llcoolpass

ill start with the facts and fill in from there the details over time with you guys and gals.

"A weight"ing, slow response, instantaneous, level road[meaning, consistent load], 5th gear [manual trans] ...... oops alright telling you lots of details....to the numbers , batman!

40 mph, 63 dB

55 mph, 66 to 67 db

60 mph, 67 db

70 mph, 69 to 70 db

75 mph, 71 db

100 mph, 75 db

idle; 0mph, 52 to 53 db

measured at passenger front head rest

Pyroibw

that seems a bit high, what meter did you use?

llcoolpass

what measurements did you obtain? or, what would have expected?

I used the radio shack digital.

again, i could tell you there are about 4 things that contribute to noise that a new example of my car wouldn't have to deal with, but taking them away would probably only net at most, at specifically 65 mph, probably 0.5 dB of sound measurement decrease. i didnt want to get into all thethings right now. i wanted this thread to sink in for a while.

please, pyro get back to me. and any one else, feel free to chime in.

llcoolpass

a lot of the tar sound stuff has smeared off/oozed down in the wheel wells, the trim that goes arounf the windshield [look at a picture to see the design] sticks up slightly in the middle of the top, the windows have wind noise [frameless is a *****], and the exhaust is bosal and may not be quite as quiet as stock... also i got me, bigger person and 200 lbs of stuff in car.... once i address these issues, in a scientific manner i will return results. the temperature outside was 50 deg F, it was not windy at all [calm] and it was not raining and car was not wet. 3/4 mark on fuel gauge. asphault highway. occasionally switches to concrete where i noticed the sound jumps 5 dB higher at 60 mph. concrete is the enemy of quiet carness. its also missing the under engine plastic tray cover, and the front fender at the bottom is a little messed up. this stuff cant help. but it's not adding like 5 db! maybe 0.5 db. at 60mph.

there. all my dirty laundry

in the motorweek review, they got similiar dB measurement.

i read a 2009 lexus GS review, and they get much lower highway noise measurements of 63 to 64 dB [A weight obviously] [70 mph] much more like the contemporary to my car [1993] infinity q45 and lexus ls400 can achieve.

switching to four gear at 60 mph for instance didn't much change the db measurement [it was 0.5 dB or less difference]. i tried it just out of curiousity. though, personally, i notice the engine sounds becomes much more noticeable.

this proves what i noticed all along, that from 70 to 100 the car doesn't get much louder, compared to the competition's cars I've driven. its more slow increases in noise.

llcoolpass

popular science nov 1993
lexus GS 300:
60 mph , 73 dB

http://books.google.com/books?id=3oR...0lexus&f=false

llcoolpass

the car has a nice noise though its not obtrusive and its decently quiet and not annoying, but at higher speeds the random wind noise [the almost but quite whistle pitch ] is a detraction. but tires engine everything is smooth sounding. it lets music sound good too. of course, i'm all for lowering overall noise, but hopefully, it wont leave some noise much higher than others. that would start to make it more annoying, even if less noisy.

llcoolpass

eww just found another cool article on car interior noise volume.

http://www.thetruthaboutcars.com/the-art-ofnoise/

so they compare at 80mph various cars [incl many german ], and above I measured at 80mph about 71 to 72 dB. My car is now been on the road since spring 1993, and it's now fall 2009, and the odometer reads 152,000 miles ... so I can't say I'm complaining.

tuan92129

Here was mine from the sound deadening thread..
I guess, the sound deadening didn't really improve anything (except better audio performance, esp low end frequencies)
I'll probably re-measure since i did buy new tires and changed the window seals, and switched from low profile 17 in rims to oem 15 in. since the last measurement.

llcoolpass

ellaborate one what you meant in saying 2800 RPM

and the part with 2300 rpm

tuan92129

The engine was at that particular speed when the measurement was taken. I included that aspect because i could have been accelerating at full throttle, = more engine noise and higher Db reading.

llcoolpass

ok , and the measurements you got, they were on asphault highway like mine, with stock wheel/tire size/speed rating/tire pres and decent tires [i got dunlop sp sport]?

also, armrest not best spot to measure, i would think. also, u got link to this thread you speak of where people are interested in this stuff?

update: car and driver C/D C&D 1992 cars under 30K [on this forum somewhere]
the lexus es 300 whoops all the cars it was compared to in sound measurement dept:
in fact these numbers are considered good even in today's luxury cars, incredibly good in 1992:
[A weight as well]
idle, 38 dB
full throttle, 71 dB
70 mph cruise, 67 dB
70 mph coast, 67 dB
[meaning: no addition to noise level by engine! mine is not this way, at least in its current condition/form]

tuan92129

This was taken on a 6 year-old concrete highway last year, when i still had the is300 rims w/ 45 series tires which did add a lot of noise.
I will probably retake the measurements in another two weeks when i have more time.
The measurements were taken after i added sound insulation to the door panels, rear seat, and partially on the trunk bottom, the other thread is titled "es300 sound deadening"

i also noticed that turning the fan from low to off took off a decibel of noise, if anyone was interested in how much noise that made

llcoolpass

concrete , no way you got those measurement. but i await your retest with stock tires on asphault [BLACK] highway ;-)

tuan92129

State route 56, CA was completed 2003/4 so its pretty smooth...all the highways in my area are concrete, so i'd probably have to test on a surface street.
Before i had BF Goodrich 215 45 R17 g-sport
Now, I have Cooper CS4 touring size 205 65 R15 (very smooth riding)
Non other than people like you and me ;p
https://www.clublexus.com/forums/es3...ing-diy-3.html

tuan92129

Concrete Highway:
55 mph 65db
60 mph 66 db
65 mph 66.5db
70 mph 67,68,67,68 (avg: 67.5)
75 mph 68.5
80 mph 70 db

Asphalt:
40 mph: 60db
50 mph 62db

Meter Used: Radio shack analog sound meter (digital ones not in stock)
Meter was held in one hand at ear level with the microphone pointing upwards (its supposed to be held horizontally, but i was driving by myself and there was no one else to read the meter)
Idle: <50 db (meter cannot read below 50 db)