blackgold84

iTrader: (1)

hey every body see if you can find the hilarious fact about this amp, ill give you a hint its in the product description


sorry if this is a bad post but it was too funny for me to pass up showing every one.

see the amp here

D M N

i dont get it??

88txiroc

Man, that is funny!

Whoever buys this amp for almost $700.........had better like distortion!

10% THD!!! OMG!!!

D M N

i dont get it??

learsieglerZ'83

Professional installation is strongly recommended for this product. Please visit your local Best Buy retail store for details

why cant the customer install this one and not any other amp the sell?
and then theres the ol THD (Total Harmonic Distortion): 10.0%

GTA4ME

That's too funny!

blackgold84

iTrader: (1)

guy, i fell over laughing when i saw that, lets advertise an amp @ 2500 watts in 1 ohm (yeah right, maybe for a few seconds) at 10.0%thd, thats the highest i have ever seen in my life, gross!

to D M N,
to clear it up the thd means the amp will sound like complete crap, i think even sony's amp have a lower thd, in fact i know they do, sonys sound bad , but just imagne more thd and you got this piece of junk, they sell this crud of metal and wires for 700$, who would buy that?

NEEDAZ

“Professional installation is strongly recommended for this product. Please visit your local Best Buy retail store for details”

Big stores like that that have an install bay will almost always recommend professional installation. H*ll, I almost always recommend professional installation and I don’t install the stuff or sell it, I just fix it. It’s a way for them to CYA (cover your/there a**). You have to remember that warrantees only protect you from defects in design and/or manufacture, NOT from improper installation. Did you know that using an improper gage power wire could kill an amp? It’s to try and save them from people that don’t know things like that. Think about this, someone buys a big amp and installs it using 12 gage power wire and three weeks later the amp dies. That person then goes back to the store and gets an exchange unit for the dead one. That’s a loss for that store that they wouldn’t have had to take if they had talked the customer into letting them install the amp.

Doward

Yeah... 10% THD... funny! To give you an example, the JBL BP600.1 pushes .1% THD. That's 100x less distortion...

330hp_91RS

pretty funny... but I bet it's a typo. That's a ridiculous amount of distortion....youd almost have to try to get that much.

Anyone check any other sites for this amp to see if it says the same thing????

EDIT: checked another site....it says 0.5% THD.
that's not that bad for the brand and the amount of power it puts out.

D M N

did you really have to kill the post like that??, with your logic and well researched information

just kidding man i was thinking the same thing i mean 10% is insane i mean i wouldnt even expect that from a $25 amp from walmart

demicon

You do have a point, but think of this...

how professional are the teenage car audio installers at Bestbuy or other such stores going to be?

LOL

Granted there are some damned good installers that are teenagers, but for the most part, there is very little education or training that would go into such a position for these kinds of stores.

blackgold84

iTrader: (1)

i feel when it comes to installing stuff i want to do it, just because i have so much dang fun doin it. other may not feel the same way(or dont want to break any thing...) but i will say this about best buy and comparable stores, they may not be 100% professional but they have installed many many amps and subs (unless they are new) i generaly feel they can take care of it for the people that dont want to do it themselves, but that doesnt make them very good at it, its like by default they get the respect from me, hehehehe . i would say that if you could do it and put it in yourself, go for it because the extended warrenties those places carry count wether or not they install the stuff.
my 2 cents...

2 dope

anyone have this amp, is it good?

D M N

$700 for a amp my whole system wont even cost that much

2 dope

what system you gettin?

D M N

check my post

https://www.thirdgen.org/techbb2/sho...hreadid=196660

Pioneer DEH-P47DH 1.5 Din Headunit - $162
Pioneer TS-A4657 2-way 6X9 - $47.70
Pioneer TS-A6970R 3-way 4x6 - $54.00

Total - $263.70 (w/o S&H) (ikesound.com)

JBL BP600.1 600watt amp - $175.50
1 - Pioneer TS-W384DVC 15" subwoofer - $90.00
Lightning Audio sxpk4d 4 guage wire - $62.10

Total - $327.60 (w/o s&H) (ikesound.com)

I'm still up in the air about the 15"

I'm thinking about maybe
2 - Kicker Comp C12-4 12" -$108
or-
2 - Pioneer TS-W34C 12' - $90

aaron7

iTrader: (7)

Not to mention, that brand sucks big time lol

I made the mistake of buying 300 watt Power Acoustik 6x9's with like 10lb magnets on them at a yard sale for $10... yah they weren't even worth that much, stock was 100x better

spartyon

well you did buy them at a yard sale,

aaron7

iTrader: (7)

New in the box, might I add lol

hydric

I could take a big fat dump in the john, leave it for 5 weeks and tell someone its new.

The point of amater sellers is to get rid of their crap, whatever means necessary.

Everything on Ebay that says (never opened, never used) is hard to believe sometimes.

Motto: Lets make money, money, money, money.

aaron7

iTrader: (7)

Very true, but this was sealed.


I see that on ebay all the time, something has been cleaned up really good and put back in the box, and they say, I took it out once to test it... that's all. Why the hell would you need to test something that is new? Unless it's crap to begin with lol

2 dope

so is buying off ebay a bad idea? I like my sub that i got. I know its used but hey not a bad price.

hydric

heavens no, I buy alot of things from ebay.

from cds to graphing calcs to transmissions. I just used it as a cheap example that your liable to get screwed by the moto "I swear its new, i only opened it to look at it" bs. Used is good too

Ebay is powerful :hail:

Christos

Uh, why would running a smaller wire (bigger gauge) 'kill' an amp?

At the worst, it wouldn't provide enough power for an amp (like running a 12 gauge wire for say, a 1,000 RMS amp)

lykan

Well it does make a difference.. it has to do with the way electricity works.. if electricity has a hard time getting where its going (resistance) it likes to make heat, and heat is an amp's worst enemy.

The longer and the skinnier a wire is, the harder it is to get the amount of electricty you need to he end of the wire.

For example in construction we used compressors which draw a lot of power, if we used a skinny electrical cord, we could burn up a compressor in one day the longer the cord, the worse it was. You could hear the compressor struggle oto start..chug chug. and it would get 10x as hot really quick..

with the same length of cord but a heavyier guage, we had no problems at all.

So an amp that draws a lot of power, hooked to a skinny cord works like this.

The more it pulls, the less the power wants to go through that skinny pipe. It just can't get all that power through that skinny wire, so it heats up instead.

One more example, heaters..they use a very skinny uninsulated wire in very long lengths.. the power has a hard time going through those skinny coils, so it makes em get red hot instead..that same power goes through the big fat in wall wires and doesnt heat up a bit, because there is enough room in the wire for the current.

TomP

I don't really think you can compare air compressors to car amplifiers; an amplifier has no mechanical parts. It might hurt a motor to run on low power, but an amp will just go into distortion due to a voltage drop.

I'd think you'd have to be more concerned about a small power wire catching fire, which would destroy the amp because of the car blowing up.

da BEAST

Wrong!!! What lykan is talking about has to do with resistance and Ohm's law. Remember from school. Wires are, of course, like pipes; current is like the rate of water flow (gallons per minute); and resistance is like friction in the pipes. Electrical resistance is friction in the wire. Just as friction can get something hot, so can the electrical resistance result in the wire getting warm or even hot enough to glow. The amount of heat is proportional to the diameter of the wire, its material and thus resistance, and the current. The thinner the wire, the more electrical resistance. This is because it is more difficult for the electrons to pass through the wire. It is like there is more "friction" in the wire. That is why a thin wire is used in an electric light bulb: it has more resistance and gets hotter faster.If the gauge is too small for the power of your amplifier, you will blow fuses or even worse melt the wire or fry your amp.

lykan

Da beast explained it well Although I was talking about compressors, they may have mechanics involved, but the principal is the same.
Any electrical component drawing power when faced with too small of a supply wire will produce heat, and in some cases way too much for your mosfets.

I didnt know anythign about elctricity and wires until i ran across the problem myself, So I went out and reasearched and da Beast's explanation is the conclusion I came to.

NEEDAZ

To small of a power wire CAN kill an amp, not right away, but over time. It will seriously shorten the life of an amp.

This is going to be long. I’ll try to keep things in there simplest terms and be as detailed as I can without going overboard.

It works like this. Your Car audio amps have a switch mode power supply in them that will supply +40Vdc and –40Vdc. 40Vdc is just an example. It can range from +30Vdc-30Vdc to +70Vdc to –70Vdc. To step the 12Vdc it uses switching transistors (FETs) turning on and off vary fast to make AC (really pulsating DC). It dose this at about 25,000Hz (25kHz). Three reasons for the high frequency. One, 25K is above the human hearing rang. The second and MOST important is that at that high a frequency the transformer and filter components can be much smaller. Third, switching supply are VARY efficient.

OK, so now we have AC (really pulsating DC), with AC we can use a transformer to step up the voltage (remember that a transformers will not work with DC). Ever look inside your amp and see a big donut looking coil of wire? That’s the transformer. Then rectify and filter the AC and where back to having DC but at a higher voltage. That’s how you get a positive and negative voltage that is more then the 12Vdc supplied.

The switch mode supply will also monitor its output voltage so it can regulate it. EI: there’s a big base hit, that’s more drain on the supply, it will then do what it can to keep the output voltage the same.
How’s it do this? The switching controller (small IC that control’s the operation of the power supply) will vary the duty cycle of the switching transistors. The duty cycle is how long their on Vs. how long their off. The more their on the higher the output voltage, the shorter there on the lower the output voltage. So when the big base hit comes in, the extra load on the supply will pull down the voltage of the supply, the supply see this and increases the duty cycle of the switching transistors to bump the output voltage back up. When the load drops the supply will drop the duty cycle back down. This all happens in a fraction of a second. That is why switching supply are so efficient. Now if the supply has less voltage as a source, it will also increase the duty cycle of the transistor so that it can keep the output voltage at whatever voltage is should be.

Now the important part. To small of a wire will develop a higher voltage drop back to the amp. So when the amp needs all that power from the supply for that base hit, It can’t get it because of the high voltage drop from the wire give the input less then it’s 12Vdc. So it has to work that much harder. So not only is it working harder because of the extra load on the supply, it also has to make up for the lower input voltage.

This increase in duty cycle means the switch transistors are working even hard and generating more heat. We did a test on a Pioneer GM-X962, an amp that is notorious for this type of failure. First we ran the amp at 12.5V for 10 min. and measured the temp. of the heat sink near the switch transistors, six of them in this amp. Than we dropped the input voltage to 10.5V and let it run there for 10 min. The temp. had increased a little over 40dF. I can’t remember the exact temps, just the difference. That is a considerable increase.

So, what dose all of this mean for the life of your amp. HEAT KILLS TRANSITORS. May not do it right away, but it dose shorten there life. That’s why the heat sink is as big as it is (the enter case of the amp). To help keep things, the components of the amp, from over heating. So that amp that lasted two years may have lasted TEN YEARS, if kept cool. Two Vs. TEN. Heck, if the amp gets hot to the point it’s uncomfortable to leave your hand on it, it will probable only lest a mater of HOURS.

Now keep in mind that in the cheaper amps, to keep cost down they don’t “over build” their units, to keep cost down. Part of what your paying for in the higher price amps are parts that can work longer at higher temp. Parts that can handle more current. Or a unit that is “over built”.

As for voltage drop always causing heat, not entirely true. If you have a non-active load the voltage drop will cause LESS heat. Less voltage to load = less currant = less power, power is heat. With your compressor, with less voltage the motor will spin slower. The motor turning slower means that the windings of the motor have power to them LONGER. Again, this makes heat and heat is BAD.

Jim85IROC: I always screw something up when I try to type out a long explanation. How did I do?

KCobain147

Another fun simple way to explain it is go for a run, with your nose plugged breathing through a straw, tell me how you feel when you're done. Thats' your amp using a 12 gauge power wire. Now run again with your mouth open. To your amp that's a 4 gauge power cable. Simple.

blackgold84

iTrader: (1)

i love that explaination, the best on i have heard so far.

TomP

Well, yes, I know about thinner wires and resistance and heat and etc. ("Why did my car catch fire? I used a 10ga wire on a 300 watt amp!") But I didn't see how it would affect an amp's longevity (as opposed to sound clarity)... NeedAZ cleared it up here:

Never occurred to me that the power supplies would work to raise voltage up! I figured if voltage dropped, the whole p/s output dropped, and that was the end of it. Which, is true to a point, output will drop, but didn't figure on "extra work" by the fet's.

Thanks!