I have 128 OFF with the engine off and 128 ON with the engine running.
What exactly does the ON and OFF part mean? Is it as simple as engine
off or on, does it mean the head unit amp is off or on?

I know there is a lot going on with the engine running, engine noise ,vibration and exhaust noise,
but it just does not sound as clean as it does with the engine off. Might just be in my head.

 

I agree with you 100% about the degrade in audio quality when engine is running. Have some music playing, turn bike off and music sounds fuller/richer.

My thought on this is: When bike is going down the road, with the wind breaking up the sound waves from the speakers the engineers thought it would be better to cut some of the "richness/fullness" that gets wasted and make the radio play louder, all because they use an inferior speaker.
I could be full of crap... maybe not...

Or could it just be the harmonics going on when bike is running that suck the good sound that seems to increase when you shut engine off?

I can't remember if my 08 Road Glide suffered this phenomenon.

 

I'm sure your 08 was better, my 08 SG had a better sound system.

 

Timbo has it, been proven the stock hd radio will send less volts out when bike is running on many if not all bin files , which is why there is no way for stock radio to ever be what it should be or until hd creates a flash called {after market guys load this we have quit screwing you}.

 

One thing I thought of is if you are using AVC it has to cut it so it can increase it at speed.
I have found to use it. In the off position it is quieter than having it at four bars at speed. But it doesn't increase it like the pre-Rushmores.

 

Here is what I got from bill at BT...

Hi Barry,

There is some misinformation out there about being able to turn off the internal amp in the radio, that does not actually ever happen, you are just changing the EQ settings when you get the radio flashed. Getting it flashed loads different EQ files that "flatten" out the sound and remove the really high bass/treble boost that HD uses when there is no amp installed.

The off/on bin files exist because HD uses one EQ setup when the bike is off and loads a different one when it is running. Unfortunately the one that gets loaded when running does not sound as good, it is kinda weak. HD did this so the their audio equipment would sound good in the showroom but would not blow up when really cranked up on the road.

Bill

 

With what bill and many other shops have known about low volt output when bike is running is why i keep saying radio can never be right some still think they have got it figured out but how can no bass or treble fad or sounds great when not running and only ok at best when running be cosiderd figured out .