I have a 9th generation Pioneer Plasma and if I use the Optical SPDIF out, to any DAC the resulting analogue signal is very low.
If listening to music content it fills my room but, a little more, if watching a concert for example would be great.
When I was fixing TV's for a living, the Digital out always, no matter what Manufacturer, seemed low to me.
I was thinking of using a cheap DAC chip, using an OP Amp to raise the analogue level to say a good 2V rms and then A to D-ing the signal using a circuit similar to what must be available at the O/P of the average Minidisc unit.
Thoughts and any other possible solutions greatfully received.
P.
If listening to music content it fills my room but, a little more, if watching a concert for example would be great.
When I was fixing TV's for a living, the Digital out always, no matter what Manufacturer, seemed low to me.
I was thinking of using a cheap DAC chip, using an OP Amp to raise the analogue level to say a good 2V rms and then A to D-ing the signal using a circuit similar to what must be available at the O/P of the average Minidisc unit.
Thoughts and any other possible solutions greatfully received.
P.
Why not just add some analog gain after the dac and then go into your power amp?
Why do you want to re-digitize the audio with an ADC?
Why do you want to re-digitize the audio with an ADC?
Well, it's only the TV Input to the DAC which gives low O/P so increasing Gain after the DAC would give me too much on all other I/Ps to the DAC. CD, USB etc etc.
I also don't really want to change the 'sound' of the DAC which adding an extra stage after it could do.
I have run out of Analogue Inputs on my Amplifier so the Digital Out from the TV is prefferable for convenience.
Whereas I still have several Digital I/Ps spare on my DAC and the TV is already plugged into it anyway.
There are DSP chips that could receive the TOSLINK from a TV, digitally increase the volume level, and then digitally send the audio on to some other digital device. No need for DACs and ADCs in that case. SQ should be much better too.
This thread should probably have been posted over in the 'digital line level' sub-forum. That's where there are a number of threads about DSP chips and or boards that might work for your purpose.
For example: low cost ADAU1452 china board..
Searching the forum for threads containing the letters 'ADAU' (without the quotes) will turn up a few more. Please note that Analog Devices makes a series of DSP chips that have part numbers starting with ADAU.
For example: low cost ADAU1452 china board..
Searching the forum for threads containing the letters 'ADAU' (without the quotes) will turn up a few more. Please note that Analog Devices makes a series of DSP chips that have part numbers starting with ADAU.
Interesting problem. Of course I have to ask:
"Is the TV volume down?"
That's just the obvious thing that jumps to mind. TV model dependent often the digital out is a fixed level not affected by volume controls and such - even the analog outs were that way on older TV. But the low digital level just makes me wonder is there isn't something in the TV software controlling it. Volume, Night time mode, DSP or something. You've poked around the menus looking for audio setting, right?
"Is the TV volume down?"
That's just the obvious thing that jumps to mind. TV model dependent often the digital out is a fixed level not affected by volume controls and such - even the analog outs were that way on older TV. But the low digital level just makes me wonder is there isn't something in the TV software controlling it. Volume, Night time mode, DSP or something. You've poked around the menus looking for audio setting, right?
Pioneer PD-5090.
Thanks for the suggestions, but yes, been through all the Menus. Used to fix these for a living !!
Digi Out fixed Volume.
As I say, I used to find that on all modern Flat-Screen TV's the Digital Out is always very low in level once D/A'd.
Used to do Samsung, LG, SONY, Philips, Panasonic etc etc. All seemed low to me.
Looking at the DSP chips suggested (thanks) looks, at a cursory glance that I'd need some sort of control logic to alter the level ?
Way beyond my pay grade !! Sorry.
P.
Thanks for the suggestions, but yes, been through all the Menus. Used to fix these for a living !!
Digi Out fixed Volume.
As I say, I used to find that on all modern Flat-Screen TV's the Digital Out is always very low in level once D/A'd.
Used to do Samsung, LG, SONY, Philips, Panasonic etc etc. All seemed low to me.
Looking at the DSP chips suggested (thanks) looks, at a cursory glance that I'd need some sort of control logic to alter the level ?
Way beyond my pay grade !! Sorry.
P.
The ADI Sigma DSP chips are programmed with SigmaStudio. There is a thread with links to a how-to for that somewhere in the 'digital line level' sub-forum.
SigmaStudio(R) | Analog Devices
SigmaStudio Tutorial with the 3e Audio DSP
SigmaStudio(R) | Analog Devices
SigmaStudio Tutorial with the 3e Audio DSP
Thanks for your reply. The low level does seem strange. What would be the purpose?
Can you play back an MP3 or other music file on the TV and compare it to digital playback from another source? Your estimate of the difference would be interesting to learn.
Can you play back an MP3 or other music file on the TV and compare it to digital playback from another source? Your estimate of the difference would be interesting to learn.
Just read this and I have never experienced this. The not so old OLED TV is connected to an FDA and there are no volume differences with other sources.
Are you sure it isn't a setting? Since newer TV's have a microphone (WHY?) some can adjust volume to the noise in the room as a bonus.
Are you sure it isn't a setting? Since newer TV's have a microphone (WHY?) some can adjust volume to the noise in the room as a bonus.
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