Hi folks,

I'm getting a sub, this one in fact:

http://www.amazon.com/Pioneer-TS-SWX251-Subwoofer-Enclosure-Watts/dp/B004HW6F9M/ref=lh_ni_t

and as such, need to get it some juice. At some point I also intend to replace the 6x9's, and perhaps the factory amp under the driver seat. I'm just thinking out loud here, but . . . do you think it might make sense just to get a really good multi-channel amp, e.g., 4-channel+, and replace the driver seat amp w/ something that can power my 6x9's AND sub, all in one device?

Further, if I were to use one Über amp, does the factory amp's hot/ground have a sufficiently robust connection to the electrical system to power a more capable amp at that location, or will I have to, or should I, run a new line to the battery somehow?

The sub is likely to be positioned directly behind the driver's seat, so it'll be very close to the driver, and relatively close to the passenger. I'm not out to conquer Poland with my bass, just looking to round out the system.

If anyone has some advice for me, I'd appreciate it very much.

Don't buy those prefab subs, they are terrible. That thing won't take more than 200watts RMS, I dont care if it says that it will hit a 800 watt max.

Anyway, back to your question, getting a 4+1 amp isn't a bad idea. You would use it to power the front mid and tweeter, and then the back two speakers. You would need a dedicated amp for either the front 6x9s or the sub, you could not put both on a mono channel.

For your sub box I would grab one of these:
http://www.sonicelectronix.com/item_29893_RE-Audio-UB-10B-Jam-Box.html
With one of these
http://www.sonicelectronix.com/item_27314_RE-Audio-SEX10D4.html

It will be pretty darn loud.
This would be a good "uber" amp to wire up your speakers and the sub
http://www.sonicelectronix.com/item_23827_Hifonics-Zeus-ZXi60.4-1K.html

and you could use this
http://www.sonicelectronix.com/item_22698_Hifonics-HFi100.2-HFi-100.2.html
to power the 6x9s

I appreciate your advice on the sub -- however, I'm well decided on a slim, out-of-the-way sub that will fit in the space right behind the driver seat, which will allow passengers in the back, uncomfortable though it might be, to rest their feat on top of the subwoofer, as they sit facing forward. The Pioneer is a set-it-and-forget-it solution insofar as subwoofer placement is concerned, and I'm sure it's good enough for my needs. I haul around large objects quite often, such as large TVs, home theater receivers, speakers, etc., and can't be hassled to move the subwoofer around. The Pioneer TS-SW251 isn't negotiable. ;) But thanks for watching out for me.

200 watts nominal power on the sub, does this change the equation any regarding which amp I should get? I'm not looking to spend a lot of money, given that I'm really not all that concerned about bass. Just a gentle rounding-out of the frequency response of the entire audio system is all I'm after. The 6x9's almost do that already for me. Is there an all-in-one amp that might fit the area/bill$$?

You can do a 3 channel amp that you can wire to the front speakers and the sub. Let me do some research....

http://www.sonicelectronix.com/item_11594_Boss-CX1800.html

This would be perfect for some loud speakers, and is matched perfectly to your sub

http://www.sonicelectronix.com/item_26584_DLS-CAT-31.html

This is more expensive for only 3 channels, but I would trust DLS over BOSS

http://www.sonicelectronix.com/item_34760_Rockford-Fosgate-R600-5.html

This is the cheapest they have for a truly brand name amp that fits your requirements. The 4 channels are not that powerful, but it should work well to not overpower your sub. I think this would be the best best, and won't break the bank.

Thank you, emrules & Nick! :bow:

I'll try to digest this presently.

Wait wait wait don't you DARE BUY BOSS AUDIO CRAPP!!!!!!!!!!!!!!!!!!!!!!!!
I can see trhe argument for the crappy shallow mount sub even though I disagree with it and think its going to prevent you from being able to adjust your seats and probably going to rattle like a mofo. But dont you DARE buy a crappy amp that is a mistake I have madde time and time again trying to save money. Spend the money, it'll save headache in the long run.
The minimum I would recommend is the http://www.sonicelectronix.com/item_34760_Rockford-Fosgate-R600-5.html
rockford amp he had suggested. Even though the Prime amps kinda suck.

Then for the doors you STILL need a dedicated amp.
http://www.sonicelectronix.com/item_17366_Rockford-Fosgate-PRIME-R150-2.html
You can match it up with one of these I suppose, but ideally you want MORE POWER to the 6x9s than to the 4"ers and the rear 6.5"ers
so that again brings me to this amp
http://www.sonicelectronix.com/item_22698_Hifonics-HFi100.2-HFi-100.2.html
which is great bang for buck from a good company

Thank you again for your generous help, Nick.

I swapped out the stock head unit, for a Pioneer AVH-P3300BT, isn't there enough amp in that to power the smaller speakers? Speaking of which, are my 6x9's now getting two amplifier stages, i.e., Pioneer sending out an amplified signal + under-seat amp? I'm using a metra wiring harness which made things really simple for me, but . . . I'm not precisely clear about what is, in-fact, going on. I will dedicate the time tonight to figure that out.

No definitely not. It's still only 15 watts a channel. If your goal is to clean up the sound even further you need an amp. At 55watts/ch you will be able to get it a bit louder, but more importantly it will sound BETTER and more responsive at mid-volume listening levels.
http://www.sonicelectronix.com/item_22700_Hifonics-HFi55.4.html
This would work well for your purposes. You would still need an amp for the 6x9 speakers and the sub. You could get away with 1- 2 channel amp provided you could locate it under the sib box or under the passenger seat.
This would work, because of its small size and high power output
http://www.sonicelectronix.com/item_8893_Rockford-Fosgate-Power-T400-2.html

Might I suggest that you set up your 6x9s and sub now, and worry about amping the speakers later. You will find, though, that when the bass hits nicely the speakers can't keep up.

Just amp your sub package with this: http://www.sonicelectronix.com/item_22381_Pioneer-GM-D7500M.html
Its a perfect match up at 200w/RMS@4ohm

Once you have that set up I highly doubt you'll feel the need to amp your door speakers. You will however want a bigger bass package in the future.

I was never a fan of amps with spade type terminals. They just look cheap.

Oh I love me some spade terminals. A little silver solder and a good heat shrink makes for a very clean install look.

Ordered the Rockford Fosgate Prime R600-5 and the Pioneer TS-SW251 subwoofer, should all be here by the end of the week. I'm so excited!

The amp's dimensions are 17" by 8" by 2.5" high, looks to me just by eyeballing things that it should fit without problem underneath the driver's seat, after I take out the stock amplifier. Keeping in mind that a) the amp is pretty moderate as far as power goes, b) I'm not a look-at-me, self-praising braggart out to be heard from a mile away, and c) have pretty sensitive ears that can't tolerate loud music, then should I replace the stock power source supplying the stock head unit, or just rely on the built-in wiring/power source? If I do replace it, how tough is that, and do I really have to use wire as thick as my . . . . or can I get by without ill-effect and use something more moderate like 8, 10, or 12?

The headunit's power source is fine. I'm use an powerpack and i havent blown the fuse. Anyone who tells you otherwise is greatly exaggerating. As for rewiring the speakers, alls you need is 16 gauge. For the sub I would use 14 guage. Dont forget, you need spade connectors for all your wiring on the R600, and I suppose you are just bypassing the 6x9s for now?

Ok wait I'm lost here. You bought a 5 channel amp to power 1 subwoofer? Generally people amp their subs with a mono-block, and use a multi-channel for the rest of their speakers that have been matched for power and resistance. Using a multi-channel for all of your needs makes its near impossible to properly set gains and crossovers.

And you don't NEED spade connectors, you can get away with bare wire in those terminals.

Why not just get a nice box to put in the hatch? For the times you need the hatch space, you can simply take the sub out since its not a permanent fixture. I like that idea instead of occupying the rear seat area.

Ok wait I'm lost here. You bought a 5 channel amp to power 1 subwoofer? Generally people amp their subs with a mono-block, and use a multi-channel for the rest of their speakers that have been matched for power and resistance. Using a multi-channel for all of your needs makes its near impossible to properly set gains and crossovers.

The 5-channel amp, as far as I can tell, allows the channels to be controlled independently.

Why not just get a nice box to put in the hatch? For the times you need the hatch space, you can simply take the sub out since its not a permanent fixture. I like that idea instead of occupying the rear seat area.

I've spoken to this already.

The headunit's power source is fine. I'm use an powerpack and i havent blown the fuse. Anyone who tells you otherwise is greatly exaggerating. As for rewiring the speakers, alls you need is 16 gauge. For the sub I would use 14 guage. Dont forget, you need spade connectors for all your wiring on the R600, and I suppose you are just bypassing the 6x9s for now?

Hello again Nick,

When you say head unit's power source, do you mean the amp-under-driver-seat's power source? That's what I was asking about. Do they both go through the same exact path to the battery, through the same fuse? Is that what you're alluding to, or did you think I was talking about the head unit, and not the amp as an independent entity?

The gauge I was referring to is the source of electricity to the amp under the driver's seat. That source will be get a new workout when I install the new amp, hence my question.

4 gauge ground and power to the fosgate amp. If you're only going to utilize minimum power from it you can maybe skimp to 6 but I would go with what the manufacturer recommends.

Perhaps you should have reconsidered the type of vehicle for your needs if you are going to haul around stuff constantly.

He moves tv's and electronics, not bricks and lumber. The tC was probably a sensible option aesthetically and financially, providing the cargo room needed in a sporty comfortable package with good fuel economy.

You could sell these things quite effectively, Rotz. :clap:

4 gauge does look about right. According to the charts and equations I've found, in the most extreme and rare circumstance for my setup, we'll say 30 amps draw/12v/15 feet, a quite tolerable 2% maximum voltage drop. In most cases it'll be within 1% of spec.

Yea id rather use a truck for hauling TV's and electronics. The TC isn't a truck.

This is an off-topic, unnecessary and frankly obnoxious diversion, oblivionlord. Let's take it to PM from here.

Hello again Nick,

When you say head unit's power source, do you mean the amp-under-driver-seat's power source? That's what I was asking about. Do they both go through the same exact path to the battery, through the same fuse? Is that what you're alluding to, or did you think I was talking about the head unit, and not the amp as an independent entity?

The gauge I was referring to is the source of electricity to the amp under the driver's seat. That source will be get a new workout when I install the new amp, hence my question.

The amp under the driver seat is probably on the same circuit as the HU, yeah. I can't be certain but I think it would be odd if Toyota made an entirely separate circuit for a tiny little amp in a econobox. In either case, you can't DREAM of using that power source for your new amp. Thats MAYBE a 12 guage wire.

You need a minimum of 8guage (but i'd HIGHLY recommend 4 guage) for the amp you purchased. You should buy a GOOD brand like Stinger, Monster Cable, Rockford Fosgate, maybe Tsunami. Not Theinstallbay or other cheapo brands. More money is more copper and not an excessive amount of insulation as to make it look like a smaller guage. You can run it directly from the battery into the cab. I used a grommet on the passenger side of the engine bay in the top corner of the firewall which is very easily accessible inside the car. You could probably ground it on the drive seat bracket but you need to sand it down on the top, the bottom and where it makes contact with the floor in order to get a good ground out of it. and that will require pulling out your seat. Alternatively you can run the ground wire to somewhere else in cab which is connected to the subframe.

Ok wait I'm lost here. You bought a 5 channel amp to power 1 subwoofer? Generally people amp their subs with a mono-block, and use a multi-channel for the rest of their speakers that have been matched for power and resistance. Using a multi-channel for all of your needs makes its near impossible to properly set gains and crossovers.

And you don't NEED spade connectors, you can get away with bare wire in those terminals.
5 channel amps are 4 channel amps with a separate but integrated monoblock amp. Not a center channel or something like in home audio.
And I would like to see you fit 4 guage wire into those terminals without spades. It's not all that easy. I've tried. The speaker wires maybe you could skimp out on I guess but thats very unprofessional.
Why not just get a nice box to put in the hatch? For the times you need the hatch space, you can simply take the sub out since its not a permanent fixture. I like that idea instead of occupying the rear seat area.
I do still agree with this point. I'm still not sure how you are going to adjust your seats with that monstrosity back there. Let alone have people sitting in the back seats comfortably when the floor is jacked up 6 inches higher. Talk about no leg room.
The 5-channel amp, as far as I can tell, allows the channels to be controlled independently.
Yes it can. They make installs much easier and cleaner too.

Looks like I forgot to order RCA cables to connect the head unit to the amp. Should I order anything special or is this identical to home theater (where I'm far more experienced)?

You could use home theater cables o guess buy you'll probably pick up interference if they aren't high quality or twisted pairs. I would suggest buying car audio Eva's to weed out interference

Buy something brand-name and you'll be fine

Being a home theater pro I'll assume you have good stuff laying around. Its the same thing, you'll just have to find a set that's long enough.

The headunit's power source is fine. I'm use an powerpack and i havent blown the fuse. Anyone who tells you otherwise is greatly exaggerating. As for rewiring the speakers, alls you need is 16 gauge. For the sub I would use 14 guage. Dont forget, you need spade connectors for all your wiring on the R600, and I suppose you are just bypassing the 6x9s for now?

I hope you're kidding. I blew the little 5A fuse to the head unit within SECONDS after exposing my 300w sub for the first time to music. I replaced it with a 15A fuse, and the amp was still cutting out because it was starved of power. I was also using 14 gauge wire. The blue power LED on the amp was dimming, and flashing to every beat of the sub.

I finally picked up some 2 gauge copper wire, and ran it straight to the battery through that rubber plug on the passenger side firewall. Installed a twisted RCA cable also, now the sub does not skip a beat! The blue power LED is lit very strongly with absolutely no dimming even during the hardest beats.

I purchased this: http://www.amazon.com/Rockford-Fosgate-R300-12-Subwoofer-Included/dp/B004BYPLNM

It sits behind the seats pretty flush with the slanted rear wall on the box, and is held firmly in place with my cargo net. Takes maybe 2 minutes to unhook, and move the box if I need to haul something huge once in a blue moon, but the whole idea of the OP is to not utilize the cargo space, and go for a permanent install behind the driver's seat.

It's only 300w RMS, but is more than enough power for me. I keep the gain, and bass boost all the way down low, and the remote volume control at 1/2 with the head unit subwoofer setting to "00"

I was driving this chick around once who wanted to hear the sub cranked full blast to LMFAO - Party Rock Anthem, and I had a headache by the time the song was done. I thought my car was going to fall apart, and felt my heart vibrating in my chest. The bass sounded nice and hit pretty damn good, but I won't be doing that again!

200W should be fine for the OP's needs, and might even be fine for my needs also. I heard the Pioneer TS-SWX251 in person at a car audio dealer, and it was vibrating the head units, and whatever else was on the wall when he cranked it, believe it or not!

Anything in the 600w range is if you are having a tailgate party, and want to hear the bass OUTSIDE the vehicle. The tC is so small, you don't need much! I also like to be able to FEEL the road when I'm driving!

Anything in the 600w range is if you are having a tailgate party, and want to hear the bass OUTSIDE the vehicle. The tC is so small, you don't need much! I also like to be able to FEEL the road when I'm driving!

The R300-12 is hardly an efficient solution for 300w RMS considering it's a shallow 12" subwoofer contained in a tiny enclosure which is more than likely not even tuned for any real lowend frequencies in the low 30s. Their website doesn't even give this spec, but only the speaker itself which is sad considering it's a Fosgate. I suppose they wouldn't need to since anyone that's buying such an all in one solution probably doesn't care regardless.

However with a good 200w RMS amp/sub and the right tuned enclosure for the sub... you can most certainly wake up a large neighborhood enough to the point where you will certainly start attracting the eyes of thieves. Furthermore... this can all be obtained at a lesser price than $300.

The R300-12 is hardly an efficient solution for 300w RMS considering it's a shallow 12" subwoofer contained in a tiny enclosure which is more than likely not even tuned for any real lowend frequencies in the low 30s. Their website doesn't even give this spec, but only the speaker itself which is sad considering it's a Fosgate. I suppose they wouldn't need to since anyone that's buying such an all in one solution probably doesn't care regardless.

However with a good 200w RMS amp/sub and the right tuned enclosure for the sub... you can most certainly wake up a large neighborhood enough to the point where you will certainly start attracting the eyes of thieves. Furthermore... this can all be obtained at a lesser price than $300.

Yes, it plays in the low 30s, in fact, it plays base so low, i can feel it, but not hear it. No need for anything lower. I believe the pioneer the OP ordered plays lower frequencies than the fosgate.

Read the owners reviews on these subs. You don't own these subs, you are going by looks, and what's on paper.

I hope you're kidding. I blew the little 5A fuse to the head unit within SECONDS after exposing my 300w sub for the first time to music. I replaced it with a 15A fuse, and the amp was still cutting out because it was starved of power. I was also using 14 gauge wire. The blue power LED on the amp was dimming, and flashing to every beat of the sub.

I finally picked up some 2 gauge copper wire, and ran it straight to the battery through that rubber plug on the passenger side firewall. Installed a twisted RCA cable also, now the sub does not skip a beat! The blue power LED is lit very strongly with absolutely no dimming even during the hardest beats.
You realize of course i was talking about THE HEAD UNIT'S POWER SOURCE? Not the subwoofer amp's. I'm sorry if there was any confusion. I was also talking about wiring 14guage from the VOICE COILS to the AMPLIFIER and not the amplifier to the battery. That's something you did not need to wire.



Anythig in the 600w range is if you are having a tailgate party, and want to hear the bass OUTSIDE the vehicle. The tC is so small, you don't need much! I also like to be able to FEEL the road when I'm driving!

I disagree. 500-600 watts is optimal for "party music" like rap, r&b ect. You don't need to crank it--I often don't have it up more than 1/4 power but the fact that the power potential is there is nice when you are in the mood to just drown out the world. Not to mention that it sounds "cleaner" at lower dBs than a smaller amp would. For instance, I'm sure my system would sound "better" than your prefab system would at the same volume level, especially as it gets towards 3/4 gain on your amp remote.


The R300-12 is hardly an efficient solution for 300w RMS considering it's a shallow 12" subwoofer contained in a tiny enclosure which is more than likely not even tuned for any real lowend frequencies in the low 30s. Their website doesn't even give this spec, but only the speaker itself which is sad considering it's a Fosgate. I suppose they wouldn't need to since anyone that's buying such an all in one solution probably doesn't care regardless.

However with a good 200w RMS amp/sub and the right tuned enclosure for the sub... you can most certainly wake up a large neighborhood enough to the point where you will certainly start attracting the eyes of thieves. Furthermore... this can all be obtained at a lesser price than $300.

I completely agree with you, prefab units like that hardly ever sound very good. They are more much "muddy" than a similarly priced sub/amp/sealed enclosure would.

Yes, it plays in the low 30s, in fact, it plays base so low, i can feel it, but not hear it. No need for anything lower. I believe the pioneer the OP ordered plays lower frequencies than the fosgate.

Read the owners reviews on these subs. You don't own these subs, you are going by looks, and what's on paper.

Im damn sure you are hearing what you want to hear. Tiny little box like that isnt going to get lower than high 30s. Also owners manual doesn't say what the box is tuned for which would prove the point of this issue.

Im damn sure you are hearing what you want to hear. Tiny little box like that isnt going to get lower than high 30s. Also owners manual doesn't say what the box is tuned for which would prove the point of this issue.

You don't tune sealed boxes. Sealed boxes provide a wide, flat frequency reproduction. Depending on the power and type of sub, a 2cube sealed box can extend from 30-100 hertz easily. Increasing cubic volume only eliminates acoustic suspension and basically makes the sub behave like a free air mount, removing large chunks of low and high end response. The R300 is a single Fosgate prime 12" sub in a 2cube sealed box powered at 300watts RMS. Thats enough to provide the 28-90hz response that Rockford claims. Using the provided 45hz bass boost thats included will get you some nice sound, while not winning any SPL competitions.

You don't tune sealed boxes. Sealed boxes provide a wide, flat frequency reproduction. Depending on the power and type of sub, a 2cube sealed box can extend from 30-100 hertz easily. Increasing cubic volume only eliminates acoustic suspension and basically makes the sub behave like a free air mount, removing large chunks of low and high end response. The R300 is a single Fosgate prime 12" sub in a 2cube sealed box powered at 300watts RMS. Thats enough to provide the 28-90hz response that Rockford claims. Using the provided 45hz bass boost thats included will get you some nice sound, while not winning any SPL competitions.

There is no way that sub hits 28Hz. To you it may not matter but there is absolutely no way that a 300 watt amp can make a 12" sub hit that low in a 2' cubed box, at least not at detectable levels. No one is talking about winning SPL competitions here. Your system on the other hand would fair quite well in one...

28hz in the lab, sure it can. A detectable level while driving with music at volume, no probably not. But if you wanna get picky there's not really a whole lot of music out there that utilize bass tones that low anyways. :tongue:

I mean really though, its a $200 all in one package.

You don't tune sealed boxes. Sealed boxes provide a wide, flat frequency reproduction. Depending on the power and type of sub, a 2cube sealed box can extend from 30-100 hertz easily. Increasing cubic volume only eliminates acoustic suspension and basically makes the sub behave like a free air mount, removing large chunks of low and high end response. The R300 is a single Fosgate prime 12" sub in a 2cube sealed box powered at 300watts RMS. Thats enough to provide the 28-90hz response that Rockford claims. Using the provided 45hz bass boost thats included will get you some nice sound, while not winning any SPL competitions.


So untrue... in the world of Bass, a sealed box can be tuned in many ways, the shape of the box, the density of the wood (or material used to make it), where the sub is located in the box and ect... Bass works on reflection, not line of sight. It's the whole reason manufactures put specifications for min and max sealed/port enclosure sizes for their speakers.

Acoustics do play a role in tuning a box as well. One box might sound good in one vehicle, but crap in another. Polyfil also slows the sound waves down making the sub sound deeper and louder. If you can get the PERFECT square box, than it would be louder than others, b/c the reflection wave would not cancel out the sub, but amply the sound even bigger.

You can justify the Fosgate all you want. There's no way it's going to hit 28hz.

Just to clarify.. Fosgate doesn't specify the dimensions of the box to be outer or inner. If we use the supplied measurements as outer then...

H14.96" x W20.35" x D11.50" = 3051"
12 x 12 x 12 = 1728
3051" / 1728 = 2.02cu

The inner dimensions will have to be less than 2.02cu depending on the thickness of the wood used.

When is the last time you saw a sealed box shaped like a pyramid made out of birch? They're all basically square, made from MDFB.

Polyfilling a box that is already at the woofers optimal size will only act to make the box seem larger, making it behave like a free air mount.

The R300-12 is loaded with a Prime R1S412 which according to Rockford Fosgate (the guys who make it) requires a minimum .7 cubic feet, or an optimal 1.8 cubic feet of volume. Now the box is probably constructed from 3/4 or 1/2 inch MDF and the speaker itself has a displacement of .101 cubic feet. Calculate that and you'll probably end up with an internal volume of about 1.8 cubic feet.

You can try to justify yourself all you want, but I'll believe one of the most respected vehicle audio companies with over 30 years of experience with some of the most talented designers and technicians in the world. If Fosgate says it will hit 28, it will hit 28.

I suppose you will say it is 28hz even though it's not regardless what marketing they put on the box.

To each his own then