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#61 Tritty

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Posted 16 December 2012 - 09:26 PM

That sucks that there is no stores that can help. The cross over you have mentioned is not a 3way, it only has tweeter and midrange output (no midbass) While we're on the topic of crossovers...just have a re-read of this

Whooaaaa hold up!

I only skimmed over the thread admittedly so I may have missed something, but unless you are actually using the Morel drivers that were meant for that crossover, do NOT buy that crossover.

Unless the TS specs and frequency response are a dead match for that of the Morel drivers, that crossover is not going to give you anywhere near optimal results. In fact it would probably sound for worse than simply running two-way active. If you use a driver that's not meant for the passive crossover then chances are everything from Frequency response, to impedance curve, to distortion characteristics to sensitivity are going to be VERY different.

* The crossovers are built to level match the appropriate Morel tweeter, midrange and midbass and does so by attenuating some of those drivers by a certain degree so that they are all at an even level. If your drivers have an uneven sensitivity then the drivers will not be properly level matched - even if you have gain adjustment on the crossovers they are usually only by 1dB or 2dB increments which are usually still not good enough to get it as accurate as you want it.

* Incorrect impedance curves will throw off the entire crossover point and slope, and could throw it off to the point where a 3khz crossover point on your tweeter could change to 1.5khz, as a result frying your tweeter (or to 5khz, causing a massive hole).

* If the crossover has a specific slope tailored to the FR of the original drivers, then if your drivers have a totally different FR (which they probably will) then the slope wont match and the integration will be either peaky or filled with holes.

To cut a long story short you NEVER want to use a passive crossover for any drivers other than the ones it's designed for. Best case scenario it'll sound bad, worst case scenario it may cause damage to your components. If the drivers you use are DIY drivers sold by Madisound then they actually offer a service whereby they will custom-design a 3-way passive crossover for you. For an extra cost they can and will even assemble it for you using your choice of components. If you need to go the passive route it is a much better option then buying a random crossover and hoping it will work, and it will probably work out cheaper too.


Edited by Tritty, 16 December 2012 - 09:29 PM.


#62 soundvanman

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Posted 17 December 2012 - 05:33 AM

Yeah none of the stores are real real good! Best one only sells Alpine... And there expensive. I need to get in the van and head up Melbourne way soon.

#63 soundvanman

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Posted 17 December 2012 - 03:47 PM

So I am probably going to be running 2 way active soon with my PDX! Wondering people thoughts on where to set crossovers for high and low on amp and in head unit?

It's for some Supremos and Elate 9s! 2way active will be temporary until I save a little cash for the rest of install! Supremos on front Rcas and Elates on rears. No sub at this time.

#64 Tritty

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Posted 17 December 2012 - 05:41 PM

The PDX amp and your head unit does not have a high enough LPF for the mids or a high enough HPF for the tweeters.... As mentioned previously.. You will need the PPI amplifiers.

I think you should stick to a fully passive system until you have researched/learnt about what is involved in running active

#65 soundvanman

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Posted 17 December 2012 - 06:52 PM

So the headunits crossovers for low, mid low, mid high and high are completely useless to me, even if I turn the crossovers off on the PDX? and use there headunit crossovers on there own? This is what they can be set to

Select the desired cut-off frequency (Crossover Point) by sliding your finger on the GlideTouch bar to the left or right.

Adjustable frequency bands:
LOW: 20Hz to 200Hz (in 1/3 octave steps) MID-L: 20Hz to 200Hz (in 1/3 octave steps) MID-H: 20Hz to 20kHz (in 1/3 octave steps) HIGH: 1kHz to 20 kHz (in 1/3 octave steps)

2 WAY System

3 Press BAND to select the band to be adjusted.
LOW MID HIGH LOW (SUBW) (REAR) (FRONT) (SUBW)

4 Select the desired cut-off frequency (Crossover Point) by sliding your finger on the GlideTouch bar to the left or right.
Adjustable frequency bands: 20Hz to 200Hz (in 1/3 octave steps)

5 Press SOURCE/POWER to adjust the slope. Adjustable slope: 0 (FLAT), 1 (6dB/oct.), 2 (12dB/oct.) 3 (18dB/oct.) 4 (24dB/oct.)

6 Adjust the output level by turning the Rotary encoder. Adjustable output level: -12 to 0 dB.

7 To adjust another band, repeat steps 3 to 6, then adjust all bands.

8 When the setting has been completed, press FUNC. or the GlideTouch bar to activate the preset mode.

9 Select any one of the preset numbers (1 through 6) by sliding your finger on the GlideTouch bar to the left or right. Press and hold the GlideTouch bar under the desired preset for at least 2 seconds to store the adjusted contents.

Edited by soundvanman, 17 December 2012 - 07:15 PM.


#66 jamiebosco

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Posted 17 December 2012 - 07:16 PM

The PDX amp and your head unit does not have a high enough LPF for the mids or a high enough HPF for the tweeters.... As mentioned previously.. You will need the PPI amplifiers.

I think you should stick to a fully passive system until you have researched/learnt about what is involved in running active

????
Run in 3-way mode he can:

HP the Elate 9 between 20hz-200hz and LP between 20hz-20khz @Flat,6,12,18,24dB/oct
HP the Supremo between 1khz-20khz @6,12,18,24dB/oct

Which should be perfect.

Personally I'd try the Elate 9's BP at 80hz - 1.5khz @ 12dB and the Supremo's HP at 2khz+ @ 24dB.

I don't think you'll get much more than 1.5khz out of the 9" woofer,they are more suited to a 3-way front stage

Edit:Soundvanman's edit beat me too it! lol

Edited by jamiebosco, 17 December 2012 - 07:17 PM.


#67 Tritty

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Posted 17 December 2012 - 07:20 PM

^^^ my mistake :( I had forgotten the fact you have a 3 way capable head unit... As Jamie mentioned, you will be fine :) sorry bud

Edited by Tritty, 17 December 2012 - 07:23 PM.


#68 soundvanman

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Posted 17 December 2012 - 07:37 PM

????
Run in 3-way mode he can:

HP the Elate 9 between 20hz-200hz and LP between 20hz-20khz @Flat,6,12,18,24dB/oct
HP the Supremo between 1khz-20khz @6,12,18,24dB/oct

Which should be perfect.

Personally I'd try the Elate 9's BP at 80hz - 1.5khz @ 12dB and the Supremo's HP at 2khz+ @ 24dB.

I don't think you'll get much more than 1.5khz out of the 9" woofer,they are more suited to a 3-way front stage

Edit:Soundvanman's edit beat me too it! lol


So now this is the tricky part... My headunits installed and set on 3way... I set low on crossover to 80hz and mid low to 80hz and the mid high to 1.5khz and then set high to 2khz... so tweeter should play 2khz and up? and mid should be between 80 - 1.5khz... and I turn all crossovers off on amp?

#69 jamiebosco

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Posted 17 December 2012 - 08:09 PM

So now this is the tricky part... My headunits installed and set on 3way... I set low on crossover to 80hz and mid low to 80hz and the mid high to 1.5khz and then set high to 2khz... so tweeter should play 2khz and up? and mid should be between 80 - 1.5khz... and I turn all crossovers off on amp?


Yeah basically.
On my headunit you use the "Source" button to change the slope (dB/oct) If you decide to go with the low (2khz) crossover point on the tweeters make sure you have a steep slope in place first
Personally,I'd start the High channel off at 4khz @24db and bring it down from there
You will have to experiment a little to get them to blend in together,make sure you use commmon sense and double check everthing you do

#70 soundvanman

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Posted 17 December 2012 - 08:46 PM

Yeah basically.
On my headunit you use the "Source" button to change the slope (dB/oct) If you decide to go with the low (2khz) crossover point on the tweeters make sure you have a steep slope in place first
Personally,I'd start the High channel off at 4khz @24db and bring it down from there
You will have to experiment a little to get them to blend in together,make sure you use commmon sense and double check everthing you do


Yeah I'll be going slow because I do not way anything to fry! I should keep gains on amp very low or right down?

#71 soundvanman

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Posted 17 December 2012 - 10:45 PM

So I purchased the PPI because they were close to selling out! So now I just need to wait and watch my letter box!

#72 soundvanman

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Posted 17 December 2012 - 11:10 PM

And I was looking at the JL amps they seem to have decent crossovers

#73 muzzy66

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Posted 18 December 2012 - 11:40 AM

I'm going to but this out there straight up.

It is a complete and utter waste of time going three-way if you are going to do it via some dodgy half-arsed method. It's utterly pointless. A three-way active front stages is one of the most challenging things to set up when it comes to car audio - you have 7 crossover points, 7 crossover slopes and 4 gain levels that all need to be setup near perfectly in order for a 3-way active front stage to sound any good. Then on top of that unless the mids and highs are on a common baffle and equidistant you're going to need time alignment too. You aren't going to get anything resembling optimal results by screwing around with RCA splitters, horribly innaccurate amp crossovers (with little or no selectable slope adjustment), horribly innaccurage gain knobs to level match and zero time alignment.

If you're going to go 3-way active + sub then you need a proper 4-way active digital processor (either built into the head unit or a seperate extenal unit) otherwise you are wasting your time. If you try to do it using the method above then your results will most likely be worse then if you simply ran two-way passive. If you are cash limited and can't afford the extra processing or amp channels, and you MUST go three-way, then I'd recommend buying a set of three way splits and sticking with the factory passives. It's not going to let you optimise for your interior, but at least it wiill be optimised for the drivers.

Edited by muzzy66, 18 December 2012 - 11:43 AM.


#74 TMM

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Posted 22 December 2012 - 03:32 PM

Theres nothing wrong with passive although if you own the equipment to set it up properly then you can probably afford to go active anyway...

#75 GRPABT1

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Posted 22 December 2012 - 05:00 PM

SQ comp cars aside, most people want front and rear speakers for ambience and a bloody decent sub or two alright ones. Active sounds great and all but the sheer amount of amps, cabling, processing etc needed to have a front and rear setup makes passive much more attractive, even with a really good head unit or processor to help tune.

#76 IamtheSteg

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Posted 22 December 2012 - 06:42 PM

I don't know about most people...
Plenty of ppl run rear fill and plenty more don't - I never got the point of it myself as the sound of a cheap co-ax mounted down low in and faded mostly out as in a typical rear door application, or a pair of sikbenines in a shelf at the back add nothing to rear passenger enjoyment IMHO.

I've always been happiest getting the front sorted as you'll hear it from the back seat anyway...

#77 Tritty

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Posted 22 December 2012 - 07:19 PM

Most of my customers are happy to drop the rear speakers in favour of some higher priced front splits, a select few will take up the choice of going active aswell and none of them have looked back. 90% of customers don't realize that you can still have excellent sound without rear speakers...they just assume that because their car (and most of their friends cars) has 2 sets of speakers in it, they have to put 2 sets back in. Same goes for subs, most people just assume they are for di**head teenagers who like to wake up the neighbors and do nothing for a sound system..once they have been shown what a sub is for and how it greatly improves their stereo, they end up purchasing one and loving it. I think the point of my rant? Is that most people are happy to install front and rear speakers unless they have been told/shown that it is not always necessary and for them to know the advantages and disadvantages of both systems.

Just my 2c :)

#78 GRPABT1

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Posted 22 December 2012 - 10:26 PM

I personally hate all the sound coming from in front of me. I like a sense of ambience in a car that rear fill can help with.

That aside I have ever owned a high level active setup tuned greatly to emulate that kind of sound. I'm led to believe this is possible, but I doubt it's easy for the inexperienced.

#79 Tritty

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Posted 22 December 2012 - 10:35 PM

Each to their own :) it definitely is possible, you should attend an SQ comp local to you if possible and have a listen to some high end audio setups :) its not too hard to setup an active front stage, Half the fun is learing how to set it up an the othe half is just tuning it and making it sound better and better each time you tune it

Edited by Tritty, 22 December 2012 - 10:36 PM.


#80 soundvanman

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Posted 23 December 2012 - 09:12 PM

Well I think I'll probably end up going tweeter n mods from the PPI when it arrives on front and rear RCA's then run the midbass from Sub RCA until I decide what subs to run etc.

Each to their own :) it definitely is possible, you should attend an SQ comp local to you if possible and have a listen to some high end audio setups :) its not too hard to setup an active front stage, Half the fun is learing how to set it up an the othe half is just tuning it and making it sound better and better each time you tune it


I do plan on attending some car event locally! That's my goal next year... Maybe even enter some. Oh and I know this was directed to a different member but oh well.

Edited by soundvanman, 23 December 2012 - 09:13 PM.


#81 Tritty

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Posted 23 December 2012 - 09:25 PM

That's great that you plan on competing mate :)

#82 GRPABT1

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Posted 23 December 2012 - 09:40 PM

LOL comp near me? That's funny

#83 Tritty

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Posted 23 December 2012 - 09:43 PM

There's one on the 19th January @ Autobarn Bundall.

Edited by Tritty, 24 December 2012 - 08:38 AM.


#84 muzzy66

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Posted 24 December 2012 - 05:00 PM

I personally hate all the sound coming from in front of me. I like a sense of ambience in a car that rear fill can help with.

That aside I have ever owned a high level active setup tuned greatly to emulate that kind of sound. I'm led to believe this is possible, but I doubt it's easy for the inexperienced.


I used to think this when I started out - my was of thinking was that having rears as well helped to fill the entire interior with sound, and to me at the time that sounded better then the comparatively 'one dimensional' approach of having fronts only.

But it all depends on how anal you are about accurate sound.

When you have rear speakers playing the same information as your front speakers, you end up with what is (IMHO) mess. Different speakers will have different tonal characteristics, and even if you use the SAME speakers their difference in location relative to the listening position means that the sonic characteristics will differ. The result is that the sound ends up all over the place and there is no coherence or accuracy at all to the presentation.

When the speakers are purely in front of you, all of the sound is coming from the single (relative) position - it's closer to a point source. It's easier to control things like frequency response, phase response and timing. It also gives you the obvious benefit of a more defined sound stage, if that's important to the individual. From my past experience these things are sacrificed if you have rears unless you VERY heavilly attenuate them - even if you do, I've found they still interfere with the sound accuracy. Plus if you're going to turn them right down, what's the point of having them?

I will certainly agree that Active can be a challenge to those who don't have experience with tuning and audio. With advice from those in the know however, you can get some great results from an active system on a VERY low budget. You can put together an outstanding quality 2-way active front stage with a total budget of $300 in speaker drivers. You would need to spend $1,000+ to even come close to matching that quality from a passive retail set.

The downside of course is that it costs you a little more in amplification - instead of three channels, you need five. You also need a capable processor to make it worth your while, Between the two that's probably at leas $1,200 - $1,500 extra expenditure. Once you subtrace the $700 or so you are saving on tweeters that's probably an extra $700 or so you have to spend for an active system versus a passive, but properly tuned the active set will probably sound better 9 times out of 10.

You need to be patient though. It takes time to get your head around the tuning requirements and work out how to get best results. If you have an installer who can install and tune it for you using an RTA (to match accurately driver output levels) then you should be able to get very good results.

#85 zion187reigneth

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Posted 24 December 2012 - 11:04 PM

Active setup seems to be neccessary for most guys who go through the audio scene, its an important part of the learning curve.

#86 GRPABT1

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Posted 27 December 2012 - 08:53 AM

I don't think I want to get that involved. I like my music loud and clear but I'm not that fussed on the minute details.

#87 soundvanman

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Posted 29 December 2012 - 10:22 PM

So could this RF Symmetry EPX2 with 28 Band EQ Card which is in the for sale section at the moment help me in my search to run active? Read it is crossovers for 10channels.

#88 jamiebosco

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Posted 29 December 2012 - 11:53 PM

So could this RF Symmetry EPX2 with 28 Band EQ Card which is in the for sale section at the moment help me in my search to run active? Read it is crossovers for 10channels.


If it's the one I'm thinking of (from the 90's??) I think it does 2-way active front + sub,not sure though

Keep an eye out on the forum (and ebay maybe) for a used Alpine H701+C701,they pop up from time to time and will probably be the cheapest way to get a good 8Ch processor in your rig.

#89 TMM

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Posted 30 December 2012 - 12:12 AM

The EPX2 is pretty outdated by todays standards. It seems to have all the bases covered except for relatively shallow crossover slopes (12dB/octave) and as far as i can tell, lacking of any form of time alignment.

Time alignment is the most useful feature of any active* system imo - by delaying each speaker by a small amount (milliseconds) differences in the distances of the speakers to the listener can be compensated for. Therefore when set up properly the sounds from speakers on the passenger side (which are far away) arrive at the exact same moment as the sounds from the speakers on the drivers side. This also helps make speakers 'disappear' and be hard to audibly locate.

*by active i mean a digital crossover. Using the crossovers on the inputs of an amplifier is still a passive system imo as they use passive components - no different to a speaker level passive crossover, you are just implementing it at a different part of the signal chain so the net result is the same.

Edited by TMM, 30 December 2012 - 12:18 AM.


#90 soundvanman

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Posted 30 December 2012 - 07:16 AM

The H800 no good?