I have found another rather technical document about AC3 downmix.
http://www.qualisaudio.com/documents/TechNote-4-5-6-2013.pdf
It isn't really an easy thing

Zitat von Knorpi

Great! This must be an article for people who develop downmixing
algorithms!

When I watch a TV channel with AC3 audio and I switch the downmix on, the voice sound is getting louder on my AV receiver 5.1 setup. So this is really strange that in your case it is the opposite.
What happens if you let the Samsung TV to do the downmix? I am assuming the TV can decode the AC3.

Zitat von Knorpi

Well, when I let the Samsung TV do the downmix, i. e. select the *.mkv file with the Samsung GUI and let it play, the sound is perfect!
Voices can be understood clearly, while effects still are loud, but not much too loud so that you have to quickly grab the remote and decrease the volume.

Not sure if I got you right about changing the volume with AV receiver.
Well the authors certainly would like us to listen to the movie at predefined loudness, but I think the loudness ratio between each audio channel is the thing which if kept will still produce the sound as intended.

Zitat von Knorpi

I see, but I also believe that the authors made the volumes for the people who watch the movie in a cinema. At home the range of loudness should be somewhat compressed.
But when it comes to that you cannot hear the dialogues while the effects are much too loud, I believe that there must be something wrong with the downmix algorithm.
My TV shows how you can make a good downmix, while the dreambox fails to transport the dialogues or center channel correctly. But I don't know who is to blame...

Of course you are right that this is a job of the component which does the downmix.
But it will not be easy to prove it isn't done right.
Using a TV as the measurement tool is probably not the right path.

Zitat von Knorpi

Ok!

Comparing a movie audio which goes via two different paths without knowing how they were altered by the Samsung SW, doesn't help either.

Zitat von Knorpi

Sure! I also believe that there are complex dependencies. I only want a solution for my situation.
I am on the way to get an AC receiver and a surround system and I am sure that the problem will disappear then. But strictly spoken this isn't a "solution" to the downmix problem. It's just avoiding it...

So this was the second part

PiGeon

Zitat von Knorpi

Thank you very much for this posting. It's the only one in this thread that gave my some explanation. I also studied the article you pointed me to. After reading the article, I think that the downmix processing in the box doesn't mix the channels as expected.
You're right when you say that this is not the original sound anymore, not the sound intended by the authors.
However, this must even hold when you change the channel volume with an AV receiver.
I may still be wrong, but I believe it would be the job of the component that makes a downmix to correctly map the 6 or more channels to a TV's stereo 2.0 setup.

I was having an offline discussion with Knorpi, we agreed on pasting it here so anybody can read it and hopefully we get some statement from DM developers.

thanks

PiGeon

PS: please avoid off topic discussions
PS2: this is first part

also, jetz brauchen wir nur ein Plugin, der a photo nimmt und nach HVEC oder andere movie format umwandelt (nur einen full frame) und dann drueckt play und danach schnell pause drueckt und dann das selbe mit another photo

kann es Jemand bitte ins BFUsprache uebersetzen?
Heisst es, wer Pictures in UHD gucken will, soll fuer neue HW warten?

Howto: Bootlog bzw. Log erstellen

Zitat von root1980

Python sind Böhmische Dörfer.

Das ist nicht wahr!
wenn es wahr waere wurde ich mich in python sehr gut auskoennen

Du hast nicht geschrieben wie weit der gelbe balken war, so es koennte sein dass es vor dem systemd start passierte.
Dann ist es nicht in der journalctl log zum finden.

beispiel:

journalctl -b /media/hdd/boot.log

das speichert alle log eintraege seit letzte box reboot.

ich meinte der in root home
ich hab mich erinnert dass ich es erstellte weil der midnight commander in putty nicht laufen wollte

du kannst es versuchen folgende befehle zu starten
wenn es nicht hilft du kannst es immer loeschen

Zitat

#set the xterm mode
"TERM=xterm" >> ~/.profile
#check actual profile
cat .profile
#load profile
source ~/.profile

Alles anzeigen

erste thread der DM900 forum lessen?
Howto: Bootlog bzw. Log erstellen

was bekommst du zurueck nach diese befehl?

cat .profile

mit folgende command kannst du es sehen

journalctl -b

besser vielleicht ins eine datei umleiten

journalctl -b /media/hdd/boot.log

Ich befuerchte ohne logs wird dir niemand helfen koennen.

cross reference http://www.i-have-a-dreambox.c…thread.php?postid=2198977

Ich habe Plex entdekt, als ich damals nach einem Audio/Videothek server SW suchte, daher benutzen wir auf unsere dreambox den DreamPlex plugin.
Inzwischen gibst auf them server auch Photothek.

http://wiki.blue-panel.com/index.php/DreamPlex_(en)

Have fun!

@Knorpi

A simple search in any search engine for "ac3 downmix central voice" gives you back many results to understand that this isn't a rare issue.
I bumped into a nice article about this https://www.howtogeek.com/2189…n-your-hdtv-is-too-quiet/

After reading the article I wouldn't call it an issue anymore but rather a "by design" thing.

As it was already mentioned Samsung might have implemented dynamic range control (loudness normalization) for their media player which could make the voice/central channel louder in comparison to the other channels to overcome the "issue", but then you are not listening to the original audio anymore, not the one from the authors.

Our dreambox is since ever connected via optical cable to a 20 years old AV receiver (no HDMI).
It is also connected to TV via HDMI, of course. TV is 10 years old so no ARC (Audio return channel)
The AV receiver remote is able to switch on the TV, which sends a wake-up command to the Dreambox via HDMI-CEC.
We always power on the AV receiver and listen to the TV audio through it, TV is muted all the time.
So we control the audio loudness via the AV receiver remote.

I hope that after we switch to a new receiver (with HDMI inputs), we will be able to use the Dreambox remote control to control the loudness via HDMI-CEC (Dreambox > AV receiver). I also hope Dreambox will be able to power on or wake both the AV receiver and TV. I also plan to replace the FM radio which we also listen on AV receiver by Enigma WebRadioFS plugin. I hope all this will finally allow us to use only one remote and mainly the Dreambox one.

We do not use the AC3 downmix and send the Dolby Digital audio to the AV receiver as is. Even through both the audio types Mpeg/PCM stereo and AC3 go through the AV receiver, there are quite huge differences in loudness on different TV/SAT channels.
The TV/SAT channels with MPEG audio are generally louder then the ones with AC3 audio, our old AV receiver doesn't have anything like automatic volume level control, which would keep the loudness level automatically, so we need to adjust the loudness quite often, after changing to different TV/SAT channel.
So you better buy an AV receiver which can do the Automatic Volume Control too.

regards and sorry for the English, but I wasn't somehow able to switch to German today.

Zitat von puffy

ja aber dann muss 2 kabel und kann trotzem nur bis 8 modulatore wenn er eine multischalter hatt reicht eine kabel weil wenn 8 modulatore auf die ebene 1 werde die ebene 2 nicht gehe so ist

Ich wolte es Dir per PM schreiben, aber du hast PM blockiert, so schreibe ich hier ein OT.

Kannst Du bitte kuerzere Saetze schreiben?
Ich weis nicht wie die Deutsche board Benutzern, aber fuer mich als nicht Deutche, ist jeder deine Antwort wirklich ein Raetzel.
Es kann Niemandem helfen wenn er es nachtraeglich lesen wird.

danke ums Verstaendniss

congratulations!

Zitat von st@n

Gibt es dafür eine Begründung?

Kann ich mir gar keine real life scenario ausdenken in welche brauchte mann zum SPDIF was anderes als zum HDMI schicken.
Obwohl koente sein das mann ein TV/Bildschirm hat der nur spezifische signal verarbeiten kann, sagen wir PCM 2ch und neben auch ein AV receiver, welche kann alles vertragen.
Und wen mann moechte kein AV starten, egal aus welche grund (zu faul oder Think green laune), AUDIO kommt zu TV via HDMI, und mann hoert es auch.

In jeder fall wurde es bedauten es paralel zu machen und wer weiss ob es ueberhaupt HWweise moeglich ist.
Kann sein dass der digital zum optik wandler nimmt der audio signal aus der selben quelle als HDMI kabel und da ist kein andere digital AUDIO quelle zur verfuegung.

Ich denke er meint der symbol rot gestrichene cursor tasten, welche auftaucht wenn der knopf keine funztion hat.
Also meine meinung nach, hat er keine HDD drin oder nicht richtig konfigurirte ein.