Kenwood amps

I just bought a new kenwood amp yesterday(KAC-9152D)
it took a huge chunk out of my wallet (500) but i'm hopin its worth it.
I'm powering 2 MTX 6000 15's I obviously have the power to due this but i just want to know how good these amps are and if there anything i whould watch out for this.

are you sure that model number is right?

I absolutely LOVE these posts ....... don't you think you should ask about whether something is any good or not BEFORE you buy it ?

heh... I know I should have. Of course, my entire collection of sound upgrade stuff didn't even cost as much as that amp.

the reason is b/c i got the amp, but i haven't been using mono amps before and for some reason i cant get it to turn on. I dont know if you have to change the wiring or it has to be running at 2ohms to work.

the reason is b/c i got the amp, but i haven't been using mono amps before and for some reason i cant get it to turn on. I dont know if you have to change the wiring or it has to be running at 2ohms to work.
Nope, they're no different than any other amp really. Take a look at the speaker terminals to make sure that they are actually what you think they are. Sometimes they are setup a little different than regular amps. Also, make sure you have the proper power, ground, and turn on.

i took it to a pro at A&B sound (were i got it) and found out it was just a faulty amp, after I hooked up the new one, my 15's are pounding like crazy. The amp just came out in stores this week, it says 900rms at 2ohms on it but i did a power check on it and it puts out 590rms@2ohms which is great b/c my 2 subs r 300rms@4ohms.

FOR THE NEWBIES
Anyone who wants to know how to do an actual power check or the most your amp actually puts out (you can also do this at the store to see how badly you r actually geting ripped) take the total of your fuses EX. 60 and times it by 14.4 to get the MAX watts then times that number and times it by .7 to get the rms. That number will be around the actual rms due to you dont always get 14.4V of POWER.

i took it to a pro at A&B sound (were i got it) and found out it was just a faulty amp, after I hooked up the new one, my 15's are pounding like crazy. The amp just came out in stores this week, it says 900rms at 2ohms on it but i did a power check on it and it puts out 590rms@2ohms which is great b/c my 2 subs r 300rms@4ohms.

FOR THE NEWBIES
Anyone who wants to know how to do an actual power check or the most your amp actually puts out (you can also do this at the store to see how badly you r actually geting ripped) take the total of your fuses EX. 60 and times it by 14.4 to get the MAX watts then times that number and times it by .7 to get the rms. That number will be around the actual rms due to you dont always get 14.4V of POWER.


That will get you within maybe +/- 50% of the actual power output, that's about it. And you don't need to multiply by .7, that's to convert an AC voltage/current in the form of a sine wave into an rms voltage/current, the power coming from your battery isn't AC and it's not in the form of a sine wave. It's DC, so technically it's already "rms".

That will get you within maybe +/- 50% of the actual power output, that's about it. And you don't need to multiply by .7, that's to convert an AC voltage/current in the form of a sine wave into an rms voltage/current, the power coming from your battery isn't AC and it's not in the form of a sine wave. It's DC, so technically it's already "rms".

you cant measure RMS without knowing the true draw from your amps, your fuses are ridiculous benchmarks as they are only there to prevent fire. You also cannot measure against 14.4 volts because when any substantial load is placed on the electrical system most regulators will drop to and maintain 12.5 to minimize stress on the alternator.

To get a decently accurate measurement without any measuring equipment, take an ohms/ampre meter and measure the current draw while running a test tone(below 100hz for subs) and use 12.5 volts. If you have yellow/redtop or a real cap (1f @ 20v +/-10%) then you might get away with 13-14v then take 60-70% of that value to compensate for innefficiency.

You can easily find a subwoofer test tone on any p2p

*** CHEAP OHMS METERS WILL ONLY MEASURE 10-15 AMPS BEFORE CATCHING ON FIRE ***

... so ensure your ohms meter can channel the current. or get an amp meter

() I claim no responsibility for your death

Or just measure the voltage and current leaving the amp and don't worry about efficiency....and you think a capacitor would do anything for you on a test tone? haha, on a test tone it'd be even worse than not having one at all.

Or just measure the voltage and current leaving the amp and don't worry about efficiency....and you think a capacitor would do anything for you on a test tone? haha, on a test tone it'd be even worse than not having one at all.

The current leaving the amp requires a real meter... I was giving a method using only an amp meter. and no a cap wouldnt help with a test tone but it might help with scaling...

They way I was taught is what they teach you in an audio school in alberta, if you want to work in any high electronics store, or big in the industy in canada you have to go there. (simply the best).
Any you have to take you voltage in and your fuses to measure the output b/c your amp may say 1000rms but you fuses only with allow 500rms. That's why the pro's look at the fuses output first.

The current leaving the amp requires a real meter... I was giving a method using only an amp meter. and no a cap wouldnt help with a test tone but it might help with scaling...

a real meter like what?

My cheap little DMM can read up to 10 amps rms of AC current, with a 4ohm sub that's enough to measure 400rms of power, provided you had another one or a scope to measure the voltage across the terminals. More than 10 amps and you would need a clamp-type ammeter, but the same goes for measuring the power going into the amp, except if you're measuring the input side you would need a clamp-type ammeter for any more than ~80rms instead of 400rms.

They way I was taught is what they teach you in an audio school in alberta, if you want to work in any high electronics store, or big in the industy in canada you have to go there. (simply the best).
Any you have to take you voltage in and your fuses to measure the output b/c your amp may say 1000rms but you fuses only with allow 500rms. That's why the pro's look at the fuses output first.


The problem is, those fuses are slow blow. You can draw double their rating for quite some time before they'll let go, they're only there to cut the power in case of a huge surge. If you go by the fuse rating you're only going to get somewhere in the neighborhood of the right answer. Not every amp has a fuse anyway, out of the 3 amps in my car right now only one of them has a built in fuse, and it happens to be the smallest and cheapest of the 3.

Fuses=RMS that's gotta be one of the funniest things I have heard. As anyone knows, the RMS output is totally dependent on the power input just like stated above.

Back in the early days we use to use a stepup voltage regulator like what's used on Nascar. Well, you could set them up so they'd regulate a true 14v or even 15.5v. It's how pros would cheat in competitions. Most amps were rated at 12volts so you could easily double many amps' outputs by going to 15v..

a real meter like what?

My cheap little DMM can read up to 10 amps rms of AC current, with a 4ohm sub that's enough to measure 400rms of power, provided you had another one or a scope to measure the voltage across the terminals. More than 10 amps and you would need a clamp-type ammeter, but the same goes for measuring the power going into the amp, except if you're measuring the input side you would need a clamp-type ammeter for any more than ~80rms instead of 400rms.
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*me*
BAHAHAHAHAHAHAHAHAHAHAHAHAHAHHA..... ..... HAHAHAHAHAHA

before getting into innefficiency, lets look at ohms law: 400 watts RMS = 33 wattsRMS current draw. Then add into it heat and internal resistance you are def not going to measure that on a 10amp meter.

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Originally Posted by shawnwilliams
They way I was taught is what they teach you in an audio school in alberta, if you want to work in any high electronics store, or big in the industy in canada you have to go there. (simply the best).
Any you have to take you voltage in and your fuses to measure the output b/c your amp may say 1000rms but you fuses only with allow 500rms. That's why the pro's look at the fuses output first.
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*me*
ok i know some of the 'pros' you are talkin about and if I ever EVER thought of sayin somthing like that to them they would beat the crap out of me, strip my car for parts and leave me for dead in bestbuys parking lot.

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The problem is, those fuses are slow blow. You can draw double their rating for quite some time before they'll let go, they're only there to cut the power in case of a huge surge. If you go by the fuse rating you're only going to get somewhere in the neighborhood of the right answer. Not every amp has a fuse anyway, out of the 3 amps in my car right now only one of them has a built in fuse, and it happens to be the smallest and cheapest of the 3.
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*me*
automotive fuses will blow within 5 seconds at 200%, usually under 500ms. ALL amps have fuses. you cannot get anywhere within the neighborhood by fuse rating, you will be lucky to be in hte same state. If your amps dont have fuses they are either home made, kmart brand, imported equipment, made for professional use, or you are just really dumb and cant find the fuses. please list model #s and series year for reference.

ref: http://www.optifuse.com/fusesautoblade.htm


I jus wanted to add that Step up regulators are not illegal in sound competitions, no one uses them because the step up will draw more power than it produces.

BAHAHAHAHAHAHAHAHAHAHAHAHAHAHHA..... ..... HAHAHAHAHAHA

before getting into innefficiency, lets look at ohms law: 400 watts RMS = 33 wattsRMS current draw. Then add into it heat and internal resistance you are def not going to measure that on a 10amp meter.


If you'll notice, TWICE I said the OUTPUT side of the amp, NOT the input side like you keep bringing up. 400rms @ 4ohm is 10 amps, and you don't have to worry about efficiency because this is AFTER the amp.



automotive fuses will blow within 5 seconds at 200%, usually under 500ms. ALL amps have fuses. you cannot get anywhere within the neighborhood by fuse rating, you will be lucky to be in hte same state. If your amps dont have fuses they are either home made, kmart brand, imported equipment, made for professional use, or you are just really dumb and cant find the fuses. please list model #s and series year for reference.

ref: http://www.optifuse.com/fusesautoblade.htm


Forgot that the blade style fuses they use in amps aren't slow blow like the rest of the audio fuses (MIDI, ANL, AGU, etc). Of course they don't use fuses that are rated right at the amp's max current draw anyway, so it really doesn't matter. And no, not all amps have fuses. Out of the last 5 amps I've had in my car only 2 have had built in fuses. The ones that did were an Avionixx 400.2 and an Arc Audio 2100cxl, the ones that didn't were an Avionixx 800.2, Linear Power 2.2hv, and Cadence ZRS-8. And no I'm not retarded, it's not that I just didn't see them. Would you like pictures?

Linear Power 2.2hv
http://arawndark.netfirms.com/Linear_Power_22HV/index.htm
http://www.resnet.trinity.edu/areynol1/audio/lp_03.jpg
http://www.resnet.trinity.edu/areynol1/audio/lp_04.jpg
http://www.resnet.trinity.edu/areynol1/audio/installc_05.jpg

Cadence ZRS-8 (only picture I could find)
http://www.resnet.trinity.edu/areynol1/audio/zrs8_02.jpg

Avionixx 800.2
http://www.resnet.trinity.edu/areynol1/audio/amp_03.jpg
http://www.resnet.trinity.edu/areynol1/audio/amp_04.jpg
http://www.resnet.trinity.edu/areynol1/audio/avi_800.jpg

I can't see the first 3 pics, something about restricted access...

Amps look cool inside! I haven't taken mine apart yet, and I don't plan to unless it dies or something. I don't see any fuses :)

does the first one work now?

If you'll notice, TWICE I said the OUTPUT side of the amp, NOT the input side like you keep bringing up. 400rms @ 4ohm is 10 amps, and you don't have to worry about efficiency because this is AFTER the amp.

*me*
you are right, and i am right. an RMS output of 400watts on the output side might be less than 10 ampres, but its ac current and cant be measured by a simple ohms meter. and the amplifier will draw much more than 10 amps to create a 400 watt output.



Forgot that the blade style fuses they use in amps aren't slow blow like the rest of the audio fuses (MIDI, ANL, AGU, etc). Of course they don't use fuses that are rated right at the amp's max current draw anyway, so it really doesn't matter. And no, not all amps have fuses. Out of the last 5 amps I've had in my car only 2 have had built in fuses. The ones that did were an Avionixx 400.2 and an Arc Audio 2100cxl, the ones that didn't were an Avionixx 800.2, Linear Power 2.2hv, and Cadence ZRS-8. And no I'm not retarded, it's not that I just didn't see them. Would you like pictures?

Linear Power 2.2hv
http://arawndark.netfirms.com/Linear_Power_22HV/LP_Chassis_Side.jpg
http://arawndark.netfirms.com/Linear_Power_22HV/LP_Overview.jpg
http://arawndark.netfirms.com/Linear_Power_22HV/LP_Overview2.jpg
http://www.resnet.trinity.edu/areynol1/audio/lp_03.jpg
http://www.resnet.trinity.edu/areynol1/audio/lp_04.jpg
http://www.resnet.trinity.edu/areynol1/audio/installc_05.jpg

Cadence ZRS-8 (only picture I could find)
http://www.resnet.trinity.edu/areynol1/audio/zrs8_02.jpg

Avionixx 800.2
http://www.resnet.trinity.edu/areynol1/audio/amp_03.jpg
http://www.resnet.trinity.edu/areynol1/audio/amp_04.jpg
http://www.resnet.trinity.edu/areynol1/audio/avi_800.jpg

*me*

I apologize for being so condesending, and stand corrected. The linear power amp has a mag switch, which will throw when exposed unjust currents or polarity, and after looking at your website you are obviously proficient at least in car audio and deserve props. So again im sorry =(

nice pics btw

first ones work now! Excellent job with the photgraphy!

you are right, and i am right. an RMS output of 400watts on the output side might be less than 10 ampres, but its ac current and cant be measured by a simple ohms meter. and the amplifier will draw much more than 10 amps to create a 400 watt output.
Maybe all of them can't, but mine sure can, and it's just a cheap little $30 craftsman
http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=TOOL&pid=03482139000&tab=spe&bidsite=CRAFT#tablink

up to 10 amps AC or DC...either way though, you're right, on the input side it would draw a lot more than 10 amps


I apologize for being so condesending, and stand corrected. The linear power amp has a mag switch, which will throw when exposed unjust currents or polarity, and after looking at your website you are obviously proficient at least in car audio and deserve props. So again im sorry =(

nice pics btw
That's alright, and thanks. I always jump at the chance to post pics of the LP...I love that amp :)

Yeah, those good ole Linear Power amps. I loved the older ones. Man were those built to run.

I don't think any of the Linear Power amps I had had any sort of fuse but I am sure they had some sort of MAG switch or automatically resetting breaker.

its not the actual rms, is close to, due to the fuse you can only allow so much power before it blows the fuse and the amp doesn't work. And if you knew anything about it and looked on the computer of the store when buying it, it doesn't say 900rms on it like the amp it says 500rms. Even electronic stores test them that way to figure out the rms of the amp b/c they have to know when installing them that they can turn it all the way up and wont blow the subs that they are installing. Believe me I was taught by A&B sound and they are the biggest audio installers in Canada.

its not the actual rms, is close to, due to the fuse you can only allow so much power before it blows the fuse and the amp doesn't work. And if you knew anything about it and looked on the computer of the store when buying it, it doesn't say 900rms on it like the amp it says 500rms. Even electronic stores test them that way to figure out the rms of the amp b/c they have to know when installing them that they can turn it all the way up and wont blow the subs that they are installing. Believe me I was taught by A&B sound and they are the biggest audio installers in Canada.

wow, I don't even know where to begin....I guess the first thing would be to stop listening to local salesmen and installers, 99% of the time they don't have a clue what they're talking about.

the fact that your amp cost as much as my whole system makes me feel happy inside

wow, I don't even know where to begin....I guess the first thing would be to stop listening to local salesmen and installers, 99% of the time they don't have a clue what they're talking about.
Ditto. I started out in a big chain store. Man were there ever some idiots in there. They'd sell anything they could get you to buy. They didn't care about anything. Then it was up to us installers to make it work.

I'm gonna tell you that the fuses have nothing to do with the power output. It's all in the amp's design. Yeah, maybe on a Jensen or BOSS amp that power could be rated by the fuses but only because those amps suck. They have a very poor design. If you look at a Linnear Power, Orion, or even Directed Audio amps especially the ClassD amps, it's a whole new ballgame.

something kind of funny ive spent around 2k on my system. But you have to know up in here in canada is a lot more expensive.
250 Deck
170 6X9's
125 4's
300 Subs
500 subs Amp
300 Speaks amps
250 Wiring
200 Boxes

QUOTE:
the fact that your amp cost as much as my whole system makes me feel
happy inside.

What kind of system do u have under 500? You cant even get 2 type R's for 500.

something kind of funny ive spent around 2k on my system. But you have to know up in here in canada is a lot more expensive.
250 Deck
170 6X9's
125 4's
300 Subs
500 subs Amp
300 Speaks amps
250 Wiring
200 Boxes

QUOTE:
the fact that your amp cost as much as my whole system makes me feel
happy inside.

What kind of system do u have under 500? You cant even get 2 type R's for 500.

i can get type R's for $100 each, $120 for the 05 ones

not to be a dick but.. u wasted $170 on 6x9's that don't do much for your system except confuse the soundstage, $250 for wiring...? i spent $35 on all my wiring, $200 for boxes? i can buy a sheet of mdf and make a box for $30, sealed, vented w/e, $500 for an amp that i can get for $200? u paid $250 for a head unit i can get for $100

hey how come everything is more expensive up there

also, if u were around these forums a bit, i stated i was going to build a budget sq system, and i succeeded, im trading out a few parts but the cost barely exceeds $500, good huh =)

and believe it or not, ever since i bought my first head unit 3 years ago, i've taught myself how to do everything, from basic installation to fiberglassing and box making, thats how i saved alot of $$, the only thing u get from an authorized place is the warranty =P

It probably b/c winnipeg has the highest cruise night per capita in the world, and everyone has to have a system and do up there car here. So prices are pretty high b/c there is so many people do it. The actually did a movie up here on our cruise night. But the cheapest stuff you can get is like lightning audio's crap for 100$, its kind of retarded, but you want a system you have to pay the high prices. Not to mention how much used cars sell for. I bought my 93PGT for 4k. When i here people in the states get them for under a K.

And yes i know how to fiberglass and build my own boxes, and do my own installes and everything, but when you work 2 jobs its hard to make a custom fiberglass trunk.

!!!!