#241880 - 18/11/2004 15:55
Deciphering Amp specs
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old hand
Registered: 15/07/2002
Posts: 828
Loc: Texas, USA
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I was perusing Phoenix Gold's website the other day and ran across this amp. It's a 6 channe, 5x50 + 1x100 designed for in car theatre. What do the IASCA specs mean? If I'm reading this right, does it mean that if voltage drops to 12.5 volts then the amp is 18x5 + 36x1 or does it mean that their RMS numbers at 14.4 are BS or both? What voltage are amps typically quoted a...13.8v? The footprint and the digital input seem to make it a good fit for an empeg with one of Stu's sound cards, no? R5.1 Mobile Theater R5.1MT FRONT, REAR AND CENTER CHANNELS:: INTO 4 OHM STEREO AT 14.4 VDC (MAX POWER) . . .. . . . . . . . . . . . . . . . . . .100 X 5 INTO 4 OHM STEREO AT 14.4 VDC (RMS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50 X 5 INTO 4 OHM STEREO AT 12.5 VDC (IASCA) . . . . . . . . . . . . . . . . . . . . . . . . . . .18 X 5 SUBWOOFER CHANNEL INTO 4 OHM AT 14.4 VDC (MAX POWER) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .200 X 1 INTO 4 OHM AT 14.4 VDC (RMS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100 X 1 INTO 4 OHM AT 12.5 VDC (IASCA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36 X 1
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#241881 - 18/11/2004 20:39
Re: Deciphering Amp specs
[Re: Mach]
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pooh-bah
Registered: 16/04/2002
Posts: 2011
Loc: Yorkshire UK
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I think that the long and the short of the spec. is: Do you want to go deaf before your time or die being distracted in traffic?
_________________________
Politics and Ideology: Not my bag
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#241883 - 18/11/2004 23:35
Re: Deciphering Amp specs
[Re: Mach]
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new poster
Registered: 23/05/2004
Posts: 15
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Right Iasca specs are for when the amp is in a sound-off competition using iasca rules, and they declare what power the amp is, so smaller is better. For actual power output, take the RMS value, realise that by the time the power gets to the amp its never 14.4 volts and is usually slightly under 12 volts unless your using power caps. So RMS value devided by 14.4 then multiplied by 12 will give you a real power output. Unfortuanely PG are one of the only manufacturers who give real power outputs anyway, must use peak power levels which are a load of BS. Quickest way of finding out how powerful an amp really is: Total ampage allowed by the fuses. Example a amp with 2x20 amp fuses is a 40amp amplifier and will give a maximum output of about 480 watts rms.
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#241884 - 19/11/2004 04:30
Re: Deciphering Amp specs
[Re: scollinguk]
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old hand
Registered: 15/07/2002
Posts: 828
Loc: Texas, USA
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Ok, so from the same specs, the amp needs a 30 amp fuse. 30x12 =360 which is close to the 50x5+1x100 rms value quoted previously. Thank you for the explanation.
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#241885 - 19/11/2004 05:28
Re: Deciphering Amp specs
[Re: scollinguk]
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carpal tunnel
Registered: 20/12/1999
Posts: 31597
Loc: Seattle, WA
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Quote:
Total ampage allowed by the fuses. Example a amp with 2x20 amp fuses is a 40amp amplifier and will give a maximum output of about 480 watts rms.
I'm no amp expert, but this sounds like complete hogwash to me.
Fuses are meant to prevent a fire if the power wires get accidentally grounded. So although the fuses must be above the maximum current draw of the amplifier, I don't think that translates directly into the amount of sound output you get at the speakers. Those fuses could be almost any value above the max current draw.
Can anyone who actually is an amp expert definitively confirm or deny the "fuse rating indicates amp performance" theory?
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#241886 - 19/11/2004 06:15
Re: Deciphering Amp specs
[Re: tfabris]
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journeyman
Registered: 04/05/2000
Posts: 84
Loc: Australia
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Quote:
the fuses must be above a the maximum current draw of the amplifier
Your right there will be headroom in the fuse rating for sure, you don't want the fuse to blow every time you turn the volume up.
Also amps are not 100% efficient. The power warming up the heatsink is not going to the speakers!
Rod.
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#241887 - 19/11/2004 11:27
Re: Deciphering Amp specs
[Re: tfabris]
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old hand
Registered: 01/10/2002
Posts: 1039
Loc: Fullerton, Calif.
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In general, engineers will size the fuse to be the maximum load x wiggle factor. However, many will size the fuse based on the lowest current capability of the components. This means that if an amp draws 5 amps peak during operating, but the smallest component won't burn at 10 amps, the fuse will be 10 amps.
Efficiencies of amps varys widely, too. I've had a few amps that made better heaters than amps. Once I had a Delco amp that, insanely, drew maximum amps at 0 volume, and dipped inversely to volume! (I think this was done to compensate for the crappy Delco speakers that would buzz if hooked to a normal amp. The stereo would retract the speaker cones to maximum and operate them inversely to normal systems. It did sould nice at low volumes.)
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#241888 - 19/11/2004 18:38
Re: Deciphering Amp specs
[Re: tfabris]
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new poster
Registered: 23/05/2004
Posts: 15
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Quote:
Quote:
Total ampage allowed by the fuses. Example a amp with 2x20 amp fuses is a 40amp amplifier and will give a maximum output of about 480 watts rms.
I'm no amp expert, but this sounds like complete hogwash to me.
Fuses are meant to prevent a fire if the power wires get accidentally grounded. So although the fuses must be above a the maximum current draw of the amplifier, I don't think that translates directly into the amount of sound output you get at the speakers. Those fuses could be almost any value above the max current draw.
Can anyone who actually is an amp expert definitively confirm or deny the "fuse rating indicates amp performance" theory?
Apparentlly no amp expert and no expert at reading either, i said by the fuse rule i said the MAXIMUM output of the amp would be the total fuse rating multiplied by about 12 volts, if this isnt correct please explain how the maximum could be any different apart from increasing the voltage which is nothing to do with the amp itself. Cheerfully look forward to your reply.
Also fuses are not only made for preventing fire if the power cables earth, i am not going to explain all the reasons for fuses as there are so many, but all i can say is that by that statement you are showing you naivety.
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#241889 - 19/11/2004 19:03
Re: Deciphering Amp specs
[Re: scollinguk]
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carpal tunnel
Registered: 20/12/1999
Posts: 31597
Loc: Seattle, WA
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Quote:
said by the fuse rule i said the MAXIMUM output of the amp would be the total fuse rating multiplied by about 12 volts,
Right, and I'm saying that the amp's maximum output is probably a lot less than the fuse rating. Stated another way, the fuse is most likely rated for a much higher amount of current than the amp can draw. That's on purpose, so that the fuse doesn't blow accidentally.
I'm just saying that, at best, looking at a fuse is a highly inaccurate way to determine the capabilities of the device that the fuse protects.
Quote:
Also fuses are not only made for preventing fire if the power cables earth
Agreed, they are also made to protect the amplifier's internal components from problems, and to protect the car's electrical system from shorts in the amp itself.
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#241890 - 19/11/2004 20:03
Re: Deciphering Amp specs
[Re: scollinguk]
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enthusiast
Registered: 08/08/2000
Posts: 351
Loc: chicago
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Quote:
maximum output of about 480 watts rms.
You wrote it once, and quoted it again. It's the "rms" that makes no sense. In your theory, as soon as your current draw hits 480 watts peak, the fuses will blow. That's not the same as 480 watts RMS.
And don't be so snippy.
--Dan.
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#241891 - 19/11/2004 21:07
Re: Deciphering Amp specs
[Re: tfabris]
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new poster
Registered: 23/05/2004
Posts: 15
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Quote:
Right, and I'm saying that the amp's maximum output is probably a lot less than the fuse rating. Stated another way, the fuse is most likely rated for a much higher amount of current than the amp can draw. That's on purpose, so that the fuse doesn't blow accidentally.
I'm just saying that, at best, looking at a fuse is a highly inaccurate way to determine the capabilities of the device that the fuse protects.
Right, look at a few amps rms ratings by different manufacturers, and using the rule i said work out the rms rating by the rule, compare them, and i think you would be surprised by the out come, i know this as this is something i did a few years ago when i first started selling ice.
And no its not as inaccurate as you would think because of the electrical systems in cars, the voltage is pretty much constant with little variation. Because of this the fuses are resonably accurate, and also manufacturers use as small as fuses as they think they can get away with because saving 1 cent on a fuse for each amp when they make ten of thousands of amps each year is a lot of money.
Lets remember what i said this rule is for: a quick simple way of being able to tell what approximate power an amp is.
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#241892 - 19/11/2004 21:33
Re: Deciphering Amp specs
[Re: djc]
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new poster
Registered: 23/05/2004
Posts: 15
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Quote:
You wrote it once, and quoted it again. It's the "rms" that makes no sense. In your theory, as soon as your current draw hits 480 watts peak, the fuses will blow. That's not the same as 480 watts RMS.
Correct me if i am wrong but you are saying that a 40 amp fuse with a 12 volt current must be able to give a higher output then 480 watts?
If thats you statement then you need to do a bit more learning before you get involved, no offense meant.
If not then you must be saying that what you think i am saying is that a 40amp fuse will only give 480watts, in which you have got the wrong end of the stick, my example was based on a 40 amp fuse and 12 volt power, which means a maximum output possible of 480 watts, the way to increase the wattage with the same ampage fuse is obviously to increase the voltage which i was using as a constant rather then as a variable.
In the "theory" i always use fuse ampage multiplied by 12 volts as the output to the theory is usually a very similar figure to the manufacturers rms rating at 14.4volts. This helps the theory to provide resonably reliable figures as the difference in voltage helps with the fuse overhead allowance (wiggle factor as previously called).
Quote:
And don't be so snippy.
--Dan.
I get "snippy" because the internet seems to be full of people who hear a interesting theory and instantly say that its BS, when they cant be bothered to actually spend the time to try out the theory, and lets face it they have the ability to find out wether or not it true using nothing but their mouse, fore finger and google.
I say to all of you, try the theory, if you believe it to be incorrect please PM me with your research that disagrees with it and i will read it, if i find that the theory works less then i think is reasonably useable i will be prepared to eat my own words and appoligise to all of you, but if you provide the disagreeable research be prepared to also have me provide examples of the theory working to you, and if we both agree that my research out weighs yours then i will also expect a post under this topic that says the theory works
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#241893 - 19/11/2004 21:53
Re: Deciphering Amp specs
[Re: scollinguk]
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carpal tunnel
Registered: 20/12/1999
Posts: 31597
Loc: Seattle, WA
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I disagreed with it because it just sounded wrong. You're right, I didn't research it and have no evidence to disprove what you said.
It's just that, to me, it sounded like the equivalent of choosing the best-tasting brand of peanut butter based on how difficult it is to open the lid.
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#241894 - 20/11/2004 14:59
Re: Deciphering Amp specs
[Re: scollinguk]
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carpal tunnel
Registered: 25/12/2000
Posts: 16706
Loc: Raleigh, NC US
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RMS is an average. It is possible for instantaneous power values to be greater than the RMS rating. In fact, they have to be unless you're sending a constant non-varying signal, which would, at least, be very uninteresting to listen to, amplified or unamplified. If the fuses are set at the amp's RMS value (divided by voltage, obviously), then normal usage could easily blow the fuses as the waveforms approach their peaks.
_________________________
Bitt Faulk
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#241895 - 20/11/2004 15:09
Re: Deciphering Amp specs
[Re: scollinguk]
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carpal tunnel
Registered: 21/05/1999
Posts: 5335
Loc: Cambridge UK
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Quote:
Also fuses are not only made for preventing fire if the power cables earth, i am not going to explain all the reasons for fuses as there are so many, but all i can say is that by that statement you are showing you naivety.
Maybe you should stop a moment, consider that someone with 22,500 posts to this board over the past several years is most likely not technically naive, and consider adopting a less aggressive tone. This is our community - kindly don't turn up out of nowhere and crap all over it.
Having worked in the CE industry for some years I'd suggest that determining an amplifiers performance from its fuse rating is voodoo at best. The fuse rating is meaningless unless you know:
1. The amplifier efficiency
2. Internal capacitance
3. Headroom allowed by the designers
Since you almost certainly do not know (1) or (2), and since (3) is always a rule of thumb which is then rounded up to the closest value available off the shelf, the outlook is bleak. The correct way to determine RMS and peak output capability is to refer to the manufacturers documentation, or to measure it at the output terminals under load.
You might also want to look into the meaning of the term "rms" if you're going to use it in pseudo scientific explainations.
Rob
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#241896 - 20/11/2004 17:09
Re: Deciphering Amp specs
[Re: rob]
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new poster
Registered: 23/05/2004
Posts: 15
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wfault: i completely agree, no-where have i disagreed with this
rob: once again, i feel people are being a bit pedantic about this, and yes i also know about what you are saying, and once again, you are disagreeing without testing. Also just because i have not posted much on THIS site doesnt mean that i dont know anything.
All: i think what i put in my previous post pretty much finilised the conversation, and i dont know why people are still posting about wether they agree or not with the theory on a "i just disagree, and cannot be bothered to actually see if it works or not" basis.
Also if someone posts something interesting on actual specific data that disproves my theory i will respond, but for people who are just going to quote standard electrical theory, which i already know, i wont bother.
PS RMS is an acronym for "root mean squared", where the exact output of the amplifier is recorded across a range of inputed signals and then there square root is applied to the results, then the mean average is taken and that mean average is then squared. This answer is then put in the bin and the marketing guys come up with a number they think is appropriate for the price they want to charge for the amp. (except genesis, who actually give their amps a birth certificate, with the exact output of that the actual amp you buy recorded on it.)
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#241897 - 20/11/2004 18:22
Re: Deciphering Amp specs
[Re: scollinguk]
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new poster
Registered: 07/10/2004
Posts: 4
Loc: The LBC
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Quote:
inputed
Fo' shizzle.
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#241898 - 20/11/2004 18:33
Re: Deciphering Amp specs
[Re: scollinguk]
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old hand
Registered: 15/07/2002
Posts: 828
Loc: Texas, USA
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You're correct. I have nothing else to add on amp ratings (after all I posted this topic to begin with).
But I can add something that you seem to side step with each post. You are being rude. You originally responded and I thanked you. This is the polite thing to do.
When tfabris contradicted you, you made it a personal attack. On this bbs, personal attacks are considered rude. Perhaps, you don't know this being new.
Given your background, it would be nice to have you around on the bbs but not if you're going to attack everyone who disagrees with you.
If you wish to carry this side discussion to PM, feel free.
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#241899 - 20/11/2004 18:47
Re: Deciphering Amp specs
[Re: rob]
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carpal tunnel
Registered: 20/12/1999
Posts: 31597
Loc: Seattle, WA
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Quote:
consider adopting a less aggressive tone
In his defense, I did cop a pretty serious attitude with my first response. So I deserved to get one in reply.
He's also got a point in that... if his real-world experience shows that the fuse rating is a good indicator, then it's possible that he's found a good quick "approximation" way of looking at it. Since I don't have a big list of all the amplifiers' fuse ratings compared to their actual RMS output values, I actually don't have any way of knowing if what he's saying is true.
I'm still not convinced, but I'll concede that what he's saying is possible.
Still sounds goofy to me though, like determining a car's top speed by looking at the highest number printed on the speedometer. 
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#241900 - 21/11/2004 03:05
Re: Deciphering Amp specs
[Re: scollinguk]
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Carpal Tunnel
Registered: 08/02/2002
Posts: 3411
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Quote:
...Also just because i have not posted much on THIS site doesnt mean that i dont know anything.
Yeah, but what little you have posted doesn't prove that you know anything either.
Quote:
All: i think what i put in my previous post pretty much finilised the conversation,
LOL. I haven't even started in the conversation yet and you're telling me I'm done? Who do you think you are?
Quote:
and i dont know why people are still posting about wether they agree or not with the theory on a "i just disagree, and cannot be bothered to actually see if it works or not" basis.
Because your theory is _CRAP_.
The only thing that you can tell about an amp from the fuse rating is how much current will flow before the fuse blows. And yes, occassionally this can be useful. For instance, when you see that a wonderfully spec'd chinese amp claiming 1000W output only has a 20A fuse, you know that the most use that you're going to get from the specification sheet is if you use it to wipe your arse. But that still doesn't tell you anything about the amp itself. You don't know what (if any) margin has been allocated before the fuse blows.
Quote:
And no its not as inaccurate as you would think because of the electrical systems in cars, the voltage is pretty much constant with little variation. Because of this the fuses are resonably accurate, and also manufacturers use as small as fuses as they think they can get away with because saving 1 cent on a fuse for each amp when they make ten of thousands of amps each year is a lot of money.
No, the voltage at the battery is anything but 'pretty much constant with little variation'. A car's electrical system is inherently very dirty. That is why alternator whine and ground loop noise are such big issues. But moving on from this consider the following two facts;
1.) Car audio manufacturers are well aware that people look at fuse ratings to debunk over-rated specifications and are not above abusing this, especially considering;
2.) It doesn't matter if I want 1A, 2A, 3A, 5A, 7.5A, 10A, 15A, 20A, 25A, 30A or 40A fuses. They all cost $0.195 in 10k quantities.
A better indicator is weight. You cannot build a powerful car amplifier without a decent PSU. Decent PSUs need decent heatsinks or they rapidly become dead PSUs. Decent heatsinks aren't light. Furthermore, a class AB design amp (which most are) requires heatsinking because it is inherently inefficient. The more powerful the amp, the bigger and heavier the heatsink required.
Even this is flawed though - some manufacturers make amps that you could fry your breakfast on, whilst other manufacturers' amps barely get warm. And a class D amplifier doesn't play by the same efficiency rules either. (You won't see a pure class B amp, and you're very unlikely to be using a class A amp).
_________________________
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#241901 - 21/11/2004 21:26
Re: Deciphering Amp specs
[Re: genixia]
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new poster
Registered: 23/05/2004
Posts: 15
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tfabris: i commend you on your turn around and very much argee with your "car top speed by looking at its speedo" comment as it does seem ike this to someone who hasnt tested the theory. All i would finish saying is if you think the theory would be useful to you, try it, go on a few manufacturers websites and look at the fuse vs rms ratings, if your never going to use it dont.
Mach: Seriously thank you for inviting me to hang around, if nothing else i have some interesting points of view, lol.
Quote:
Quote:
...Also just because i have not posted much on THIS site doesnt mean that i dont know anything.
Yeah, but what little you have posted doesn't prove that you know anything either.
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All: i think what i put in my previous post pretty much finilised the conversation,
LOL. I haven't even started in the conversation yet and you're telling me I'm done? Who do you think you are?
Quote:
and i dont know why people are still posting about wether they agree or not with the theory on a "i just disagree, and cannot be bothered to actually see if it works or not" basis.
Because your theory is _CRAP_.
The only thing that you can tell about an amp from the fuse rating is how much current will flow before the fuse blows. And yes, occassionally this can be useful. For instance, when you see that a wonderfully spec'd chinese amp claiming 1000W output only has a 20A fuse, you know that the most use that you're going to get from the specification sheet is if you use it to wipe your arse. But that still doesn't tell you anything about the amp itself. You don't know what (if any) margin has been allocated before the fuse blows.
Quote:
And no its not as inaccurate as you would think because of the electrical systems in cars, the voltage is pretty much constant with little variation. Because of this the fuses are resonably accurate, and also manufacturers use as small as fuses as they think they can get away with because saving 1 cent on a fuse for each amp when they make ten of thousands of amps each year is a lot of money.
No, the voltage at the battery is anything but 'pretty much constant with little variation'. A car's electrical system is inherently very dirty. That is why alternator whine and ground loop noise are such big issues. But moving on from this consider the following two facts;
1.) Car audio manufacturers are well aware that people look at fuse ratings to debunk over-rated specifications and are not above abusing this, especially considering;
2.) It doesn't matter if I want 1A, 2A, 3A, 5A, 7.5A, 10A, 15A, 20A, 25A, 30A or 40A fuses. They all cost $0.195 in 10k quantities.
A better indicator is weight. You cannot build a powerful car amplifier without a decent PSU. Decent PSUs need decent heatsinks or they rapidly become dead PSUs. Decent heatsinks aren't light. Furthermore, a class AB design amp (which most are) requires heatsinking because it is inherently inefficient. The more powerful the amp, the bigger and heavier the heatsink required.
Even this is flawed though - some manufacturers make amps that you could fry your breakfast on, whilst other manufacturers' amps barely get warm. And a class D amplifier doesn't play by the same efficiency rules either. (You won't see a pure class B amp, and you're very unlikely to be using a class A amp).
Grow up, get a wider view, and read my last two posts, i wont say it again.
Also weight? Firstly i will say that although i havent researched this i cannot say it isnt possible but i personally think it isnt probable. To me its like saying that a heavier car must have a bigger engine and so be quicker then lighter cars.
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#241902 - 22/11/2004 05:54
Re: Deciphering Amp specs
[Re: scollinguk]
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Carpal Tunnel
Registered: 08/02/2002
Posts: 3411
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Quote:
Grow up, get a wider view, and read my last two posts, i wont say it again.
Yawn. Someone else on the internet thinking that telling someone to grow up will somehow magically make their argument more persuasive. Sorry but that doesn't fly on this board. And nor does the offensively patronising tone.
IMNSHO, people that start a post telling others to grow up have usually already lost the argument.
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I say to all of you, try the theory, if you believe it to be incorrect please PM me with your research that disagrees with it and i will read it, if i find that the theory works less then i think is reasonably useable i will be prepared to eat my own words and appoligise to all of you, but if you provide the disagreeable research be prepared to also have me provide examples of the theory working to you, and if we both agree that my research out weighs yours then i will also expect a post under this topic that says the theory works
And you're telling me to grow up? You're presenting a theory with no data, and then expecting us to play by your rules in disproving it? And what happens if you don't agree with our research? Sorry, but around here if we've got something to say we generally say it out loud and let our opinions be judged by our peers. You see, if someone else disagrees with what I write here they are quite able to read it and say so here, without requiring the 'benefit' of you having decided its merits for them. It's called open peer review.
You got hard data from your research that supports your theory? Post it here if you're so sure. And since you seem to be rather cocky, I'm sure that you are sure.
Just remember that it only takes one negative to break a theory.
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Also weight? Firstly i will say that although i havent researched this i cannot say it isnt possible but i personally think it isnt probable. To me its like saying that a heavier car must have a bigger engine and so be quicker then lighter cars.
<sigh>
1.) You're ignoring the fact that most electronic components are extremely light compared to heatsinks.
2.) Weight has little bearing on top speed. Many cars now have electronic speed limiters that limit their top speed to that considered 'safe' by the engineers based upon a myriad of engineering considerations, tire ratings and supsension stability being two major considerations. Even removing that limiter, top speed is governed more by aerodynamic considerations than by weight.
3) Leaving cross-class and cross-manufacturer comparisons aside, you'll often find that a manufacturers fastest car is also their heaviest. The VW Phaeton W12 weighs 5100lb and would have a non-limited top speed of 178mph. The Golf R32 weighs around 2800 lb (from memory) and would max out at 155mph.
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Mk2a 60GB Blue. Serial 030102962
sig.mp3: File Format not Valid.
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#241903 - 22/11/2004 22:12
Re: Deciphering Amp specs
[Re: scollinguk]
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carpal tunnel
Registered: 25/06/1999
Posts: 2993
Loc: Wareham, Dorset, UK
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Quote:
40 amp fuse with a 12 volt current
The amp is the unit of current, not the volt. Volt is the unit of potential.
Quote:
40 amp fuse and 12 volt power
The unit of power is the Watt, not the volt.
Can you make up your mind on which quantity you are using the volt to define.
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In the "theory" i always use fuse ampage multiplied by 12 volts as the output to the theory is usually a very similar figure to the manufacturers rms rating at 14.4volts.
You are quoting (badly) the definition of instantaneous power, P = VI. A fuse will not blow at a given instantaneous power rating, otherwise the fuses of every electrical device on this planet would blow when they briefly attempt to consume more current than the fuse is rated at - for example, when you turn the volume up too high. However, the instantaneous power developed by any device does not depend upon it's fuse rating down (or indeed, up) stream. Fuses only indicate a desire to prevent say, a fire, in the event a device continues to consume power in a short-circuit condition which is likely to melt or burn it's casings or insulation.
A conventional lead-acid battery in good condition will have a 14.4V potential across 6 cells. 12 Volts is a notional "standard" battery voltage used by manufacturers based on a 2V per cell Pb-Acid cell electro potential.
These figures have nothing, other than co-incidence, to do with the calculation of RMS or Peak/absolute power figures. By the way, the square root of 2 is 1.414.
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the internet seems to be full of people who hear a interesting theory and instantly say that its BS, when they cant be bothered to actually spend the time to try out the theory, and lets face it they have the ability to find out wether or not it true using nothing but their mouse, fore finger and google.
This BBS seems to be full of qualified electronics engineers who know the theory already and do not need to use Google to come up with the design for the empeg players that this BBS supports.
_________________________
One of the few remaining Mk1 owners...  #00015
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#241904 - 22/11/2004 23:22
Re: Deciphering Amp specs
[Re: Mach]
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carpal tunnel
Registered: 12/11/2001
Posts: 7738
Loc: Toronto, CANADA
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Sorry, I should have weighed in on this thread earlier to avoid the long discourse. Let me end it simply: Phoenix Gold is crap. The rest of the thread is therefore irrelevant.  Bruno
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#241905 - 22/11/2004 23:54
Re: Deciphering Amp specs
[Re: scollinguk]
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carpal tunnel
Registered: 08/07/1999
Posts: 5549
Loc: Ajijic, Mexico
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i said the MAXIMUM output of the amp would be the total fuse rating multiplied by about 12 volts,
That's great!
That means I can take my 400 watt amp (which is equipped with a 40 watt fuse) and put a 100 watt fuse in it -- and I'll have a 1,000 watt amp!
Why didn't I think of that before...
tanstaafl.
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"There Ain't No Such Thing As A Free Lunch"
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#241907 - 23/11/2004 01:39
Re: Deciphering Amp specs
[Re: Mach]
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old hand
Registered: 14/02/2002
Posts: 804
Loc: Salt Lake City, UT
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I had a Phoenix Gold amp once (different model). The amp was rated at a higher RMS wattage than my rear speakers wanted, and all it did was overheat and shut off. And it had the whole trunk to itself! Maybe I should have some how rigged it up to my radiator and cooled it?
_________________________
-Michael
#040103696 on a shelf
Mk2a - 90 GB - Red - Illuminated buttons
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#241909 - 23/11/2004 13:15
Re: Deciphering Amp specs
[Re: Mach]
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carpal tunnel
Registered: 12/11/2001
Posts: 7738
Loc: Toronto, CANADA
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Na, I was just kidding. I don't have any personal bad experiences with PG amps. Not a fan of their spec practises nor their past marketing, but that's not related to how well it will perform for you.
If you're still unsure about the purchase, and don't want to test it yourself, definitely do some searches on the model in questions and then on similar models using google. Just be prepared for a lot of dork content.
Bruno
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A little closer to the info that I need. Please can you explain why? I have ordered this amp, but it's back ordered. I can still cancel the order so further details would be appreciated.
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