# difference between active crossover and dsp?



## fulletal7777 (Jun 11, 2014)

it seems to me that they are both the same thing. am i right, or are there any differences?


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## Victor_inox (Apr 27, 2012)

no time alignment in crossovers. or phase or EQ.


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## fulletal7777 (Jun 11, 2014)

ok i know time alignment, but what is phaze? and as far as eq goes, would i be able to adjust it from my hu? so a dsp is basically just a badass active crossover?


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## gijoe (Mar 25, 2008)

A passive crossover (little box that you wire your mid and tweet to) is built up of discrete components (resistors, capacitors, etc.) a single full range signal goes into the crossover and the crossover splits the frequencies to each speaker. Because the passive crossover is built from discrete components the frequencies and slopes are set in stone, you may be able to attenuate things, but usually that's about it. The problem with this is that in a car the mounting locations vary dramatically from car to car and the crossover frequencies and slopes may not be ideal for your particular acoustic environment. 

A DSP does the same thing and more, it usually adds many features like time alignment and EQ to further customize the sound, plus the crossover frequencies and slopes are variable, so you can adjust them to fit your environment, so you are no longer stuck with the passives that may or may not be ideal for your car.

Another BIG advantage of running an active system instead of a passive one is that the options for speakers is much, much bigger. You aren't limited to car audio brands that charge for the logo, and you don't have to pay for the passive crossover. The raw speakers that are available are often either copied or rebranded by car audio companies, plus there are many more options for raw speakers than for pre-built sets. If you are interested in the hobby as an ongoing adventure then a good DSP is the way to go, invest in one and you can save a fortune if and when you want to change speakers. If you aren't interested in spending a lot of time and you just want a set it and forget it system, passive might be easier and cheaper.

Active setups become much cheaper if you intend to experiment with different equipment, passive setups are cheaper up front, but if you intend to change things out more than a couple of times you'll have spent much more than you needed to. 

There are a lot of places to get amazing speakers. You can get speakers that are much better than pre-built component sets for much less money.


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## Victor_inox (Apr 27, 2012)

fulletal7777 said:


> ok i know time alignment, but what is phaze? and as far as eq goes, would i be able to adjust it from my hu? so a dsp is basically just a badass active crossover?


You can force yourself to believe that they are the same but they don`t
you can get a HU with build in DSP or use stand alone unit.


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## Victor_inox (Apr 27, 2012)

gijoe said:


> A passive crossover (little box that you wire your mid and tweet to) is built up of discrete components (resistors, capacitors, etc.) a single full range signal goes into the crossover and the crossover splits the frequencies to each speaker. Because the passive crossover is built from discrete components the frequencies and slopes are set in stone, you may be able to attenuate things, but usually that's about it. The problem with this is that in a car the mounting locations vary dramatically from car to car and the crossover frequencies and slopes may not be ideal for your particular acoustic environment.
> 
> A DSP does the same thing and more, it usually adds many features like time alignment and EQ to further customize the sound, plus the crossover frequencies and slopes are variable, so you can adjust them to fit your environment, so you are no longer stuck with the passives that may or may not be ideal for your car.
> 
> ...


He was talking about active crossovers, with adjustable slopes and crossover points.


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## gijoe (Mar 25, 2008)

Look up phase, I'm sure there are some good animations to show how sound waves interfere with one another. Basically, picture two sine waves that move toward each other and eventually collide. If the high part of one wave collides with the high part of the other wave that is constructive interference and the waves combine. When the high part collides with the low part that is destructive interference and the waves still combine, but this time the high and low sum to zero. So, frequencies that are in phase will add and become louder than each wave would be individually, and waves that are out of phase cancel each other and the perceivable sound is nothing.


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## gijoe (Mar 25, 2008)

Victor_inox said:


> He was talking about active crossovers, with adjustable slopes and crossover points.


Man, after the Ferguson thread you're watching me like a hawk! You're right though, obviously I wasn't careful when I read it.


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## fulletal7777 (Jun 11, 2014)

gijoe said:


> A passive crossover (little box that you wire your mid and tweet to) is built up of discrete components (resistors, capacitors, etc.) a single full range signal goes into the crossover and the crossover splits the frequencies to each speaker. Because the passive crossover is built from discrete components the frequencies and slopes are set in stone, you may be able to attenuate things, but usually that's about it. The problem with this is that in a car the mounting locations vary dramatically from car to car and the crossover frequencies and slopes may not be ideal for your particular acoustic environment.
> 
> A DSP does the same thing and more, it usually adds many features like time alignment and EQ to further customize the sound, plus the crossover frequencies and slopes are variable, so you can adjust them to fit your environment, so you are no longer stuck with the passives that may or may not be ideal for your car.
> 
> ...


damnat, should of gone active... oh well, live and learn lol


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## gijoe (Mar 25, 2008)

As Victor pointed out, I misread your title and thought you were asking about passive vs. DSP.


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## fulletal7777 (Jun 11, 2014)

gijoe said:


> Man, after the Ferguson thread you're watching me like a hawk! You're right though, obviously I wasn't careful when I read it.


you gave great advice either way 

so for example, i have 2 10 inch subs and an id xs57 comp set of speakers. would getting one of the active crossovers from here be worth it to me?http://www.diymobileaudio.com/forum...19-random-cheap-stuff-laying-around-sale.html

and another question, hypothetically speaking if i had just a sub (no aftermarket speakers/etc), would getting an active crossover benefit? because technically there no other speakers the separate the frequencies with


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## gijoe (Mar 25, 2008)

I think the biggest question is whether or not you want to pursue this as a hobby. If you want a nice stereo that you never have to mess with again and that will stay until you get a new car, then probably not. But, if you really want to spend time learning, installing, tuning, uninstalling, reinstalling, retuning... then yes a good active crossover is great. If that's the case then I would do plenty of research to determine which crossover or DSP will be best for you. A lot of the stuff that gets recommended here is serious level equipment, it isn't cheap, but in the right hands you can have a truly amazing stereo system. Honestly, most people don't need that much processing unless they really enjoy the hobby. 

I fiddle with my settings at least once a week, sometimes I make significant changes, other times I just explore different ideas, I love doing this, but if you don't find a lot of interest in learning about this stuff you can still have an very good stereo that you can enjoy. 

I'm not sure what you're asking in your second question. Do you mean that the subwoofer is the only speaker in the system, or that it's the only aftermarket speaker in the system?


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## SkizeR (Apr 19, 2011)

fulletal7777 said:


> you gave great advice either way
> 
> so for example, i have 2 10 inch subs and an id xs57 comp set of speakers. would getting one of the active crossovers from here be worth it to me?http://www.diymobileaudio.com/forum...19-random-cheap-stuff-laying-around-sale.html
> 
> and another question, hypothetically speaking if i had just a sub (no aftermarket speakers/etc), would getting an active crossover benefit? because technically there no other speakers the separate the frequencies with


only one left is the clarion. just sold the phoenix gold. the clarion is easier to use anyway


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## fulletal7777 (Jun 11, 2014)

gijoe said:


> I think the biggest question is whether or not you want to pursue this as a hobby. If you want a nice stereo that you never have to mess with again and that will stay until you get a new car, then probably not. But, if you really want to spend time learning, installing, tuning, uninstalling, reinstalling, retuning... then yes a good active crossover is great. If that's the case then I would do plenty of research to determine which crossover or DSP will be best for you. A lot of the stuff that gets recommended here is serious level equipment, it isn't cheap, but in the right hands you can have a truly amazing stereo system. Honestly, most people don't need that much processing unless they really enjoy the hobby.
> 
> I fiddle with my settings at least once a week, sometimes I make significant changes, other times I just explore different ideas, I love doing this, but if you don't find a lot of interest in learning about this stuff you can still have an very good stereo that you can enjoy.
> 
> I'm not sure what you're asking in your second question. Do you mean that the subwoofer is the only speaker in the system, or that it's the only aftermarket speaker in the system?


im into it all, so in the future ill probly be upgrading for sure. the only aftermarker


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## Victor_inox (Apr 27, 2012)

gijoe said:


> Man, after the Ferguson thread you're watching me like a hawk! You're right though, obviously I wasn't careful when I read it.


 Really that what you think? If it makes yourself feel important so be it.
i was just helping a fellow to understand the topic.


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## 2DEEP2 (Jul 9, 2007)

There can be a difference between an Active (discrete component) and DSP crossover.

DSP crossovers can differ based on how the crossover filtering is programed.

Look up IIR (Infinite Impulse Response) and FIR (Finite Impulse Response) DSP filters.

IIR filters typically mimic a passive or active filter but provide several frequency points and slopes (orders).

FIR filtering has these advantages over IIR filtering:

1. It can implement linear-phase filtering. This means that the filter has no phase shift across the frequency band. Alternately, the phase can be corrected independently of the amplitude.

2. It can be used to correct frequency-response errors in a loudspeaker to a finer degree of precision than using IIRs.

However, FIRs can be limited in resolution at low frequencies, and the success of applying FIR filters depends greatly on the program that is used to generate the filter coefficients. Usage is generally more complicated and time-consuming than IIR filters.

Active (discrete component) are like passive crossovers but permit several crossover frequency points and normally a one or a few slopes (orders). Based on the slope (order) you have phase shift at the crossover point. Crossover point are normally changed by changing a resistor network. Audio Control created a hybrid, a digitally controlled active (discrete component) crossover. 

Active (discrete component) crossovers are included with many amps. Active can also be a stand alone like a DSP. A few amps have DSP as an amp feature.


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## Alrojoca (Oct 5, 2012)

The way I understand the differences may or may not confuse others.

To me an active crossover is a crossover that has the ability to filter frequencies before they are amplified. I could be analog dials or digital, some may include a combination of features, in most cases these have a high pass and an low pass at least for 2 channels, sometimes it is included in the sub section sometimes they have limitations. 

A DSP, Digital sound processor, to me it should have wide range and selection of frequencies including HP,LP for the full range channels and the sub channels, some mono amps have a subsonic filter, it is basically a band pass or a HP/LP , and most HU's have the sub phase reverse 180 degrees or simply called polarity.

A good DSP is an active xover and will also have, at least 16 Eq bands per channel, a wide range of frequency settings in 5 or 10 hz increments, HP, LP (band pass) Digital Time alignment, and at least 3 or 4 slopes from 6db, 12 db, 18db and 24 db, they will also have individual channel output level to balance the output from each driver. Can get inputs from 4-6 channels and they will always convert them to 8 channels, some just take 2 channels to make 8 channels, 8 channels give you the ability to have a 3 way front and sub system, or a 2 way front sub and rear speakers if you wish to do that. 

Maybe I am forgetting something else  but that should be enough to help anyone get an idea of what good sound processor should have.


Some of the built in DSP's in some HU's do the job well but honestly, they will lack either a band pass in the sub section, they will have only 5 or 9 bands eq for all the drivers or have some limitation, unless you get a $1500, 8 ch head unit like the one Skizer has , that thing has everything you need to play and tune and adjust all you want and need.


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## fulletal7777 (Jun 11, 2014)

Where would a DSP go? After the amp?


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## Kriszilla (Jul 1, 2013)

Source (deck) -> DSP -> Amp(s)


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## whaler (Aug 19, 2014)

this may help you a bunch... Happy reading!

Basic Car Audio Electronics


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## ZAKOH (Nov 26, 2010)

Active crossover is one of the many things that a DSP can do. In theory, an active crossover can be provided by an analog signal processor, but these days those are rare and DSP is the way to go.


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## fulletal7777 (Jun 11, 2014)

Kriszilla said:


> Source (deck) -> DSP -> Amp(s)


Wouldn't it make more sense to go after the amp? For example, a 4 channel amp with mid and tweeters hooked up. What's the point of splitting the signal BEFORE it gets to the amp? I would think it gets hooked up between the speakers and the amp.


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## Alrojoca (Oct 5, 2012)

When using a DSP, both HU and amp, should be set to full pass or all filtering defeated to just amplify the signal from the DSP


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## SkizeR (Apr 19, 2011)

fulletal7777 said:


> Wouldn't it make more sense to go after the amp? For example, a 4 channel amp with mid and tweeters hooked up. What's the point of splitting the signal BEFORE it gets to the amp? I would think it gets hooked up between the speakers and the amp.


no. that would be a passive crossover. the short difference between an active and passive crossover is an active crossover manipulates the signal before its amplified, and a passive manipulates it after its amplified.


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## fulletal7777 (Jun 11, 2014)

SkizeR said:


> no. that would be a passive crossover. the short difference between an active and passive crossover is an active crossover manipulates the signal before its amplified, and a passive manipulates it after its amplified.


so how does the amplifier know how to send which frequency to which speaker? it seems to me that the dps separates the frequency, so it sounds like the signal would merge back together when it hits the amp lol im pretty sure this is something i would understand better if i were actually putting it all together


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## Kriszilla (Jul 1, 2013)

Think of it the DSP as a distribution center. The example here is my system, with two P900.4's and one P1000.1's for the amps, 7 speakers total:

The DSP gets the incoming full range signal from my deck and it is going to split it up for me. It's going to say:
"P900.4 #1, on Bridged channel one, here's the processed (EQ, T/A) left signal, from 50 to 315Hz"
"P900.4 #1, on Bridged channel two, here's the processed right signal, from 50 to 315Hz"
"P900.4 #2, on channel one, here's the processed left signal, from 350Hz to 8KHz"

And so on....

The signal isn't going to merge back together because you're sending separate data to each amp channel. The amp can only amplify what it is given. It's not going to add what isn't there.

The DSP has to go before the amp(s) because it's the big brain deciding what signal needs to go to which speakers, and it's a hell of a lot easier to apply that processing before the amplifiers than to try to manipulate the signal after amplification.


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## yogegoy (Feb 11, 2011)

Bit One choice of input signal to use









Other input options

















The output sources that goes to each amp's input signal


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## fulletal7777 (Jun 11, 2014)

Kriszilla said:


> Think of it the DSP as a distribution center. The example here is my system, with two P900.4's and one P1000.1's for the amps, 7 speakers total:
> 
> The DSP gets the incoming full range signal from my deck and it is going to split it up for me. It's going to say:
> "P900.4 #1, on Bridged channel one, here's the processed (EQ, T/A) left signal, from 50 to 315Hz"
> ...


So what about when it gets to the amp? Let's say you've got a mid and a tweeter hooked up to one of those speakers, would you only want part of that frequency going to the mod and part of it going to the tweeters? Yet your sending the whole frequency to one amp, which will then send all that to both speakers?


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## yogegoy (Feb 11, 2011)

fulletal7777 said:


> So what about when it gets to the amp? Let's say you've got a mid and a tweeter hooked up to one of those speakers, would you only want part of that frequency going to the mod and part of it going to the tweeters? Yet your sending the whole frequency to one amp, which will then send all that to both speakers?


On the Bit One you have a choice of going active on each speaker or use a passive x-over to combine the Hi and the Mids for that specific channel since it only allows 8 channels to be used. So allocation is essential on how you configure your set up.


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## yogegoy (Feb 11, 2011)




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## yogegoy (Feb 11, 2011)

You can download the Audison Bit One manual Bit One Users Manual from that link. Everything would be explained to you, just a little research.


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## LumbermanSVO (Nov 11, 2009)

The full range signal goes in the DSP, then the DSP splits it up, EQ's it, delays it and so on. So for a typical 2-way + sub setup it'll look like this:

Head unit Right out -----> DSP Right in
Head unit Left out -----> DSP Left in

DSP Channel 1 out -----> amp channel 1 -----> left tweeter
DSP Channel 2 out -----> amp channel 2 -----> right tweeter
DSP Channel 3 out -----> amp channel 3 -----> left mid
DSP Channel 4 out -----> amp channel 4 -----> right mid
DSP Channel 5 out -----> amp channel 5 -----> sub

The amp channels ONLY amplify the signal given to them and don't combine the signal from other channels. Knowing that, you can see that channel 1 will ONLY be amplifying the tweeter signal, and the tweeter will not be getting any mid or sub signals.


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## Kriszilla (Jul 1, 2013)

fulletal7777 said:


> So what about when it gets to the amp? Let's say you've got a mid and a tweeter hooked up to one of those speakers, would you only want part of that frequency going to the mod and part of it going to the tweeters? Yet your sending the whole frequency to one amp, which will then send all that to both speakers?


In an active setup with a DSP, you're not using the passive crossover boxes. You'd have the mid connected to one amp channel and the tweeter connected to another amp channel. Each speaker gets its own private amp channel to run on.

So, say you've got a 2-way setup, with mid and tweeter on each side, and a 4-channel amp. You'd be using all 4 channels, 2 for mids, 2 for tweeters.

The DSP would sit before the amp, and send the highs to the tweeters and the lows to the mids so the amp never sees a full signal on any of its channels. Also, if the amp has crossovers built in, you would set them to be disabled since that is being done at the DSP which is your crossover now.


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## fulletal7777 (Jun 11, 2014)

yogegoy said:


> You can download the Audison Bit One manual Bit One Users Manual from that link. Everything would be explained to you, just a little research.


suweet, thanks!


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## fulletal7777 (Jun 11, 2014)

LumbermanSVO said:


> The full range signal goes in the DSP, then the DSP splits it up, EQ's it, delays it and so on. So for a typical 2-way + sub setup it'll look like this:
> 
> Head unit Right out -----> DSP Right in
> Head unit Left out -----> DSP Left in
> ...


ohhhh now i get it! so basically if i wanted to do this with my id xs57's, id have to ditch the passive crossover and connect the tweeters/mid separately straight into the amp. Thats cool, didnt think about that lol


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## fulletal7777 (Jun 11, 2014)

Kriszilla said:


> In an active setup with a DSP, you're not using the passive crossover boxes. You'd have the mid connected to one amp channel and the tweeter connected to another amp channel. Each speaker gets its own private amp channel to run on.
> 
> So, say you've got a 2-way setup, with mid and tweeter on each side, and a 4-channel amp. You'd be using all 4 channels, 2 for mids, 2 for tweeters.
> 
> The DSP would sit before the amp, and send the highs to the tweeters and the lows to the mids so the amp never sees a full signal on any of its channels. Also, if the amp has crossovers built in, you would set them to be disabled since that is being done at the DSP which is your crossover now.


so pissed i learned about this AFTER i bought the xs57 comps -.- would these still do well in an active setup, or is it not the best choice with active crossovers?


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## yogegoy (Feb 11, 2011)

Most DSP's have an 8 channel output, that means you have combination of different options within the 8 channels. My first setup was configured this way....
Ch 1) L hi and mid with pass xover
Ch 2) R hi and mid with pass xover
Ch 3) L mid bass low pass 
Ch 4) R mid bass low pass
Ch 5) L Focal KRX 2 way full range setting
Ch 6) R Focal KRX 2 way full range setting
Ch 7) L Sub low pass
Ch 8) R Sub low pass

New set up:
Ch1) L Hi hi pass
Ch2) R Hi hi pass
Ch3) L Mid band pass
Ch4) R Mid band pass
Ch5) L Mid Bass low pass
Ch6) R Mid Bass low pass
Ch7) Sub Lowpass
Ch8) not used


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## LumbermanSVO (Nov 11, 2009)

fulletal7777 said:


> so pissed i learned about this AFTER i bought the xs57 comps -.- would these still do well in an active setup, or is it not the best choice with active crossovers?


It'll be very overwhelming to start tuning a fully active system from scratch. Since you are so very new to this, I'd recommend keeping the setup as simple as possible. Keeping tuning and tweaking with the simple setup and in the meantime read as much as possible so that when you start upgrading and making your setup more complicated, you'll know what you are doing.


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## SkizeR (Apr 19, 2011)

fulletal7777 said:


> so how does the amplifier know how to send which frequency to which speaker? it seems to me that the dps separates the frequency, so it sounds like the signal would merge back together when it hits the amp lol im pretty sure this is something i would understand better if i were actually putting it all together


thats the point of the crossover. it eliminates certain frequencies before it gets to the amp. if you have an active crossover, each individual speaker has its own channel. since thats the case, theres nowhere for these frequencies to "merge" back together


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## fulletal7777 (Jun 11, 2014)

LumbermanSVO said:


> It'll be very overwhelming to start tuning a fully active system from scratch. Since you are so very new to this, I'd recommend keeping the setup as simple as possible. Keeping tuning and tweaking with the simple setup and in the meantime read as much as possible so that when you start upgrading and making your setup more complicated, you'll know what you are doing.


agreed. i just discovered a youtube channel all about fabrication, so im just gunna live on youtube for the day lol ill probly keep looking at useful channels that relate to car audio


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## SkizeR (Apr 19, 2011)

fulletal7777 said:


> agreed. i just discovered a youtube channel all about fabrication, so im just gunna live on youtube for the day lol ill probly keep looking at useful channels that relate to car audio


You won't find much or anything about crossovers on that channel


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## fulletal7777 (Jun 11, 2014)

SkizeR said:


> You won't find much or anything about crossovers on that channel


yeah i know, just general audio stuff lol wasnt quite sure what to do with my false wall after i get it made, so thats my learning goal for today lol random question, but ive got a router and ive learned that i REALLY need a table, any idea a good one to get and where to get it?


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## Alrojoca (Oct 5, 2012)

What head unit are you using or plan to use?


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## fulletal7777 (Jun 11, 2014)

Alrojoca said:


> What head unit are you using or plan to use?


Nexus 7 lol


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## Alrojoca (Oct 5, 2012)

fulletal7777 said:


> Nexus 7 lol


Many, use tablets, you may need a DA converter or AD converter, or maybe connect it through the USB or maybe simply through BT with a 6 ch HU if want a basic 2 way front and sub.

An HU gives you more options, you can use up to 32gb flash drives to play music or can integrate with some apps you have on the tablet


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## fulletal7777 (Jun 11, 2014)

Alrojoca said:


> Many, use tablets, you may need a DA converter or AD converter, or maybe connect it through the USB or maybe simply through BT with a 6 ch HU if want a basic 2 way front and sub.
> 
> An HU gives you more options, you can use up to 32gb flash drives to play music or can integrate with some apps you have on the tablet


yeah, i made a thread a while back about all of it, im pretty sure i got a list of everything ill need. Itl be around $250 for everything to get it put in


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## Kriszilla (Jul 1, 2013)

fulletal7777 said:


> Nexus 7 lol


At your skill level, the JBL MS-8 would be my pick for your DSP. It's almost foolproof, and the autotune works really well. It also has a 15W/channel amp built in which would be great for running a set of tweeters.

You can find them used in the $300-350 range, but emoon3 has a used one in the classifieds right now for $275 that I'd highly suggest. This will also give you volume control via the remote control. 

If you really want to learn how to tune, the Precision Power DSP-88R would be a fantastic choice at $220-ish, and comes with a wired remote to control volume, switch profiles, and select different sources. However, I'd recommend that you also pick up the UMIK-1 microphone from Cross Spectrum Labs, a laptop, and a free copy of Room EQ Wizard (REW) so that you can learn what you need to tune.

Either way, with the Nexus 7, a lot of people use an outboard USB DAC which will give you the clearest signal to your system.


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## fulletal7777 (Jun 11, 2014)

Kriszilla said:


> At your skill level, the JBL MS-8 would be my pick for your DSP. It's almost foolproof, and the autotune works really well. It also has a 15W/channel amp built in which would be great for running a set of tweeters.
> 
> You can find them used in the $300-350 range, but emoon3 has a used one in the classifieds right now for $275 that I'd highly suggest. This will also give you volume control via the remote control.
> 
> ...


I do plan on getting an ms-8 eventually. But I honestly just want to have a radio again lol so I'm just cutting it here and buying the rest of the stuff I need (nexus stuff and sound dampening)


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## Dohlo (Mar 24, 2014)

Kriszilla said:


> In an active setup with a DSP, you're not using the passive crossover boxes. You'd have the mid connected to one amp channel and the tweeter connected to another amp channel. Each speaker gets its own private amp channel to run on.
> 
> So, say you've got a 2-way setup, with mid and tweeter on each side, and a 4-channel amp. You'd be using all 4 channels, 2 for mids, 2 for tweeters.
> 
> The DSP would sit before the amp, and send the highs to the tweeters and the lows to the mids so the amp never sees a full signal on any of its channels. Also, if the amp has crossovers built in, you would set them to be disabled since that is being done at the DSP which is your crossover now.


I'm going to chime in on this since I'm a bit curious about active set ups and might do one in my second vehicle. 

Let's say to keep it simple, someone wants to run a HU that is capable of attenuating certain frequencies to certain channels (ie, running a deck with separate F/R/SW x-overs and not much other than a built in 7-10 band EQ) would this be enough to bypass a DSP if you're running each channel as a mid/tweet channel while rear speakers are off deck power? You technically could set the x-overs to cut certain frequencies from each channel, or at least set the base frequency that you don't want that channel to go below. I get that you can't set the max frequency per channel, but providing the amp, IE something like the JL xd700/5v2, that's capable of running HP/BP filters on the first 4 channels while leaving the SW channel as just that, can you successfully have an active system set up in this way? Or do you absolutely need a DSP and/or deck that's running dedicated low/mid/high outputs? Only reason I ask is because I'm currently running the JL in a standard system running coax's in another vehicle, but it appears it could be set up to run an active front stage if desired. And it's quite a savage little amp IMO, so I figure it's a good starting point if I decide to go with an active front stage. 

Sorry to hijack the thread OP, but there's plenty of good info being passed around and I thought I'd join in


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## BlueGhost (Jul 28, 2014)

Dohlo said:


> I'm going to chime in on this since I'm a bit curious about active set ups and might do one in my second vehicle.
> 
> Let's say to keep it simple, someone wants to run a HU that is capable of attenuating certain frequencies to certain channels (ie, running a deck with separate F/R/SW x-overs and not much other than a built in 7-10 band EQ) would this be enough to bypass a DSP if you're running each channel as a mid/tweet channel while rear speakers are off deck power? You technically could set the x-overs to cut certain frequencies from each channel, or at least set the base frequency that you don't want that channel to go below. I get that you can't set the max frequency per channel, but providing the amp, IE something like the JL xd700/5v2, that's capable of running HP/BP filters on the first 4 channels while leaving the SW channel as just that, can you successfully have an active system set up in this way? Or do you absolutely need a DSP and/or deck that's running dedicated low/mid/high outputs? Only reason I ask is because I'm currently running the JL in a standard system running coax's in another vehicle, but it appears it could be set up to run an active front stage if desired. And it's quite a savage little amp IMO, so I figure it's a good starting point if I decide to go with an active front stage.
> 
> Sorry to hijack the thread OP, but there's plenty of good info being passed around and I thought I'd join in


I have a JL xd700/5 and am doing just what you described. I have a pair of 10's on the sub channel, and a 5.25 component set running active on the other 4 channels. I ditched the passive crossover that came with the components and am using the amps crossovers for the mid and tweeter.

I don't have a traditional head unit. I'm using a car pc, feeding two channel audio into the amp via an USB DAC. In my case I'm also using the amp remote knob for full system volume control, another nice feature the xd has. I started off with the amp bridged and using passive crossovers then moved to active. It made a noticeable difference in tuning, being able to dial in the tweeter levels is worth it alone.

You will get more tuning options with a DSP, variable slopes for your crossovers, equalization, and time alignment, but if you already have the amp its free to experiment.


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## Dohlo (Mar 24, 2014)

BlueGhost said:


> I have a JL xd700/5 and am doing just what you described. I have a pair of 10's on the sub channel, and a 5.25 component set running active on the other 4 channels. I ditched the passive crossover that came with the components and am using the amps crossovers for the mid and tweeter.
> 
> I don't have a traditional head unit. I'm using a car pc, feeding two channel audio into the amp via an USB DAC. In my case I'm also using the amp remote knob for full system volume control, another nice feature the xd has. I started off with the amp bridged and using passive crossovers then moved to active. It made a noticeable difference in tuning, being able to dial in the tweeter levels is worth it alone.
> 
> You will get more tuning options with a DSP, variable slopes for your crossovers, equalization, and time alignment, but if you already have the amp its free to experiment.


Well the amp is in a different vehicle and it's staying there, I just figured since I have experience with it and know what to expect out of it, it would be a great base to start with a new one to build an active system in my Honda. 

With a good deck, I could still mess with time alignment and crossovers to an extent, but I realize it wouldn't do nearly everything a true separate DSP could. I just figured since I know the 700/5 is capable of running active, why not start there  

It's a solid little amp for sure and it's great that it has so many different options as far as set up and what type of system it's running


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