[inglisd]

I have an older model Panasonic plasma TV (TH-46PZ80U) and want to run the Toslink digital audio output
through my BDA-3.  I can only get a lock when the BDA-3 is powered on with Toslink selected
and then turn on the TV.  If I change channel, or after a short delay (< 30 sec), the lock disengages
and the Opto/Toslink led turns red.  I have used the same cable connected between BDA-3 and the output of
my Cambridge CD/DAC.  I tried a different cable: same result.

BDA-3 details:

[James Tanner]

It sounds like the TV is not sending digital zero's (so no signal) when there is no content so the BDA-3 will lose sinc.

james

[inglisd]

I am curious how I would test for an "empty" digital stream from the TV toslink.  The CD/DAC
sinc persists when in pause / stop mode, so you are saying that even then there is a bit stream of 0's ?

[James Tanner]

Its just a guess because the only time I have seen a loss of sinc is when no digital signal is being sent. 

james

[NekoAudio]

Yeah, silence over S/PDIF is not a flat signal, it's actually still switching up and down. Versus when an S/PDIF transmitter is completely turned off, then there is (except for noise) a flat signal.

If you see a sync light on the S/PDIF receiver (e.g. BDA-3) then the transmitter (e.g. TV) is still sending a valid stereo S/PDIF signal even if it is silence. If I remember correctly, the BDA-3 can accept up to 24-bit / 192kHz stereo S/PDIF on its TOSLink input.

But it sounds strange to me that you say the BDA-3 has to be turned on before the TV is turned on. There's no way for the TV to know if the BDA-3 is turned on or if it has the TOSLink input selected. Optical S/PDIF is a one-way transmission. Is it possible you have to change a configuration option on the TV? For example making sure it does not try to output surround sound? Have you tried connecting it to a second TV?

[inglisd]

thanks for your post.  I don't have a 2nd TV to try and being an older model, the feature set for
audio is somewhat limited.  I have no problem running all my hdmi sources through the BDA-3 and
then pass through to a single hdmi input on the TV.  Audio is bypassed and routed direct from BDA-3 to
preamp and the TV speakers are muted / off.  However, the cable source (antenna) goes to TV and unless
I can figure out the toslink issue, tuner audio output now routes to preamp aux input over RCA connection. 
The TV digital audio out spec'd in the manual states "PCM / Dolby Digital, Fiber Optic".
Could be time for a TV upgrade ...

[Stefan_DR3]

I have the exact same TV in my bedroom system and send the optical out to a Yamaha receiver.  Works fine with HDMI sources but I have never tried the antenna input.

OK I just tried antenna and see what you're saying.  The PCM audio only works when you first turn on the TV.  If you change channel or the signal drops for any reason the TV stops sending the PCM audio until you cycle power again.  Very strange that this only affects the internal TV tuner.

[inglisd]

thanks for confirming.  Such a shame, the picture this TV produces has been excellent since day 1.
I may try an outboard TV tuner with HDMI out.

[gbaby]

If you see a sync light on the S/PDIF receiver (e.g. BDA-3) then the transmitter (e.g. TV) is still sending a valid stereo S/PDIF signal even if it is silence. If I remember correctly, the BDA-3 can accept up to 24-bit / 192kHz stereo S/PDIF on its TOSLink input.

Toslink can only support up to PCM 96/24 bit sample rate. It was originally up to 48/24.

[alexone]

Toslink can only support up to PCM 96/24 bit sample rate. It was originally up to 48/24.

...then why the BDA-1 has optical inputs which support up to 192/24 

al.

[gbaby]

...then why the BDA-1 has optical inputs which support up to 192/24 

al.

The reason is the specs have been upgraded for Toslink to play 192/24 bit. It now depends on the manufacturer and the cable itself. 

[Stefan_DR3]

I may try an outboard TV tuner with HDMI out.

That's not a bad way to go, and they are quite cheap.  You just have to make sure it's not trying to send Dolby Digital bitstream (the ATSC standard) and PCM will be 44/16 only, so no issue for Toslink!

I thought there might be a firmware update for the Panny TV tuner issues, but I can't find one for this model.

[inglisd]

thank you everyone for the helpful and informative replies. 

My original motivation was to route TV audio digitally to BDA-3 instead of direct SE to
aux of my now very old 11B.  I picked up a BP-17³ last week which affords SE aux input AND
remote volume control and source selection.  I can live without routing through the BDA-3 until I replace
the TV with modernized digital outputs.  Besides, I'm not convinced getting up, taking two steps forward and back to the
11B to manually select and adjust volume and then sitting down again were making any fitness improvements