What size amp?

Hello!
Im not running rear fill in my tacoma,Active up front with hertz hi energies with a twk 88,Im using 2 amps...One is a 4 channel and the other is a mono...If i want to run the rears later on do i need to buy a 6 channel?I'm not sure if i can run the rears on deck power since i have the twk 88?

 

I bought an Audio Control 2CH amplifier to do the tweeters up front when I went active. I run the front low, and rear full range from my 5CH. Your system would be more simple if you had a 6CH and a mono, but adding a small 2CH isn't a big deal, except for the added space required.

 

Im running three audio control amps in mine. two 4 channel and one 1 channel. They run active 3 way front, rear fill and a sub.

audiocontrol acm 4.300 - front mids and tweeters
audiocontrol acm 4.300 - front woofers and rear speakers
audiocontrol acm 1.300 - bridged 10 inch subwoofer

They are all powered by a audiocontrol dm-810 10 channel dsp.

Ignore the dust, this picture was taken right after I did a bunch of cutting.

 

I like the extra amp idea. At least that's what I'd consider - another small amp that I could turn on and off to accommodate rear passengers or whatnot. Might come in handy while camping, tailgating, etc. Rear fill is difficult to integrate though, and more often than not will detract from the front seat experience. And I do not believe the TWK88 has the ability to properly integrate rear fill.

Yeah, you probably could use head unit power for the rear, but there are problems there. Since you aren't running it through the outboard processor you have no control over time, frquency, phase, etc on those drivers. You may be able to time align to them with the TWK, but will not be able to tune them beyond your HU's capabilities. You also have the low power output to consider.

IMHO rear fill is a waste of time and resources in a vehicle unless it's to keep rear passengers entertained. But even then I'd want the ability to turn it off. And for me at least it would stay off most of the time. This isn't home theater we're doing here and our processors aren't set up for 5.1, etc where you would use surround speakers. We're mostly playing stereo music, which is intended for 2.x systems and only contains left and right signal information.

 

Thank you all for the information!! I do like the the audio control idea..If i do run rear speakers,I might do that with the audio control...What do you think of the JL RD series amps?I was thinking of the RD 5 channel 75x4 with 500 x1 for the sub,My sub is 500 rms.

 

I personally like to separate the subwoofer amp from the rest of the amps (no 5 channel) That way if I decide to add another subwoofer, or get a more powerful subwoofer, I dont need to replace the whole thing... I can just add a new sub amp by selling the 500 watt and getting a 1000 watt, or adding a matching 500 watt.

I like to try to rely as little as possible on a single point. If the 500 watt section of the 5 channel amp goes out, you need to replace the whole thing, or if a single channel goes out again you replace the whole thing. But if you have separate amps, just replace the broken amp and move on.

 

great point!!

 

That depends on how loud you want it to be. I think 75W for HiEnegy is lowballing it. The woofer alone handles 100W RMS 200W Peak.

The deal on the TWK88 is that it has more ability than what's useful for most people. I'm able to integrate rear fill using time alignment, but only because I have the equipment to measure the delays. I really don't feel like a measuring tape cuts it. If you have the ability, rear speakers simply adds volume to your system. It doesn't pull the audio stage to the back at all, and with the TWK88, you can easily toggle presets and change the delays for when you have passengers.

 

Ok since i got an active system up front with the hertz..What would you use for the tweeters and mid range?I could bridge the amp and it would be 200 watts each side but i would have to use the passive crossovers...I think audio control has a 4 channel 125 watts x4.

 

lc-4.800 will do 125 x 4 to your front stage
lc-1.800 would do 500 x 1 to your sub (4 ohms, 800 at 2 ohms(perfect for adding another sub))
acm 2.300 would do 75 x 2 for your rears and will take up a tiny amount of space.

Keep in mind what the power handling of your speakers are though. If its 125 watts rms for the system, then its probably around 90 for the woofer and 35 for the tweeter. You wont need a huge amp to run them. Trying to push 125 watts into a 35 watt tweeter is going to shorten the life of the speaker pretty quick.

Thats why I went with the smaller acm amps, im running JBL 2 ohm 3 way components, so each speaker can get 75 watts, but they are rated for that.

 

Strongly disagree with this statement, but there's one way to find out

 

I think you would be taking a step back from an active 2-way going back to passives - assuming you had it set up well to begin with. The only thing this is going to get you is louder.

I'm curious though - are you doing this to try and improve something for yourself as the primary driver or are you doing this for passengers. Or just feel like 'upgrading' the audio again?

 

A good, if windy discussion about rear fill

 

I tried your link but that site has obnoxious ads so scrolling through the one-liners to find real content is a chore. You have a TLDR handy? I only made it to page 4 before I couldn't take it anymore.

 

Yeah, you really need to use that site with a PC, logged in, and running some sort of ad blocker. Otherwise it's a miserable experience.

TLDR? Too Long Didn't Read?

 

Yeah

 

I like them a lot personally. You get most of what you get with the XD line, but with a smaller lineup and sacrificed processing features. Underrated like most of JL's stuff. Always great quality and support. I'd use one in a heartbeat if they made what I needed.

Big D Wiz tested the RD100/1 and got good results

 

Naah, I found an extension to shorten the length of the URL but not to compile the text

 

All I got from reading what I did was that there are guys out there that are retarded and are trying to use rear fill as some kind of surround effect, and the argument for front stage only is you get smearing, but I never saw anybody talking about giving it an honest effort and discussing the pros/cons. It seemed like people fell into three categories.

1. "I should hear dialogue from the surrounds! They aren't working!" guy... I've talked to this guy before. He's got a THX setup in his house but doesn't know what THX actually is, and his knowledge of faithful reproduction is completely absent. Never go down the rabbit hole with this guy.

2. "Rear Fill no fucking way!" guy. I get the sense this is a partly bandwagon position too. "The guys I respect have this opinion so it's my opinion as well." All I can say about this is that I feel like there are people out there that cherish an idea where all music is mixed and mastered to be presented to an auditorium audience and that all music is meant to be experienced through some sort of forced audio perspective. I see a lot of tossing out of buzzwords like Haas and FFT or Klippel this and Fletcher Munson that. It's good to understand these things but remember we're talking about two channel audio, it's not being encoded/decoded for spacial reproduction.

3. This is where I am... Two channel, with good time alignment but nothing is perfect. My stereo can be really loud, but tuned well enough that nothing hurts, and the kick drum hits at about waist level a foot in front of me, stuff pans left and right, and the mono stuff lives loosely about where the stereo is mounted and distances can be heard when the mix creates the space. To me the effect is that you are more IN the music space rather than observing it from some distance, and this is my preference when listening to almost all audio. A well tuned, organic sounding system, flaws included, will always sound better to me than a tightly controlled audio laboratory. It just sounds bigger and more intense IMO.

For this reason I am in favor of well done rear fill.

Now back on topic for OP:

If you want to add rear fill, my suggestion is to use your existing 4CH amplifier to run the front woofers and rear speakers, and to get a small 2CH 50-75 W/CH amplifier for the front tweeters. Your tweeters rate at 120W max power, so for 3.5kHz and above that would be more than overkill (this amp needs to be turned down quite a bit). Once it's all hooked up, get the channel balance dialed in and try to get your rear speakers and subwoofer time aligned well enough so you don't hear instruments moving front to back and enjoy.

 

Totally. I just don't think the processor in question here performs the necessary algorithm. Proper rear fill however will be unpleasant for rear seat passengers.