Film-Tech Forum ARCHIVE: Flashing light on DMA8plus.

This is topic Flashing light on DMA8plus. in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Stephen Furley (Member # 1277) on 03-06-2014, 11:04 AM:

I was setting up a Blu-Ray player on Tuesday evening. Original player disappeared long ago, so they bought a new one. They bought one with only three connections, mains in, HDMI out and Ethernet. No audio output to connect to anything, and the usual HDCP problem. Got hold of a HDMI to analogue, either Y,Pb,Pr or RGBHV, adapter, which also de-embeds the audio and outputs it as either analogue or optical S/PDIF. Converted that to co-axial and fed it into Digital 3 on the DMA since the optical input is already in use for something else. Works fine, picture and sound are very good, but the 'valid clock' indicator on Digital 3 is flashing, at about 1 Hz. never seen this before, and can't find anything about it in the manual. everything is still working fine. Any ideas.

Posted by Manny Knowles (Member # 1171) on 03-06-2014, 05:58 PM:

It may be struggling with the clocking, but not giving up.

Is that a "real" bluray or a "burned" one?

Also, have you tried rebooting your DMA8plus? Mine needs frequent rebooting. It's ridiculous.

Posted by Marco Giustini (Member # 4544) on 03-06-2014, 06:11 PM:

The DMA8+, as any Dolby product, can only support Dolby Digital. Maybe you were playing DTS?

I would strongly advise for a quality BD player. If you have a DMS8+, one with analogue outputs, which can decode DTS-only BDs for you.

Posted by Manny Knowles (Member # 1171) on 03-06-2014, 09:14 PM:

quote: Stephen Furley
Works fine, picture and sound are very good...

If the sound was DTS he'd get no sound at all.

Posted by Marco Giustini (Member # 4544) on 03-07-2014, 01:41 AM:

I missed that sorry.

Posted by Carsten Kurz (Member # 5396) on 03-07-2014, 03:15 AM:

That setup with the HDMI->analog converter and audio passthrough is a bit exotic, which is probably the reason you get this issue. What projector do you use? As BluRay Players are usually cheap, you could have taken an easier route by taking e.g. a Sony with HDMI + S/P-DIF. Usually, cheaper BluRay Players have koaxial S/P-DIF outputs anyway. The Sonys, even the cheapest, have the benefit that you can disable their OSD completely plus they stay in pause unlimited.

- Carsten

Posted by Steve Guttag (Member # 268) on 03-07-2014, 06:49 AM:

Now that Oppo can also disable the OSD (and screen saver)...I'm solidly on them now. They have ever output one could need (analog or digital), play/decode most everything and have dual HDMI outputs so you can have a preview monitor. And, quite frankly, the images out of them sure seem to look better too.

Posted by Scott Norwood (Member # 30) on 03-07-2014, 07:42 AM:

Regarding the Oppo (getting way off topic, I know): in at least some cases, using the second HDMI output for a preview monitor can cause the on-screen image to flicker when the input on the monitor is changed during a screening, even though the projector and monitor are using different HDMI outputs.

This is annoying, but, otherwise, yes, the Oppo is the best (least-bad) BR player right now. Unfortunately, the current model has no analog video outputs at all (not even composite).

Posted by Stephen Furley (Member # 1277) on 03-07-2014, 10:14 AM:

Not a recorded disc, it does it with a real disc, playing content from a memoory stick in a USB port on the player, or not playing anything at all, as soon as the player is turned on.

The DMA is had just been powered up, The cinema is not yet in use. First screening will be 20th March, then 27th and 28th, then two screenings each Thursday from the following week. I will be running the first few shows. I used to have to re-boot the DMA from time to time when I worked there before the cinema closed, but I upgraded the firmware and it seems to be more stable now, during quite a bit of testing which we have done.

The weak clock sounds possible. The flash seems to be quite regular, it looks like something which the DMA is intending to do with the LED. I wonder if cleaning the Toslink cable, or replacing it with a better one, would help. It's only one metre long. I don't know the history of the one that is there now; I found it with a pile of other cables. I think I might buy a better one tomorrow to try. I've used the optical to co-ax converter frequently in various places, and never had any problems with it.

The player is a cheap Panasonic, but the quality is as good as anything I have seen from more expensive ones. It can play video files from USB devices, or from Windows servers over Ethernet. It had various annoying features, but almost everything can be turned off. It even put out button clicks from the remote control on the embedded audio in the HDMI for some unimaginable reason.

Choice of player was not mine. Original one went missing after the cinema closed, almost three years ago. The cinema is not ours, it belongs to the council who will be renting it to us for a few hours each week. The rest of the time it will be used for other purposes; there was a poetry reading going on there one evening recently for example. most screenings will be digital cinema with occesional special events on film, DVD, Blu Ray etc. The first screening will be on Blu-Ray, which is why I'm keen to make sure that it's working reliably. That was the player they chose to buy. Having said that, I'm impressed by both picture and sound quality with it connected the way I have it now. I don't think there are any new players available now which have analogue outputs. It would have been nice if they'd bought one with an audio output, but they didn't.

I have configured the player to output Dolby Digital and PCM as bitstream, and DTS decoded to 2-channel PCM, with matrix encoding. The DMA is configured with matrix deconing for two channel material 'on' for PCM and 'auto' for Dolby Digital. That is the best I can do with the available equipment. It still sounds pretty good. Most of the more recent discs do seem to be using DTS DTS-HD master, so the player has to do the decoding.

I have to say that I'm impressed with Blu-Ray. Considering that it's a cheap, highly-compressed domestic format it can look very good. It's a pity that they didn't retain Dolby Digital on all discs for people with older equipment.

Posted by Chris Slycord (Member # 4239) on 03-08-2014, 06:15 AM:

quote: Stephen Furley
It's a pity that they didn't retain Dolby Digital on all discs for people with older equipment.

I'm sure the other blu-ray rippers have this as well, but DVDFab allows you to rip the content and convert any of the HD soundtracks to AC3 if you wish. And then you can use the content to burn onto a blank disc that'll have the same picture as before but will work fine on your older DD-only equipment.

Posted by Stephen Furley (Member # 1277) on 03-11-2014, 06:06 AM:

True, that would be possible, but when a film is being run only once, and you get the disc not long before the screning, it's not really something that I'd want to do.

The problem was the Toslink cable by the way; after cleaning both optical ports and replacing the cable with a better one the flashing has stopped. Although it was working ok with the old cable I was a bit worried because there is an important special screening coming up soon which will be from Blu-Ray. All normal screenings will be from proper DC.

Posted by Antti Nayha (Member # 4980) on 03-11-2014, 08:08 AM:

quote: Chris Slycord
DVDFab allows you to rip the content and convert any of the HD soundtracks to AC3 if you wish. And then you can use the content to burn onto a blank disc that'll have the same picture as before but will work fine on your older DD-only equipment.

There are also Blu-Ray players that can do that on the fly. At least Samsung BD-D8200N/D8500N (and probably some other Samsungs) has an option for re-encoding everything to Dolby Digital AC3. Works like a charm with DMA8Plus.

Posted by Stephen Furley (Member # 1277) on 03-11-2014, 09:05 AM:

That's interesting; it's unnown how much Blu-Ray will be used at the moment, but if it becomes at all frequent then it might be worth trying to get a new player.