Printer Friendly Forum Posts - Front sound stage

Hey guy's,

It's been a little while since I have posted. Here goes my latest, I am currently working with the front soundstage in my 94 Lumina Euro. I have built a pair of temporary enclosures for the doors that will hold 2 6.5" midbass's each. I have mounted the tweeter in the upper section of the door and will also have a second tweeter mounted in the factory 4x6 location up on the dash.

The question, Should I run them in a 2 way configuration or would it be better to run them in a 3 way confiuration?

If anyone thinks that the 3-way would be best, them should I put together my own crossovers or does anyone know where I can pick up a decent set of 3-ways?

Also, I am thinking about not running the rear channel and bridging my cadence Q400 for the front channel. Any inputs on this?

Here is a link to a pickture of the door panel.

https://pg.photos.yahoo.com/ph/racer4272000/detail?.dir=eddf&.dnm=f796.jpg&.src=ph

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Alpine CDA-9833 HU
Diamond Audio M661 Components
MTX Thunder T6.6 Components:rear fill:
Cadence Q400 4 Channel Mains + rears
Thunder 801D Subs
MTX 1004 10's
Dual 4g wire to rear
4g grounds

I definately reccomend the alpine type-x system, i love em

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2003 Chevy Avalanche,Eclipse CD7000,Morel Elate 5,Adire Extremis,Alpine PDX-4.150, 15" TC-3000, 2 Alpine PDX-1.1000, 470Amp HO Alt.

I will be running 2 sets of MTX Thunder 6.6 components for now untill I can save up enough money for the MB Quarts that I want.

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Alpine CDA-9833 HU
Diamond Audio M661 Components
MTX Thunder T6.6 Components:rear fill:
Cadence Q400 4 Channel Mains + rears
Thunder 801D Subs
MTX 1004 10's
Dual 4g wire to rear
4g grounds

I recommend making it a 2-way system just for the simple fact that you'll only have one crossover instead of two. In the audiophile world it's generally thought that the less crossovers, the better. I have found that most of the time this is true.

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Ok, but, If I run 4 speakers off of a single crossover will it not overload that crossover? I have read that crossovers are matched to speakers per their Ohm rating, is this true? And If I were to run them as a 3 way set-up, I would use a set of 3 way cross overs. I just don't know where to get ahold of a set.

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Alpine CDA-9833 HU
Diamond Audio M661 Components
MTX Thunder T6.6 Components:rear fill:
Cadence Q400 4 Channel Mains + rears
Thunder 801D Subs
MTX 1004 10's
Dual 4g wire to rear
4g grounds

You could make them yourself:

Passive Crossovers

However, the system would function more efficiently if you were to use an active crossover prior to the amplifier. You can find a decent active crossover for around $200

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WTB: Black Leather Acura GSR seats

Hmm. What's your goal here? If it is sound quality I think you need some redirection. If it is SPL, whatever will be fine.

My advice:

1) A stereo system should have 2 tweeters - one for each channel - remove the extra one tweeters.

2) Tweeters should be as close as possible to the midrange driver. Within 5 inches. Get rid of the tweeters in the dash. Move the door tweeters closer to the midrange drivers.

3) Close one 6.5" off from the other. Run them as a 3-way system. Use a standard 2-way crossover for one of the 6.5" drivers and the tweeter. Buy another 6.5" for use as a dedicated midbass driver. Use an electronic crossover to cross between the component pair and the midbass drivers. Try a 350hz crossover point. If you need an electronic crossover AudioControl makes some nice ones.

If you can't close one 6.5" off from the other then run them as a 2-way system. Repeat. Do not run them 3-way unless you can seal the 6.5" off from eachother. You'll probably need to design a custom crossover for this setup - or bi-amp and use NO passive crossover.

Don't bridge mains to mono. Ever. If you plan on doing this there's really no point in working on your "front stage."

Anyway. Let me know what you think of my recommendations.

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New Project: 2003 Pathfinder

I think your recommendations are spot on, as usual.

Steven Kephart

Adire Audio

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Those are some good points.

I can seal off the enclosure using some MDF and a little fiberglass. And will run them in a three way configuration.

On that note, I just received and E-Mail from a friend of mine regarding this issue, He works for a local install shop and he states that I should use a decent three way passive crossover such as an MB Quart QM 300.72 Passive crossover. Will this work ?

And By the way, I am looking for SQ and not SPL. I am a SQ freak, HA HA

Going off topic a little, I am using a downfiring sub box the I built with 2 10's, At the moment I think that it pounds hard and sounds good. Any input as to the advantages and disadvantages to this type of set-up? I am using 2 MTX 1004's and a MTX thunder 6500 to power them. The box is right behind the rear seat in a 94 Lumina.

Passive crossovers are designed for particular speakers. I don't suggest using one designed for speakers you don't own.

There are real benefits to bi-amping the midbass portion of a 3-way system. See https://sound.westhost.com/bi-amp.htm

I think the best solution would be as I said above. Regular 2-way component set + electronic crossover between component set and midbass drivers. Run the entire front stage off your Cadence. Forget about the Alpine 6x9's or run them off your deck heavily attenutated.

I scrolled through your pictures. Your sub box looks good. A sealed box is right for SQ. Good job.

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New Project: 2003 Pathfinder

kfr sucks! Yeah.... Can someone explain what bi-amping is please? And downfiring subs? Keep seeing it, not really sure what it means. BTW you know I was joking, right? Atleast concerning kfr. :)

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1998 Monte Carlo w/
Eclipse CD8454
2xRockford 5.25" Power 2-way T152C
2xRockford 6"x9" Punch 3-way FRC4369
1xMemphis 16-MCH1300 5-channel
2xKicker 12" L5 Solobaric-2 Ohm

A picture is worth a thousand words.

posted_image

Paul

Thanks for the pictures.

Bi-amping means using separate amplifier channels for separate drivers or sets of drivers. It usually implies an electronic crossover BEFORE the amplifier stage.

Technically this is what you do with your subwoofer. It is being run off a different amplifier channel than your mains. It has a low pass electronic crossover. You should also have a high pass electronic crossover operating on your mains. This way the main amplifier and main speakers handle everything above the frequencies the subwoofer handles. The subwoofer handles everything below the mains.

When I say bi-amp the main components and a pair of midbass speakers I mean that you should do this division again.

Amp Channels 1 and 2 = regular components ... high passed at 350hz.
Amp Channels 3 and 4 = midbass drivers ... low passed at 350hz, high passed at 80hz
Amp Channel 5 = subwoofer driver ... low passed at 80hz.

So you see, each amplifier channel handles a separate chunk of the frequency range. This relieves both the speakers and the amplifier. Speakers and amplifiers operate cleaner and more efficiently (in general) when they are asked to do less.

Now, after this brief and overly general explanation read that article I posted. It will explain why bi-amping between the midrange and midbass drivers is so beneficial.

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New Project: 2003 Pathfinder

Thats a really good explaination and diagram.

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Nik
Jeeputer Progress
[|||||||||||-] 90%
Check it out.

Thanks for the help guy's. After doing some research I have decided to go the Bi-amping direction with a Audiocontrol DXS Digital crossover.

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Alpine CDA-9833 HU
Diamond Audio M661 Components
MTX Thunder T6.6 Components:rear fill:
Cadence Q400 4 Channel Mains + rears
Thunder 801D Subs
MTX 1004 10's
Dual 4g wire to rear
4g grounds

Wow! Excellent choice. Please report back about how your system turns out.

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New Project: 2003 Pathfinder

Weee, I love informative stuff. Thanks guys. (THe downfiring was kinda self explanatory, just wasn't 100% sure. What are the advantages of that?)

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1998 Monte Carlo w/
Eclipse CD8454
2xRockford 5.25" Power 2-way T152C
2xRockford 6"x9" Punch 3-way FRC4369
1xMemphis 16-MCH1300 5-channel
2xKicker 12" L5 Solobaric-2 Ohm

Thats about the nicest (most expensive) crossover you can get.

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Nik
Jeeputer Progress
[|||||||||||-] 90%
Check it out.

AS for downfiring subs, I don't think there is any advantage over regular setup. The only one I can think of is if you have stuff in your trunk and you brake hard or take a fast turn, stuff may or may not hit your subs. You wouldn't have that problem with downfiring.

Paul

Well, yes it is one of the most expensive crossovers around but, I will be able to add the optional dash mounted control so, that I can adjust the settings according to the specific music that I am listening to at the time. I listen to a wide variety of music so, the ease and flexability of this crossover will come in very handy.

Chris

I don't see a need for changing the crossovers on the fly. Once you find a point that is the most efficient for your speakers, you should leave it there.

Paul

I am now looking to go a different route possably. I might purchase an Alpine CDA_9833 and use the built in 3 way crossover in the radio vers. going with a seperate crossover. What are your opinions there?

Chris

Less components = less noise. If you can select the crossover points then I'd say go with it. (When I say select the points I dont mean from a preset list of points. e.g 60, 80, 125 for lowpass ect.)

Paul

The 9833 has a fully adjustable crossover, So, This is a good thing.

Chris

Here are the specs for the crossover.

6-Position Digital Crossover with Adjustable Slope: The digital crossover allows you to choose from the following modes:

2-way Mode: A continuously variable 20-200Hz low-pass filter is available for the subwoofer outputs, and a continuously variable 20-200Hz high-pass filter is available for the front and rear preamp outputs. The slope for each filter can be set to 6, 12, 18, or 24dB/octave, or Flat. The level for each filter can be adjusted from 0 to -12dB.
3-way Mode: A continuously variable 20-200Hz low-pass filter is available for the subwoofer outputs, and a continuously variable 1-20kHz high-pass filter is available for the front preamp outputs. The rear preamp outputs have a continuously variable 20Hz-20kHz low-pass filter and a continuously variable 20-200Hz high-pass filter. The slope for each filter can be set to 6, 12, 18, or 24dB/octave, or Flat. The level for each filter can be adjusted from 0 to -12dB

Well... I'd double check their definition of "continuously variable."

Eclipse also calls their head unit xo's that, but I only get like 63hz/80hz/100hz/160hz/200hz/ to 20khz etc....

Anyway, it ends up being _near_ variable. Which might be fine, but I'd like to set my crossover at 2.4khz. I can't. The closest I can get is 2.5khz. Something to think about.

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New Project: 2003 Pathfinder

I just checked up on that and the Alpine is the same, near variable. Bit, I don't think that will be a major issue. I just want to get away from having to install too many components.

Chris

racer, I understand, I use my head unit at 2.5khz anyway for the same reason. :-)

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New Project: 2003 Pathfinder

But, in your opinion, should I go with the head unit or seperate crossover?

Chris

I use my head unit. I see no reason for the separate xo unless you want to go 4-way or need different xo points.

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New Project: 2003 Pathfinder

Ok, I am gonna go that route then. Cruthfield has the 9833 on sale for $299 which is a hell of a good deal.

Chris

Hey guy's,

Just an update, I received my Alpine 9833 the other day and Finally got to install it today. I am still playing around with the crossover, EQ and Time correction but, so far, I am very impressed. I think the system sounds much better Bi-amped vers. using the passive crossovers. Unfortunatly, my sub amp took a crap on me. I am sending it to MTX to have it fixed and will hopefully have it back in a few weeks. Thanks for all the good advice.

Chris

kfr01] wrote:

/p>
Channels 1 and 2 = regular components ... high passed at 350hz.
Amp Channels 3 and 4 = midbass drivers ... low passed at 350hz, high passed at 80hz
Amp Channel 5 = subwoofer driver ... low passed at 80hz.

This is pretty much how i had it in my 91 caprice except a little tweaking to it. Had the 6 1/2 comp. running 90hz+ and instead of 2 midbass drivers i had a single 8ohm 2 "center channel running bridged off the rear at 350hz+. a seperate 2ch amplifier for an 8" midbass downfiring under the dash at 150Hz and below and a mono amp for the 12 in woofer in the back playing 100hz and below. im duplicating the same thing in my current vehicle except going to be using a jl 6 1/2 downfiring microsub instead of an 8" under the dash. the components are running off of their crossovers with no help from the amplifier or crossover on the headunit and have the tweeters attenuated at -3db. there is a major lack of midbass when using the crossover in the eclipse headunit which ive noticed. i still need to aim the tweeters in the factory location but other than that, its about as good as it was in my caprice. i guess it just goes to show with a little ingenuity (sp?) theres nothing you cant do. posted_image

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