System Critique Requested

In the coming months, I'm planning on putting together my second system (my first was about 6 years ago, and is long gone). Below is what I was thinking of putting together, and I'd like for the experts to critique my idea...

Music: Rock, alternative, rap, electronic, and metal (in descending order of play).

EST. TOTAL: $1550 + materials (i.e., box materials, wires, etc.)

Headunit: $200
Kenwood Excellon KDC-794

Amps: $770

- Mids & Highs: $350
Zapco i450 [EDIT: The i-Force amps receive mixed online reviews (in forums, fwiw)...I initially thought that these were manufactured in the U.S., but it looks like Zapco has sourced this out to a Chinese manufacturer...hmmm. ]
> @ 4 ohms = 4 x 75w

- Sub: $420
Zapco i600 [EDIT: see above "EDIT".]
> @ 4 ohms = 300w

Speakers: $580

- Mids & Highs: $320
> Front: $220
Pioneer Premier TS-D720C

> Rear: $100 (my bargain speakers, that I doubt I’ll hear much)
Polk Audio db571

- Sub: $260
One (1) JL 12W3v3-4

Also: I was thinking of adding a power cap...ideas (yes/no; type; size)...my thoughts were 4 to 10 farad (though I think that anything over 4 would be unnecessary).

Last: I'm dead set on nothing...if you suggest an alternative or an addition, please advise me accordingly.

All suggestions/feedback appreciated.

 

IMO money is better spent on better front speakers than those amps. Kenwood makes an excellent all in one amp (Excelon XR-5S) that will give you the same power that will draw less power from your alternator and you dont need a capacitor IMO. Its 80x4 and 350x1 at 4 Ohms.

If you intend to go sealed the IDQ v3 will cost $20 less than your quoted price shipped from woofers etc.

I am not fond of either of your mid and high choices. A friend has the Pioneer Premiers in his Miata with a PDX5 and its not great sounding. I dont like any of the Polk speakers... not even the highest end SR speakers (very directional which is bad in our set up with off axis tweets in doors) and certainly not the db speakers.

You will also need to put aside a hundredish for wires for power, ground, remote turn on, speakers, a fuse block or inline fuse, etc. An all in one amp means just a single inline fuse and no distribution block too... another cost saver.

The JL C5 components are much better than the Pioneer Premiers IMO. Just lack a little precision in complicated music, though still better than Pioneers. The midbass is killer though. You can get those for about $280 if you shop around.

 

The XR-5S definitely has a smaller footprint, and is a much less expensive option. It also has nice (really nice) looks, and better speaker connections (imo).



But, Kenwood's THD+N is 1% @ 4ohms (ouch), whereas the I-Force comes in at <0.025% @ 4ohms. Nonethless, with my budget build and limited space, I'll seriously consider it.

As far as speakers go, I'll look into your JL recommendations. I'm not familiar with their mids/highs (but I dig their subs). FWIW, I chose the Pioneers based on caraudiomag.com's recommendation, and the relatively low price point.

Thank you for your input, DevL...I appreciate it!

[EDIT: regarding wires, etc., I actually priced the same at an additional $150-$175...it adds up quickly. o_o]

 

No offense but i with 1550 here is what i would buy. (I do own a shop and install this stuff daily FYI).

Alpine headunit (look into Alpine Imprint compatable units if you really want to maximize your sound quality)

JL HD900/5 amp
JL c2 6.5" components or the front and JL c2 6.5" coax for the rear
JL w3v3 woofer-4

just my 2cents

EDIT: don't waste a dime on a power cap, just do a grounding (big 3) mod

 

^ what's the story with D-class amps? I've always owned A/B, and with the exception of a hot PPI (which could've been the installer's fault), I've always had good luck with A/B.

 

Classes of Amplifiers
An amplifier is classified according to its circuit design and the way its output stages are powered. Although some may assume that for every portion of the input signal there is corresponding 100% output from the amplifier, power dissipation (in the form of heat) and distortion of the audio signal are two key factors in determining the efficiency and fidelity of an amplifier. Each class has its own performance characteristics and advantages.

• Class A amplifiers are desirable for the high quality of their sound, but, because of the configuration of its transistors, a pure class A amplifier is inefficient and runs very hot. This is because even when there is no audio signal, the output transistors always have current running through them. The current flowing through the output transistors (with no audio signal) causes the amp to heat up unnecessarily, and "waste" input energy. Most car amplifiers that boast "Class A" circuitry are really Class A/Class AB hybrids.
• The output transistors of Class B amplifiers actually turn off for half of every signal cycle. This improves efficiency and saves energy, but introduces distortion during the switching periods.
• By far the most common car amp design, Class AB amplifiers also allow current to run through the output transistors when there is no audio signal, but at a much lower level. A class AB amplifier runs cooler, and therefore, more efficiently than a class A, with low distortion and high reliability.
• Class D amplifiers use output transistors as switches to control power distribution — the transistors rapidly switch on and off at least twice during every signal cycle. Class D amps boast higher efficiency, produce less heat, and draw less current than traditional Class AB designs. Class D amplifiers produce higher distortion than AB designs due to the high-speed switching on and off of the transistors, but this distortion occurs at high frequencies that are typically removed by a low-pass filter.

 

Thank you, Jake.

 

I have a JL 900/5 but it retials for $1000. I paid $675 which is a steal. The Kenwood Class D amps sound fine... better than the old PDX and about equal to the new PDX. The JL HD amps are a tiny bit better but you be hard pressed to hear the difference if you dont have really high end speakers.

It used to be Class D amps did not have te switching speed to do mids and highs. Technology has moved to a point that its no longer an issue in the new sound quality mid/high Class D amps. The only thing I noticed vs my old Precision Power amps is less bulk, less heat, and no thermal shutdown.

 

Thanks, DevL! The cheapest (reliable) source I could find has the JL 900/5 for $799 -- which doesn't change my total cost that much.

Nonetheless, I'm still seriously considering that Kenwood...

 

The THD number is something I really wouldn't worry about. You don't seem to listen to anything or run equipment that you'll be able to hear the difference. Even in the house I doubt I could even hear the difference. It's almost an arbitrary figure until it gets higher.

And I'd imagine the THD number on that is the highest point with it which involves the sub channel which is typically higher in most cases than other full range channels if I remember correctly.

Those speakers are fine that you picked but I agree you don't need to spend the money on the Zapco stuff. It's just not going to yield any apparent value for you that you'll ever see over the Kenwood amp. I'd say get the Kenwood 5 channel for sure. I have a JL HD900/5 but it was about $700. I love it to death but the Kenwood is a very good option as well.

 

for the deck I would look into alpine, I've had some bad experiences with kenwood but my alpine deck has lasted 6 years. most people like to use the same brand for the system, if you can go with all jl amps,mids,highs,and sub. if you cant afford that I recommend kicker or kenwood for the mids/highs (I've listened to over 14 brands in same space before) and rockford for the amps/subs. thats just my personal preference but I will add that Ive have pretty much every brand of everything from mb quarts to rainbows,re ,kicker ,diamond ,alpine ,kenwood , orion, mtx ,rockfords ,jl, pioneer (stay away), clarion, US and so much more.

you dont need a cap, just a good battery (optima,etc..) and good grounds. your system really wont be that powerful to mess up your electric. I've got over 4000 watts with a stock battery and no cap, just fat cables.

also forgot to say you should add a pair of tweets in your upper front doors if you haven't already

 

One other thing about Class D amps (which I don't think was mentioned, sorry if it was) is that they put way less strain on your electrical system than tradition A/B amps. Manville Smith, who works for JL and posts over at DIYMA, at one time posted the differences between running two HD amps (a 600/4 and a750/1) and traditional class A/B amps with roughly the same wattage output. I can't remember the numbers, you'd have to go find the thread, but the difference in current draw on the two systems was very significant.

I've got a HD 900/5 too, and like ItalynStylion, I love mine. So much that I bought a 600/4 to pair with it when I was planning to go 3-way up front. I ditched the 3-way idea and am selling the 600/4, but the 900/5 is not going anywhere. It really makes my Hybrids sing. You can't go wrong with the HD, but that new Kenwood does look nice and a great alternative.

 

^Yes, current draw is a big plus. Class D efficiency FTW!

 

Thanks fellas.

Amp: I'm now sold on the XR-5S (I'm also sold on the JL, but the KW is less expensive...time will tell whether I made the right choice).

Class D Amps: I'm still a little blown away that an amp that small (in size) can power my whole system...crazy.

Mids & Tweets: Based on your recommendations (and my affinity to/for JL), I'm going with the JL mids and tweets. Haven't decided on C2 or C5...I'll see.

I'll update this thread in the coming months w/pics. Thanks again for all the advice!

[EDIT: 09638, I seriously considered an Alpine; but my first aftermarket HU was an Alpine; when it worked, it was the sh!t...but it had a short life, and just konked out after 9 mos or so. Anway, giving KW a try this time. Thanks nonetheless...I'll probably adopt your battery recommendation when my DieHard is dead.]

 

do you have a double cab? if not, screw rear speakers. i say in a small space 2 really nice speakers is better than 4 mediocre ones. Unless you can afford 4 great ones, just get 2.

 

Good advice even if you do have a DC. I have one set of components up front and a sub. I have no plans to install my second set in back.

 

Adding rear speakers can add depth to the stage without pulling the stage backwards, but apparently it's VERY VERY tricky to do.

I personally don't and won't run them either.

 

I have c5's and LOVE them! just FYI

 

this is coming from experience btw. same system in 2 different cars. 1st car had one pair of really nice infinity components and a sub, but when i got the taco, it was more convenient at the time to run 4 mediocre 6x8's that were lying around because they fit and required no custom work. The components sounded much better. I will eventually upgrade my head unit and add some sound deadener and will put the components in then.