HD radio delay

[Nonick22]

I searched the forums and i was unable to find this topic already but feel free to move this to the correct location.    I have spent many hours (as most of us have) setting the timing on my lights to be perfect with the beat of the music.   When I ran my Halloween show with speakers and listened on my radio everything was perfect.   Then I got a new truck.  (2014 Toyota if you were wondering).  When i listened to that same show the audio was off by almost half a second making it look like a foreign movie.  Has anyone seen this issue yet and how can it be resolved.  As more and more new vehicles come out with HD radios this could be a big issue.

[radioguy1007]

I was a commercial broadcast engineer for many years and do understand that HD radio caused the transmission of the analog portion to be delayed to allow for time for the digital translation to occur.  The reasoning for this is that if the HD part of the signal would drop the radio would switch to the analog signal and there should be no jitter of the sound.  But this was done on the broadcaster's end and not in the individual radios.  If Toyota is doing something different, then this is a HUGE problem if the rest of the auto industry follows.  Here is a simple test - take a standard FM radio in your truck and listen to the same station as your truck radio.  Change between HD stations and non-HD ones.  If the sound is out-of-sync on a non-HD station, then Toyota has done something in their radio that is not good!

[Nonick22]

During the show i had a small hand held non had radio with headphones connected to the radio.  (little 10 pos).  I also had the truck on with the radio listening to the same channel (my channel)  there was a delay in the radio from the truck that was not in the headset of the other one.

[Mega Arch]

During the show i had a small hand held non had radio with headphones connected to the radio. (little 10 pos). I also had the truck on with the radio listening to the same channel (my channel) there was a delay in the radio from the truck that was not in the headset of the other one.

That stinks. Most will probably think it's our broadcasting.

Edited November 20, 2014 by Mega Arch

[k6ccc]

Hate to tell you this, but since the problem is in the new vehicle radio, there is nothing you can do as the content provider to fix it.  Even if you adjusted your timing to work exactly right with your vehicle radio, it would be wrong for almost everyone else.  Even other people with a radio that does the digital signal processing (even for an analog FM signal), the delay time would likely be different for different radios.

 

Check the manual for your radio to see if the DSP can be turned off when listening to an analog FM signal, but if not, you are screwed.

 

I'm going to make a guess, that you are right that this is going to become a larger problem as time goes on.  It will be interesting to see if there is enough user feedback to get the radio manufacturers to add the ability to defeat the delay by the end user.  Off hand, I doubt we as light show people have enough of a voice, and unfortunately the drive in theater industry is almost dead or they would be screaming about this issue since many drive in theaters went to FM broadcast years ago for the movie audio.

[radioguy1007]

I just consulted with a friend of mine that is still in the commercial broadcast business as an engineer and he said the HD transmission is delayed by more than a half second - he said more like 10 seconds.  So Toyota must be doing some sort of DSP (digital signal processing) in their radio causing the half second delay.  In any case, this is not good news.  If it was an HD issue, I'm sure the demand for an HD low power transmitter from us hobbyists would be huge - and LOR could put in a "HD delay" function into their software. 

[Nonick22]

if toyota is doing it then how many other compainies willb e doing it aswell.   I wills ee if there is a way of turning that off in the toyota but the adverage person viewing the shows would not have turned that off.

[Mega Arch]

....... Then I got a new truck.  (2014 Toyota if you were wondering).  When i listened to that same show the audio was off by almost half a second making it look like a foreign movie...... .

Take the Toyota back. I drive a new Ford 1/2-ton and besides running and looking great, it plays my display perfectly. LOL

[radioguy1007]

Well, I guess we will have to tell our show visitors with new vehicles that if the sound does not move with the lights, then they need to listen in with "A Japanese Transistor Radio" (Alan Sherman's 12 days of Christmas song).  Or go back to blasting music with speakers and anger the neighbors.  But that does not work well in places like here (Wisconsin - 21 degrees outside currently).

[Steven]

The stock radio in my Chevrolet Volt has a "rewind" button that lets you pause or rewind up to 20 minutes of live radio. Fortunately, if you don't use this, it doesn't delay like your Toyota.)