Stopped: TV Soundbar
Common TV Soundbars are very expensive or really bad. This gives a niche for DIY. To develop the electronics for a solution with digital input there is know how needed I don't have. To sad :-( What about cooperating?
Common TV Soundbars are very expensive or really bad (because of bad speakers). This gives a niche for DIY.
To develop the electronics for a solution with digital input there is know how needed I don't have. To sad :-(
What about cooperating?
What it should have:
A digital input of audio signals via HDMI CEC. This can control the volume of the connected electronic circuit (audio signal or amplifier) so only the remote control of the TV is necessary for daily use.
After Interfacing HDMI and extracting the signals a microcontroller should generate digital and/or analog audiosignals and a switch signal with which a connexted audio amplifier can be schwitch on and off.
The microcontroller should have at least be able to set treble and bass (tone control). Its values should be stored in EEPROM.
Maybe a simple Raspberry Pi as hardware base would be a good idea.
A dedicated remote control input is just an option but not necessary.
With this hardware it is easy to add a (stereo) audio amp and the personal preferred speakers to get really good sound at moderate cost.
What do you think?
To develop the electronics for a solution with digital input there is know how needed I don't have. To sad :-(
What about cooperating?
What it should have:
A digital input of audio signals via HDMI CEC. This can control the volume of the connected electronic circuit (audio signal or amplifier) so only the remote control of the TV is necessary for daily use.
After Interfacing HDMI and extracting the signals a microcontroller should generate digital and/or analog audiosignals and a switch signal with which a connexted audio amplifier can be schwitch on and off.
The microcontroller should have at least be able to set treble and bass (tone control). Its values should be stored in EEPROM.
Maybe a simple Raspberry Pi as hardware base would be a good idea.
A dedicated remote control input is just an option but not necessary.
With this hardware it is easy to add a (stereo) audio amp and the personal preferred speakers to get really good sound at moderate cost.
What do you think?
Discussie (6 opmerking(en))
Terence Rose 3 jaar geleden
Check out the link below that shows how to use the Rasberry PI
Using HDMI-CEC on a Raspberry Pi - Pi My Life Up
Using HDMI-CEC on a Raspberry Pi - Pi My Life Up
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Dr. Thomas Scherer 3 jaar geleden
There is 1 (in words: one) product which does (a part of) the job:
FeinTech VMA00102
https://feintech.eu/collections/hdmi-audio-extractor-konverter/products/vma00102-hdmi-arc-audio-tv-adapter-mit-lautstarke-steuerung
Maybe if I open this device I can find a signal which shows if a PCM audio signal is send from TV and can use it to switch on/off an Amplifier. This could be a quick and dirty solution with nearly no engineering needed ;-)
FeinTech VMA00102
https://feintech.eu/collections/hdmi-audio-extractor-konverter/products/vma00102-hdmi-arc-audio-tv-adapter-mit-lautstarke-steuerung
Maybe if I open this device I can find a signal which shows if a PCM audio signal is send from TV and can use it to switch on/off an Amplifier. This could be a quick and dirty solution with nearly no engineering needed ;-)
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eduino.io #oetelx 3 jaar geleden
This is almost what you need.
The switching of the amplifier can be done quickly by a a couple of resistors, and a low cost op-amp.
With this level detector you can switch an optocoupler and anything with that output.
You can also try to find a signal inside the device, both will work and are feasible.
Let me know if you will try to make it work. ;-)
The switching of the amplifier can be done quickly by a a couple of resistors, and a low cost op-amp.
With this level detector you can switch an optocoupler and anything with that output.
You can also try to find a signal inside the device, both will work and are feasible.
Let me know if you will try to make it work. ;-)
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Dr. Thomas Scherer 3 jaar geleden
Switching on the base of the audio signal ist not reliable enough.
I think I will order that thing from Feintech and have a look under the hood...
I think I will order that thing from Feintech and have a look under the hood...
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eduino.io #oetelx 3 jaar geleden
Hello Thomas,
My active speaker system uses the input level to switch from stand-by to active.
It has a fast attack (maybe 0.2 sec of some level) and slow release (30 seconds of silence) so it will never turn off by accident.
This can be built with simple parts.
Do you have other experience which suggests it is not reliable?
My active speaker system uses the input level to switch from stand-by to active.
It has a fast attack (maybe 0.2 sec of some level) and slow release (30 seconds of silence) so it will never turn off by accident.
This can be built with simple parts.
Do you have other experience which suggests it is not reliable?
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Dr. Thomas Scherer 3 jaar geleden
I had a similar solution for active speakers already.
Normally it worked okay but in several conditions (long quiet scenes) it switched off.
So I prefer a direct switch.
Using USB-power fom TV is not so pretts because I have an LG OLED which does some jobs to prevent burning in after switching the TV off and keeps the USB-power on for 1 to 30 minutes.
Normally it worked okay but in several conditions (long quiet scenes) it switched off.
So I prefer a direct switch.
Using USB-power fom TV is not so pretts because I have an LG OLED which does some jobs to prevent burning in after switching the TV off and keeps the USB-power on for 1 to 30 minutes.
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eduino.io #oetelx 3 jaar geleden
There are commercial available AV receivers of reasonable quality that can do what you want.
They will route the HDMI signal and extract the audio for you. You can then use the tone control and the amplifier to make it as you like.
Denon/Marantz have equipment for sale.
Some issues appear to have been fixed for high resolution video.
https://tweakers.net/nieuws/180988/denon-en-marantz-bieden-adapter-aan-voor-oplossen-hdmi-issue-bij-4k120-signalen.html
I did some reverse engineering/investigation on a sound bar some time ago. (2017)
https://www.hexnut.net/2017/06/denon-dht-t100-bad-caps-ceramic-caps.html
Using a 25 euro HDMI to analog converter and adding analog bass/treble with an analog volume control would be my way to approach this, not extracting HDMI audio and adding a DSP to do signal processing in the digital domain.
Adding a noise gate (VOX) and an RC receiver (could be an arduino RC5) that matches the brand of TV you have would make it a workable solution.
How much time and money would you like to invest in the project?
They will route the HDMI signal and extract the audio for you. You can then use the tone control and the amplifier to make it as you like.
Denon/Marantz have equipment for sale.
Some issues appear to have been fixed for high resolution video.
https://tweakers.net/nieuws/180988/denon-en-marantz-bieden-adapter-aan-voor-oplossen-hdmi-issue-bij-4k120-signalen.html
I did some reverse engineering/investigation on a sound bar some time ago. (2017)
https://www.hexnut.net/2017/06/denon-dht-t100-bad-caps-ceramic-caps.html
Using a 25 euro HDMI to analog converter and adding analog bass/treble with an analog volume control would be my way to approach this, not extracting HDMI audio and adding a DSP to do signal processing in the digital domain.
Adding a noise gate (VOX) and an RC receiver (could be an arduino RC5) that matches the brand of TV you have would make it a workable solution.
How much time and money would you like to invest in the project?
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Dr. Thomas Scherer 3 jaar geleden
Maybe you are right.
I should buy a normal AV-Receiver and forget the project.
Otherwise: I'd like to build that myself ;-)
I should buy a normal AV-Receiver and forget the project.
Otherwise: I'd like to build that myself ;-)
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eduino.io #oetelx 3 jaar geleden
I would not suggest abandoning the project idea already.
I would however try to get more information about the required electronics and firmware before starting.
Can we find the required chips on AliExpress? There might be a reference design that almost does most of what you want.
If many factories are producing these boxes at low cost the design can not have a large value in terms of the intellectual property anymore.
I suspect that we could find a schematic and maybe some example code that would work.
I would start by buying one of these boxes and checking what is inside. This would only require limited amount of work and money. After that the next step can be chosen.
What do think about the approach?
I would however try to get more information about the required electronics and firmware before starting.
Can we find the required chips on AliExpress? There might be a reference design that almost does most of what you want.
If many factories are producing these boxes at low cost the design can not have a large value in terms of the intellectual property anymore.
I suspect that we could find a schematic and maybe some example code that would work.
I would start by buying one of these boxes and checking what is inside. This would only require limited amount of work and money. After that the next step can be chosen.
What do think about the approach?
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Dr. Thomas Scherer 3 jaar geleden
See my first answer.
This is not what I want nor what other people would like.
Its not a question of money or that I have a stereo set already.
It is a question of making a soundbar (or something like that) with
a really good sound.
Beeing able to select the speaker you like and the amplifier you like.
Reverse engineering of a commercially bilt soundbar is nearly impossible.
This is no option.
What I did until now:
I bought a standard soundbar, cutting both wings with the speakers and just
use the electronics (HDMI-2-Audio and amplifier). I connected that with
a good passive 2:1 speaker set containing a 30cm subwoofer.
It works and sounds much better than the original, but there is still
a problem:
The digital sound processing of such soundbars take the bad bass performance
of the built in speakers in to account and compensate that. So I get a big
bass boost with my 30cm subwoofer which is not what I wanted.
I have to set bass level to minimum to get an acceptable sound there.
2nd: The amplifiers of the soundbar deliver only about 20W of output power
which is way less than the advertised "150W" - nearly all manufacturers
are lying here. The PS of the soundbar delivers 25W max....
So some better amplifiers would be fine.
3rd: Many modern TVs lack of an analog output for sound. And even
if the have one, the TV can't switch on/off an external amplifier.
This is why a DIY hardware would make sense.
This is not what I want nor what other people would like.
Its not a question of money or that I have a stereo set already.
It is a question of making a soundbar (or something like that) with
a really good sound.
Beeing able to select the speaker you like and the amplifier you like.
Reverse engineering of a commercially bilt soundbar is nearly impossible.
This is no option.
What I did until now:
I bought a standard soundbar, cutting both wings with the speakers and just
use the electronics (HDMI-2-Audio and amplifier). I connected that with
a good passive 2:1 speaker set containing a 30cm subwoofer.
It works and sounds much better than the original, but there is still
a problem:
The digital sound processing of such soundbars take the bad bass performance
of the built in speakers in to account and compensate that. So I get a big
bass boost with my 30cm subwoofer which is not what I wanted.
I have to set bass level to minimum to get an acceptable sound there.
2nd: The amplifiers of the soundbar deliver only about 20W of output power
which is way less than the advertised "150W" - nearly all manufacturers
are lying here. The PS of the soundbar delivers 25W max....
So some better amplifiers would be fine.
3rd: Many modern TVs lack of an analog output for sound. And even
if the have one, the TV can't switch on/off an external amplifier.
This is why a DIY hardware would make sense.
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eduino.io #oetelx 3 jaar geleden
Just a quick google : I can find similar devices online for less than 25 euro.
This does not mean that you should buy it, building it is much more fun and you will learn many things, useful for students and engineers if documented correctly. If needed I will assist.
-- Nederlandse tekst --
Ik kan na enige minuten google producten online vinden die precies voldoen aan je eisen, prijs kleiner dan 25 euro. Ik wil best meewerken om een open source gedocumenteerde variant te maken, dat is leerzaam en nuttig voor andere ingenieurs en studenten.
This does not mean that you should buy it, building it is much more fun and you will learn many things, useful for students and engineers if documented correctly. If needed I will assist.
-- Nederlandse tekst --
Ik kan na enige minuten google producten online vinden die precies voldoen aan je eisen, prijs kleiner dan 25 euro. Ik wil best meewerken om een open source gedocumenteerde variant te maken, dat is leerzaam en nuttig voor andere ingenieurs en studenten.
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Dr. Thomas Scherer 3 jaar geleden
Yes you can buy HDMI-Audio-Converters but they lack some important features:
• No control of volume through the remote control of the TV.
• No switching on signal for a connected audio amplifier.
• No sound control (bass, treble)
This features you can't buy in no hardware in the moment.
• No control of volume through the remote control of the TV.
• No switching on signal for a connected audio amplifier.
• No sound control (bass, treble)
This features you can't buy in no hardware in the moment.
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eduino.io #oetelx 3 jaar geleden
You want the audio extracted from the HDMI signals, you can not use the Line Outputs of the signal source (set top box) ?
https://www.allekabels.nl/hdmi-omvormer/1792/1218636/hdmi-omvormer-hdmi-audio-extractor.html
You can use it to generate the analog signals to connect the old HIFI system which has better speakers than a cheap sound bar.
If you like we could reverse-engineer this HDMI box, but rebuilding it will always be more expensive than buying one. It could be an interesting project for aspiring engineers.
-- Nederlandse tekst --
U wilt de audio uit de HDMI-signalen halen, kunt u dan niet de lijnuitgangen van de signaalbron (set top box) gebruiken ?
https://www.allekabels.nl/hdmi-omvormer/1792/1218636/hdmi-omvormer-hdmi-audio-extractor.html
U kunt het gebruiken om de analoge signalen te genereren om de oude HIFI installatie aan te sluiten die betere luidsprekers heeft dan een goedkope soundbar.
Als u wilt kunnen we deze HDMI box reverse-engineeren, maar het herbouwen zal altijd duurder zijn dan er een kopen. Het zou een interessant project kunnen zijn voor aankomende ingenieurs.
(Met dank aan deep-L voor de vertaling)
https://www.allekabels.nl/hdmi-omvormer/1792/1218636/hdmi-omvormer-hdmi-audio-extractor.html
You can use it to generate the analog signals to connect the old HIFI system which has better speakers than a cheap sound bar.
If you like we could reverse-engineer this HDMI box, but rebuilding it will always be more expensive than buying one. It could be an interesting project for aspiring engineers.
-- Nederlandse tekst --
U wilt de audio uit de HDMI-signalen halen, kunt u dan niet de lijnuitgangen van de signaalbron (set top box) gebruiken ?
https://www.allekabels.nl/hdmi-omvormer/1792/1218636/hdmi-omvormer-hdmi-audio-extractor.html
U kunt het gebruiken om de analoge signalen te genereren om de oude HIFI installatie aan te sluiten die betere luidsprekers heeft dan een goedkope soundbar.
Als u wilt kunnen we deze HDMI box reverse-engineeren, maar het herbouwen zal altijd duurder zijn dan er een kopen. Het zou een interessant project kunnen zijn voor aankomende ingenieurs.
(Met dank aan deep-L voor de vertaling)
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Rene-Murten 3 jaar geleden
Yes, certainly a good idea too. However, the following must be considered:
- Because several power supplies are now working in parallel on the mains, the following problems may occur:
- Cross currents via the common GND line (HiFi system and TV);
- A vacuum cleaner or other devices produce crackling noises from the speakers when switched on;
- One would have to optically separate the audio or HDMI signals.
- Because several power supplies are now working in parallel on the mains, the following problems may occur:
- Cross currents via the common GND line (HiFi system and TV);
- A vacuum cleaner or other devices produce crackling noises from the speakers when switched on;
- One would have to optically separate the audio or HDMI signals.
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eduino.io #oetelx 3 jaar geleden
This seems like speculation.
A properly connected sound system will have no issues.
Your vacuum cleaner is not connected to the ground of the sound system.
It is not even grounded but double isolated class II device.
If you have issues with noise then apply a Power Line EMI Filter.
If you have ground loops you can not fix by using a star topology then use ground loop isolation transformers.
A properly connected sound system will have no issues.
Your vacuum cleaner is not connected to the ground of the sound system.
It is not even grounded but double isolated class II device.
If you have issues with noise then apply a Power Line EMI Filter.
If you have ground loops you can not fix by using a star topology then use ground loop isolation transformers.
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Dr. Thomas Scherer 3 jaar geleden
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