xaznperswaesonx

I've searched but havent found the answer. is it safe to connect a subwoofer to the 6x9 lines? i've done it to my integra before it it worked out fine but i used a filter to filter out the higher freq. i know each 6x9 are 4ohms each. Is the stock amp stable at 2ohm mono?

elduderino

It is NOT OK to drive the subs with the stock amp, IMO. I wouldn't chance it, and they would sound like crap too.

It is OK to tap the speaker wires to an aftermarket amp and drive that amp.

Note that those speakers are subs, so they only get bass.

xaznperswaesonx

can you explain why it wouldnt be ok? as i see it .. the stock amp puts out .. what 22rms to each channel including the 6x9 in the back. if you bridge the two 6x9 line together .. it should be ok .. unless the stock amp isnt capable to maintain a 4ohm mono load. since i couldnt find out if the amp can be wired in parallel .. ex .. take the positive lead of the left side and the negative lead of the right side and connet those to the sub.

acuratsx03

dont cheap out on your system!!! if youre gonna do it, do it right so you dont end up paying a lot more for your laziness later

Bass Mechanic

first of all if you bridge that amp it will probly blow the outputs not all amps are designed to be grounded.
2nd there isnt enough power in the stock HU to drive a sub with anough power to make it worthwhile

xaznperswaesonx

lol .. this is for temporary use had an old sub lying around. was looking for more bass until i get a hold of all my goodies.

goodies:
Pioneer 7300 dvd (already have)
MB Quarts PCE216
MB Quarts RCE216
MB QUarts RCE219??? its the 6x9
(2) JL Audio 12" w6v2
JL Audio 300/4 (already Have)
JL AUdio 1000/1

Wires and power cables by monstercable (already have)

had to upgrade a couple of speakers so lol dont have much goodies!

xaznperswaesonx

Care to explain about being grounded BM? I live to learn!

elduderino

Yes, but I am running the risk of A) explaining about boring theory crap, and B) Having somebody go all ballastic and bitch about the answer. But for you the world...

Not sure where you get this "22rms" number??

As you probably read in my OEM amp thread, this thing looks like 2 four-channel amp ICs. Why would we think that it has 22 watts RMS? I have never heard an automotive sub run near hard enough by an amp IC like this.

Well, you can't. This amp is not bridgeable. First, while I don't know this about these ICs, most every "high-power" two-channel audio amp IC is actually two pairs of low-power audio amps, internally bridged. You can't bridge those again.

Secondly, regardless of the internal topology of the IC, this amp is NOT bridgeable.
Until you provide Pioneer technical info that shos that it is, it's not.

It's not.

So you don't know either... was that your real question? Are OEM amps briedgable? As a rule, no. I have never seen an OE amp bridgable. That is a flexibility feature and OE stuff doesn't have any features like that, which cost money. Just doesn't happen.

xaznperswaesonx

great info! .. i'm not the type to bitch specially when someone is schooling me. I'll just poses question for the teacher to answer if i feel something needs more explanation. But thanks for the info. I was awaiting for your answer and BM's specifically before i went ahead and do it. You two seem to be the most knowledge able out of all of us (or so it seems).

elduderino

Not you, x.

Bass Mechanic

sure IC amplifiers such as the one in the TSX arent bridgable because they arent usually AB and they dont have a switching powersupply.

they share common ground usually with that of chassis ground.
you have to have a floating ground in order to bridge an amp.
most amps that are bridgable are able to be bridged because by design their outputs are isolated from each other. it's like having 2 batteries you can wire in series
most amps have you use 1 positive and one negitive output from each channel. they share a reference ground inside the output stage that allows you to sum the outputs into 1 single channel.
you cant do this on a common grounded amplifier because they dont have a power supply with a floating ground. not only that they lack the current capability on an IC and they would easily over heat.
anytime you bridge an amp you increase its current draw through the output stage by a factor of 2 given the same impeadance.

it's simple OHM's law, if you get 2 x the power (watts) with the same resistance (ohms) you have to also send 2x the voltage to the speaker, which also means 2 x the current (amps)
when you bridge an amp all you are really doing is adding the power from 2 channels in series.

i hope that helped more than confuse. sorry it would take a lot more technical explanation and a circuit diagram to explain better.
i am sure you wouldnt want to read it all and i dont feel like typing another novel.

iamhomin

Good info! Thanks!

arizonaalex

Can you tell me more about a floating ground? Is it not the same as just grounding the amp to the frame?

Thanks!

Alex

xaznperswaesonx

info helped alot. understood most of it too. so floating ground represent each channel having its individual ground within the amp? reps is in order!

elduderino

Common-grounded speaker outputs have the + going from the output (usually a cheap radio) to the speaker + terminal, but the - terminal doesn't even have to go directly to the speaker - it's electrically shared with the ground plane of the car. You could just ground the speaker - terminal - it completes the circuit through the car's ground plane.

If you take an old cheap low-power radio and look at the speaker wire outputs, it probably doesn't have speaker (-) wires, but it if does, and you take a voltmeter and measure, the speaker (-) and the radio ground wire are common electrically inside - they have continuity between them.

The amount of power with this type of output is limited to 12V and 4 ohms - which is like 3-4 watts. You can bridge two of these together to make one "high-power" output, which is then floating ground, not common ground (if you connected the (-) to ground you would short one of the two bridged channels). That's where the early "high-power" radios came from - internally bridged 12V-internal amps.

(Today there are a lot of high-power HUs that use real tiny switching power supplies from what they say - that sort of thing has gotten really small - and that's why the power ratings of some HUs have gotten so much higher than they used to be. Doesn't mean that they are very good, but they aren't working with 12V all the way through, that's for sure.

This was a classic problem when adding "high-power" head units with floating ground outputs to older cars which used common-ground wiring and had the - wire just grounded - you had to re-wire all the speakers, pain in the neck.


At the risk of more bullshit, while this discussion of speaker floating and common ground is technically accurate, it isn't directly related to the question "why can't I bridge this amp?". The OE amp doesn't use common grounded outputs either, but neither do many aftermarket amps which are bridgable. We can't determine anything from that, if I understood your question correctly (perhaps you meant "Why can't any amp be bridged?)

Bridging an amp requires it to be designed to be able to be bridged. Yes, that means that it can't use already-internally-bridged IC outputs. There's also signal inversion at the input, there's lower impedance capability in two-channel mode that you have to have before you can bridge - which means more capable speaker output devices and a more capable power supply than your amp would need for a 4 ohm stereo system like the OE system.

No OE amp is going to leave money inside. Even if an OE did NOT use an internally-bridged IC for the output device (and I believe that there are some OE amps which don't), no OE manufacturer is going to build extra op-amp circuitry into the input for signal inversion (hell, they wouldn't use two more op-amps to cross over the tweeters!), or use a beefy enough power supply or beefy enough output transistors to support being bridged, because it costs more money and it won't create more sales, so it's wasted money to an OEM.

Bass Mechanic

thanks for typing that up elduderino.
and i will add that what eldude said about common and floating grond in an IC amp such as the OE amp. many times the output of the amplifier is coupled with a capacitor. sice a capicator blocks DC and passes AC. you can have a floating ground in an IC amp but again it is internal and is only there to allow the transistors to be biased at 6 volts (1/2 of 12)
but im getting pretty technical if i explain further and for this topic lets just leave it at the fact you cant and shouldnt bridge any 2 channels of any amp unless the manufacturer says it's ok to do so.

Bass Mechanic

yes like eldude said common grounded amps share the output with the chassis ground. you can ground the speakers to the chassis for that connection with no ill effects.


however now days most amps of this type are biased with a capacitor and are an AB (push pull ) type. its basically a smaller version of a regular amplifier without the power supply.
in a regular amplifier the power supply has a transformer (usually called a tetroid) it looks like a doughnut with wire wrapped around it.
this device has a side effect in that it generates power for the amplifier and is electrically isolated from the chassis ground.
this is what gives you a floating ground and depending on the amplifier between 60-100 volts internally to the outputs to drive the speakers with.
the transformer is driven by a switching system that generates a square wave AC signal into the transformer making it operate. (transformers need AC to work) it is used to step the voltage up at the expence of current to get the necessary power to create the watts you send to the speakers.

Tsx536

xaznperswaesonx

aww i love it when we all just get along! It's time for a :ultraghey:

Tsx536

^^