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View Full Version : Harsh highs from tweeters at highway speeds



xenofactor07
10-04-2012, 05:31 AM
I've noticed my tweeters seem to sound harsh when I get up to highway speeds. I have Focal IS130s (5 1/4" , mid + tweeter w/ built in cross over.) Because the crossover is built in, there's really no way change the crossover point on the components I don't think. The tweeters are mounted at about chest level on the door, opposite of the side mirror on the interior.

The only way I combat the harshness is by turning the bass up on EQ and turning the treble down. It helps, but I lose the quality of cymbal hits and risk clipping by messing with bass settings.

What's causing this and is there any solution? Perhaps Dynamat?

CAT MAN
10-04-2012, 05:37 AM
wire the tweeters out of phase.

xenofactor07
10-04-2012, 02:01 PM
How does one do that? Do you mean connect one to plus, negative correctly and then connect the other to plus, negative oppositely?

maylar
10-05-2012, 08:13 AM
Yes. The reversed one usually gets softer.

"oppositely".. nice adverb.

mlstrass
10-05-2012, 11:34 AM
wiring out of phase won't change a tweeter, freqs played are too high.

You could try some speaker grill cloth over the tweeter to try and mute it some...

keep_hope_alive
10-05-2012, 01:33 PM
wiring out of phase won't change a tweeter, freqs played are too high.

You could try some speaker grill cloth over the tweeter to try and mute it some...

It certainly can help with the blending of tweeter to mid. Phase is important below 5kHz, where most tweeters play below

CAT MAN
10-05-2012, 03:37 PM
wiring out of phase won't change a tweeter, freqs played are too high.

You could try some speaker grill cloth over the tweeter to try and mute it some...i see someone isnt into sq

nismos14
10-05-2012, 03:51 PM
If they are harsh they will still likely be harsh after phase has been played around with. Now he's saying that his tweeters sound harsh at highway speed. So what are the variables that come into play in that scenario? More than likely the volume has to be increased substantially, so if the tweeters are harsh, you may decide to cut frequencies using the EQ. Increasing the bass doesn't make the high range any less harsh. I would leave the bass where it is on the eq, and lower the higher range eq settings. See how it turns out, but more than likely it will take a lot of testing and tuning. I would also suggest if possible to change the orientation of the tweeters, perhaps angle them such a way that they are not as harsh to the hear without doing many other changes.

mlstrass
10-05-2012, 04:00 PM
It certainly can help with the blending of tweeter to mid. Phase is important below 5kHz, where most tweeters play below

it won't help with his issue and 99% of the time it will make NO diff period....

mlstrass
10-05-2012, 04:02 PM
i see someone isnt into sq

I've dabbled in SQ in the past which is why I know changing phase on tweeters makes no difference. My 880 lets you change on the fly...

nismos14
10-05-2012, 04:13 PM
Flipping the phase has the most pronounced effect when you flip phase on BOTH the tweeters, you can gain a lot more width and breadth, to the ear.

zako
10-06-2012, 01:22 AM
With some speakers, you can't really do much about this. A lot of the time the tweeter harshness comes from the fact that the tweeter is high passed too low. Often, playing 2KHz and up with authority is just too much to ask from a 1 inch diameter tweeter. If you run active you can high pass your tweeters higher and sharper, but this will not work well if your mids can't play upper mid range well. Some supposedly "high end" mids (ID mids, Dayton Reference) are not meant to play above 2KHz for example, pretty much requiring a high end tweeter. By the way, a lot of Focal crossovers come with advanced crossover networks. At very least you should be able to select tweeter attenuation mode (0dB, -3dB, -6dB etc).

My HAT Imagine speakers produced ear piercing upper midrange once the volume is up to make music audible at 70mhp simply because the high pass filter with a 6dB slope in their crossover network was not enough to calm them down. Now I got hold of an active crossover, and the tweeters are set with high pass at 6.3KHz and 12dB slope, and they sound fantastic. The HAT mids do have a reputation for a good upper end extension, so I can still hear upper mid-range without tweeters playing much of it.

What makes tweeters sound bad when they are high passed too low is often the _distortion_. If this is the case, I don't think having them out of phase will help much. Whether in phase or out of phase, distortion is distortion.

Of course, another issue could be that tweeters have low distortion even at high volume, but the crossover does not attenuate them enough. If you can, try to move tweeters far away from your ears, maybe into kick panels if you have them.

There are also the "crossover geek" ways of calming down the tweeters. You can potentially do this by inserting a capacitor or a resistor in-line with the tweeter. A capacitor creates an additional 6dB high pass filter with cut frequency that depends on the cap value. The resistor I believe is for attenuation.

Canaan
10-06-2012, 01:42 AM
OP.
@xenofactor07

Please detail your audio system more clearly.

What head unit are you using? What amp(s)?
Also, what vehicle?

I would like to chime in on my 'fix', but need more info to properly judge the situation.

zako
10-06-2012, 01:44 AM
By the way, some head units have "sound enhancers" and preset EQ curves that usually are just terrible. I remember the "Supreme+" on all new Kenwood head units. The thing is terrible, and adds harshness as high and low frequencies, and based on a third party test reduces stereo separation to 15dB. Try to turn off any of those.

Canaan
10-06-2012, 01:50 AM
By the way, some head units have "sound enhancers" and preset EQ curves that usually are just terrible. I remember the "Supreme+" on all new Kenwood head units. The thing is terrible, and adds harshness as high and low frequencies, and based on a third party test reduces stereo separation to 15dB. Try to turn off any of those.

Also, 'Loudness' control on every Pioneer Hu for at least the last 10yrs boosts the HELL out of bass and treble.
....
...
..
.
can you say "sibilance"

akheathen
10-06-2012, 03:10 AM
running a cap in series with the already existing cap just adds the voltage of the 2 caps together, so they can handle more voltage. however, this means that you could use a slightly smaller cap to increase the cross-over frequency, without ill effect. yes, a resistor will attenuate the db of the tweeter.

keep_hope_alive
10-07-2012, 12:04 AM
it won't help with his issue and 99% of the time it will make NO diff period....

I disagree with you and your made-up statistics. :)

we don't know the rest of the equipment, but if the Focals are powered by a head unit and not an amp, it's likely just head unit amp distortion. he mentions just "bass" and "treble" which is all you get with stock or inexpensive head units.

mlstrass
10-08-2012, 05:30 PM
I disagree with you and your made-up statistics. :)

we don't know the rest of the equipment, but if the Focals are powered by a head unit and not an amp, it's likely just head unit amp distortion. he mentions just "bass" and "treble" which is all you get with stock or inexpensive head units.

my personal experience and what I've also seen stated on DIYMA numerous times about tweeter phase...

keep_hope_alive
10-09-2012, 02:19 AM
Phase interference and comb filtering dominate the challenges we face. Reflections are the biggest challenge as they arrive late and cause constructive and destructive interference.

What is important is not phase at 10kHz, but phase relative to the woofer at and below the crossover point. Figure the wavelength at 2kHz is about 6". This is enough to make phase matter. With a 5kHz crossover point and a wavelength of .225", phase means much less since minute head movements will negate the issue.

One thing to try before adjusting phase or crossover point is to move around. If you hear an issue, move your head a foot and listen.

Diffraction matters, and this is well documented. Tweeter mounting and position relative to other objects is very important. That is why spheres work so well.

I have spent a decent amount of time with a variety of 3-way systems in several orientations, the H701 allows for experimentation from the drivers seat. Tweeter phase is relative to the rest of the system. Can it make a difference? Of course. There are so many complex interactions, every change matters. Does the magnitude of the change vary? Of course. Is it a very easy thing to experiment with? Definitely.