Stereo Tool

Hi,

I just got my belkin tunecast 3 working with stereo tool to display RDS and RT information, however I wish the RT field to be updated with the now playing info of Mediamonkey (or Winamp). Is that possible? (would be as easy as capturing the window text and putting it in the text box, I don't have the experience though to automize...)

- Koen

Congrats!

If you're using Winamp and Stereo Tool as a Winamp plugin, see the solution below.

If you're NOT using Stereo Tool in Winamp or a compatible player, see viewtopic.php?f=6&t=26&p=123&hilit=artist#p123 .



For Winamp and maybe some compatible players, there's now a new option \W to include the currently playing song in the RDS info. So there's no need anymore (in players where this works) to use NowPlaying plugins etc.

RDS: Usage:
\W"winamp formatting string"

Example:
\W"PLAYING %artist% - %title%"

Put | in front of it to split the text, so for example:

1.5s:STEREO/1.5s:TOOL/|\W"PLAYING %artist% - %title% "

Note: It is left to Winamp to parse the string and resolve all the data. So other players - even if they support part of the Winamp plugin interface - might not support this. In that case an error message should be displayed instead.

Hi, thanks alot!

Mediamonkey didn't work with the method from the second post, but using AIMP with an input file worked great! Thanks alot!

Now everything that's left is a lot of tweaking, since the sound is a bit distorted. But before, I didn't think it would work with such a cheap fm broadcaster (bought it for like 15 euros)!

*EDIT*: The distorted sound was introduced by the loudness slider. Disabling that made it sound just perfect! I'll post a tutorial on how to get your belkin tunecast 3 working with rds soon if anyone's interested!

That's true (Loudness) - in many countries all the stations use something like this to sound as loud as possible (which really hurts the sound quality), in other countries this is not done AT ALL.

If you're not intending to sound 'as loud as possible', leave Loudness off (or at least at a low value, up to about 2.0/2.5).

I've uploaded the preset here. (deleted, now in this topic)

If you experience alot of distortion or bad RDS reception, it might be that the output level of your soundcard is too high. Just lower the volume. I've set it to 0.0096 (very very low). Be sure to enable direct soundcard access if you haven't already, and put your belkin tunecast 3 in mono mode by holding the left button on the top for a while until it bleeps (should give an indicator stereo -> mono while doing that), full guide will follow

If I just use the stereo mode of the belkin, and do not use direct soundcard output of stereo tool, but rather use stereo tool merely as a DSP processor, the sound is not that bad, so I don't know if it's the fault of the fm transmitter limiting in some way. It just seems that after the loudness effect, some frequencies really get boosted beyond some limit where it starts distorting. So where I limited some frequencies from becoming distorted before with the clipping, the loudness effect "ignores" that?

But still I'm not that experienced, so not sure.. :p

In that case it's already a miracle that the RDS output is working.

Basically, the RDS signal is some high frequency tones around 57 kHz, locked to a pilot tone at 19 kHz.

A stereo coder (which is apparently present in your transmitter) _should_ filter out anything above 15 kHz, then create a pilot tone at 19 kHz and put the stereo signal at 23-53 kHz.


So there are 2 problems:
1. The RDS signal should not be present in the output signal (!)
2. If the filtering is NOT perfect (the fact that the RDS signal is still there would indicate that), both 19 kHz pilot tones will get in each others way. (And since they'll never be exactly 19 kHz, this may lead to very strange effects).


Can you turn the stereo coder of your transmitter off and use the one in Stereo Tool instead?


Have you tried how it sounds if you don't send the output through the transmitter, but listen immediately on the sound card? The output that comes out of the transmitter should be nearly identical to the output from the transmitter. If you don't hear distortion there, there shouldn't be any in the FM signal.

After Loudness, ANY extra clipping that's done will immediately cause a lot of distortion. That's because Loudness pushes everything up to it's limits.

The belkin does not filter frequencies in any way I've noted. If I turn stereo mode on while having fm broadcasting on in stereo tool, I do get RDS now and then, and the volume jumps up and down alot (probably because of that interference of the two pilot tones?). So I guess the sound is not filtered, and is just broadcasted by the tunecast in 192 khz anyway (weird though).
That's exactly what I'm doing. If I turn on the pilot, my radio detects it as being stereo without sending a stereo encoded signal at all though, and that introduces a bit of white noise in the background. If I turn on the stereo coded signal then, sound is fine, still more noisy than when the pilot tone is turned off, but a panning test shows that the left and right channels are encoded in the right way...

But still, the output strength of the fm transmitter seems to be limited, since I can only put my sound card to about 10 % of the volume, anything above that starts distorting. And if I use the stereo mode of the fm transmitter (and the normal non-fm output of stereo tool), I can set it to about 30 %. Which I find weird...

Anyway, for my application it's enough, I just wanted to use it for my pc upstairs to play some music to the radio downstairs, and I can even read what's playing without having to run upstairs... so (I was surprised at the range, but the dc input seems to work as an antenna :p)

If that's your goal, That might make sense - you cannot hear the signal above 19 kHz but if it's not filtered out, it's still there. And the pre-emphasis filter in the transmitter (which amplified higher frequencies, because the receiver does the opposite) might increase the volume of the signal about 19 kHz a lot.

Is the amount of stereo depending on the volume of the pilot signal? because your post about the pilot signal reminded me of that... because now that i listen through stereo tool's encoding, and compare it with the original encoding done by the fm transmitter, it seems that stereo tool's signal produces too much stereo and all the mono sounds, like vocals and bass are put to the background.

There is this slider for the stereo volume but i can't move it, is that only for the full version?

Also, when I set the angle to 180 degrees under stereo image, the sound is much louder and the voices are back on the foreground. Is 180 degrees the same as inverting the signals of one of the channels?