SOULMUSIC

iTrader: (8)

Like many, I`ve spent many many hours searching for the best deal I can find on larger amplifiers..

I think I understand what is important as far as statistics for amps and what those stats actually do when it comes to the music.
S/n ratio, damping factor,efficiency etc

I was very interested in the Cadence ZRS7 , 18 volt capable, 100DB S/N ratio, dual 0 awg power and ground , requires 2x 200 amp fuses etc etc...7000+ watts RMS it claims.. WOW... but

Then I noticed the Soundstream DTR2200.1 ... 4 gauge power/ground, no 18 volt, lower S/N etc..but it says it requires a 200 amp fuse also..

Soooo.

The Cadence claims 7000+RMS watts on 400 amps of fuses for $1000+
The Soundstream claims 2200 RMS watts on 200 amps of fuses for $260+

Both are class D with efficiency ratings at least similar.

I know alot of the guys with big and bigger amps don`t even run fused, BUT.... Does the fuse size actually indicate anything

AAAAAAA

iTrader: (7)

No it doesn't but we all use it anyways for a ruff idea hehe.
200amps x 14.4 volts = 2880watts at 100% efficiency.
if an amp is more or less 70% efficient it would do 2000watts.

A few other things... being able to run at 18volts isn't a plus for daily driving. you can't control votlage unless you do major electrical upgrades hehe. this would be for SPL dedicated vehicules only IMO.

Laslty damping factor is a non factor.
SN can only be compared within the "same brand" or between CEA rated products.
Efficiency is another thing that can probably just be compared between products in the same brand as companies will measure that differently to.

vrdublu

iTrader: (5)

I'll start by saying that most amps are over fused to begin with but a fuse rating does tell you the amount of draw it's capable of to a degree. You can not draw 200A of a 4 Gauge wire, you will fry the cable if your amp is capabale of those kinds of current draws. I believe max draw on a 4 gauge is around 150A-160A, google it to be certain. Length of wire also determines the gauge of wire required, although for car audio it makes of little significance for the most part. Class "D" amps will require alot less current as they are more efficient then the A/B counterpart. There are amps that don't use internal fusing and rely on battery fusing only for protection, others that use internal fusing will also require an external fuse at battery for safety reasons. Normally if I use an amp with internal fusing I will use 80% of that as my battery fusing. Hope this answered your questions for the most part. If you do the math, the Cadence amp appears to be a little more truthfull about it's specs.....

SOULMUSIC

iTrader: (8)

Yeah....lol..do the math..rrrrrrrrrright

I can`t seem to make any numbers make sense.

This site: http://www.rbeelectronics.com/wtable.htm says

- 4 gauge can carry 200 circuit amps for 15 feet!
- 200 circuit amps = 1200 circuit watts

So that site says the Soundstream could draw its 200 amps through a 15 foot 4 awg wire, but 200 would only be 1200 watts!!
The Cadence could only do 2400 watts!!

Thats messed up bro, so I check another site .

This one : http://www.the12volt.com/info/recwirsz.asp says

- 188 amps = 1400 watts (so 200A would be about 1500w)
- 4 awg carries 150 amps max

Sooooo UM yeah, now the Soundstream can`t draw the 200 amps and again the Cadence is still way off rated power.

Next!!

this one : http://www.powerstream.com/Wire_Size.htm

WTF 4 awg good for 60 amps!!!.. It does have a handy voltage drop calculator ( BUT is it true)

No numbers are consistent with any of the others!!

More money = more power.. There`s the only math/science that seems consistent.. Oh... Pay to Play too..

vrdublu

iTrader: (5)

The thing about the Cadence you're forgeting is that it will run on 18V with 2 x 200A fuses. Which will end up being 7200W, realistically this will not happen of course being that the amp is probably 60%-70% efficient and you could not draw 400A without blowing fuses, not to mention the (10) batteries and (2) high ouput alternators required for this sort of venture. So that would be 4320W-5040W Peak output. Than consider the fact that RMS will be approximately half of that 2160W-2520 at best, as the more power you draw the more power is wasted as "heat". And if you want true continuos power output take another 50%-60% off that again and you will have a true realistic output of an amps capability for all day music playing 1296W-1512W. But at least when you're not "burping" or playing music insanely loud you could always fry some bacon and eggs on that ****.
This of course is just raw numbers based on class A/B topology and without actually reading everything there is to know about the amp, but I bet I'm not that far off.
Class "D" will do a bit better than that, but do you really need that much power? Every manufacturer will play with numbers and try make their product stand out without telling you the whole truth, and sometimes the lines become very blurred.

SOULMUSIC

iTrader: (8)

yeah, really blurred..

I don't NEED the power but want it.
We had a hell of a wakeup when our 2-12s on 2 k only did a 135db on music in the van another 2k, new box and or another sub should help get us into the 140s we're hoping

I really better get to reading more

JohnVroom

... build correctly and you should already be there (assuming the woofers and the amp are quality and designed for SPL)

make sure you have the electrical system that can handle the power, build the box correctly, and locate it correctly in the car and play a song that hits your peak frequency

SOULMUSIC

iTrader: (8)

US amps xt2000d x2 , 2x frankenwoofers 1500wrms, prefab box

Yeah, we have alot of learning to do.
Your probably %100 right John...We should be at 140..
We have some ideas that don't include added gear.
We should have an aftermarket battery by now, we don't. We're till running only a single 0 aluminum wire run to the back, should upgrade to copper.
Our box is on the small side for the subs, need another cube or 2.
We're firing forward because the box was too deep and too close to the hatch to allow proper loading off the back. A new box will hopefully fix that.

Maybe a 140 with those things done, and some more tuning?

Still getting more cone and power though

SOULMUSIC

iTrader: (8)

I found this post about the Cadence ZR6(not zr7)while hunting around...
Impressive if he's on the level...

" I know this is a 3 weeks old thread, but iīm posting here to give a couple of reviews about my amp. I bought the Cadence ZRS C6 and let me tell you something, itīs great!! The C5 specs are at 16 volts because itīs a new prototype or something like that, but the ZRS C6, itīs 6000 rms @ 1 ohm 13.8 volts, i clamped my system with a 40 hz tone and it gave me 4283 rms @ 2.45 ohms , then, i played a 55 hz tone and it gave me 2728 rms @ 3.95 ohms , and i only got a kinetik HC1800 battery and a 140 HO alternator, you can imagine that, with the 40 hz tone my current got to 12.9 volts!!! "

wow...
So what does this tell someone who actually KNOWS how things work

Car stereo math, I have a solid F average..

JohnVroom

find your peak frequency then change ONE thing at a time find a tenth here and and a tenth there and you will be where you want to be. often doing things that shouldn't work and kind of oppose common sense work in SPL.

The key to this is changing one thing at a time, start with a strong electrical as it is the foundation