'Aeroplane' sound during amp installation

[DanPromote]

I was transferring my old audio equipment from my previous car to the current one. All installation was done by an audio shop & they consist of 1 set of 6.5in component speakers, 1 x 5.1/4 in speakers, 1 12in sub and 2 x 2 way amp. However, after all was done I get this annoying 'Aeroplane' sound when I step on the accelerator. This never happened on my Proton.The installer said that BMWs are particularly prone to 'Aeroplane' sound and only high end amps will solve this problem. Is this just sales talk or is this a fact? Is there any other way to solve this than spending money on a high end amp? My current components worked like a charm before and I had an Alpine reference series component speakers but unfortunately it was stolen when I sent my car for repairs. Now the front is paired with a 5.25in Clarion 2 way speakers.

 

[saat]

If by "airplane sound" when you step on the accelerator, I assume you mean a background whine coming thru the speakers whose pitch rises and falls with engine RPM. This would indicate that an electrical interference from the alternator or the car's power circuit on the signal side of your system.

Any 2-bit installer should be able to locate the source and fix the problem or put in a capacitor to cure the whine. The capacitor can even be home-made.

Another source of the interference is usually as a result of running the signal cable very near a large electrical source or power cable. As an example, in an E39, the power cable runs from the engine alongside the driver side of the center tunnel to the battery in the back. It is advisable to lay the signal cable the other side of the car or as far away as possible from the power cable. The other alternative is to shield the entire signal circuit.

Of course a faulty equipment e.g. HU or amp may also cause this. This is easily checked by simple elimination.

A BMW is no more notorious as any other car when it comes to electrical interference.

Frankly, in almost all cases, your installer should be able to fix it.

 

[MeanStreak]

Originally posted by saat@Nov 30 2005, 11:35 PM
Another source of the interference is usually as a result of running the signal cable very near a large electrical source or power cable. As an example, in an E39, the power cabler run from the engine alongside the drive side of the center tunnel to the battery in the back. It is advisable to lay the signal cable the other side or as far away as possible from the power cable. The other alternative is to shield the entire signal circuit.

I had the same problem previously with my Honda. As Saat has put it, it was the case of interference. Thus, running the amp's power cable on a on a diff route solved it.

 

[DanPromote]

Yea the Aeroplane sound is the loud whinning sound when the accelerator is pressed.

Looks like the installer doesn't know much about audio installation after all. Although half right, he said it is due to the amp being too close to the car battery (both amps are in the car boot area along with the car battery), but I'm sure this problem can be solved and if one is experienced enough he could have solved it. Instead he said it is due to the amp and buying a high end amp will solve this, I sensed something wrong immediately.

saat, which area is the capasitor installed in? Also what is used to shield the signal circuit?

 

[Vanquish]

Dan,

Let's take one thing at a time. Look at Saat's posting and let's isolate the exact cause before you start buying a cap or an another amp. The level of foundation and technical knowledge among MOST ICE installers in this country is still at a pathetic stage so please don't buy into eveything that they tell you. This could well be due to an incorrect instalation process so go back to him and ask him to look at all possible alternatives ( as above ) and eliminate them one by one. If all else fails .... take your business elsewhere, man!

P/S - I've got 2 amps mounted on an amp rack and it's in the boot too ... as with a lot of other folks here. If the installer got his fundamentals rite at the point of designing and laying out the system, you won't have this problem ... BMW or any other car.

Cheers,

 

[DanPromote]

You got that right imagine where I got it fixed, Brothers in Kelana Jaya! It cost me another RM45 and they confirmed it was due to wiring being put at the wrong place. I took my chances since I was nearby doing some banking but even the notorious Brothers can fix my problem whereas an Audio installer made such fundamental mistakes.

Damn L Two Damansara Perdana, wasted 2 whole days at their shop and came out with crap.

Thanks saat and vanquish for all your advises (teh tarik on me on next tt ), I'm glad I didn't go out and buy unnecessary parts.

 

[saat]

Dan,

Glad to have helped. Advise doesnt cost us anything.

Who says us ice-poisoners are only out to push a victim to get more than what is needed.

cheers

Saat

 

[Vanquish]

Imagine that ...

And to think that we sometimes can be rather hard on those boys at Brother's in general ... Doesn't matter, atleast the problem is sorted out and shame on that installer of yours, Dan. Glad to be of help as always .... no need to buy us a drink as Saat has put it. Enjoy the music now that everything has been fixed ...

Cheers,

 

[manjit]

Finally somebody touch on this...we have the same problem with merc as well...i don't know about others...but i am here to know how to make out that sound...as one of my fren says...that cool man...quite funny but it really sounds cool if itz only a little bit.....Out of topic a little bit...sori

 

[DanPromote]

yea that's the last time I will be visiting the installer in Damansara Perdana, only used to go there coz I was staying nearby and there weren't other shops. I knew something was amiss when he said I must purchase an expensive amp to solve the problem because bmws are prone to 'aeroplane' sound much more than other cars like proton due to the battery position... I just kept quiet and smiled at him.

There was another bmw newbie there driving a black e36 325i auto( he said he got an eclipse player from a member of this forum) but unfortunately he already paid for his set and I coudn't warn him as I found out the solution only the day after. He paid RM1,500 for a 2nd hand amp from the shop.. ouch.. hope it worked better for him than me.

 

[Vanquish]

Originally posted by DanPromote@Dec 6 2005, 11:13 PM

There was another bmw newbie there driving a black e36 325i auto( he said he got an eclipse player from a member of this forum) but unfortunately he already paid for his set and I coudn't warn him as I found out the solution only the day after. He paid RM1,500 for a 2nd hand amp from the shop.. ouch.. hope it worked better for him than me.

Damn ...

Allow me to ask him !!! Hope all went well for him. Err ... that Eclipse unit is from me la !!! Brother, are you reading this ? Ahahahahaha !!! Small world, man !!!

Cheers,

 

[DanPromote]

small world indeed! nice fella hope he has better luck.