Audioque HD3 owners. . . tuning question

[dleccord 5,000+ posts]

3/4s of 70 is 53

 

[Jeremiah25 10+ year member]

Peak was taken at the headrest also.

I just noticed that you were taking headrest measurements. This could be the reason why you are peaking at those frequencies. Try sticking the sensor to the windshield in the dB Drag position and see if the peak frequency changes. I'm almost positive that it will go up at least 4-5 hz.

 

[Phreaker 10+ year member]

Yeah but a$$ backwards..

My hu doesn't go from 0 (being lowest volume) to 70 (being highest possible volume)

It works like this....70 (lowest volume) to 0 (loudest highest possible volume)

So yes if my HU worked 0-70 the yes 52 would be 3/4's volume but since they work on an a$$ backwards deal 18 is 3/4's

.....70 / 4 = 17.5

17.5 x 3 = 52.5 (we'll say 52)

70 - 52 = 18

 

[Jeremiah25 10+ year member]

Yeah but a$$ backwards..
My hu doesn't go from 0 (being lowest volume) to 70 (being highest possible volume)

It works like this....70 (lowest volume) to 0 (loudest highest possible volume)

So yes if my HU worked 0-70 the yes 52 would be 3/4's volume but since they work on an a$$ backwards deal 18 is 3/4's

.....70 / 4 = 17.5

17.5 x 3 = 52.5 (we'll say 52)

70 - 52 = 18

WTF kindof ghetto headunit is it? The sony in you sig? I have never seen one like that.

 

[prochobo 10+ year member]

I just noticed that you were taking headrest measurements. This could be the reason why you are peaking at those frequencies. Try sticking the sensor to the windshield in the dB Drag position and see if the peak frequency changes. I'm almost positive that it will go up at least 4-5 hz.

I'm also sure that it will go up a little also. However, with my other setup, it peaked right above tuning frequency. Also, other Accord owners are reporting around a 50hz peak at the headrest. I know that those measurements are equipment/install specific, but it's vehicle specific as well which has me stumped.

 

[dleccord 5,000+ posts]

plz find a peak note of the vehicle at the dash, if you have time. we have the same cars. so far my highest db has been reached through boxes tuned 40-43hz, where i peak around 50hz also.

 

[Phreaker 10+ year member]

WTF kindof ghetto headunit is it? The sony in you sig? I have never seen one like that.

Yup...

To the original thread starter....sorry for thread jacking.

 

[Jeremiah25 10+ year member]

I'm also sure that it will go up a little also. However, with my other setup, it peaked right above tuning frequency. Also, other Accord owners are reporting around a 50hz peak at the headrest. I know that those measurements are equipment/install specific, but it's vehicle specific as well which has me stumped.

Well, this is my theory, from what you have stated so far:

You have stated that the score peaks at 45hz with both 50hz and 48hz tuning, with the sensor placed at the headrest of the car, and that the frequency that the score peaks at drops lower as you tune lower. From my experience, as you start tuning higher the peak score inside the car will often stay at the same frequency, but if you tune lower the peak score inside the car will drop to lower frequencies. For example, in my explorer I can change the tuning from 39hz all the way up to around 60hz, and the score will still peak at 49hz legal, but I can lower the tuning down to around 35 hz and the frequency where it hits it's peak score will drop down to around 45hz legal. I believe you are seeing your natural car peak frequency at around 45hz with the sensor placed at the head rest. I also believe that you will see a natural peak score at around 50hz with the sensor stuck to the windshield, if you test it. I think you will find that if you start cutting the ports in small increments and testing alot, that your peak frequency is going to want to stay at around 45hz at the headrest, and that you will find a fairly large range of tuning frequencies that it will still result in that peak frequency.

I think the tuning frequency that WINISD is reporting in this situation may be off a few hz, but I doubt that it is a dramatic difference. I have often found by running an impedance sweep than the WINISD figures are off a little, but not much usually.

My best advice is to play with the tuning frequency in the car until you find the results that you are looking for. Use the WINISD tuning results as a reference, and keep good notes. That way if you want to change the setup around in the future, your notes and reference tuning may help you save some time testing.