Corner-entry "bang" in Friday practice; questions

[WillerZ]

At Silverstone on Friday practice 1 we stood by the entry of Luffield, where the drivers have to lift and change down. As they do so there is an almighty bang from the car, a short time after they lift off the throttle.

What causes this?

Why is it that I can't hear it on the TV coverage when in real life it's a lot louder than the normal engine noise?

Why is it more severe on out- and in-laps and less-severe on hot laps (or is the difference in my head)?

[SectorOne]

sound barrier obviously.

no but seriously, you are talking about the fast right hander right? Probably a downshift that you here there.
I think i heard something about Stowe corner where the car changes direction so quickly the sound is lagging behind just a little bit.
Maybe there´s something of that effect into Luffield as well.

[bhall]

Does it sound something like this?

[neilbah]

i was telling my friend yesterday how the TV really gives you no idea what they sound like, on the pit lane limiter they make one hell of a rough sound. The gearbox itself seems to make a decent bang as they accelerate hard. I thought the sound you are reffering to is overrun on liftoff/missfire, maybe unspent fuels being ignited. The driver probably coasts a little more on in/out laps so you hear the effect more?

[timbo]

I've heard that bang on the street-demo F1 event. Yeah, it's very impressive, but it is also very hard to capture. if you ever compared a gunshot in real life and on camera, you'd notice that such sounds are very hard to record.
As to why it doesn't happen during hot laps -- probably they lift less/don't downshift?

[WillerZ]

Thanks all for your thoughts.

It definitely seemed more like a shock wave from a detonation than anything else I've heard elsewhere. Although it has been a long time since I heard any detonations, thankfully!

My guess was spent fuel igniting in the hot exhaust.

Sadly I didn't think to record anything at Luffield (and we were up in the stands so I don't know how well it would have worked). I did record some in FP2 at Maggots – http://tldr.nomzit.com/post/54363513511/singing-engines – the iPhone voice memos app did a surprisingly good job, but like the TV coverage the bangs are almost entirely missing. I wonder if it is because it is a detonation shockwave and it moves the coil and magnet of the speaker in the same way simultaneously.

[SectorOne]

TV cans the sound massively for the commentators.

[Cold Fussion]

TV cans the sound massively for the commentators.

They do, but if the audio equipment was capable of capturing the full range of sound then it probably would, and to anyone who has ever attended an F1 race (or even any motor-race probably) it is clear that it doesn't. I attended the Australian GP for the first time this year and it is quite surprising how different they sound, especially when pulling out corners low in the rev range, they sound very 'raspy' which the cameras don't capture at all.

[astracrazy]

ye i sat at becketts this weekend and they snap crackle and pop like mad when going into chapel. The tv makes them sound so flat when really they make a full range of tones - i don't understand why the tv is so far behind with this when mobile mics are picking up the full sounds. I feel sorry for anyone who hasn't been to a grand prix, the overall loudness and range of noises, you really miss out on tv

the noise in quali when they are flat out through maggots is quiet amazing, they scream

i'd imagine some of the pops/crackles could be unburnt fuel? some of the blowing sounds the engine overrun (ebd or what is allowed now), the gearbox (it seems that causes it but it might not be) seems to cause some bangs or thuds on low downshifts and upshifts

I'll have to upload my videos sometime, there quiet big so its a bit of pain lol

[WillerZ]

the noise in quali when they are flat out through maggots is quiet amazing, they scream

i'd imagine some of the pops/crackles could be unburnt fuel? some of the blowing sounds the engine overrun (ebd or what is allowed now), the gearbox (it seems that causes it but it might not be) seems to cause some bangs or thuds on low downshifts and upshifts

Do they still make the bangs in quali and the race? I was vaguely wondering if they were injecting extra fuel in free practice for engine cooling when illegal maps and excess fuel consumption aren't problems. If it actually extends the engine's life, as Renault claim, I'd be doing it.

[SectorOne]

They do, but if the audio equipment was capable of capturing the full range of sound then it probably would, and to anyone who has ever attended an F1 race (or even any motor-race probably) it is clear that it doesn't. I attended the Australian GP for the first time this year and it is quite surprising how different they sound, especially when pulling out corners low in the rev range, they sound very 'raspy' which the cameras don't capture at all.

You will get some of that raspy sound if you watch broadcasts in natural sound.
It´s like night and day compared to your average commentary broadcast.

And in the big picture it´s irrelevant to have equipment to record the full sound when it´s played through the built-in one inch speakers your TV comes with.
Some have a proper sound system but most definitely do not.
The best you´ll get today is watching with natural sound. Totally different to the canned sound on commentary.
You can get a small glimpse of it during commentated broadcasts when they talk to Ted or Gary for example, their background noise is uncanned.