Understanding Active

[Elvenking]

yes, i guess according to dude above, u don't need a bass blockers if u go active, i was mistaken, thanx for the info

Okay...I was getting a bit confused....cool. I had imagined this was being suggested to prevent any accidental active xover adjustment to lower freqs that might harm the tweeter if one wasn't careful. I am about to go active myself with a LJ CX360/4 and a CX360/2 on the bass bridged. Thanks for this thread.

 

[MakkMar10]

See if you have a Audison Bit One DSP you wouldn't have to bother with all that. You'll just use the stereo output of your HU or even a optical if it has one, then plug into the DSP. In the software part to access all that is allowed you assign the 8 channels to their perspective frequencies, like channel 1-2 to highpass, 3-4 to bandpass, 5-6 to lowpass then 7 (for mono) or 7-8 (stereo) subwoofer. You wouldn't need XO at all because it's all provided to you from the hardware of the Bit One. You can have 30+ graphic EQ's in all individual channel for adjustment, delay, TA and two XO formats (Butterworth or ???). That will be the way to go than hooking up passive XO's everywhere or not, tons of options is the point for all this.

This will be my first time with compo, I wan'a keep it simple as possible but not jus plug an play simple. I want to mess around with my speakers a lil bit. But this seems kinda advanced....

 

[Beau M 10+ year member]

This will be my first time with compo, I wan'a keep it simple as possible but not jus plug an play simple. I want to mess around with my speakers a lil bit. But this seems kinda advanced....

Actually its as easy as it gets, and allows you to mess around with your speakers more than any other option.

 

[MakkMar10]

Actually its as easy as it gets, and allows you to mess around with your speakers more than any other option.

It talk'n about using a DSP? Or jus running active n general?

$500? I'd rather get 2 Q4-120 amps, if all it does is give me a channel per speaker.

 

[yogegoy]

You won't get, create, accidentally feed a low frequency signal to your hi's, mids and in between because before the program moves forward during initial installation you'd have to assign what channel is used for. Here is the link so you'd have an idea Audison Bit One. The less you have connected the less noise and everything related to it, simplifies your setup and most important room for other gadget you do't need.

 

[MakkMar10]

You won't get, create, accidentally feed a low frequency signal to your hi's, mids and in between because before the program moves forward during initial installation you'd have to assign what channel is used for. Here is the link so you'd have an idea Audison Bit One. The less you have connected the less noise and everything related to it, simplifies your setup and most important room for other gadget you do't need.

Well if I'm careful I shud jus b able to use the filters on the amp rite? Do I absolutely need a DSP? Tweets are relatively inexpensive so a blow set cud be replaced for $70-100.

 

[BoomTaco64]

if using an active setup why use bass blockers when you have the appropriate equipment to do so. they are unnecessary parts and money wasted. get the correct amps, radio, eq and your good. just make sure you understand what you are going first. as long as you have good eq control on your radio and can go active you do not need the audison parts. make sure your headunit is a really good one for an active setup with a ton of eq controls.

 

[MakkMar10]

if using an active setup why use bass blockers when you have the appropriate equipment to do so. they are unnecessary parts and money wasted. get the correct amps, radio, eq and your good. just make sure you understand what you are going first. as long as you have good eq control on your radio and can go active you do not need the audison parts. make sure your headunit is a really good one for an active setup with a ton of eq controls.

I want the Pioneer avh-x4600bt it has an 8band EQ. Will this work?

 

[Popwarhomie 5,000+ posts]

Get an 80prs. You will be happy you did if your going active. Plus all the other benifits of running an 80prs.

 

[MakkMar10]

Get an 80prs. You will be happy you did if your going active. Plus all the other benifits of running an 80prs.

I need a 2din, do a lot of movie watching. Any suggs?

 

[mlstrass 5,000+ posts]

AQ amp will let you bandpass the mids. If getting the AQ supertweeters they have a cap on them, so you would set those amp channels to FULL.

1 tweeter per 2 mids is really all you need, so 2 tweeters/4mids is what I'd suggest. With PA stuff that will get very loud....

 

[CerwinVega_Fan 10+ year member]

I need a 2din, do a lot of movie watching. Any suggs?

Clarion makes a active capable double din if I'm not mistaken. I forget the model number.

 

[MakkMar10]

Clarion makes a active capable double din if I'm not mistaken. I forget the model number.

Do you kno wat features I would look for to know if an HU is active capable?

 

[MakkMar10]

AQ amp will let you bandpass the mids. If getting the AQ supertweeters they have a cap on them, so you would set those amp channels to FULL.
1 tweeter per 2 mids is really all you need, so 2 tweeters/4mids is what I'd suggest. With PA stuff that will get very loud....

Do you kno if PA tweets are sharp? I'd lik a soft dome tweeter if possible. If there are super tweets tht are not so sharp il look into those.

 

[bbeljefe]

Do you kno wat features I would look for to know if an HU is active capable?

DSP (digital signal processing) is what you're looking for with a head unit that's "active capable" but frankly, any head unit can be used in an active setup. All active means is that each band of frequencies is controlled and powered by separate active crossovers and amplifiers (or amp channels). In home and pro audio, active is normally called biamping, although speakers can be biamped and still be crossed passively.

If your head unit doesn't have the correct crossover options then you need them on your amps. Monoblocks have low pass filters so they're a no brainer but for the separation between midrange and treble, you need an amp(s) that has filters with multipliers and/or bandpass filters.

With multipliers, there is a switch on the amp that multiplies the crossover frequency by a factor of ten. In that case, the options will usually be 50-500Hz or 500-5000Hz depending on the multiplier switch position. With bandpass filters, there are separate high and low pass filters for each pair of channels.

Here's a pretty common setup, since most modern head units with three preamp outputs have built in crossovers:

Head unit low pass is set to 80 Hz. High pass is also set to 80Hz. Subwoofer amp filter is turned off or, turned up all the way so that the head unit controls the crossover point. Midrange amp channel low pass filter would be set to low pass with multiplier engaged and crossover point would be 2500Hz. Tweeter channel filter would be set to high pass with multiplier engaged and crossover point would also be 2500Hz. In this scenario the head unit controls the low frequency cutoff point for the mids and the midrange amp controls their high frequency cutoff point The mids are the only stage requiring a bandpass type filter. Subs and tweets are simply low and high passed, respectively.

As for putting passive filters (bass blockers) on the tweeters, that defeats the purpose of running active on top of possibly introducing phase problems. The reason being is that one of the beauties of active is that you can adjust crossover points and with passive filters on the tweets, you can't.

Another important feature for running active in car audio is time alignment. It's particularly important in vehicles because the tweeter and midbass drivers are often located far apart. You can run active without time alignment but if you do, you run the risk of having your imaging out of whack.. which basically means that you'd be able to hear that the tweets and mids are coming from different locations. That's most noticeable when the mids and tweets are playing at or near the crossover point because they're playing the same frequencies but those frequencies are reaching your ears at slightly different times. This can cause a phase shift that can result in a perceived dip in frequency response as well as some other annoying phenomena. All that said, time alignment isn't just for active setups. It's nice regardless of how your speakers are set up and even if you're running coaxials.

I know that the AVH series of head units from Pioneer have time alignment but you have to buy a microphone from Pioneer in order to run the setup procedure, as it's not manually adjustable. Also, I'm pretty sure the NEX series have DSP and some pretty comprehensive crossover options.