Sound Generator

[JellyCat]

Thanks bubuski, that's an excellent post!  Just nipped out to see if I can spot it on my mk5 GTI, but weird can see it (guess must be no-UK versions that have it).

Will be interesting to see the new electronic one installed on the Mk6 GTI (think I'll ask the dealer to point out when I nip back to check out a car with ACC - going back to compare with and without ACC)

[jv]

what's electronic about it? looks like the same as on some bmw engines where there is pipe from the engine to the firewall - just transferring noise towards the cabin

[JellyCat]

Reviews all state "electronic" sound generator it's bugging me need to find out more info (will report back after talking to VW tomorrow)

[bubuski]

I curious too now. I will be watching this to see what you find out.

[AlanD]

Thanks bubuski, that's an excellent post!  Just nipped out to see if I can spot it on my mk5 GTI, but weird can see it (guess must be no-UK versions that have it).

FYI

UK MK5s never got the new TSI engine from that picture, I know the yanks did and I'm guessing Germany ? ?

All UK MK5 had the standard FSI engine (which came in 2 engine codes AXX and BWA) and will look like this:

[mac7]

Reviews all state "electronic" sound generator it's bugging me need to find out more info (will report back after talking to VW tomorrow)

I bet the 'electronic' bit refers to the fact that the computer decides when to adjust an electrically driven actuator which alters the inlet air or exhaust gas path through the manifold or downpipe in some way to take advantage of a resonance. Or something.

[JellyCat]

I'm betting it's not a pipe, nor is mechanical in nature. Technology is available that can either block out or amplifies certain sound frequencies (used on some planes in biz class - Bose headphones).

It's been around for a long time (was even demo'd about 15-20 years back on a crappy BBC tomorrows world program cancelling out sounds from a crappy Rover (i.e turn on, and it cancels out the sound waves by effectively jamming them).

Therefore you could do this in the Golf to pick and choose sounds plus amplify the nice deep and base like sounds electronically without needing anything to channel sound from the engine bay and therefore not mess up sound insulation etc etc (prob less cost to implement too).

Reviews seem to point to this, I've got a call out to dealer who's finding out more info for me.

[mac7]

I'm betting it's not a pipe, nor is mechanical in nature. Technology is available that can either block out or amplifies certain sound frequencies (used on some planes in biz class - Bose headphones).

Yeah, but to output the amplified frequencies would require not only an amplifier but also a speaker. Maybe on a high end Merc or something, but not a Golf.

It's more likely they'd have a flap or a hole into a resonance chamber or something which mechanically changes the 'note' of the exhaust in a similar way to how musical wind instruments work.

without needing anything to channel sound from the engine bay and therefore not mess up sound insulation etc etc (prob less cost to implement too).

I'm sure there is no pipe or other conduit for sound into the cabin - it would make control of all engine noise near impossible. And gas the occupants. Remember too, most journalists are just regurgitating what they read in the press release.

[jv]

how it works in bimmer land in case you are interested

http://www.zpost.com/forums/showthread.php?p=1501071

[bubuski]

how it works in bimmer land in case you are interested

http://www.zpost.com/forums/showthread.php?p=1501071

For what its worth, it is a similar setup in my Canadian car.