeter

[ksandbergfl]

I doubt that HiMD would actually be able to keep up to continuous recording in mass-storage mode. It would be nice to be proved wrong though. I wonder what the audio specs are like for it.

This is an old topic, I know. But I finally got around to doing a test.

HiMD "records" MP3's in mass-storage mode just fine. It has no trouble keeping up. As a matter of fact, it can "record" to a WAV file (uncompressed 44.1KHz PCM, 10MB/min) just fine too, although you can hear the HiMD disc spinning up a lot more often.

For my test:

I used a 2.2GHz PC with Windows XP. I have a Sony MZ-NH-600D with a 1GB disc.

I connected to Launchcast, selected a channel.

To record, I used AudioGrabber (http://www.audiograbber.com-us.net). I setup AudioGrabber to save the "Wave Mix" directly to MP3 using the LAME MP3 encoder. My MP3 settings were 192Kbps "high quality". My output directory for MP3's was my E: drive (the HiMD). A 4-minute song took up roughly 6MB. The HiMD had no trouble keeping up with the incoming data. I recorded 5 songs in a row, all with no problems.

Test 2 was the same, except I set AudioGrabber to record to WAV instead. A 4-minute song took roughly 40MB. I recorded 4 songs in a row before stopping, all were fine.

Summary: HiMD would work OK as a "mass storage" device for recording output from a device like the device from AudioMasters in this topic.