# Setting Crossover points - What to listen to.



## mvw2 (Oct 2, 2005)

Well I just swapped out my hardware crossover and started toying with my 2 way set in an active setup. I'm having a hard time deciding how I should go about setting the crossover points.

A little background data:
System:
-Subaru Forester
-Running front 2-way only, in the stock door locations(at the moment)
-JVC KD-AR8500 HU
-Phoenix Gold Ti Elite 6.5" woofers
-Morel TW-1 tweeters
-Swapped out PG's crossover to try active througbh the HU
-Cadence Z4000 amp (75W x 4)

Speaker info:
Morel TW-1 tweeters:
-Frequency response 2000-22000 Hz
-Fs 1100 Hz
http://www.morelhifi.com/support/pdf/mobile/pulse-tw1.pdf

Phoenix Gold Ti 6 drivers:
-Frequency response: ?
-Fs: 62.18 Hz
ftp://208.187.38.55/Phoenix_Gold/Manuals/Speakers/TitaniumElite/TiEliteComponentsManual.pdf

HU crossover options:
-Tweeter HPF: 1.6 - 16 kHz 
-Mid LPF: 1.6 - 16 kHz 
-Mid HPF: 31.5 - ?(didn't try how high, say up to 1kHz or so, running at 40 - 50 Hz)
-Sub LPF: (haven't played with it yet, no sub in yet)
-Slopes of -6/-12/-18 dB/octave available for all

Stock passive crossovers:
-Morel Pulse crossover(running TW-1 tweeters): 3800 Hz at -6 dB/octave slope
-PG Ti Elite crossover: 3000 Hz at -24 dB/octave slope


Now there seems to be almost no real data other than the tech manuals that indicate any usable frequency ranges for these speakers. I know each speaker has its normal operating frequency range. Trying to play above or below this "normal" range would introduce unwanted distortion and strain on the speaker. One can't expect a tweeter to play 20 Hz with authority or a 6.5" woofer 10 kHz cleanly.

Playing with the speakers I have, seperately, it's tough to tell where I should cross over each speaker. My mid seems to play up to 16 kHz quite happily, but begins to drop off around 5 kHz with dimishing gain on up. Running my tweeter down at 1.6 kHz with a -6 dB/octave slope shows that the tweeter seems ok running down quite low. If I were to play either speaker alone, I'd run them at their full capability, the mid all the way up and the tweeter as low as I can set.

However, when I combine the speakers together, I find myself having a tough time deciding what I should do. I have a few options.

First, I can set the crossover point quite low. I set the mid to 1.6 kHz with a -18 slope and the tweeter at 2 or 2.5 kHz with an -18 or -12 slope, respectively, and this seems to sound ok. The mids have a lively brightness to them if I run them at anything 2 kHz or higher, and the tweeters have a tough time blending.

Second, I can set the crossover quite high. I set the mids to say 4 or 5 kHz and the tweeters at 5 or 6.3 kHz at whatever slope(I think -12 for both worked well). This creates a lively presence with the mids as well as a stronger high mid presence(mids have more umph behind them than the tweeters). It's also the only way for the high mids to blend well, either let the tweeter do everything or the woofer everything. Then the tweeter just does it's little high frequency work to attenuate the top range that the woofer can't strongly produce. This seems to work ok as well, but I'm not sure if I should be having the woofer play so much of the upper range.

Third, I can overlap both speakers through a frequency range. I ran run the tweeter down to 1.6 kHz and the woofer up to 5 kHz and let them both run that middle range. Despite this working, it tends to create an odd muddling of sound due to two sources playing the same music. I can boost certain frequencies this way, but it seems more...messy.

One additional thing I can do is control how loud the woofer and tweeter is in respect to each other. Per the HU's crossover design, the front preouts are used for the tweeters and the rear preouts are used for the mids(I also have a seperate sub preout). With this setup, I can use the fade adjustment to control the volume ratio between the woofer and tweeter. This too has a big impact on the sound. You can overpower one speaker or the other and also use it to help blend/match the volume of the frequencies around the crossover point. A general overall effect it has is kind of similar to a tone adjustment. I run the fade rear and the overall presence warms and gets more bassy. I run the fade forward and tone brightens. It's kind of interesting and allows me some additional tuning.

In the end, I'm not really sure how to go about setting the whole thing up. I can go by ear and deside that I like a certain setup, but I'm not sure if I'm actually running over or under the "normal" ranges of the speakers.

I guess my biggest inquiry is what exactly should I be listening for? Are there any techniques in desiding which frequency is the best? How far should I gap or perhaps overlap the crossover points? Should I listen to the tweeters and woofers seperately or always mixed together? I guess I'm basically looking for tricks, little details/sounds/behaviors I should be listening for that tell me I'm playing too high or too low a freqency or that I'm overlapped too much or not overlapped enough? I guess the overlaping or lack there of is pretty easy to hear. However, running the correct points and slopes is a bit harder. I know the ear tells a lot. Still, I'd hate to be at a point where I think I'm good and don't realize I'm way off where I should be or completely avoiding a much better/proper setting.

I guess as a final note, I decided to go away from the passive crossover to seek some more tunability, to get a little more power into my own hands. There are some oddities that I don't like about my current setup. A good part of it is poor level of my current installation(stock door locations, no sound deadening, not much for proper aiming). That will be fixed come warmer weather as I plan to do full deadening and do a little custom fabrication for some more proper aiming. Something more recent will be me raising the tweeters up to the a-pillars rather than in the doors by the woofer as they are now. I also, find that with the passive crossover, the woofer and tweeter didn't match well. The woofer has a brightness to it and a strong upper mid frequency presence(2-3 kHz). The tweeter is quite laid back and almost too quiet for the woofer, both overall and somewhat lacking in the lower high frequency range(3 - 8 kHz) when paired to the woofer. I'm considering another tweeter option, but I'll work with these for now. The active setup allows me to fix a few flaws. I can boost the overall tweeter presence in relation to the woofers. I can run the upper frequency range of the woofers lower(-6 slope) or cut them off completely(1.6 kHz at -18). I can bring out a little lower presence in the tweeter(running down to 1.6 - 2.5 kHz) to fill in the woofer's previous range.

I kind of have an idea of where I'm going, but I'm not sure if it's best. Right now I'm pretty much running my 1st option as stated above with a quite low crossover point. I'm also running the fade a couple notches forward to boost the tweeters some and create an overall more neutrally toned presence. So far the only flaw I see is that the tweeter just isn't strong enough to create a low high frequency presence with some real authority. Also, I have yet to toy with any EQing. I'm trying to get as close as possible with crossover and fade settings first before I start EQing things out of whack.


Well...

that was a bit long winded.  

Now it's bed time.


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## mtnickel (Mar 15, 2005)

overlap typically isn't a good thing. The speakers are far apart and weird things happen when you play the same freq from speakers at 2 different locations. Phase gets all weird, cancelations, peaks, etc.

1.6k is probably too low for the tweet, and 5k is no doubt much too high for the woofer. Most 6" woofers will play flat (off axis) to around 2k or so, to where the off axis performance drops and the on axis to follow a bit later 3-4k. On axis measurements of a driver arn't really important as in car you never really have drivers directly on axis unless you build kick pods, but usually you aim off axis anyways.

Ok, but to make this short,

A) Try to use higher slopes on the crossovers...most will say, the higher the better, especially when mounting in the mid and tweet in different locations.

B) Aim for a crossover slope a little over double the FS of the tweeter.

You can try 2.5k as a crossover freq. so in terms of slopes of each driver, that'll likely be 2.0k @ 18db on the mid (accoustic 24db most likely off axis), and 3.2k @ 12db on the tweeter. 
If you notice peaks and edgyness/harshness at that approxamate freq (close to the snare drum IIRC...maybe not), then move either one of those outward.

Trust your ears and go with what sounds best, sometimes that may be on very weird settings.

After going with the typical 50hz @ 24db/oct crossover on my sub i am now running 32.5hz @ 6db/oct and loving it. blends much nicer and gives a fuller more even bass.

Good LUCK!


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## mvw2 (Oct 2, 2005)

Oh, I found something else kind of odd. For example, if I play 2 or 3 kHz up on the woofer, it plays up to a certain range of music/instruments. However, if I play down to 2 or 1.6 KHz with the tweeter, the musical range is much different. It doesn't seem to output as low of info as one would assume. For example, at 1.6 kHz, I expect musical output of guitars and vocals. But, at that point, at least with a steep slope, I'm still only getting the very high end spectrum of the musical range, cymbals and such. This seems odd. Maybe it's normal. I'm not sure. If I run a lower slope, say -6, I get a far greater musical range. There's a tone more lower toned info that way, but it stays reguardless if I cross at 2, 2.5, and even 3.2 kHz. The low slope seems to allow a lot full range of info. On the contrary, with a steep slope, say -18, I get a sharp cutoff and primarily only the very high end spectrum, even when crossed down at 1.6 kHz. It seems odd... Of course, I don't listen to many tweeters by themselves, so I'm not sure.

For my current settings. I've tried the woofer at 1.6 and 2 kHz, and those seem to be my two best options. I prefer 1.6 kHz, but it seems to leave a slight gap between the woofer and tweeter, almost forcing me to stretch the tweeter down too far and overlap or at least fade forward to diminish the woofer's output. At 2 kHz, I start to introduces the woofer's brightness. The strong high range presence is wonderful if I let the woofer play a much larger area, say up to 5 - 6.3 kHz, since it will all blend together well. However, just chopping it at 2 kHz leaves a point that requires a tweeter capable of picking up at 2 kHz with some authority. Mine doesn't exactly do that. It may be something I just have to EQ down to get a decent blend. I know the tweeter is nowhere capable of matching the high end presence of the woofer. Even with the passive crossover at 3 kHz, I found myself boosting the 4-8 kHz range a bit to create a strong enough high end presence to match what the woofer was putting out. It all seems to point to the tweeters, a feeling I've had for some time.

For the tweeter, I just run as low as needed to eliminate the void sound you get when you have the crossover points too far appart. If I run too low, I can tell the overlapping. I've tried -12 and -6 slopes, but I'm not really sure if I like it that shallow. That just gives a great chance for overlapping unless you cross a lot higher. It's something I haven't played with a whole lot. It just always seemed the steeper slope sounded better. I'll fiddle with a shallower slope on the tweeter and see if I can find a decent setting I like. At the moment, the woofer and tweeter are only about an inch appart, so the overlap doesn't get real goofy, but you can still tell two sources are playing the same thing. I'm planning to move the tweeters up and toying with them high and away from the woofer soon, today maybe. With such laid back tweeters, I'm hoping it will help some that I get them up and out in the open.


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## ArcL100 (Jun 17, 2005)

Heh, you and I have similar ears it would seem. I'm simply going to reaffirm some of your beliefs - you're basically right on point. I believe it was codt or some other member preferred running the tweeters as low as possible, while I prefer going as high as possible with my mid as I much prefer a woofer playing midrange to a tweeter playing the same range - for the same reasons you mentioned (the woofer sounds more full).

I gradually upped my low pass on my Dayton RS225 8" mids until there was audible cone breakup - most noticable on vocals ("Sss" became "Chhh") - then backed down a setting or two.

For matching tweets to mids, I again, have had the same results as you have. When the mid LP and tweet HP get anywhere near each other, the slightest overlap begins to reduce the clarity in the midrange and everything sounds more like the original oem speakers. A sizeable gap (I run a ~1.5k LP and ~2.5k HP) really brings out the crispness in instruments and vocals, especially on good recordings, as well as raises my soundstage in my particular install, YRMV. However, as you've noticed, too large of a gap can cause a miss in mid reproduction.

I have my tweets on the dash, as I preferred this location to near the floor in kick areas. Perhaps you'll have better luck when you try yours up there.

Otherwise, keep at it. Car audio is so crazily dependant on your cabin and speaker placement that really it's just a matter of trial and error and time investment to get everything dialed in, and what works for some or most may have no bearing on your install. IMO you're on the right track though by scrutinizing with your own ears. I'd run the mids as high as possible until they begin to drop-off or breakup, and bring in the tweeters where they leave off and play what tweeters are intended to play - highs.

Good luck 

-aaron


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## Ocelaris (Jun 23, 2005)

If the FS of your tweets are 1100, the minumum you should be crossing over the tweeter is twice that, or 2200hz ~12db/octave So a 2500hz crossover @ 12db is about right... if you crossover the mid at ~2000-2200 @12db is about right, you might have to tone down the mids in that range though...

Anything as large as a 6" is probably going to start distorting when you get up that high... plus as arc said, overlap is rarely a good thing...


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## mvw2 (Oct 2, 2005)

I've been playing with it some and moved my tweeters up as well. I have my tweeters just velcroed the door's sail panes right now. It's a convenient spot and allows a flush mount option with little problems. However, they're about 6" closer to the ear than the woofer. Right now, I'm just adjusting with time alignment. However, I may try to stick them up farther on the a-pillars, pretty much all the way up the window corner. This would provide basically equal length between my woofer and tweeter and no require time alignment at all. TA may work well enough for me to not fuss, but I haven't desided. Having them out in the open helps sound quite a bit. High end detail is far more present, and they sound a bit fuller, not getting lost down in the door. 

I'm still at a toss up between running my mids high or my tweeters low. I kind of prefer my tweeters running low as I produce a fuller effect up high. I currently have my woofers crossed at 1.6 kHz at a -18 slope and my tweeters crossed at 2 kHz also with a -18 slope. This seems to work out pretty well, and the sound feels full. With my fade 3 or 4 rear, they blend well with the woofer and neither feel overpowering. Despite my toying, I keep on coming back to this setup. 

If I run the woofers high, I can gain a brightness, well more of a liveliness to the music. These woofers have kind of a "live concert" kind of brightness to them from basically 2 kHz on up. It's fine if I play full range out of them and everything blends. However, it makes quite a hassle when I chop it off somewhere and hope that the tweeter can match. I can get an option that seems to work ok. I run the woofers up to 4 kHz and the tweeter at 5 or 6.3 kHz with a gentle -6 slope. When I run it that high, I always seem to want a shallower slope... One current problem with this version is that my woofers are still in a stock and relatively poorly aimed orientation in a door with no sound deadening. It leads to less than stellar audio. If only for this reason, I see running a large portion of the audio spectrum through the woofers. I may look into this option after I get the doors properly deadened and the woofers aimed in a decent fashon. The only other current note is that I'm trying to raise the sound stage. Bringing more attention to the woofers isn't exactly the best route.

In the end, I generally revert back to the first setup. I'm not finding much of a problem with it so far, so I may stick with it for now.


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## cotdt (Oct 3, 2005)

Listen to the crossover region.


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## mvw2 (Oct 2, 2005)

I need to find some good songs to test the crossover point(s) or make some test tones for it.


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## Ocelaris (Jun 23, 2005)

Try to keep the tweeters as close to the woofer as possible... the farther you go from them, the more you are going to get a distorted "sound stage"

Try playing your tweeters by themselves, do you really thingk 2khz sounds good? Try it at 2khz, then 2.2khz, then 2.5khz... same with your woofers.

The smartest people I know subtract from their eq and gain settings, and I am still developing my ear. The most important thing, is to play music that you know by heart, and can differentiate. Because nobody can listen to tones and say "yeah that sounds tinny" the world works only on familiarity. remember no one can tell you what sounds good, only your ears know. With that in mind, feel free to disregard my reccomended x-over points, but the #s usually don't lie... 2x FS = low pass crossover point minimum.


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## mvw2 (Oct 2, 2005)

I've been toying some more. The more I play with the settings, the more of an odd pair it seems these two speakers are. Still, I'm trying to find a happy union. 

I've been stuck at crossing over the woofer at 1.6kHz as to keep its inherent liveliness at bay. At 1.6kHz and lower, this woofer is very laid back and passive. It's just kind of there.

I tried to work with this using my tweeter and running as low as I could, trying 2.5kHz, 2kHz, and even 1.6kHz and fiddling with my fade to balance the two together. I generally found the tweeter to be overpowering in the lower range, requiring heavy fading to the woofers to get something that would _seem_ blended. It worked ok, but it really needed something different around the 2kHz mark, never seemed quite right.

I tried crossing very high, up at 4, 5, 6kHz even to kind of just let the woofer shine and just use the tweeter as the top end sparkle. This actually kind of worked ok, but it wasn't the presence I was going for. I always kept going back to a low crossover point.

So far, I'm working on a compromize. I'm running the woofer at 2kHz with a -18 slope. This adds that missing presence around 2kHz that the tweeter can't provide. However, the liveliness of the woofer begins to show through. This creates a challenge.

So far, I've been trying steep slopes with the tweeter, generally always -18 and maybe -12 if I was crossing the tweeter a couple notches higher. The steep slope and resulting sharp frequency cutoff on the tweeter never seemed natural, always making me want to cross lower to get a fuller feel. I tried a shallower slope before, -12 and -6, mostly when toying with the really high crossover points, 5, 6, 8kHz, since I was able to get a little fuller feel out of the tweeter when crossed way up high. At lower frequencies, the overlap just seemed too noticable, and with the woofer at 1.6kHz, never seemed to work out well.

With the woofer crossed at 2kHz however, I get a whole different presence characteristic around the crossover point. I adjusting the tweeter, tried -18 and didn't find happiness. I tried -12 and found 2.5kHz to work pretty well. I went to a -6 slope and pushed higher, now at 3.2kHz. Hmm, seems pretty nice. The woofer gives that hint of livelyness and filling the area that the tweeter can not, and the tweeter stays up high and content while being allowed to extend down lower for a fuller sounding presence. I played with the fade a little, now only rearward 1 notch. Man, this is sounding nice. I played a few songs. I notched the fade back one more to bring out the woofer more. Now things are sounding great.

So far, I've left it at that for this evening. I'll run through quite a few more songs and give it a listening to with a fresh pair of ears in the morning...see if I'm still liking it. I'll know if it's good when I can hop in the car for several days straight without wanting to tweak it again, lol. So far, this mismatched pair is sounding pretty sexy.

Now the only flaws that are really showing out is a bit of boominess/distortion from my lovely undeadened doors and the less than idea stock aiming for the woofer's contribution to the sound stage. I've been thinking about doing some custom fiberglass work on the doors to get some good aiming on the speakers and the deadening will all come when the weather warms up.

It's interesting to note that despite having the woofers and tweeter well seperated from each other, the overall presence isn't that bad with the help of some time alignment. Sound stage seems to be poking through with the tweeters, but the mids aren't helping it in their current configuration. The seperation along doesn't seem to be that big of an issue using some minor TA. I know running the woofers and tweeter together makes things easy. My bro first ran his tweeters and woofers seperate, and he never really liked the sound. He now has them together and is liking them a lot better. Of course, this is a different car, different speakers, and no available TA, although distances weren't that bad.


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## ArcL100 (Jun 17, 2005)

Lol, good work. I find the 2 hour trips from home to school help me establish whether or not I made a good or bad adjustment 

-aaron


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## mvw2 (Oct 2, 2005)

Yeah, I've got a couple trips to town to make tomorrow...er today. That should give me a couple hours to try my current setup on.

I'm still not sure if it was worth giving up 300w rms using PG's crossover and my amped bridged. Down to 75 watts is a big sacrifice for a little tunability. I know I will no longer be able to use brute force to push out the bottom end on my woofers. 75's good, but it was kinda nice to be at the point where you know your limit is the physical capability of the driver. 75 watts is good for 90% of my normal listening levels. I should probably redo my gains first though before I really say anything. At 300w, I was adjusting mainly for driver distortion rather than clipping.

I kind of wish PG's crossover was more tunable. All it had was a -2dB adjustment for the tweeters...that's it. On the plus side, it looks dead sexy, but ears don't care much for looks. I don't think I could have been happy with it in the door location, and full adjustability is nice to have.


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## mvw2 (Oct 2, 2005)

Well, I ran to town and back to get some motor oil and a filter for my oil change. In the mean time, I started playing with the EQ settings to see what kind of curve I'd end up with at the current setup. I ran through some random songs adjusting EQ as flat as I could get it(no area overpowering or lacking in presence). My EQ is a basic 9-band EQ: 63, 125, 250, 500, 1k, 2k, 4k, 8k, 12.5k, or I could use an adjustable 3 band parametric. The graphic varaint is just easier to play with quickly as you can zip back and forth and adjust everything quickly.

I came to a pleasant EQ solution. Basically, it was flat through the tweeter range, a one step drop at the crossover point(could fade forward to the tweeters one, but that's a more pronounced jump than one step on the EQ). In fact, the only attenuation I have is a good bit of a boost at 500Hz(not sure why exactly but always has been lacking), then back down flat at 250Hz, and then a good bit of attenuation at 125 and 63Hz settings, but that's probably a greater factor of having an undeadened door than anything else(possibly the cause of 500Hz cancelation too?). Otherwise, in the end, everything was pretty much flat through and through. It sounds good, it EQs good, and I think I've found a happy point with my setup.


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