View Full Version : 2 amps on stock atl?
p123456789
10-10-2010, 10:55 PM
I have some kenwood components with a small 2 channel amp (20 amp fuse).
I would like to add a sub because the components just aren't cutting it in the low end department, I was wondering if 2 amps would kill the stock alternator my component amp is 150 watts rms and I'd like to add a 400 watt rms subwoofer amp and run a obcon godzilla box that my neighbor gave to me. my car has no power options so hopefully another amp wont kill it.
Palmer812
10-10-2010, 11:03 PM
You will be fine. That is not alot of power.
fnkngrv
10-10-2010, 11:34 PM
other information that you will need to verify is what your voltage is that is being provided from your HU to those amps. With more efficient signals comes cleaner power; cleaner power means less work for your amps and I would think less work by your alternator. I am sure that someone will chime in and correct me however I can tell you from my experience and watching voltmeters, etc I have noticed a difference. Either way, I am running my Bazooka at full gain (200 RMS) and my Alpine PDX four channel amp at 3/4 gain which is pushing I believe about 80 RMS to each of my drivers plus all of the other custom electrical draw without issue so I would wager you will be fine.
sqcomp
10-11-2010, 02:29 AM
The gain adjustment on the amplifier raise the sensitivity of the amplifier to the incoming signal Voltage. If one has the amp's gains cranked like that, I'd be more than willing to wager that on the top end of your volume that it can get pretty noisy.
"In my opinion (and MANY will disagree), the gains should be set so that the amplifier reaches full power just as the head unit reaches maximum output. This would allow you to use the entire range of the volume control (assuming that the head unit doesn't clip at full volume) and still get full power out of the amplifier. If you're an audiophile who likes listening to a flat response AND you have a speaker system that produces a flat response AND are listening to music that's properly recorded AND you've purchased the right amplifier, setting the gains like this will prevent clipping (again, assuming that the head unit doesn't clip at full volume). If you're into quality over quantity, this is (IMO) the best setup." -BCAE1.com
Aside from that side issue, the amplifiers load on your alternator is minimal DEPENDING on how hard you're railing on the volume. Our OEM alternators aren't particularly beefy. They are decent quality though. If loading your alternator down makes you nervous, consider my situation. I'm running three Audison LRx amplifiers off my alternator. I still have a good 14.3 Volts on startup and hover at 13.8 to 14 Volts driving to and from work. There are times when I have dipped the running Voltage down to 12.9. That was at idle and pulling a 2 Ohm mono load on my LRx 2.9 sub amplifier...something I normally don't do. In that situation I was testing out a pre loaded digital designs enclosure.
http://i720.photobucket.com/albums/ww203/sqcomp/2007%20Toyota%20Yaris%20S/CIMG1971.jpg
Here's something to read:
"If you have an alternator that can produce 120 amps of current (max) and the the total current demand from the electrical accessories (including the battery) is only 20 amps, the alternator will only produce the necessary current (20 amps) to maintain the target voltage (which is determined by the alternator's internal voltage regulator). Remember that the alternator monitors the electrical system's voltage. If the voltage starts to fall below the target voltage (approximately 13.8 volts depending on the alternator's design), the alternator produces more current to keep the voltage up. When the demand for current is low, the full current capacity of the alternator is not used/produced (a 120 amp alternator does not continuously produce 120 amps unless there is a sufficient current draw)." - BCAE1.com
The short answer to your question is...you'll be fine for the most part I'm sure.
p123456789
10-11-2010, 08:48 AM
thanks for the help sq comp I think if your car can handle those three huge amps my car should have no problem with my two smaller amps. so what your saying is that I need to set my amp up so I can still use the full volume level? and how do I know which amp to buy according to which head unit I have a pioneer premier and I'm running a mtx rpt 202 I only paid 20 bucks for the amp on ebay and it was local so I couldnt pass it up. I listen to every kind of music out there mostly rock though, can you recommend a good amp for a single 12 inch sub? I think i'm getting a obcon gozilla box because I can get it dirt cheap although it does have some damage on one of the corners that I think I can fix.
TheDriver916
10-11-2010, 01:58 PM
i have a kicker zx350.4 for my mids and highs and a alpine mrp 500 both beating at the same time and only on long low bass notes will my lights dim. I was pretty impressed that it handles it no problem.
sqcomp
10-11-2010, 01:59 PM
Notice that the gain management ditty I have up there notes about quality listening. A lot of people, I'd estimate at least 90%, don't give a hoot about non-clipped signals.
I'm not suggesting that you need to trade in what you have. Rather just to be aware about the different Voltage outputs on source units. If you have a "weaker output", let's say 2 Volts, your amp gains are going to need to be cracked open more to be more sensitive to the lower Voltage that the source supplies.
I'd imagine that since you're on a budget you don't want to spend the money, probably an hours worth of labor, to have a reputable shop level match your source and amps. There area couple of solutions but the involve spending a little more money to buy test speakers and what not. By ear is probably the way you'll go. Just know when you set your gains by ear, by the time you hear distortion, clipping has already been happening for a bit.
As for reccomendations? I'd want to know the power handling of the sub...actually...makes me wonder what you're looking for overall. I have heard a loaded enclosure with an 8" sub that destroys...I mean absolutely DESTROYS most vented 12"s on the market. Let's talk more about what you want.
TD916 - What have you done for upgrades on your charging system? I'm running with 165 Amps of potential draw and at my loudest I don't dim...although, now that I think about it, I'm running HIDs so they wouldn't anyway. They'd just shut off. Regardless, you're obviously having some Voltage draw issues. Have you even stuck a Voltimeter on your system to see what is happening?
TheDriver916
10-11-2010, 06:30 PM
i havent put a volt meter on it yet but im guessing im hovering around 12.5, and i dont push my system hard for long periods of time. Im a wuss and im always worrying about burning up the voice coils lol
Palmer812
10-11-2010, 08:40 PM
SQ, you are right but most head units on the market nowadays do clip. Your's is an exception. The $1000 Alpine I have has a sorry 2 volt and starts to clip at 24-25 out of 35. I have had an Alpine 7909AE and a Nakamichi CD700 that wouldn't clip at all. My sub amp is close to full gain but my 4 channel is just over half. I have it bridged to 300x2 on my fronts.
p123456789
10-11-2010, 09:14 PM
I have 4v pre outs on my pioneer premier hu should I run my amp at 3/4 so? also my neighbor gave me an obcon godzilla single 12'' ported box what sub is a good match for this box I listen to mostly hard rock. what does clipping sound like, does it sorta sound like distortion?
Palmer812
10-11-2010, 09:42 PM
Yes clipping is distortion. The easiest way to set the gain on an amplifier with no special tools required is to start with the amplifier all the way down. Then set your headunit to 3/4 volume and then slowly bring up the gain on the amplifier until is starts to clip. As far as what sub you need for that box we need to know more. What size is the box and what size is the port?
sqcomp
10-11-2010, 10:19 PM
To add more to what Palmer is saying, when you HEAR the clipping, it's bad. Mmmmm'kay? :D
A lot of lower end source units clip at full volume (regrettably). So 3/4 volume isn't a bad idea per se...it just limits the total range of the Voltage. It keeps you safe though. The amps gains having to be at 3/4? Well, there's just something wrong there then. That means that the Voltage from the source isn't what it advertises. 4 true Volts should be plenty. Actually that's what I run my source at "max", a little over 4 Volts. I scoped mine though and set it accordingly.
Palmer...7909 love over here! That was my first tuner. The 25th anniversary '09. It is a wonderful deck. I had fun with the Naks as well working for my first audio shop. Try to scope your amps with those gain settings at the speaker outs on the amps. Something tells me you'll be suprised how much clipping you see.
Driver...if you're hovering around 12.5 Volts, that's something serious. That means your battery is holding your system up. Take a startup read off the alternator if at all possible. Hell, I wouldn't worry about the voice coils! I'd think long and hard about the charging system. You can still drive without subs, you can't do squat without an alternator. Believe me, it happened to me once many years ago. It won't happen again.
Palmer812
10-11-2010, 10:49 PM
My 7909 was a 30th. anniversary that I got dirt cheap. I regret ever selling it. When I sold it I put in a then top of the line Alpine deck that was supposed to be 4 volt. That was bs. I had to regain both of my amps and I still couldn't get it as loud as it was with the '09.
sqcomp
10-12-2010, 02:26 AM
Oh yeah, the '09 is a real 4 Volt. The nice thing about that tuner is that it is a great CD transport. That CDS button is great for tuning and RTA work. Signal Voltage is life! I'm working with 4.9 unclipped Volts with my tune now.
p123456789
10-12-2010, 01:52 PM
I think my rca's are just junk I used scosche rca's from walmart so I think I might upgrade those. the music sound really dirty when I turn it up loud like you can't tell one not from the other they all kinda flow together. or it could be my kenwood components I might go get some alpine 3 ways and ditch the component setup. does a good set of rca's make a difference can you use household rca's?. I also swapped amps and it sounds exactly the same I swapped to a jbl 4 channel.
derickveliz2
10-12-2010, 02:39 PM
Yes clipping is distortion. The easiest way to set the gain on an amplifier with no special tools required is to start with the amplifier all the way down. Then set your headunit to 3/4 volume and then slowly bring up the gain on the amplifier until is starts to clip. As far as what sub you need for that box we need to know more. What size is the box and what size is the port?
Could you guys describe me "Clipping"?
Thanks
Alien Mantis
10-12-2010, 05:40 PM
Could you guys describe me "Clipping"?
http://en.wikipedia.org/wiki/Clipping_%28audio%29
I believe you were going to tell us what subwoofer setup you decided to try?
*AHEM*
:biggrin:
derickveliz2
10-12-2010, 05:50 PM
http://en.wikipedia.org/wiki/Clipping_%28audio%29
I believe you were going to tell us what subwoofer setup you decided to try?
*AHEM*
:biggrin:
Thanks, I didn't forget !
I'm still getting quotes from different dealers, looks like it would be a 12" (?)
.:thumbsup:
Palmer812
10-12-2010, 07:00 PM
You're only 800 miles from me. Let me know before you buy. I might just sell you the stuff and ship it to you. I can match any price you find online.
p123456789
10-12-2010, 10:14 PM
well I figured out my problem its my head unit, I hooked up my ipod straight into the amp and it sounds AMAZING lol I can turn it up so loud without any distortion. The head unit is only 6 months old (came out of friends truck) and its a fairly high end pioneer premieer with all the adjustments you would ever need. even while playing cd's i can hear tons of feedback when I switch songs or at low volume. even at low volume I can hear alot of distortion even on local stations. any recomendations for a head unit around 200 or so? I want someting simple and easy to adjust.
Palmer812
10-12-2010, 11:29 PM
What about getting the Pioneer repaired? The Premier stuff has a 2 year warranty and you said it was only 6 months old. If you do go new for around $200 I love the Kenwood Excelon KDC-X794 especially if you use your Ipod alot. I have one in my wife's xb.
p123456789
10-13-2010, 12:00 AM
not sure if I can my friend bought it and i'd rather not hasle him.
sqcomp
10-13-2010, 01:19 AM
Get some subbage going on!
yaris2010RS
10-13-2010, 09:42 AM
this is a very informative thread. my issue is using my stock HU and my system set up, if volume is too loud the speakers crack and bounce around....is that my hu messing up or is that the speakers being over powered?
sqcomp
10-13-2010, 11:14 AM
Ummm...if your speakers are bouncing around, I'd say that is problem #1 at the moment. Too much power is only really a problem if you can't control the variable potentiometer output off the digital signal platform from the media transport. Like that one? :)
The only other issue with overpowering is crossover issues on speakers. That's a whole thread in and of itself.
Something tells me though, that it's not "overpowering" that's the case here...especially from a stock source.
TheDriver916
10-14-2010, 02:47 PM
i have a high low converter because i was trying to stay away from an aftermarket deck for the simple fact that people wont break in and try and steal it. but going from an 8 band eq that i can tune every song in perfectly for my mids and highs to.... treble.... just doesnt cut it. is there anything i can do to clean up the sound?
sqcomp
10-14-2010, 06:05 PM
When you say clean up the sound, what do you mean? What is the sound in your car doing (or not doing)?
You can buy an outboard eq. JBL, Alpine, Audison, Pioneer, Audio Control...they all make equipment that can assist your tuning.
I can speak for myself and possibly derick, we have 1/3rd octave control plus some nice time alignment. Your options are open still.
Incillio1
10-15-2010, 04:52 AM
The gain adjustment on the amplifier raise the sensitivity of the amplifier to the incoming signal Voltage. If one has the amp's gains cranked like that, I'd be more than willing to wager that on the top end of your volume that it can get pretty noisy.
"In my opinion (and MANY will disagree), the gains should be set so that the amplifier reaches full power just as the head unit reaches maximum output. This would allow you to use the entire range of the volume control (assuming that the head unit doesn't clip at full volume) and still get full power out of the amplifier. If you're an audiophile who likes listening to a flat response AND you have a speaker system that produces a flat response AND are listening to music that's properly recorded AND you've purchased the right amplifier, setting the gains like this will prevent clipping (again, assuming that the head unit doesn't clip at full volume). If you're into quality over quantity, this is (IMO) the best setup." -BCAE1.com
Aside from that side issue, the amplifiers load on your alternator is minimal DEPENDING on how hard you're railing on the volume. Our OEM alternators aren't particularly beefy. They are decent quality though. If loading your alternator down makes you nervous, consider my situation. I'm running three Audison LRx amplifiers off my alternator. I still have a good 14.3 Volts on startup and hover at 13.8 to 14 Volts driving to and from work. There are times when I have dipped the running Voltage down to 12.9. That was at idle and pulling a 2 Ohm mono load on my LRx 2.9 sub amplifier...something I normally don't do. In that situation I was testing out a pre loaded digital designs enclosure.
http://i720.photobucket.com/albums/ww203/sqcomp/2007%20Toyota%20Yaris%20S/CIMG1971.jpg
Here's something to read:
"If you have an alternator that can produce 120 amps of current (max) and the the total current demand from the electrical accessories (including the battery) is only 20 amps, the alternator will only produce the necessary current (20 amps) to maintain the target voltage (which is determined by the alternator's internal voltage regulator). Remember that the alternator monitors the electrical system's voltage. If the voltage starts to fall below the target voltage (approximately 13.8 volts depending on the alternator's design), the alternator produces more current to keep the voltage up. When the demand for current is low, the full current capacity of the alternator is not used/produced (a 120 amp alternator does not continuously produce 120 amps unless there is a sufficient current draw)." - BCAE1.com
The short answer to your question is...you'll be fine for the most part I'm sure.
How does that sound and what size sub is that? Are there two subs in there. One on each side. Im thinking of doing something like that
Palmer812
10-15-2010, 03:15 PM
That is a 15". There is only one.
typicaljawaiian808
10-15-2010, 08:09 PM
went through the entire build log last night...nice work
sqcomp
10-16-2010, 05:40 PM
Not done yet. As I write this I'm sitting with a 3x MECA master champ and we're going over changes and little tweaks for the yaris. There WILL be more to come.
How does it sound? Well, after I put in the back seats I have to move around the sub to get the SPL back. Damned sedans. It is in a temporary enclosure right now. It sounds proper actually. Plenty of low end authority with very fast response.
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