How loud is loud?

I may be wrong I'm crap at maths, but isn't db based on a logirthic scale? I once knew how to work out, but forgot that now...

As I said expsoure to over 105/110db can do permant damage to your hearing. Best wear ear plus eh? I'm sure a sounds enginner will know this...anyone?

Originally Posted by bluethunder

I may be wrong I'm crap at maths, but isn't db based on a logirthic scale? I once knew how to work out, but forgot that now...

As I said expsoure to over 105/110db can do permant damage to your hearing. Best wear ear plus eh? I'm sure a sounds enginner will know this...anyone?

Sound Pressure Level is measured in dB and is indeed calculated on a logarithmic scale due to the wide spectrum of pressures associated with the sound.

SPL= 20log(recorded pressure/reference pressure) where the reference pressure in air is 20 micro Pascals.

3dB represents a doubling in sound energy but for every doubling of distance away from the source the level also drops by 3dB. Hence why there is so much confusion about sound levels.

When i did a trackday recently at snetterton they measured mine, it was 102db cold without a baffle, i got pulled in later on in the day for it being too noisy and re measured and it had shot up to 111db as it was hot, this is a pointy with a high level ccc can. You might get away with a db killer in the end and do it cold.

mine has a race micron so i think i might get kicked out, it doesnt have a fitting for a baffle

[northwind]

Mine doesn't have provision for a baffle either, but I bought one off Ebay which fits in with a bolt, just had to drill a wee hole in the neck of the can. It's pretty rubbish but it does take some of the volume out of it (I've got another which I only use for MOTs which is more or less a cork, the bike barely runs with it in)

Brother-in-law just got a new can for his GSXR 1000.

He has yet to ride out with it on but goodness knows how many times he'll get stopped the first time!

I wonder how loud my viper can will be? I guess if the da baffle is then it should be okay for track days right?

[squirrel_hunter]

To echo (fnaaar fnaaar) what has been said already I took mine down to Castle Coombe to be tested before a possible track day. I failed at 110db, but can't remember their limit.

The test was done with the bike at 3/4 revs 1m back and off to the right at about 45 degrees. They don't count over run pops (or I'd be off the scale) just an average. By the sounds of things all track are going to be slightly different so best get yourself down there for a check. Alternatively a db meter costs c.£30.

Originally Posted by bluethunder

I wonder how loud my viper can will be? I guess if the da baffle is then it should be okay for track days right?

.... its loud and very deep.. with the baffle out.. the baffle takes away the rumble.
i did however do a track day a mallory with the baffle out.. no one said anything plus twins arnt as irritating to the ear as IL4 when they scream past