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Discussion Starter #1
Hey Forum peeps!

I have the CDM88's paired with the Piccolo's.

Currently running the CDM88's from 800hz - 6500khz

The spec's show that 450-7000Hz is their range.

My question is should the Max Freq range be utilized or is it better to keep them below the max...It's been difficult to tell the difference between different adjustments after a certain point.

Hope that makes sense.
 

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I dont know anything about these specifically. but most of the time the freq response spec and what can actually be used are two different things.

ex: tweeter with freq response of 1500-20000. you cant(and shouldnt) REALLY cross it at 1500.
 

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Discussion Starter #3
Thanks for the input...can you elaborate on why that is? Referring to your example?
 

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For a particular drivers, you shall not play close to their FS value. Always cross 2X from its value will be a good start....
Steeper slope can help on this, like you set the slope at -36dB you can play it close to its FS value(still, the risk is there) but it may give you phase issues...
 

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Discussion Starter #5
^thanks for the input! That's the most info I ever heard regarding mids.
I have a max slope of 24db with the MS8 and have played them as low as 400-450ish but they sounded like they were straining. Does the same principle apply to the top end?
 

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Wrong... The higher you crossover, the closer the mid and tweeter need to be. Home audio crossovers would never cross at 7kHz because the center-to-center spacing required between the mid and tweeter will be closer than they are physically able to get. You can rarely do things in the car that you can in home speakers - some compromises will need to be made - but do try to keep them at a minimum.

Cross in the 3000-4000 area and try to keep the tweeter as close to the the mid as possible. Righttttt next to each other is very much ideal.
 

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Discussion Starter #9
Wrong... The higher you crossover, the closer the mid and tweeter need to be. Home audio crossovers would never cross at 7kHz because the center-to-center spacing required between the mid and tweeter will be closer than they are physically able to get. You can rarely do things in the car that you can in home speakers - some compromises will need to be made - but do try to keep them at a minimum.

Cross in the 3000-4000 area and try to keep the tweeter as close to the the mid as possible. Righttttt next to each other is very much ideal.
^^ My mids and tweets are both in the a-pillar right on top of one another... :)
 

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Discussion Starter #10
Have you tried using the piccolos at 1.something Khz without the cdm88?
elparner, I have had both the pleasure and misfortune of playing the piccolos solo...I had a bad mid this year and was forced to play in two way mode for over 3 months. I played them as high as 1.8khz...but kept them right around 2khz most of the time. At times I really thought I would'nt miss my CDM88's but they do make a difference in my set-up :)
 

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The correct answer to the question is to used the information below. Use the settings from the morel passive units as a baseline, then fine tune from that.





ACCUSET MX-33.4E
The Accuset MX-33.4E 3-way crossover ensures optimal customization to various car environments through tweeter level attenuation and slope roll off selection. The Accuset MX-33.4E allows easy adjustment of the crossovers (6dB or 12dB slope adjustment and 4dB - in 2dB steps - tweeter level attenuation settings). The easy-to-use system enables optimal soundstage and performance.


SPECIFICATIONS

SPECIFICATIONS Accuset MX-33.4E
Nominal Impedance 4 Ohm
Power Handling 250W
Crossover Point Power Handling Woofer: 700 Hz/12dB
Midrange: low 700dB 6dB, High 3800Hz 6/12dB (Variable)
Tweeter: 3800Hz 6/12dB (Variable)
Crossover Controls Midrange upper frequency Slope Cut: 6/12dB
Midrange Level: -2dB, 0dB, +2dB
Tweeter Frequency Slope Cut: 6/12dB/Octave
Tweeter Level: -2dB, 0dB, +2dB

Wiring options Standard, bi-amp, bi-wire


ACCUSET MX-33.3
The Accuset MX-33.3 3-way crossover ensures optimal customization to various car environments through tweeter level attenuation and slope roll off selection. The Accuset MX-33.3 allows easy adjustment of the crossovers (6dB or 12dB slope adjustment and 4dB - in 2dB steps - tweeter level attenuation settings). The easy-to-use system enables optimal soundstage and performance.


SPECIFICATIONS

SPECIFICATIONS Accuset MX-33.3
Nominal Impedance 4 Ohm
Power Handling 250W
Crossover Point Power Handling Woofer: 300 Hz/12dB
Midrange: low 300dB 6dB, High 3800Hz 6/12dB (Variable)
Tweeter: 3800Hz 6/12dB (Variable)
Crossover Controls Midrange upper frequency Slope Cut: 6/12dB
Midrange Level: -2dB, 0dB, +2dB
Tweeter Frequency Slope Cut: 6/12dB/Octave

Tweeter Level: -2dB, 0dB, +2dB
Wiring options Standard, bi-amp, bi-wire


Crossover Accuset MX-33.3LE
Nominal Impedance 4 Ohm
Power Handling 250W
Crossover Point Power Handling Woofer: 380Hz / 12dB
Midrange: Low 300dB 6dB, High 3800Hz 6/12dB (Variable)
Tweeter: 3800Hz 6/12dB (Variable)


Crossover Controls Midrange upper frequency slope cut: 6/12dB
Midrange level: -2dB, 0dB, +2dB
Tweeter frequency slope cut: 6/12dB / octave
Tweeter level: -2dB, 0dB, +2dB

Wiring options Standard, bi-amp, bi-wire
Housing Material Die-cast aluminum
Terminal Type Fully insulated gold plated screw taps
Net Weight 1.20 Kg (2.65lb)




.
 

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For once I'll agree with Kyheng about the xo on the morel. Look at the FR here While the driver is rated down to 450hz, its pretty useless below like 1khz. Then at the top it starts rolling off around 5khz. It's choppy as hell between 1 and 5.

Crossing at 7khz is way way to high. It's already down -5db at 7khz. Now this is how a good mid should measure. Razor flat from 200-2khz, usable up to 3khz.
 

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For once I'll agree with Kyheng about the xo on the morel. Look at the FR here While the driver is rated down to 450hz, its pretty useless below like 1khz. Then at the top it starts rolling off around 5khz. It's choppy as hell between 1 and 5.

Crossing at 7khz is way way to high. It's already down -5db at 7khz. Now this is how a good mid should measure. Razor flat from 200-2khz, usable up to 3khz.


You are expecting a dome to perform like a cone? They are michanically different with the advantage more in favor of the cone.

Lets just say on topic unless, the original poster ask for other options in midrange.


.
 

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A mid range is supposed to play a certain part of the audio spectrum. Some will be better than others. Don't diffuse the issue. BTW how come you don't use spell check?
 

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The OP seemed more concerned with the high end of the speaker frequency response, not the lower end. FWIW 800 hz seems fine as I've heard these very same speakers get by at 300 off the passives.

As for crossing up top, use your ears. Generally speaking, a higher crossover point to the tweeters is preferable so long as the mid can play flat to that region with no cone breakup.

In many ways, crossing over at 3-4 khz seems like a waste of a good dome mid. Why even go 3 way at that point?
 

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Discussion Starter #16
@evo9,

I actually re-referenced the mfg xover recommendations you posted and I actually like it! LOL The CDM88's are playing 800-3800 and piccolos 3800 and up now but with a 24DB slope. My initial impressions are that the stage is more coherent and detailed and I'm noticing more dynamics as well. Now, I had a great stage before with the previous settings at CDM88 800-6500 and piccolo from 6500 and up...But now it seems that the more conservative settings are capturing the details that I was trying to EQ' in with the previous settings. My moderate-noob level experience with tuning was leading me to think that the more extreme xover settings would lead to a more extreme sound in terms of detail and dynamics but I seem to be getting exactly what I want with the more conservative settings at this time. weird...but good :)
 

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Well, it is 89dB @2.83V/1M, convert it back to 1W/1M it will be about ~84-85dB.... So placement are very important...
But such driver are good as it will sound warm and won't be harsh even you crank the volume up....
Depending on location of the mid, I may cross it higher and see how it goes, if it is installed under the dashboard, it will sound good. But if it is installed facing you directly, it will be another story...
In audio, there's no right or wrong, that's another reason why I prefer an active HU at all times, I can adjust the settings whenever I wanted to.
Have to know that, when your car are moving fast, it may sound differently compoare to when your car are not moving...
 

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Cross in the 3000-4000 area and try to keep the tweeter as close to the the mid as possible. Righttttt next to each other is very much ideal.
It has been noted by Lycan that as long as the vertical plane remains the same you can separate the tweeter as much as you like (in a car) with little/no problems. Meaning a midrange in the kick and tweeter in a-pillar is a proven solution in the car. This exact finding has also been noted by Andy Wehmeyer in reference to tuning the MS8.

However, not everything works in every vehicle...so testing is the best policy.

Sounds nice. Got any pics? I'd like to see how you did that, as I've been considering trying something like that myself.
Just to warn, a dome midrange is VERY hard to tune and get right in the a-pillar due to the tremendous off axis response - meaning you will be experiencing reflections/smearing coming out your wazoo. Also, side biased is extreme. With that said, the kick area is a great place for a dome midrange and it will excel down there (way fewer reflected surfaces and more equal path length distance).

Again, it is not that you can't have a dome in the pillar sound good, but are you really going to spend the countless hours mocking up different angles and placement to get exact, then tuning and tuning and tuning!
 

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Well, I wouldn't be using a Morel driver, anyway. I'm not a Morel fan, personally. I've just never done the finish work to implement a 3-way. My expertise is more in the electronics stuff than the finish stuff. (I know there are other threads of people doing custom 3-way setups, but the more the merrier.)
 
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