CineForm HDMI Recorder Concept Posted

[Fredrik-Larsson]

Having a Canon XH-A1 I would have to wait for the component in version but here are my thoughts.

I would like to be able to have four tracks of audio. I am not a pro on this but I guess that for they who have HDMI they get 2 audio tracks from the HDMI signal and 2 for the additional audio inputs. When using component in there is only video and hence I would only get 2 tracks of audio (using up the analogue inputs). Having four analogue inputs with the components in makes it much more interesting for me.

Make the AD-converters 24 bit and 96 khz sampling if possible. Of course make sure the AD-converters is of good quality and with excellent S/N-ratio.

Balanced audio would be very, very nice but I would accept RCA if I had to. As an alternative to XLR you can use balanced 1/4" phonejackets (very common in the music industry). I would prefer them instead of mini-XLRs. However an additionally option to keep a low profile of the device is to use a breakout cabling bunde similar to what M-Audio has on their Delta 1010LT
http://www.m-audio.com/products/en_u...10LT-main.html

In the same way you provide output power for an alternative HD-SDI to HDMI converter it would be nice to get the power to drive one (or two if I get my 4 channel audio) of these babies:
http://www.m-audio.com/products/en_us/DMP3-focus.html

It would be interesting if it can generate and receive timecode. I would imagine a scenario of having 2-3 cameras and 2-3 of these recordes syncing up with each other. It would generate more sales and what a neat flow it would be in post to not have to sync up all of the files. Midi devices (music instruments) have had MTC (Midi Time Code) since the 80s and I can't imagine it too be very expensive to add. It can even be propriety Cineform time code so that your devices talk with each other but then perhaps a pro version where it can generate external timecode for they who need it. Maybe firewire does this already with some cool gadget but I haven't heard of any though...

It might be obvious but running by both chord and battery would be nice especially if they are used in a studio scenario with multiple devices.

Make it possible to set naming convention of the files. A Fostex portable recorder has a nice way of doing it. I can set prefix e.g. x_03a_nnn where nnn is the take counter that adds one for each press on record. Of course I can reset that counter to 1. I think the Cineform HDLink does something similar when capturing from tape but if it's in this device I would actually rename the scene and angle.

I guess that's all I can think of now concerning the specs. Would I buy it for 2k if it had my additional specs? Mmm... most likely. I currently don't make a living on moviemaking so it's stretching it a bit. But I can't see why a pro or a semi pro wouldn't buy it. It saves precious capturing time and in a multi recording scenario it would be gold. The greatest benefit I see would be in combination with the audio since you save time in post and can get a feed different sources such as a mixer in a live concert situation.

[Jocelyn Deguise]

So far, I would buy the device as it is described on the Cineform website.

Sure, dual XLR inputs would make it just a bit more perfect, but as it is, my sound mixer can output 2 tracks rca audio as well as XLR. I could live with that !

Let's hope I can buy one soon !

[Matt Moses]

Awhile back on this thread I mentioned a $999.00 price point to be a "magic" price for me. The more I thought about it, the more I realized that this device will NEVER be a standard accessory to an HDMI consumer camcorder. The general public can't even discern HDTV from SD broadcasts!

Getting this done for $2000.00 makes a $999.00 HDV camera not that much different (image quality due to lossless compression, not lens characteristics) from any of the $6000.00 pro-sumer cams... so $2k is a pretty good deal... Even turning a new SONY HVR-Z7U into a decent Pro rig.

** I would definitely BUY THIS CINEFORM RECORDER before I buy a new camera!


:)

[Alex Raskin]

Interestingly, of all people who commented on audio input options for this recorder, almost no-one (including me) mentioned the Quality of AD converter.

Quality is hugely important, so:

> 24-bit 48Khz processing
> 105dB+ dynamic range
> better than -100dB THD + noise
> Flat frequency response 40-16,000 (+/- 0.1dB)

is what we need.

All this is needed to preserve the quality of the double-system audio to be fed in from the pro mic preamp/mixer at the time of recording.

Am I asking too much?

For the reference: $120 Emu 0202 standalone AD/DA box does even better than aforementioned specs, so it's very doable and should be planned.

I hope :)

[Fredrik-Larsson]

Originally Posted by Alex Raskin

Interestingly, of all people who commented on audio input options for this recorder, almost no-one (including me) mentioned the Quality of AD converter.

I totally agree that the quality of the AD converters are important. With 4 channel audio it can be that little thing that tilts us to buy this instead of something else. And like you mentioned I can only guess that there is a lot of fairly priced high quality AD converters on the component market that makes sense to add to this kind of product.

I am eagerly awaiting what the people at Cineform will say and.. when... :)

[Craig Irving]

I guess I'm still a little confused over the need for XLR connections, or even the analog connections for that matter. What application would you use these for?

I suppose it'd be great if it would allow more inputs than what the camcorder offers for recording, or better quality A/D conversion. But aren't we still using the camcorder to plug the mics into? Isn't that A/D conversion still happening at the camera end with its pre-amps and sending it out through the HDMI? Aren't we still recording the same audio to the HCR-1 that the camcorder would record to tape?

I suppose it *would* be great if the HCR-1 could improve on its pre-amps and offer something better audio-wise than what the camcorder provides, but I didn't think that was the intended purpose of the recorder. And if we were sending mics directly to the HCR-1 w/ XLR or 1/4-inch or whatever, wouldn't that mean we would need to battery-power our mics, or go through a mixer that supplies phantom power? I think I'm missing something here...

I too am eager to hear what the latest development has been at Cineform on this product. Hopefully they can tease us with a few more details to hold us over until NAB.

[Alex Raskin]

Originally Posted by Craig Irving

aren't we still using the camcorder to plug the mics into?

Yes, and on-cam mic preamps are subpar by manufacturers' design.

The video community consensus seems to be that on-cam audio is artificially kept low quality by the manufacturers of the prosumer cameras to protect their pro model lines. Remember, quality of audio makes more significant impact on the movie viewer than quality of visuals. So camera makers don't want us to get the same audio for less than $10K that they equip their $80K cams with.

On the other hand, quality audio is actually, truly difficult to achieve, and only a few reasonably priced mic preamps are available that feature good specs.

So the name of the game right now is to get a sub-$10K cam that has pretty good video quality, and pair it with the quality external mic preamp, and then multiplex these video and audio streams into one synchronized video file.

That's why Cineform Recorder box must have quality audio bus, on top of video.

[Fredrik-Larsson]

Originally Posted by Alex Raskin

That's why Cineform Recorder box must have quality audio bus, on top of video.

He he.. you beat me to it. :)

Additionally I would like to add that the more audio inputs you have the more mics you can use e.g. wireless, boomoperator, ambience, feed from mixers et.c.

The obvious benefit of what Alex mentioned is that you save a lot of time in post production since you don't need to sync video+sound manually.

[Craig Irving]

Yeah all those advantages sound great.

But if we suppose that Cineform will stick with the analog audio connections, if I don't use them, can I still count on it to record the audio in sync with what's coming from the microphones I've attached to the camera. While still being identical in audio quality with what I would be recording to the tape?

I guess I just want to make sure that there wouldn't be any drawback.

[Fredrik-Larsson]

Originally Posted by Craig Irving

Yeah all those advantages sound great.

But if we suppose that Cineform will stick with the analog audio connections, if I don't use them, can I still count on it to record the audio in sync with what's coming from the microphones I've attached to the camera. While still being identical in audio quality with what I would be recording to the tape?

I guess I just want to make sure that there wouldn't be any drawback.

If you are using HDMI it will be the same quality (already digital). Don't know if it will be post sound compression in this case or not.

If you have component i.e. no audio transmitted you will probably loose some quality since it will go like this: mic --> camera --> recorder
There will be a quality loss but it might not be audiable.

[Denis Danatzko]

but, while I've learned a lot from this thread alone, the more I learn, the more I realize how little I still know. It seems the "benefit" of every little tidbit I learn results in more questions in an inverse degree of magnitude to my newly learned info. (In simple terms, I'm uncertain that I "know" anything at all)!

Originally Posted by Fredrik-Larsson

If you have component i.e. no audio transmitted you will probably loose some quality since it will go like this: mic --> camera --> recorder
There will be a quality loss but it might not be audiable.

I've never worked w/component. But, for the lack of audio,
what would be lost/sacrificed if the chain were
mic -> mixer -> recorder?

TC maybe?

(Any replies will be my lesson for today).

Thanks.

[Fredrik-Larsson]

Originally Posted by Denis Danatzko

But, for the lack of audio,
what would be lost/sacrificed if the chain were
mic -> mixer -> recorder?

TC maybe?

Well, that would be a nice flow but you would probably use a dedicate mic pre-amp with better quality. A mixer has the option of sending the signal all different routes to sound effects, inserts et.c. so it will probably have a longer signal chain than a clean pre-amp. Though it might be a field-mixer which is I guess somewhere in between a pre-amp and a fullblown mixer...

The best flow would be:
mic -> pre-amp -> recorder

since inside your camera you will probably have poorer mic pre-amps and it might even be encoded to digital signal on the input and then decoded to analog on the output (maybe not since the video signal is uncompressed on the output).

[Jason Rodriguez]

BTW, you have to watch-out with the specs on those small, cheap "24/48" recorders . . . often times the specs they list as far as dynamic range, etc. are based more off the combination of parts in laboratory and spec-sheets vs. the "real-world" scenario . . . not that they're not "good", but just that a lot of times when they list 105dbA, etc., it could be more along the lines of the theoretical dynamic range of the chip inside that is doing the A/D conversion rather than the actual measured response from the recorder. This is not disengenuous, I mean the A/D converter, and even the electronics themselves might have that theoretical limit, but that may not be what you really get once everything is combined into one package and you're recording in the "real-world".

Also sometimes total dynamic range is measured by the absence of signal, and then the maximum signal, vs. what the possible "captureable" dynamic range is (i.e., what the electronics can capture in dynamic range all at once) . . . for instance some LCD manufacturers get their higher dynamic range numbers not by making a darker display with better black levels, but by making a brighter one and then measuring from when the monitor has been dimmed all the way down to the brightest the monitor can deliver . . . but the "true" full-swing dynamic range when the monitor is on is less than the advertised numbers since the backlight washes out the black-levels (i.e., black against white on the same screen at the same time).

Another thing to consider is that you can get a very high-dynamic range A/D converter, but if you do not properly isolate those electronics, and there is something noisy near-by on the PCB, you're going to lose the benefit of the higher-dynamic range gain that 24-bits gets you over 16-bits . . . in other worlds it does not take much noise (and for most intents and purposes, it would be hardly noticeable) to eat up those lower bits with an A/D converter that has a linear response, making the gain in bit-depth simply a gain in the ability to digitize noise.

[Herve Nisic]

Originally Posted by Carl Middleton

I would have to agree with the comments about non-HDMI cameras like the Z1.

Carl

Just to mention that my Z1 does have a HDMI plug !

all the best

Hervé

[Robert Kennedy]

Please offer AES audio inputs. That is the only way to preserve the quality of audio collected by audio professionals.