My questions have been answered by Niebur3 and DIYMA but it's always fun to get more opinions on this subject. I knew surprisingly little about crossovers, what slopes where, what an octave is, and basically anything to do with the subject up until a couple weeks ago when I started trying to figure it out.

Since I went active I wanted to experiment with the crossover points and slopes. The Dyn 342 passives use a 6db slope on everything but the tweeter high pass which is 12db. Stock points are 900 and 3500hz.

What I've ended up with is:

Midbass- 70hz@18db/700hz@24db
Mid- 700hz@24db/3,850@24db
Tweeter- 3,850@24

I first used the stock crossover points with a 24db slope as recommended by JBL for the MS8. Lowering the mid from 900 to 700hz sounds like it picked up a good bit of detail. The results were so nice it makes me want to lower the mid high pass some more. I'm guessing that by using the stock crossover points at a 24db slope I might have accidentally killed some of the detail previously.

I'm running the 6 channel JL amp unbridged so it's only 75 watts at 4 ohms. The mid and tweeter are 8 ohms so I doubt I'm pushing more than 40 watts to them.

Here's a copy of a post on DIYMA (this is allowed, right?)

To the OP, you said you had 75w@4ohm which should translate to around 40w@8ohm ; maybe more. Now you driver is good for up to 100w with a 900Hz 6dB/oct slope.
The lowest setting I would use will be 720Hz on a 6dB/oct slope (1/3 octave below) with half the RMS. <-- simple math
From experience, when using a steeper slope, you can go 1/3 octave below for your Xover point:
720Hz 6dB/oct = 570Hz 12dB/oct = 450Hz 18dB = 360Hz 24dB (being the really lowest setting NO CLIPPING INVOLVED)

Now, since you're scared to damage your driver, then choose 450Hz as your lowest setting available.

Kelvin

Now I would never take this mid down this far, just looking for opinions. I know of one guy that's running it 650hz at 12db. I've considered 500hz and to bring the volume up slowly. I'm just curious if I'm going to continue seeing an improvement in SQ or not. I don't want to end up with paperweights and warranty obviously won't cover this type of damage.

Any reason why I shouldn't try and run this mid up to 4khz just for fun?

 

good post and questions.

I am anxious to hear some feedback as I too am not 100% great on setting up an active setup. I am running a 2 way active setup.

currently my crossover points are:

mid - 65hz @ 18db slope > 2k @ 12db slope
tweet - 3.2 @ 24db slope.

I am running Seas w16nx mids and Seas Neo aluminum tweets.

I feel that I am not getting the most out of my setup yet and am looking at adding an additional midbass driver or midrange driver that will fill the void.

 

Are you only using your MS-8 XO's or both amp/MS-8 XO's?

 

This is all so new to me, it's experimentation at this point. I looked up some of the pro audio stuff to get a good idea what frequencies cover what to try and make a semi-educated guess on where to start. But it's still trial and error.

Just the MS8.

 

I too am just using the 3sixty crossover (sorry not trying to thread jack, just curious to learn more as well).

 

That's a good thing. I've read several times that using two crossovers will cause all kinds of weird/bad things.

I'm slowly figuring out the effects of different things. It makes no sense to me but by running the midbass 70hz-700hz vs 900hz, there seems to be a little more midbass snap and the music became more detailed. Crossing the tweeter over higher seemed to bring the stage up higher and they sound clearer.

I've been taking notes of each change for the future because some of my results were not what I expected. I thought I had all of this figured out by reading for hours on the internet but as soon as I started messing around with it, I realized I'm only beginning.

 

I am seriously wanting to go 3 way front. (you are 3 way correct?) if so where do you have your mid range? did you make kicks?

 

This is my first 3 way and I love it. Mids are velcroed to the floor at the firewall until I get my kicks. Niebur3 makes some amazing kicks that take up no floor space. Can't wait to get mine. I would link you to his thread but I'm on my phone.

 

he is making you a set of kicks? wonder if I could twist his arm into making me a set. i have never tackled fiberglassing

 

I'm sure he would. Check out his thread in this section for pictures. I can't remember the title but its one of the only threads by that username. Very nice work and you can barely tell there's a speaker there.

 

Try it..you'll hear the speaker stressing way before u toast it

 

That's the kind of advice I'm looking for. I wasn't sure if there would be any warning.

 

Most drivers can handle twice the power individually than they advertise in the set. I agree that you will have issues before you ruin them.

If that 6 channel is a slash, then it might be doing way more than 40 at 8 ohms - do you have a DC watt meter you can test it with? If it is regular AB, then 40-50w is a pretty safe bet.

 

Its the a6450 so just a regular AB. Still pretty surprised at how loud 40-50w is on the mids. Midbass is only 75watts and it has a good kick. I'm not saying dynamics won't improve with a larger amp but it's surprising just how loud and how good such low wattage sounds. Probably going to end up with an HD900/5 and get rid of the current sub amp.

 

I have a HD 900/5 and absolutely love it so far.

 

Efficient speakers are awesome, huh?

I would strongly suggest that you consider a higher end amp than a slash. You already bought the dyns for major bank, so look around for a higher end amp - even a slightly used one. I never thought that my slash could be beaten so badly until a few days ago.

...so can you change stuff, or is the MS8 "locked" into what it chose?

 

Sure are.

 

i would run that driver even higher considering the physical separation between the 2, I would guess one of them is even out of phase, probably the tweeters. and then spread your slope so the cut-off isn't so sharp, What do the in-phase and out phase white noise test disc's sound like ? are they pin point dead center or sitting on your hood,

 

I also have the 900/5. Very nice amp. If/when you upgrade, I wanna see how it goes. The dyn comps seem very near in the future.

 

Just wanted to let you know that advice worked. I didn't have a mid out of phase, I had a dead channel for the drivers' side mid. So in the end after months of experimenting I've gone with 900/24 and 5000/24 on the mids and its amazing.

 

This might be retarded....but I have a question about this post. When you show the mid x-over points, why is there 2? Wouldn't you only need a single HP point.......sonofabitch I'm stupid and just figured it out. OK so the mid will run above 65hz and below 2K hz. Why wouldn't you HP the tweeter at 2Khz though?

 

Running too low risks the tweeter. Generally the steeper the slope, the lower you can run them, but getting low frequencies on tweets is bad for them. As for the gap, when you have two driver crossing over, they play some of the same frequencies. This will make it louder at the cross over point. A gap allows the two drivers to sum their output to a flatter response curve with no need for EQ.

 

Awesome. Thanks

 

It's one of the advantages of a 3-way setup. You have each driver playing in it's optimal range. My tweeters are high passed at 5k, mids at 900, and mid bass at 100. I could put a ton of power through the system without hurting anything and it will still sound clean.

FWIW, the same tweeter in the 2-way on the passives are crossed at 2k or 2.2K, can't remember so the tweeters will take it but the larger 3" mid will handle it much better.

 

Sweet. Learning A TON of info today!

I heard the Morel Elate 3-ways with the 9" midbass in the door and tweets/mids in the a-pillar yesterday.......WOW!! I think I'm in love. He had no processing though. IDmax 10" under his console too. The soundstage sound like it was sitting atop the dash and had so much depth. Sounded so natural

 

You're getting addicted lol. This is one area I can honestly say the MS8 excels at. The stage is always great. Way out on the hood up high and centered. I wish you were close enough to hear mine. I have the mid bass in the doors and the mids in the kicks and it sounds like all sound is coming from atop the hood. That's the beauty of processing, you can have a great stage without the mids on the dash in view of thieves. If you didn't know any better you would think the tweeters are playing the whole range. I still put my ear to my midbass and mids from time to time just because it's hard to believe they're playing on the floor yet the sound is coming from so high up. I LOVE the 3-ways especially for loud SQ listening even though some people say there's no difference. I've set mine up before as a 2-way eliminating the mids and while it still sounded very good, the 3-way just seemed clearer and more dynamic.

 

Yes...yes I am haha

 

Anybody why has said that there is no difference in a 3-way setup has likely never heard even a decent one. They might not like or want a 3-way, but there is a big difference.

 

Agreed. I listen to the same speakers in a 2-way config. (they were on a speaker panel BUT they had a processor on them) and they weren't even close. The depth and ease of reproduction is the only way I can describe it. Ignorance is bliss... Now I'm screwed hahah

 

I tried mine as a 2-way and recalibrated the MS8 for a 2-way. It's not that it was bad, it sounded good but it's as you said, more ease of production and to me, better clarity especially as you crank it up.

As of late, I've been a fan of running the high pass on the mids pretty high (100hz) as long as you have the processing to keep the bass up front. My midbass speakers aren't exactly cheap but there is still a difference in clarity when they're crossed over higher and the subs take some of the stress off of them. This can sound really terrible if your subs require a ton of eq to play correctly up there but you gain so much impact with a pair of 15s playing those frequencies over a pair of 6.5s. I had the door panels off the other day and checked excursion of the midbass just to see if I was pushing them anywhere near their limit. At levels higher than I ever listen to, they barely move at 100hz. This setup should keep everything well within xmax. Powerhandling should be purely thermal limited in which case I could probably run 500w+ to the mid bass for a short time with the 3" VC.

I think it's sort of the same way with the 2-way vs 3-way, the tweeters are able to play in a more efficient range and are not struggling to produce 2Khz. Before I wasn't fully taking advantage of what the 3-way had to offer. I was trying to play the mid bass too low, the mid too low and while the tweeter was not too low, they certainly sound better at high volumes at 5,000hz vs 3,500hz.

Now I have a new issue and I'm really scared. The MS8 *might* be trying to blow out my Dyns, I'm not sure yet but the problem I'm having seems to be getting more and more common and it's scary.

 

Did you get that zed yet? If so, bypass the MS8 for a while and just use the bandpass on the Zed at -12 or -24 and see if you notice any huge changes. You already know where to cross the thins. Of course, this is just for your front stage, but it might help reveal some cause and eliminate some effect for a while.

 

These damn MS8's are getting nasty. I'm seeing a bunch of "my MS8 did..." on DIYMA. I'd just use the Zed like JDA said or pick up another processor

 

You probably saw my post over there... Super loud high pitched sound, burning electronic smell that stunk the car up for a whole day. Luckily it didn't damage any speakers but judging from others' experiences I'm lucky. I didn't suspect the MS8 until others started having the exact same problem. I wonder if JBL would cover damages to speakers from a defective MS8.

 

Also, if it kills one of the Dyns and JBL doesn't cover it, I won't replace it, spending that kind of money again would leave me single.

 

Unless it's in the manual and under warranty still...I'd make sure I get that in writing! With the money those Dyn's cost, no reason to take a chance. I'd be pulling that thing

 

Luckily Andy has responded to my PMs over on DIYMA. Going to take the covers off of everything this weekend and sniff around to confirm it was the MS8 and not something else. Also got to install that cap on the tweeters.