Tri Mode Setup

Hey everyone, New to this forum. I recently purchased a pair of Infinity Kappa 6 x 8" component speakers. I also purchased a Profile Baja BA600 amp off ebay for $35 shipped . I was reading the manual for the amp and I would like to run the speakers in tri-mode with a single JL audio WX10-4 sub. Everything is going into a regular cab ford ranger so I'm limited on space and would like to use only 1 amp. I'm building an enclosure for the sub that will go behind the drivers seat. I'll post designs of that later. The specs on the speakers: http://www.infinitysystems.com/car/products/product_detail.aspx?prod=KAPPA680.9CS&cat=KAP&ser=KAP&Language=ENG&Country=US&Region=USA The specs on the sub: http://www.crutchfield.com/p_13610WX4/JL-Audio-10WX-4.html?tp=111&tab=features_and_specs I've been reading up on passive crossovers but I'm still not sure how I want to run this setup. What are the benefits of 12db vs 6db slopes? I'm still not exactly sure what crossover setup would work best for my setup. Do I even need to use capacitors for the door speakers? I was thinking about buying an 80Hz coil for the sub. What do you guys suggest?

As far as the crosovers go.  I would highly recamend that you run them on all of the speakers in the tri-mode set up.  The benafit of 12db over 6 is that you will loose over 98% power in one octive (an octive being either double, or half the frequency)  with the 12db, while with the 6db it is about half of the. In short, what that means is with an 80hz 12db per octive crossover, that at 160hz the sub is betting roughly 98% less power than it was at 80 hz.  I have never done tri-mode myself, but i have looked into it, and i believe for it to be a useable option, that amp would need to be stable at 2 ohm bridged with the speakers and sub you are running.  i could not find the specs for that amp when i looked it up, but i highly doubt that it is stable at that range.  not a lot of amps are.  most tri mode set ups that i have ever seen use 8ohm speakers, but those 6x8's should be a 4 ohm.  I have also seen it done an 8 ohm sub and 4 ohm speakers, but i am not sure how that worked out.  Like i said i have never done it myself but i would make sure you do your reaserch on this one it is a very uncommon way to do things, and from my understanding it is fairly specific how it needs to be dont to work correctly.  If your entire goal is to run everything on one amp, the easiest way to do it is to buy a nice 4 channel amp.  run your speakers on individual channels using the HPF on the amp, and bridge the last 2 channles on the amp to your sub using the LPF built into the amp. i know a guy who did the tri mode thing on a motorcycle because he had no room for a 4 ch amp, but in a ranger you should have room for a 4 ch amp. If your cousin is such a good installer, and he will install anything for a 6 pack; why are you talking to me?

The amp I have is stable with 4ohm bridged and 2ohm stereo. The speakers are stable @ 2ohm. It's an HA600 there is no BA600. This is a pdf of the manual for the amp: http://www.profileusa.com/manuals/HABajaAmps.pdf I have a profile california amp in my mustang powering 2 RF P2s and it works great. It isn't bridged though. They are out of business now but crutchfield used to sell their products. They are pretty solid. I got the hole tri-mode idea from the manual.

Your purchase price of the Profile amp is about appropriate to its worth.  I suggest you find a nice deal on another two channel amp or class D mono amp to drive your sub, and use the current two channel amp for the pair of speakers.  The amp's specs may suggest that the pair of speakers would be overpowered, but I think it is likely a very good matchup.

As the sub is a single coil 4 ohm, look at the bridged power rating if the (new) amp is two channel, or look at power rating into 4 ohms if the amp is mono.  You will not regret spending a little more for the proper power for your system.

Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

Your speakers are not "stable @ 2ohm"  speakers themselves are not stable at anything.  they are what they are...  Those speakers, are 2 ohms, and the sub is 4 ohm.  in the manual you posted for the amp it says, "CAUTION! In Tri- mode operation, the amplifier must see a 2 Ohm load or higher for the stereo satellites and no lower than 4 Ohms for the subwoofer(s). Any lower than the above mentioned impedance will cause internal damage to the amplifier."  You are within those paramiters so it should be fine.  You will be pushing that amp as hard as it can be pushed safely, according to the manual.  You will need to build, or buy a passive crossover for the sub.  Like you said the capacitor is unnecisary since those infinitys already come with a pair of crossovers that are pretty nice.  since it is a seperate (component set), if you didnt have those crossovers, you would need to build 2 crossovers per pair, a bandpass filter for the mid base driver, and a high pass filter for the tweeter, but as long as you have the ones that came with the speakers you should be fine. If your cousin is such a good installer, and he will install anything for a 6 pack; why are you talking to me?

stevdart wrote: Your purchase price of the Profile amp is about appropriate to its worth.  I suggest you find a nice deal on another two channel amp or class D mono amp to drive your sub, and use the current two channel amp for the pair of speakers.  The amp's specs may suggest that the pair of speakers would be overpowered, but I think it is likely a very good matchup. As the sub is a single coil 4 ohm, look at the bridged power rating if the (new) amp is two channel, or look at power rating into 4 ohms if the amp is mono.  You will not regret spending a little more for the proper power for your system.

Although i did say i believe that TRi-Mode would work with your setup, as long as you do the crossovers.  I agree with Stevdart 100%.

If your cousin is such a good installer, and he will install anything for a 6 pack; why are you talking to me?

I don't think I need that much power. Couldn't I just turn the gain down in order to protect the speakers? I am already running the amp with these speakers and it sounds great, really crisp and clear. Is there something wrong with profile stuff? The amp gets slightly warm to the touch after a typical car ride. My plan is to use this for the infinity components and the JL sub and use the head unit to power my rear speakers(which are pretty much useless in a regular cab truck due to location). If there is too much power going to the speakers would there be a way to limit the power going to them, like a resistor or something? I'm trying to do this on a budget and keep the amp I have. I am no electronics expert. I'm still learning.

Hello Nordo, Tri-mode setup works well when you are using one sub and multiple speakers. I have a motorcycle and had to find a way to power two JBL 4" speakers and a JL 8" W3. I will followup with a specific post for my setup and all the parts. Anyways when doing a trimode setup the amp is playing full range from 18- 20,000 hz ( just a example of full range) When you use Tri-mode the Subwoofer is bridged accross two channels ( thats pos from left speaker output on the amp and neg from the second channel which should be the right speaker) The way you conserve the speakers sound quality and get the most power out of the amp is a filter (choke coil) on the sub pos wire and capacitor as AFdan was describing for the speakers. The signal plays out full range and with a capacitor on the speakers and Choke on the sub they take full advantage of the amps RMS power. Speakers will place load on the amp as the Hz played rises above the range that your capacitors are tuned for then as the Hz drops down the speakers no longer place a load and switches to the Sub Hz range and now it is placing the load on the amp For my setup there are two JBL 4" 2 ohm and 8 ohm for my sub JL W3 8" , between 2 ohm stereo and 8 ohm mono I have a 4 ohm Tri-mode full range.   This is the lowest I recommend Tri-mode and its even pushing the limits based on basic math but works well. My Trimode configuration summarized- A Amp at 4 ohms bridged sees 2 ohm stereo. So with the front dash speakers I start out with 4 Ohm on the amp, then bridged we have 8 ohm on the sub, Now if the amp load is 4 bridged and we parallel 8 ohm sub woofer on it that is 2.667 Ohm bridged. ( that's basic math but tri-mode is easier on the amp when you look at a load of a Sine wave on two filtered frequencies) I only turned my amps gain up to 1/2.   For most amplifiers this is still low but never ever go below 2 Ohm on Tri-mode in any case even when your dont mind risking your amp! 4 Ohm is your perfect goal and your amps happy place. , I have a 120 hz coil for the sub and high pass filters ( capacitors) in line on the speakers. 80 hz is completely fine I just wanted to get a little more sound per watt out of my sub. http://www.bcae1.com/trimodpd.htm    this gives more info on why trimode is easier on the amp and how the power is dissipated based on load. With this setup on my Motorcycle I should have 75 watts to each front speaker and 75 watts for the sub. Given the sub is rated at 100 watts this was a fine starter setup and speakers can play so loud my eyes hurt being 2 ft from them and I still hear music fine until around 60-65 mph Shark outdoor RV and MOtorcycle amp SHKQA1302 220w RMS @ 12V RMS @ 2Ohms 2 x 110w 30 Amp fused thats 360w max based on 12v, or 432w max based on 14.4 charging system which is standard. Realistically Im running the amp at a lower ohm load than I should and you normally would do this with two 4 ohm speakers ( or higher) and a 8 ohm sub for best life of the amp. But I only spent maybe 60 dollars on it and its lasted about 10 months. My advice nordo is to avoid using 2 ohm speaker and 4 ohm sub combo your amp will run hot , but a 4 and 8 ohm or 8 and 8 ohm combination you would be best for a permenant install with Tri-mode. If you can cut it and get me DC power I will mod it.

I am surprised that the manual recommends 2 ohm for speakers and 4 ohm for the sub that would be 1.3 ohms constant load. I know that trimode is a lighter load on the amp but I am surprised it would make that much a difference. Based on your manual its okay to run the setup BUT turn your gain down until you know if its getting very hot or clipping. Your initial tune is important so turn it up gradually 1/8th turns over a few minutes to make sure you don't smell smoke, sub sound clipping or excessive heat.   Remeber for sure not to leave off the filters for the speakers and choke ( coil) for the sub.If you can cut it and get me DC power I will mod it.