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captcrash
05-26-2014, 08:18 PM
I am looking for opinions on what amp or amps you think that would be best for me. I do not know much about car audio but am trying to learn as I go. I am much better with engines. The car is a 69 Camaro street car. It will be a weekend cruiser. Here are the parts that I have already:
Kenwood KDC-X396 deck which has (22 watts RMS/50 peak x 4 channels)
Alpine Tweeters 100w rms 300w peak
Kenwood 4in in dash 20w rms 120w peak
2 JL Audio 10inch subs 300w RMS 600w peak

I may use another pair of 4" or 6x9s depending on room by the back seat.

I am looking to buy an amp but I don't know if I would be better off with a 5 channel amp and power the sups the tweets and the other set of speakers in the back seat with it, or should I get a mono amp for the subs and a 4 channel for the others. I would like enough power to where there is no overheating issue. I was looking at the Kenwood Excelon XR900-5 or the JL Audio XD1000/5v2 (http://www.crutchfield.com/p_13698258/JL-Audio-XD1000-5v2.html?tp=115) but I don't know if it is worth twice the money.
Thanks,
Brain

scott_fx
05-26-2014, 10:07 PM
I guess the primary question is how load is your car going to be? Second, do you plan in sound deadening your car? If you're going to have a loud car then you can go with a less expensive brand. Reason being, car audio have a very sharp point of diminishing returns. The louder your car is the less you'll notice the difference between a $300 amp v a $1000 amp.

As a rule of thumb I always try to power my speakers with at least 100 wpc. This isn't for spl aka loudness but rather it allows you amp to be turned down allowing it to play at volume with less noise.

Jl makes amazing stuff. You won't be disappointed but you may not hear the difference driving down the highway with long tube headers and a loud exhaust.

As for separate v combo amps. I prefer separates because if one blows, you have a more economical fix.

Any way you could install larger speakers in the kicks? Thee are many advantages to having 6.5"+up front

captcrash
05-27-2014, 07:13 PM
Thanks for the reply. The car will be loud. It is 643 horse and it will have 3" exhaust. The exhaust will be ran out the back, and I will run longer mufflers. Also the entire underside of the car, as well as most of the interior was sprayed with Lizzard skin for noise and heat. Also I will be using extra dynamat under the carpet and in the doors, to try and make the inside as comfortable as I can. I would like to keep the vents in the kick panels for airflow as there will be no ac. I have thought about putting speakers in front of the console pointing down towards your feet but I didn't know if that would help. Also I don't know if I could get 6" speakers in there anyway.
Brian

scott_fx
05-27-2014, 08:19 PM
Thanks for the reply. The car will be loud. It is 643 horse and it will have 3" exhaust. The exhaust will be ran out the back, and I will run longer mufflers. Also the entire underside of the car, as well as most of the interior was sprayed with Lizzard skin for noise and heat. Also I will be using extra dynamat under the carpet and in the doors, to try and make the inside as comfortable as I can. I would like to keep the vents in the kick panels for airflow as there will be no ac. I have thought about putting speakers in front of the console pointing down towards your feet but I didn't know if that would help. Also I don't know if I could get 6" speakers in there anyway.
Brian
Great! sound deadening is important! but...dynamat will only do so much for you. it will help with deadening noise created by the panels vibrating. but it wont do much to absorb noise. for that you'll need a layer of foam over the deadener. i'm using ensolite on top of my deadener (bxt II) http://www.raamaudio.com/categories/Mat-and-Foam-Products/ another suggestion is to get some acoustical foam squares from parts express and stuff them up in the crevices behind the dash. also, if you can, it wouldn't hurt to do the roof.

give this a read:
http://www.raamaudio.com/pages/How%252dTo.html


I usually try to run pretty high end gear in my car because i'm:1) an addict 2) like the higher build quality components 3) very into the hobby of car audio. That being said I honestly think if you want to save some money, you'll be fine with kenwood. Another brand to look into is the new soundstream reference line. Back in the day these amps were hard to beat for sound quality. they have since been bought out by an asain company and the quality tanked and then (i believe they got bought out again) and now the reference line is a very solid amp for not that much money. I would strongly consider looking into them.
here is what i'd get over the kenwood
http://www.woofersetc.com/p-7744-ref4760-soundstream-4-ch-760-watt-rms-class-ab-reference-series-power-amplifier.aspx
http://www.woofersetc.com/p-7746-ref1500-soundstream-monoblock-500-watt-rms-reference-series-power-amplifier.aspx

all in all thought, the amount of power you have available will often times outshine the small improvements of higher end gear.


the Achilles heal of this system is going to be those 4" mids though. they are just going to strain if you go much lower then 140hz i bet. That's going to force you to play a wider frequency through your sub. The disadvantage of this is it's going to bring the music behind you and ruin your imaging and soundstage.

I'm wondering if actually getting a 6.5" mid firing down from under the dash would actually be a better compromise... let me do some research for you and ask around

scott_fx
05-27-2014, 11:45 PM
So I think it could work but not with your current equipment. You'd need a 3" full range driver instead if the tweets then you'd need a 6.5" midbass or larger if you could fit it. You'd then need to do some eq'ing, x-over, and time alignment. But your headunit doesn't support that. You'd need a pioneer Deh 80prs.

If you did go that route you could opt for these full range drivers:
http://www.parts-express.com/peerless-830986-3-full-range-woofer--264-1056

And maybe a peerless or Dayton audio midbass. Both have great sq/price ratio
http://www.parts-express.com/dayton-audio-rs180p-4-7-reference-paper-woofer-4-ohm--295-375

chuckd71
05-28-2014, 03:59 AM
Get a 5 channel amp and a couple sets of 6.5 inch components. In that car you'll never be able to tell the difference between that and a $1,500 system anyway.
69 camaro w/ no AC = loud car with windows constantly down. No reason to go overboard with the stereo.

GrabberGT
05-28-2014, 06:19 AM
Im in the same boat (load car). I have 5.25 components in all 4 corners and want more volume. At the volume I have to turn it up to in order to hear it over road, wind, and engine noise, it becomes quite distorted. I even have my crossover set to send most of the lowers to the sub. I've thought of doubling up on speakers rather than going larger as a way to 1)have more flexibility in mounting and 2)if they are bridged together and can be run at 2ohm thus drawing more power from the amp. What are your thoughts? Im looking at a 5-channel amp under the rear seat to save space.

scott_fx
05-28-2014, 07:53 AM
Im in the same boat (load car). I have 5.25 components in all 4 corners and want more volume. At the volume I have to turn it up to in order to hear it over road, wind, and engine noise, it becomes quite distorted. I even have my crossover set to send most of the lowers to the sub. I've thought of doubling up on speakers rather than going larger as a way to 1)have more flexibility in mounting and 2)if they are bridged together and can be run at 2ohm thus drawing more power from the amp. What are your thoughts? Im looking at a 5-channel amp under the rear seat to save space.

Your 5.25" mids are holding you back a bit. if you can fit something larger like a 6.5" or 7" mid you'll be in a better position. also, if they are mounted in the doors then it'll help a lot to at least sound deaden the doors and also try to patch any holes that will let air in/out. this can be as easy as using some silicone and flashing material then covering that with dampening material. What is your x-over set at? ~120hz? Also, did you set your gains correctly on your amp? Your first plan of attack should be to stick with your equipment and try to get the most of them through proper installation (read that deadener link i posted) and see if that's the issue. if not then move onto component swapping.

Probably the worst thing you can do is double up on the speakers and here is why. First rule of car audio is k.i.s.s. I never run rear speakers, only fronts. the reason being is that you don't want to have the same signal playing from two different point sources. When this happens you have the same soundwave reaching your ear at different times. depenind on frequency and reflections the soundwaves can either add or subtract each other. What you end up with is muddy sound that is hard to eq. A larger mid is the way to go for sure. For an example I have a 7" mid and a larger format tweeter (planned for my chevelle once i get it back, but had the same set up in my last car). The large format tweeter can play a bit lower then smaller tweeters giving me more flexibility in my setup and tune. This allows me to tweak my speakers (aka drivers) to play at their sweet spot and often times avoid some of the break up you get when some mids try to play toward the higher frequencies.

With running 2 ohms your amp is going to work harder. that will ultimately mean more noise in your system. I would say get the power you need at 4 ohms and take that factor out of the equation. (The mid I'm running right now is actually an 8 ohm driver: http://www.madisoundspeakerstore.com/seas-woofers-6-7/seas-excel-w18nx-001-e0042-nextel-cone-7-woofer/) But more goes into how loud a speaker will get then just the impedance (measured in ohms). Sensitivity and how that is measured also has a lot to do with it. My 8 ohm driver will play just as loud as a comparable 4 ohm driver powered by the same amp. here is another helpful write up about 4 ohm v 8 ohm drivers (http://www.diymobileaudio.com/forum/how-articles-provided-our-members/31-real-deal-8-ohm-drivers.html)


if you want to save space, take a look at the nano amps that they have out there (these things are tiny!):
http://www.sonicelectronix.com/search?keyword=nano&query_id=30411258&query_code=261228&SearchClickout[query_id]=30411258&product_type=7
http://www.diymobileaudio.com/forum/member-reviews-product-comparisons/93284-massive-audio-nano-nx5-nx4-nx2-review.html

DippedInSauce
05-29-2014, 10:10 AM
I'd go with JL weather you choose a mono sub amp and a four channel or a single five channel. They make the best stuff. I have a pair of their slash series amps in one of my cars and they've performed flawlessly for almost ten years.

hifi875
05-29-2014, 05:58 PM
Go with either a Jl xd700/5 or the hd900/5. I run the hd900/5 in my 69 w c5 components up front in the kicks and jl c3 6x9s. Sounds fine. My car is full dynamatted firewall to tail panel doors quarters and all. Also use dynapad on top of dynamat and under carpet. Alternative would be the kenwood excelon xr900/5. It's a nice piece very clean and good sub power. I own a custom a/v shop and a full line dealer for alpine Jl and kenwood excelon. If you have any questions just pm me

captcrash
06-06-2014, 10:54 AM
Thanks everyone for the help. Another question that I have is on interference with a class D amp. I plan to run the amp in the trunk, and there will be 2 batteries back there as well. The radio antenna and the MSD box and the other electronics will be under the dash. Also I have RCA outputs from the deck to signal the amp. Since a battery is only for storage, I don't think that I would have any issues with them being close to the amp. Everything else should be far enough away that there shouldn't be any interference, right?
Thanks,
Brian

scott_fx
06-06-2014, 10:58 AM
Thanks everyone for the help. Another question that I have is on interference with a class D amp. I plan to run the amp in the trunk, and there will be 2 batteries back there as well. The radio antenna and the MSD box and the other electronics will be under the dash. Also I have RCA outputs from the deck to signal the amp. Since a battery is only for storage, I don't think that I would have any issues with them being close to the amp. Everything else should be far enough away that there shouldn't be any interference, right?
Thanks,
Brian

amps chassis are metal and they are grounded, you dont really get an emf noise. you'll be fine.