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Discussion Starter #1
So, I've had the car about almost 2 years now and never loved the stereo. Probably 8 years ago i worked at a shop during college for a few years and had full active Hertz Mille system and loved it. Got a new car and quit doing audio stuff and was okay with the bose system. The Stinger has the upgraded Harmon Kardon system with 3 way fronts, 2-way rear, center, and subs under the front seat. I also added a ported 8 to the rear. My problem is that i am not a bright/harsh treble fan. I have been operating with the EQ at -9 of (+/-10) and it still sounds harsh. The setup is a 6.5" 2-ohm woofer, 2.5" 2-ohm mid, and 1" 4-ohm tweeter.







So i started investigating the other day into swapping out tweeters to something more forgiving, but i started by putting a piece of felt between the tweeter and grill. This helped a good bit in bringing the tweeter down, but i kept digging around doing some measurements. I grabbed one of my PC speakers which are not perfect, but sound pretty good. I used my ipad pro to grab a few measurements, which is no means calibrated, but it gives me an idea of what is going on. Some of these may not be aligned in amplitude, just as an example.

It seems the factory system is adding a ton of treble. Same sweep compared on same speaker in similar ways. Car EQ is at 0. This could be because the tweeter is 4ohm and mid is 2ohm, so when they both play its about even. Not sure.


Same external speaker on Mid and then on tweeter output. Identical signal. What i see here is that the mid and tweeter is a high pass filter only, and no low pass in sight. High pass is at ~500hz.


Factory speaker mid vs tweeter. Is this a problem to have both the mid and tweeter playing the same frequencies? Is there or reason they didnt make the mid a bandpass?


This is the factory tweeter and mid, with the felt and EQ adjustments. It is much better sounding to my ears, but still not perfect.


My questions:
1. Would swapping the tweeter to something like a XT25 or some other relaxed tweeter get me closer to where i want to be or is the factory system screwing the EQ up too much. This was my original plan before looking into it more.
2. Should there be a lowpass filter on the mid? Could this be contributing to the behavior i don't enjoy with the mid and tweeter playing high frequencies together? I could add a small diy filter to the door, but not sure what else to consider in regards to polarity or phase or anything.
3. The tweeter has a single 4.7 micro farad cap attached. Based on my calc, this is a 8.4 kHz 6dB high pass filter, but that is not what the graph shows. Did i calculate this wrong?Or is it right and they are boosting 3kHz a ton to get the peak there?
4. Is the only fix to go active? Would this affect the factory time alignment if only going active on the front door speakers? I don't really want to do this as its a rabbit hole.


Let me know if I can answer any other questions.

Thanks
 

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Factory speaker setups with a tweeter almost always let the woofer natural inductance roll off the top end, like lots of cheap bookshelf speakers.

It is a cost savings matter, nothing else.

A simple inductor would probably do wonders, a steeper passive crossover even better.

I would be curious how losing the tweeter entirely with a better full range would sound in the door. High in the door card often works well for a tweeter location, so it makes sense that a full range might work well. That midrange looks horrible up high though.
 

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Discussion Starter #3 (Edited)
if I was to change the tweeter and build a simple 6dB or 12dB filter for the mid and tweeter, what frequency would be a good start? Like I said, the factory tweeter has a 4.7 microfarad capacitor in line which calculates to 8.4kHZ, but that doesn’t seem right looking at the frequency chart. I have never really messed with a 6dB filter, so not sure where to place it to be safe for the tweeter. How about phase, adding a filter changes the phase of the driver, so would I need to change anything here? I’m leaning toward just using a 4.7uFD like the factory has on the tweeter, and adding a simple inductor to the woofer. Would this be at the same 8.4kHz? That just seems so high.

I would swap the mid, but I have not found any 2-2.5” mids that are 2 ohm, and I don’t want to take a hit going to a 4 ohm yet. The door 6.5” woofer is crossed over around 500hz.
 

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Disconnect tweeter and see how it sounds without it. See if the mid's provide enough highs for your ears with normal "treble" adjustments as needed. If not happy tweeterless, then find a smoother sounding tweeter.... maybe 6 or 8 ohms which would help possible attenuate the ear bleeding. I prefer softer and silk domes and don't care for hard or metallic tweeters. Can you tell the material type of tweeter in that vehicle?

You're not the only one, with eardrums, that complains about the OE highs on some of JBL/Harman/Infiniti systems.
Don't assume the impedance across the operating range matches the 'ink' label on the midrange or tweeter. This is why passive crossover building isn't as simple as the DIY books state.

Use a calculator, try solen split instead of butterworth, and use some quality coils/caps(parts express should be good enough).

I can't make out the frequency in your graphs. But, being a 1st order 6db passive crossover, I would probably want that tweeter cut off pretty highway in that 8-10khz range too.

Hears(pun intended) the calculator, pick a frequency, and build away(prefer solen over buttery)

Sites-HK-US-Site looks like a ~1" tweeter
How are those factory 25mm tweeters mounted in the door card? easy swap?

And, will you have to repeat the same mods for the back doors?

Bandpass the higher freqs on the midranges with(or equivalent from amazon/ebay/madisound/solen) :

Highpass the mid freq's on the tweeters with(or test above coils with stock capacitors 1st):

Makes it simple since the 'active' crossover only feed 500hz+ to those mid+tweet. And, if you plan on using the OE bass blocker with the tweeter, all you need is a couple of the inductor coils. Mount them as close to the speaker or on the speaker frame/basket/door card.
 

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Try a good set of silk dome tweeters to take some edge off. OEM tweeters are known to be harsh plastic pieces of sh....

Ge0
 

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Discussion Starter #6
I figured the factory tweeter was a metal dome like the HK in the bmw, but it’s a 1” soft dome. I’m leaning toward a Peerless XT25sc90 and the same 4.7uF cap initially to see how that fares. I should be able to pretty easily mount it in the same spot. The tweeter pods are angled a bit toward the listener. It may be good enough for me the time, because I’m not looking for perfect audio, I just want it to be pleasant to listen to.

275461

275462
 

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Yeah. That tweet ain't nowhere near as cheap as the Bose P.O.S. that came out of my Porsche. I still think tweeter replacement is the route to go. I know the guys at Harman. They do everything for a specific reason. But, in the end they are looking to please the 99%. Not us 1% who are critical of our sound.

Ge0
 

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the graph you posted of the mid looks like it might be the asshole here. i would throw a coil in line just to see how it sounds. then move on. it would be a shame to change tweeters and have the same or maybe worse of a problem.
 

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Mid is 2-ohm 500hz-20000
Tweeter is 4-ohm 8400hz-20000

Does this mean that the parallel load from 8.4k-20k is 1.3333ohms? Either get an 8ohm tweeter, or choke/bandpass the mid with a coil, or trade the car in.
 

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Discussion Starter #10
Mid is 2-ohm 500hz-20000
Tweeter is 4-ohm 8400hz-20000

Does this mean that the parallel load from 8.4k-20k is 1.3333ohms? Either get an 8ohm tweeter, or choke/bandpass the mid with a coil, or trade the car in.
It’s an active setup, so no weird parallel values.

I ordered the Peerless XT25SC90 tweeter, and a few caps and inductors to play around with 1st order filters on both the mid and tweeter. If this doesn’t work, I plan on going active with a small 4ch and basic Dsp on the mid and tweeter.
 

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You stated that the tweeter had a capacitor

Did you test the midrange output with the tweeter disconnected? tweeter output with midrange disconnect? compared to both running?

Partially active and overly eq'd? not much different from most Harman/JBL/Infinity used by various automakers.
 
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