investigating Supercharger sound

[JG13Wulf]

Don't know if it's normal, but seems quite weird when supercharger start at about 3000 m.

[gulredrel]

bump...

 

Yes, still the case in DCS/2.7.5.10869.

 

Alwayss scares me to death, when the automatic switching occurs and the engine sound increases abruptly.

 

Hope this can be fixed, when the Fw get's some love. The Mossie needs an adversary in combat. The pilot shouldn't die from a heart attack while the supercharger switches into high setting 

[NineLine]

From the manual:
At an altitude of approximately 3300 +/- 200 meters, the supercharger automatically switches supercharger speed from low to high. Try not to fly or frequently change your altitude within this threshold.

Is this what you are seeing?

[gulredrel]

@NineLine That it switches automatically is not the problem. What is weird is the engine sound volume increases abruptly in a sense of digital switch from 0 to 1 and not a mechanical one with a small delay in increase of manifold pressure and rpm after switching gears.

[Nealius]

Same for the other aircraft as well, particularly the Spit and Mustang. The binary and extreme sound change between supercharger off and on is so jarring it literally makes me jump in my seat, thinking a burst of flak just hit me out of nowhere. 

[grafspee]

I know where problem is. Problem lies in sound level difference between different MP levels, this what exactly happens, you climb your Warbird and you loose MP let say you are in A-8 and climbing with throttle wide open, so you start with 1.42 ATA and at some point you hit crit alt so your MP start to drop, 1.3 1.2 1.1 don't know at what ata it switches but at engine sound in the game is like twice quieter then when run at 1.42 ATA, so when supercharger high speed kick in, it sounds like a explosion. In my opinion sound level should not change much until very very low ATA, you can watch Bf-109 flying at airshows at 1.0 or 0.9 ATA and they sounds amazing and in DCS when you do fly by at 1.0 ATA is like hearing glider no sound at all so quiet.

I think that things are modeled correctly how fast and violent this speed switch is, manuals says to avoid being in supercharger switch aera as much as possible so it is not easy for engine.

Watch carefully when he drops power from 55" to 46" i can't here any difference in sound, until he drops RPM.

If ED will fixe it, all this weird explosions during supercharger switching will be gone.

This is another inaccuracy when you cut throttle in DCS sound level is still very high and in RL plane is very quiet 

Watch how not linear sound level changes engine is very loud until throttle is in idle position in DCS there is not much difference in engine sound when you do this.

 

Edited December 27, 2021 by grafspee

[NineLine]

Hey guys can you tell me if you have 'Loud Cockpit Afterburner Sound' checked? And if yes, try it unchecked. Now it shouldn't affect WWII aircraft for obvious reasons, but that might be the issue. Thanks.

[grafspee]

I do not.

[LeCuvier]

I went through several cycles, with the "loud cockpit afterburner sound" ticked and unticked, and I could not hear a significant difference in the sound when the supercharger kicks in.

And I could not hear any difference when the supercharger went off. In my trials, it kicked in at slightly below 2,900 m altitude. In order to find out where it disengaged, I reduced altitude first to 2,700 m and speed to 400 km/h. When I went full throttle I still got 1.4 ata. At 2,600 and 400 km/h I got only 1.2 ata. So I guess the supercharger disengages somewhere between 2,700 and 2,600 m. That's a fairly large  deadband and would help a bit to avoid overfrequent cycling.

Anyway, the option "loud cockpit afterburner sound" doesn't seem to matter in this case.

PS: Twice I changed that option during the mission (ESC/Options/Audio) and twice my screen went black (not immediately). The second time I had to kill Windows with the power switch. It could be a coincidence of course, but I haven't had any instability for many months. So going forward I'll keep my fingers off that tick box.

Edited December 28, 2021 by LeCuvier
kick-in altitude is 2,900 (not 3,900) m

[grafspee]

In case p51 shift down is set 1500ft below shift up alt to avoid frequent shifting. Shift down is very quiet

[gulredrel]

No difference for me with "loud after burner sound" on or off.

Sound volume increases in the same way blowing away my ears  

[NineLine]

Thanks for looking guys, I thought there was a difference, but I must have imagined it, I will ask the team if there is a reason for such a large change in the sound.