Does temperature affect tuning?

[naiku]

I heard some competitors were complaining at a comp (might have been finals) because it was held in a dome that used air pressure to keep the structure rigid. The added air pressure was causing their comp tunes to sound odd.

I remember when I went to SVR last year a lot of people were noticing the effect of it being held in an air conditioned dome and trying to tweak the tune as it did not sound the same as when outside.

[Queef]

Time alignment might be affected . . .

Your testing instruments might show it , but I wouldn't worry about it enough to check the barometer before I retuned my vehicle ?

[blockrocker]

Time alignment might be affected . . .

Your testing instruments might show it , but I wouldn't worry about it enough to check the barometer before I retuned my vehicle ?

I would tend to agree with this too. I think I read in the Audiofrog tuning guide that Ta isn't critical to fractions of an inch. In fact they had shown in graphs that TA could be off up to a few inches and not really affect the overall sound quality. So if an inch or two doesn't dilute the quality, than I would think that normal changes in temperature, humidity etc, should be minimal as well.

https://testgear.audiofrog.com/wp-co...y-it-Works.pdf

This is the guide I was talking about. I believe its in the first half of the book, somewhere between pages 10-30. Tonnes of great info in this baby!

EDIT: Again I am still learning this stuff too, so I may have misinterpreted it a little. If someone with more experience can weigh in it would be great.
Phase and TA are still my biggest challenges to understand.

[SkizeR]

It definitely makes a difference. Idk how or why, but ive noticed tunes go to shit in the winter.

[JCsAudio]

I noticed this a long time ago mostly with my sub stage. When the temperature dips below 15 degrees my subwoofer gets quiet. A few mornings when the temperature was about 0 I didn’t hear my subwoofer at all for the first 15 minutes of the ride. I started a thread called Cold Bass for those that might remember. I haven’t noticed it this year though as bad and it was 8 degrees out this morning but I have also been letting the truck warm up for 10-15 minutes before I drive away. Anything mechanical with tight tolerances and moves back and forth is going to Be affected by temperature.

[Smitty]

Living in FL I've only noticed this a couple of times ever. I just assumed it was due to the drivers being cold and stiff. Never really considered it being about air temp, humidity, or pressure. This is an interesting topic.

[Hillbilly SQ]

To elaborate on my first post in this thread-I tend to start my tune over from scratch 1-2 times a year just because. Speaker parameters can change with age and the install in general can and will change with age as things deteriorate and shift. If you notice your system isn't sounding as tight as it once was after months without touching it you probably aren't crazy. In my Grand Cherokee with Frog gs690 and gb10 front I did a retune because the original tune went to shit for some reason. Everyone loved the original tune when it was fresh but something went terribly wrong over time. I think part of it was from speakers being tight out of the box when the tune was done and they changed enough over time to splatter a different response. Also the closed cell foam ring between the speaker and door card could have changed how they were sealing off the "tunnel". The cabin of a car is a harsh environment. It's my opinion that all speakers mounted in dash and doors are on borrowed time while home speakers can literally last decades without showing too much age minus the need to freshen up crossover caps every 10-20 years.

[Holmz]

At 68 °F, the speed of sound in air is about 1,125 ft/s. Temperature, humidity, and pressure definitely affect the sound. I heard some competitors were complaining at a comp (might have been finals) because it was held in a dome that used air pressure to keep the structure rigid. The added air pressure was causing their comp tunes to sound odd. One guy did an RTA sweep earlier in the day, and another later in the evening...you could see a definite change in response.

Also, as Chris was saying, speakers are stiffer when cold.

^Yeah^
But was it the air pressure or the air temp?

The speed of sound is proportional the the temp.
20C is 291.15 kelvin (68F) so 32F and 100F swing the velocity by a handful of %

(I am not sure about humidity??, nor pressure)
But I found it: https://physics.stackexchange.com/qu...o-air-pressure

One could consider the DSP sort of like an ECU, where temp, pressure and humidity sensors all are read.
In the case of an engine then the air density is computed.

In a DSP it would be the speed'of sound that then would convert distance into delay.
However most cars have the AC somewhere between 68F and 86F (20-30C)... so I would just tune it warm.

[Queef]

It ( probably ) was the pressurizing done to keep structure stiff. In restautants , we had to balance air so that doors could be used ( negative air pressure = pulling really hard to open )(positive pressure = door opens easy [ too much and air conditioning goes out front/ rear / or other opening ].
Ideally , when pressurizing air some moisture is removed and needs to be drained/bled off , from time-to-time.

[JCsAudio]

The resonance of the doors and panels of the car also change with temperature and that has to have some affect on sound even with sound deadening.