Finally getting around to the sound system

Hey guy's (and quite possibly gals), I am semi new to this section and just looking for some imput. I finally finished up messing around with my engine and now have turned my interest into my audio system wish was extremely lame with the exception of my Pioneer GM designed din and half head unit (deh-45dh) which I love. However the gm-x972 800 amp I bought a while ago and was planning at some point to just throw a half assed box up on the back ledge of my 94 Pontiac Formula/Firebird but the once I started doing a little research. I decided to pick up all new 4 way Pioneer speakers (TS-A1681S 6 1/2 in front and TS-A1780R 6 3/4 in the back) and I am also putting in a Q-logic custom fit box in the back which is going to hold my 2 12 inch Pioneer subs. So after I bought my subs and just to make sure I wasn't going to run into any snags I double checked the stats of my subs, but after putting in my model number into Pioneers website. I came across this http://www.pioneerelectronics.com/pna/press/release/detail/0,,2076_4313_41275,00.html , So now they gave me the options of another Pioneer amp but they no longer make anything really all that similiar to the stats on my current amp, the only one close is a 600 watt 4 channel (gm-6100F) that if bridged for 2 channel deliver 150 RMS watts to each sub and max 300. Which is the same as the other one but my question with that one is that it gives the options of stereo or mono with the 2 channel , if I go Stereo which would change the ground terminals, does that affect the watts? and is there any other negative effects of bridging, that will effect sound quality?. Like I said I am semi new to this, so any feedbacks on things I should be aware would be appreciated as well as any Pioneer amp you would recommend I take in place of mine. Thanks

Edit- Sorry thats so long :rolleyes:, I ramble :uhoh:

Running your amp stereo will not have anything to do with your grounds. well there is a lot of wrong info there, check this out www.bcae1.com , good place to learn the basics of mobile audio

I am talking about the terminals on the amp to the subs, Not the main ground for the vehicle. They have a mono and stereo routing for the sub on the amp. My question is if it will have any effect on watts. Thanks for the reply

Your amp is 2 channel, so bridging your left output an right output together will create the mono load, and using the channels seperately is stereo. If just to say each channel is 100w, bridged power would be 200w x1. Just make sure you dont go below the ohm load for the amp in Mono.

No, the model amp I am looking to get as a replacement for mine which is a recall is a 4 channel amp. When run as a 2 channel it gives you the option of Stereo or Mono , which use seperate terminals on the amp to ground the speakers/negative side polarity. My question is, do I lose any power from using the stereo versus mono option for the two channel and The power isn't doubled by going to 2 channel to a mono or from a 4 channel to a 2 channel its more than doubled. For instance my current amp that has been recalled is a 800 watt peak amp with 400 watts RMS when used as a single channel/mono amp but when you use it as a two channel it only powers each channel to 300 watt peak power and 150 RMS. Which is less than half per channel.

i understand what your saying. you shouldnt run your subs stereo, you probably want to run them in mono. but either way, there shouldnt be any power loss.

Thanks, that was what I was looking for.

well if you bench tested your amp the actual watts will be double or somewhere close than each channel when bridged.

i thought it would be closer to between triple and double the amount??

Thanks, I will keep that in mind. I am now trying to decide if I should now use a seperate smaller amp for the front 4 speakers as they can handle alot more power than my head unit is making but if I use two external amps, how does the amp remote signal work from the head unit, do I just splice the wire and run it to both amps if I go that route? Or is there another way people do that. My speakers can handle 50 watts RMS (260 watts peak) and my head unit is only making 17 watts RMS (35 watts Peak).

yea im actually about to do the same thing and add a second amp for my four speakers. but for the remote turn on wire theres two options, you can just splice the wire(which i have now for my crossover and my amp which works fine), or you can do it the safe way and use a relay, but that takes more effort.
or actually you might want to use an inline fuse in the remote wire, and just splice it afterwards, youll probe need a .5 amp fuse.

btw, if you have the money, id use a second amp to power the 4 speakers.
1. it will make the music louder
2. it gives you better sq
3. youll be able to filter out the low frequencies, giving a better overall sound stage and youll protect your speakers from blowing easier.
if you do this though i highly recomend getting an active crossover, which should run you maybe 50 dollars for a decent one.

Bridging amps doesnt make more power.

Example

100x2@4ohm
200x2@2ohm
400x2@1ohm

200x1@8ohm
400x1@4ohm
800x1@2ohm

the total power output is the same

i didnt read your whole first post...sorry, i feel like shit and just got finished with a latin exam...too much reading bunched togather for me.

Well , all I know is from the pioneer ratings. They rate my current amp that I am sending back at 150 RMSx2 @ 4 ohms but bridged for 1 channel they rate it at 400 RMS x1 @ 4ohm with double the rms as peak for each or are you saying because of the half the ohms being used is why the wattage is different?

right, im confused now too
if you bridge your example amp, you are given twice as many watts(800) as compared to the two channels putting out 200w@2ohms each.
please explain.

look back at my example ratings... 150w doubles would be 300w, however that would be at 8ohm, not 4 ohm. cutting the resistance in half allows for more current so 400w is feasable.

ok, i kinda understand
but say with your example sub ratings, you ran 2 DVC subs on 2 channels, 4ohms each, you would get 200w total(100x2)
now if you ran the same amp bridged with one channel and the same 2 DVC subs in a series/parralel configuration, so theres still a 4ohm load on the amp, you would get 400w total right?

did you mean if you just ran the subs in series to have an 8ohm impedence so you still had 200w total?
i didnt really understand your last post, sorry

100x2@4ohm
200x2@2ohm
400x2@1ohm

200x1@8ohm
400x1@4ohm
800x1@2ohm

if you have a single D4 driver you could wire each coil at 4ohm to get 200w total.
the amp drives it as two individual 4ohm loads.
if you wire the coils in parallel to yeild a 2ohm load and bridge the amp you will get 800w, this is because you are cutting the load in half and combining the power of each chanel into one.

the last post was explaining ow an amp could have 300w total in stereo and 400w in mono with the same load.
the amp should have ratings like this

150x2@4ohm
200x2@2ohm

300x1@8ohm
400x1@4ohm

the power does not double when the load is cut in half because the power supply of the amp cannot supply the needed current :) however the circutry is stable at 2ohm stereo they just dont list it, under certian circumstances amps are more stable bridged than stereo but rarely...but if it where its minimum loads could be the same for mono and stereo.

ahhhh that makes so much sense. lol i dunno why i didnt get that before.
so how can i tell if my amp is 2ohm stable though, because i cant find the stats online at all(mtx thunder 420 i think)

The link that MannyB gave is EXTREMELY helpful. i've been reading it and its helped a lot.

here's a link to one of the chapters that would re-enforce what Fryman's trying to say: http://www.bcae1.com/bridging.htm

ahhhh that makes so much sense. lol i dunno why i didnt get that before.
so how can i tell if my amp is 2ohm stable though, because i cant find the stats online at all(mtx thunder 420 i think)

yeah, your amp is 2-ohm stable, but in stereo only! if you use a 2ohm load in mono, you'll fry ur amp. again, read the link i gave in prev post, it explains in full detail.

(thnx mannyb for recomending that link a while back, its killer)

yea that link helped alot, thanks.

so if im looking to buy two subs for that same 2channel mtx amp(2alpine type-r's), would it be better to run the two 4ohm+4ohm DVC drivers in stereo in parrallel with a 2ohm stereo load, or run them bridged with a series/parrallel connection for a 4ohm mono load? or are they exactly the same? would the amp be more stable with a 2ohm stereo load?

yea that link helped alot, thanks.

so if im looking to buy two subs for that same 2channel mtx amp(2alpine type-r's), would it be better to run the two 4ohm+4ohm DVC drivers in stereo in parrallel with a 2ohm stereo load, or run them bridged with a series/parrallel connection for a 4ohm mono load? or are they exactly the same? would the amp be more stable with a 2ohm stereo load?


well if ur saying u've got the 420w mtx 421d, its a mono amp, not a 2-channel. ur subs can handle 500w rms. ur amp gives 210w rms to a 4 ohm load, and 420 to a 2 ohm load. this is where i stop being of any use, cuz i get confused when it comes mono amps. I'm guessing you want to wire the subs so that the amp sees a 2 ohm load. now, 2 ohm stereo loads are safe, thats what amps are stable at when they say 2 ohm stable. but does a mono amp even have stereo wiring? no, right? so that's when i get confused. a mono amp that says 2 ohm stable, is it stable at 2 ohm mono? EDIT: (i.e. wiring 2 4ohm subs in parallel?)

no i have the the mtx thunder420 amp, i dont know how many watts it puts out or anything, i havent been able to find any info on it at all. but yea an amp thats 2 ohm stereo stable is not 2ohm mono stable. the two subs i had before were 300w rms each and they powered them pretty well, so its somewhere around there for each channel i think.

but i still dontknow if i should wire them in stereo or mono bridged with a 4ohm amp load

no i have the the mtx thunder420 amp, i dont know how many watts it puts out or anything, i havent been able to find any info on it at all. but yea an amp thats 2 ohm stereo stable is not 2ohm mono stable. the two subs i had before were 300w rms each and they powered them pretty well, so its somewhere around there for each channel i think.

but i still dontknow if i should wire them in stereo or mono bridged with a 4ohm amp load

bridged power would be the one that gives u more watts...
i don't think mtx had a 420 model, only the 421 D-class mono, rated at 420watts

hm, i could of sworn it says mtx thunder 420 on it, ill check next time, its really bothering me that i dont know what amp i have lol.