help me pick a new head unit and speakers please!

If you choose those 2 ohm Kappas, I would go with a low-power, external amp, unless your head is specifically rated to drive 2 ohm loads. This is because your 22W/channel (4 ohm) rating becomes 44W/channel when driving the 2 ohm Kappas. When turned up, you will be asking a lot more from your head unit than if you were using traditional 4 ohm drivers. This will cause your head to run hot or shut itself off. It all comes down to how beefy your head unit's internal power amp is.

BTW, 2 ohm component speakers are relatively new. The reason they exist is because you can extract more from a head unit's power output than 4 ohm speakers do. The home audio standard is 8 ohms. Using 110vAC, you can make lots of watts through 8 ohm coils, but 4 ohm was originally adopted for cars because of the 12-15vDC voltage, which limits the power output. Using ohm's law, we can see how an 8 ohm speaker can only pull a maximum of 18 watts max from a 12 volt power source.

I = V/R (current = volts/ohms)

So...

1.5 amps = 12 volts / 8 ohms

Amps can then be used to calculate power in Watts using this formula:

P = VI (power = volts x amps)

So...

18 Watts = 12 volts x 1.5 amps

Note this 18 watts is TOTAL for all for channels driven, so for a 4 channel amp, you can expect 4.5 Watts of honest power per channel into 8 ohms with all 4 channels playing. This isn't enough to get loud in a car with all the other road noise, so the 4 ohm speaker was born.

Doing the same math as above with 4 ohm values, you get the following:

3 amps = 12 volts / 4 ohms

36 watts = 12 volts x 3 amps

Using 4 ohm coil drivers in a 12 volt system, you will get a max of 36 watts, or 9 watts per channel into 4 channels. This is about what our stock head unit is rated. In fact, most all heads used to be rated around this value.

But something happened to aftermarket head unit power specs about 15 years ago. Suddenly you could have 20, 30 , even 50 watts coming out of a 12 volt system. It seems impossible because of Ohm's law, but because most 12 volt systems actually operate closer to 14 volts, you can get a little more power. Using 15 volts, about the max possible in a stock car, a 4 ohm speaker pulls 56.25 watts, or about 14 watts per channel into 4 channels. So the head unit makers decided to rate their power outputs based on a 15vDC power supply. With the car running, and throttle at WOT, you might actually see this kind of power.

Furthermore, many external amp manufacturers found that their power ratings would be doubled for a few milliseconds during burst tone tests. This had nothing to do with real-world music, but in fact using capacitors to stiffen the power supply, they saw "peak" power close to double their rated power, so they used these for advertising purposes. Following suite, "peak" power was soon used by head unit manufacturers to inflate their max power from 14 W/channel at 15V to 28 W/channel "peak". You saw numbers like this for a while starting in the '90s, and it even continues now: 20 Watts x 4 or 25 Watts x 4, shown as peak power on the packaging. It was kind of possible in a lab, but not realistic for listening to music. The actual power, known as RMS power, was still in the 10-14 Watt range.

Finally, as head units battled for power, a few companies figured out that if you drove only one or two of the 4 channels, you could see a much larger power number from a head unit's internal amplifier. Driving only two of the four channels, you could see 28 Watts RMS (about 56 Watts peak) to each of the two speakers. Now you could advertise a head unit that puts out 22-28 watts "RMS" into 4 ohms with a 15vDC power source. The RMS spec was important, because the public became aware of bogus "peak" power ratings, and RMS sounded more legit. However, these new RMS ratings were only with the 2 front channels driven. In theory, you could advertise 50+ Watts per channel RMS with only one channel driven, but this is far-fetched because you cannot call the head unit "stereo" in this case.

So the point is, most head unit manufacturers are liars. They boost advertised power ratings using unrealistic system voltage, the publishing of "peak" power numbers, and the assumption that only the front two channels will be used. It's bullshit, because the average customer listens to all 4 channels and is actually getting 10-13 Watts of real power. Sad, but true, and it has been proven. Ohm's law doesn't lie. There is also no standard or regulation by the FCC on car audio specifications. You see the same bogus ratings happening with amps and speakers. The honest specs are there if you know what to look for, but most folks want to believe their unit does what it claims.

Fast forward to the mid 2000s. somebody out there decided to be honest and build a head unit stable into 2 ohm loads. Here's the math for a speaker with 2 ohm coil:

6 amps = 12 volts / 2 ohms

72 Watts = 12 volts x 6 amps

Actual RMS power into 2 ohms is now 72 Watts, or an honest 18 watts per channel... NOW we're talking. This is enough to do some real listening at reasonable levels.

GM used 2 ohm speakers to extract higher wattage from the Monsoon system, and now speaker manufacturers are adding 2 ohm drivers for the same reason. Trouble is, it's a tough job to produce this kind of power, and not all heads can do it.

So, why are external amps so much better? It's simple. They use transformers in their power supplies to step up power rail voltage to 20 or 30vDC, so aren't limited by the 12 vDC system. My a/d/s Power Plate is rated at 25W RMS x 6 channels at 12 volts, with all channels driven. THAT's honest power. This little monster is also 2 ohm stable, so it can drive all six channels with 50 Watts RMS each, with the car turned off. Using "peak" power ratings, my 25 x 6 amp will make somewhere around 300 Watts. with the alternator spinning, quite a bit more. This blows a head unit away in all respects. It's why you pay more for external amps. It's also a big part of why they sound so much cleaner and louder.

To answer your question: don't buy the 2 ohm Kappas unless your head is 2 ohm stable, and you want to put it to the test (it'll run hot!). I wouldn't, personally. If you buy an external amp, you won't need the 2 ohm speakers. You could go with the 4 ohm Kappas and be fine. Same price, same sound quality, and you will not be straining your amp to drive the 2 ohm load. If you do use the 2 ohmers with an external amp, expect the Kappas to get pretty loud. I don't see why you'd need to do this, but you could. One good reason is when using a very low-powered amp that's stable into 2 ohm loads. You can get double the power by using the 2 ohm coils.

check out ebay they have a ton speakers and components for cheap. but if you do go with a 2 ohm speaker i would spend the extra money on a set of components. you get a better sound quality from them. here is a link for a good novice set of mb quartz components i found on ebay....only if i had $100.

Link

you would have to get a seprate amp to drive a sub and a speaker. if you go with an amp and sub combo, you want to match rms of both. say you get the jl 500/1 rated at 500 watts rms, then you would want to find a sub rated at the same. i say the best way to do it to achieve more power would be if the sub was rated at 1000watts @ 4 ohms rms you would want to find an amp that is rated at 1200 watts rms @ 4 ohms. the sub can hadnle a lil more power than what the rms rating is but you dont wanna push it to its max power cause you will run the risk of blowing the subs. i wouldn't advise on switching this method cause if you get a sub rated at 1000 watts rms and you get an amp rated at 500 watts rms. the subs will try to suck more power from an amp cant produce no more power and run the risk of blowing you amp. an amp is more expensive to replace versus a sub.

again myself, i want more bass so im saving for a jl 1000/1v2(a phuckin beast) amp and 2 jl 12w7. plus a ton of dynamate stop my car rattling all over the place.i know a jl 1000/1v2 costs $700 or more and the subs run about $300 more. but the power and the clarity is worth it. i phuckin luv jl products every since i heard them compared to an alpine v12.no competition. but alpine v12 are great for digital clarity and 5.1 surround.

So are we saying that the 2ohms will be bad for the stock head unit. I got to replace my rear speakers they are horrible. I wanted to get these but if they won't work well with the stock head unit what do you suggest. Not trying to steal a thread here.

I'm saying 2 ohm speakers aren't the best idea unless your head unit is designed to drive 2 ohm loads safely. It could run hot and do damage if you really crank it. Check your receiver's specs to know if it's a good idea.

What you'll notice about the 2 ohm speakers is that they get louder with less volume level, so be careful with the knob. You can probably use the 2 ohms safely if you don't turn it up all the way.

I decided to include a small amp. Wish I had paid more attention, I got the newer Alpine model of the one bigbad is selling. It's a 200W 50Wx4, perfect for the Kappas which are 55W.

Everything is ordered... I'm fixing up my old HVAC head and dash teardown day, here I come!!

I think you'll like this set-up. Those 2 ohm Kappas will pull more than 50W each from your amp. No problem though, just turn down your gain controls. Turns it into a 25W x 4 amp.

Next you'll want a modest sub in the trunk.

AA wrote:

Next you'll want a modest sub in the trunk.

In the old days I would have, but my tastes have changed. I love the bass, but it's also a family car...

I love the eclipse unit I put in my riv but man, that Pioneer blows it out of the water in form and fitment... I may have to swap out as soon as I can either A: Afford to buy it and the sirius unit up front, or B: go w/out a system for as long as it takes to sell my current eclipse head unit and integrated sirius unit.

Oh, as far as Sirius goes, I would never recommend one of the built-in units. The Starmate (and some of the other standalones) has more features, including a wake-up alarm, which is awesome. I have my Sirius turn on at 7:00 AM, then when I leave for work 30 minutes later I have 30 minutes of rewind already, which is just too cool. The artist/song alert and rewind are too cool to give up.

I know some of the built-in units have rewind and artist alert now, but I still don't know of any that have wake-alarms.

Heh... well, I don't sleep in my car and I really don't get many opportunities to listen to music at home.

Is this too good to be true. I think this would go very well in the riv. I have looked online and this is the cheapest I can find it for. Does anyone else think this price is to good to true?

http://www.86photovideo.com/products.asp?dept_id=10410&product_id=18902

Or even this one

http://www.86photovideo.com/products.asp?dept_id=10410&product_id=18812&show=accessories

This is the one I would probably get since it plays dvds. I do not go a lot of place that I need a nav system for. But I think playing dvds would cool. I just do not want to get ripped off by buying from a less know vendor.

On ebay that got indashs pretty cheap
I Just Got A pioneer ffrom my brother inlaw he is district manager at best buy so i told him Hey I need this, Ok Now its open box item and dirt cheap

I guess I more concearned about why they are so cheap compared to others that sell that same model. I do not want to get ripped off anywhere every here of this store before.

That stuff marks up quite a bit at retail. I don't think that kind of difference in price is unexplainable. Go for it

Im going to give it a chance then i got can finally get everything going. It will be different listening to cds in the riv for sure.

http://www.86photovideo.com/products.asp?dept_id=10410&product_id=18902

Damn can't see how you guys spend so much money on that stuff. It looks nice and that's a good savings but it's still damn expensive. If I'm spending that kind of money on the Riv it'd be in performance parts or noticeable external cosmetics.

I have always had a thing for stereos in cars to me they are better than performance and comestic mods. Also its pretty cheap I am doing pretty good right now got a good job and just me to support.

Shintsu wrote:

Damn can't see how you guys spend so much money on that stuff. It looks nice and that's a good savings but it's still damn expensive. If I'm spending that kind of money on the Riv it'd be in performance parts or noticeable external cosmetics.

to each their own....

With my firebird I try to spend it evenly... on performance first, then cosmetic. Ive only spent 65$ on interior stuff... that would be a used OE cd player from a 01' Trans am, my formula came with a tape deck, and im not a fan of aftermarket stero's in those cars.

my riv has a 350$ kenwood deck, but it came brand new installed when I bought the car for 750$, is also has aftermarket speakers of some sort. Sure it sounds good, but spending that much myself, I never would have.

Shintsu wrote:

Damn can't see how you guys spend so much money on that stuff. It looks nice and that's a good savings but it's still damn expensive. If I'm spending that kind of money on the Riv it'd be in performance parts or noticeable external cosmetics.

I justified my system because the factory tape deck was jammed, and the CD player was tripping out. I wanted to upgrade. After listening to my system for a few months now, I can't believe I waited this long. The improvement is... drastic...

deekster_caddy wrote:

...., I can't believe I waited this long. The improvement is... drastic...

I'd also like to go aftermarket, but I'm afraid of what kind of figures I'd be looking at. I would NOT do the install myself.

I've got over $900 in my audio system, and still using the factory head. I like these double DIN pioneer units, though. Nice look for our dash.

Good enough reason Derek, but honestly how can the head unit change the actual sound that much? In a car, I thought speakers were paramount to sound quality.

AA, that's crazy. At best I could see myself having that much worth of home audio equipment (At some point, not now) but not car audio. My home audio is at far less risk of being stolen and much more appreciable and varied due to a large selection, literally no installation (Not like taking the dash apart or the door panels) and good deals on stuff people don't realize are good (Little old lady selling her husband who died's audio stuff because she won't listen to it and has no idea what it's worth).

But as was said, all in preference. That's just a lot tied up into that part of the car. I'd have to have more money tied up in the motor or something beforehand.

I also look at it like this. I can take all of this with me to a different car. If I did a lot of performance mods they will not really be able to come back out of the car. Car audio I think holds better value for that transplant ability.

I do have more money in the motor, so it's all relative. Since I have at least $5000 investing in music media, the cost of my play-back system seems small.

I bought all of my equipment used on ebay - over a period of time. I totaled up the value of the equipment once, it was over $3k retail. Been in the car 5 years, parked on street every night, never had a problem. Note that I do not have tinted windows nor aftermarket wheels.

It really depends on how important music is to you, and how much time you spend in the car. I drive about 75 miles every day, so that's almost 2 hours that I can use to enjoy quality listening. That's my sit-down time. Some people lounge in front of the tube, some surf the web; I listen and drive.