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#17918 - 10/05/11 07:54 AM Panasonic DVD Recorder Woes
grelber Offline


Registered: 08/05/09
Loc: North of 49th ||
Some time ago I acquired a Panasonic DMR-EZ48V DVD recorder with both ATSC and NTSC tuners. I connected it to my TV via the included 3-lead audio/video cable and later with component video and audio cables (5). My TV signals arrive over the air via antenna.

THE ISSUE
Digital signal - audio attenuation: The audio portion of digital signals (but not analog signals) is attenuated by ca 50% when the program is viewed via the recorder; if the same program is recorded on a DVD RAM disc, the sound level is diminished by another 50%. That is, watching a program on the TV (Panasonic Viera) with a sound level of 20 needs to have the audio boosted to 40 (to achieve the same audio level) when the same program is viewed via the DVD recorder and needs to be boosted to 70-80 when viewing the same program recorded on a DVD RAM disc.
(In other words the pass-through signal is normal but the direct signal is mishandled by the recorder.)

Anybody got a clue what's going on? I've tried 2 recorders and both have the same defect.

Panasonic's technical support and customer service seem to be staffed by less than competent people.

Back in August I spoke with one of Panasonic's technical services managers, who advised that there had been other complaints about the sound attenuation problem and that it had been brought to the attention of Panasonic engineers. He further advised that a firmware update to address the problem should be forthcoming in a matter of weeks.
Not only has no such update made an appearance, but other management personnel deny that any such thing is in the works. So, add to incompetence, lying to the customer.
Ain't it grand?!

Addendum
Nobody got nothin'?


Edited by grelber (10/06/11 05:20 AM)
Edit Reason: Addendum

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#18809 - 10/31/11 02:01 AM Re: Panasonic DVD Recorder Woes [Re: grelber]
grelber Offline


Registered: 08/05/09
Loc: North of 49th ||
Minor update — just in case anyone out there has additional thoughts and contributions to make on the subject.

Following 'technical' commentary is derived from discussions with one of CTV's chief engineers and with one of Shaw Media's (Global's) senior directors of engineering and broadcast systems.

With respect to the digital audio attenuation issue (apparently universal):

This is a puzzling problem which the above individuals have advised needs to be resolved/explained.

The baseline loudness setting ("dial norm") is the reference point from which the Dolby processor in the receiver aligns.

Shaw boosted the audio 6db to get them closer, but that "non-standard" setting caused all sorts of problems for BDUs.

The issue has been discussed with Dolby Labs who build the AC3 audio system used in DTV transmission. Their comment is there "shouldn't" be an imbalance if everything is correct but that there "often" is, specifically with the DTV audio being lower.

Dolby did explain that although in theory the audio level should not attenuate with digital compared to analog, it usually does. Dolby Labs did not implement this very well. Dial norm intentionally lowers the audio. This may not mean anything, but if you put in -20dbFS and set a dial norm of -24 (recommended in the ATSC standard), then decode that back to PCM audio, you will get -27dbFS audio, or 7db lower.

Since -3db represents half the energy, 7db down is actually quite a lot. In theory the TV and DVD recorder are "supposed" to compensate for this, but apparently that is where the "doesn't really work" part comes in.

Shaw Media have the same problem with their professional gear. If you feed "0vu" into a Dolby AC3 encoder, you only get -7vu out.

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#18812 - 10/31/11 08:57 AM Re: Panasonic DVD Recorder Woes [Re: grelber]
Bensheim Offline


Registered: 08/16/09
Loc: UK
For what it's worth, we got a Panasonic this year (to replace a dodgy Toshiba) and within hours of unpacking and installing and tuning it, it went back in the box and back to the supplier for a refund (which I was given in full).

Toshiba, the only other competitor in this market, fares much better in my experience. I had the Toshiba repaired (at their expense) and it is now back in service.

However, since I'm in the UK that might not help you at all.

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#18816 - 10/31/11 09:42 AM Re: Panasonic DVD Recorder Woes [Re: Bensheim]
alternaut Offline

Moderator

Registered: 08/04/09
Originally Posted By: Bensheim
For what it's worth, we got a Panasonic this year [...] and within hours of unpacking and installing and tuning it, it went back [...] to the supplier...

The critical thing here, of course, is why you returned the Panasonic. Was the problem identical to Grelber's or was it something else?
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#18820 - 10/31/11 10:01 AM Re: Panasonic DVD Recorder Woes [Re: alternaut]
Bensheim Offline


Registered: 08/16/09
Loc: UK
Nearly identical. I couldn't be bothered with trying to make it work as stated in the handbook*, so sent it back within hours. The packaging was still on the floor in the same room.

Having had previous experience with Panasonic "customer help" I had no intention of going down that trail again.

*I'm not stupid. I know how these things should work and I don't give up at the first attempt - or even the fifth, in this case.

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#18821 - 10/31/11 10:12 AM Re: Panasonic DVD Recorder Woes [Re: Bensheim]
alternaut Offline

Moderator

Registered: 08/04/09
Thanks for the update. It's interesting that you find that much of a difference between these brands. I wonder if it's systematic or just an odd coincidence.
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#18822 - 10/31/11 10:16 AM Re: Panasonic DVD Recorder Woes [Re: Bensheim]
grelber Offline


Registered: 08/05/09
Loc: North of 49th ||
The only 'problem' with Toshiba is that the only DVD recorder available in Canada is the DR-7, which unfortunately has only a digital (NTSC) tuner.

The Panasonic DMR-EZ48V has both NTSC and ATSC tuners (which is why I got it in the first place, in addition to its having a VHS recorder/player). The down side is that this model has now been discontinued (in favor of the 28V, DVD only).

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#18823 - 10/31/11 10:18 AM Re: Panasonic DVD Recorder Woes [Re: alternaut]
grelber Offline


Registered: 08/05/09
Loc: North of 49th ||
Originally Posted By: alternaut
Thanks for the update. It's interesting that you find that much of a difference between these brands. I wonder if it's systematic or just an odd coincidence.

It's definitely not a coincidence; it is definitely systemic.
I tried out 3 different exemplars, all with the identical issue.

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Moderator:  alternaut, cyn