Advice?

[fmedina]

you guys are looking at the fuse ratings wrong. something i read on fusing.

just for future references, a good spec to look at is the fuse rating.

40a x 5

40 amps * 5 = 200 amps

200 * 14.4 = 2880

2880 * .8 (typical class D efficiency) = 2304

hmm your close.. try this..

I measure 12.8V, take 65% eff and my amp have two 30 amp fuse:

30A * 2 = 60A

60A + 1/3 = 80A (current point to blast fuse)(sinwave input-----squarewave output)

Now we need to calculate the RMS output value ...we will use 60A value

60A * 12.8V = 768VA

768VA * 0.65 = 499 ...say 500Watt RMS output

it is a simple maths formula which is average power = work done (unit of work is the the Joule) divided by time taken (unit of time is the second)

the unit of power = Joule/second (J/s)

Si unit of power is watt (w) = 1 J/s

so what we are looking for her is work done = force x distance to give us the Joule.

then we can work out how many watts it putts out which is power = work done/ second will give you how many watts anything is putting out

Hmm. English? Lol my brain just pooped out.

[autos]

you guys are looking at the fuse ratings wrong. something i read on fusing.

just for future references, a good spec to look at is the fuse rating.

40a x 5

40 amps * 5 = 200 amps

200 * 14.4 = 2880

2880 * .8 (typical class D efficiency) = 2304

hmm your close.. try this..

I measure 12.8V, take 65% eff and my amp have two 30 amp fuse:

30A * 2 = 60A

60A + 1/3 = 80A (current point to blast fuse)(sinwave input-----squarewave output)

Now we need to calculate the RMS output value ...we will use 60A value

60A * 12.8V = 768VA

768VA * 0.65 = 499 ...say 500Watt RMS output

it is a simple maths formula which is average power = work done (unit of work is the the Joule) divided by time taken (unit of time is the second)

the unit of power = Joule/second (J/s)

Si unit of power is watt (w) = 1 J/s

so what we are looking for her is work done = force x distance to give us the Joule.

then we can work out how many watts it putts out which is power = work done/ second will give you how many watts anything is putting out

Hmm. English? Lol my brain just pooped out.

Same

Edited July 2, 2011 by autos

[fmedina]

haha i love learning new shit about car audio makes me feel smarter

[kam311]

I emailed crescendo....but I also found this http://www.sonicelectronix.com/item_22707_Hifonics-HFi1500D.html

I've never heard anything good about the hifonics hifi series, I've heard they don't quite do rated and they don't doing good, most people will reccomend that you stay with brz and better. Plus that amp isn't going to get you 1000rms at 2ohm. I'd say go with crescendo man, it's the best deal by far. Go look at it's guts compared to a sundown, exactly the same, they even use the same board design. I'm not saying it's as good as or better than sundown, but what I am saying is it's going to he the best amp for the price by far

[irpirate]

you guys are looking at the fuse ratings wrong. something i read on fusing.

just for future references, a good spec to look at is the fuse rating.

40a x 5

40 amps * 5 = 200 amps

200 * 14.4 = 2880

2880 * .8 (typical class D efficiency) = 2304

hmm your close.. try this..

I measure 12.8V, take 65% eff and my amp have two 30 amp fuse:

30A * 2 = 60A

60A + 1/3 = 80A (current point to blast fuse)(sinwave input-----squarewave output)

Now we need to calculate the RMS output value ...we will use 60A value

60A * 12.8V = 768VA

768VA * 0.65 = 499 ...say 500Watt RMS output

so what you're saying is that at 80 amp draw the fuses will blow and that your figuring the rms output at 12.8 volts 65% efficiency?

[autos]

well crescendo has not emailed me back and I am an impatient person so I got this http://www.sonicelectronix.com/item_23547_Hifonics-Brutus-BRZ1700.1D.html

[homiewes]

you guys are looking at the fuse ratings wrong. something i read on fusing.

just for future references, a good spec to look at is the fuse rating.

40a x 5

40 amps * 5 = 200 amps

200 * 14.4 = 2880

2880 * .8 (typical class D efficiency) = 2304

hmm your close.. try this..

I measure 12.8V, take 65% eff and my amp have two 30 amp fuse:

30A * 2 = 60A

60A + 1/3 = 80A (current point to blast fuse)(sinwave input-----squarewave output)

Now we need to calculate the RMS output value ...we will use 60A value

60A * 12.8V = 768VA

768VA * 0.65 = 499 ...say 500Watt RMS output

so what you're saying is that at 80 amp draw the fuses will blow and that your figuring the rms output at 12.8 volts 65% efficiency?

correct

[kam311]

Patience is a virtue... Crescendo only has like 2 or 3 people working in there. The best way is to call them, but it's also the 4th of July man... But it's okay, just don't expect 1000wrms at 2ohms

[Dubpower]

you guys are looking at the fuse ratings wrong. something i read on fusing.

just for future references, a good spec to look at is the fuse rating.

40a x 5

40 amps * 5 = 200 amps

200 * 14.4 = 2880

2880 * .8 (typical class D efficiency) = 2304

hmm your close.. try this..

I measure 12.8V, take 65% eff and my amp have two 30 amp fuse:

30A * 2 = 60A

60A + 1/3 = 80A (current point to blast fuse)(sinwave input-----squarewave output)

Now we need to calculate the RMS output value ...we will use 60A value

60A * 12.8V = 768VA

768VA * 0.65 = 499 ...say 500Watt RMS output

it is a simple maths formula which is average power = work done (unit of work is the the Joule) divided by time taken (unit of time is the second)

the unit of power = Joule/second (J/s)

Si unit of power is watt (w) = 1 J/s

so what we are looking for her is work done = force x distance to give us the Joule.

then we can work out how many watts it putts out which is power = work done/ second will give you how many watts anything is putting out

Hmm. English? Lol my brain just pooped out.

Same

the time is how long the current takes to reach the amp, then how many watts the amp draws from the alternator to the amp is the first part which you find out how many joules it putts out

then when you got the juole, then it is divided by how many seconds it takes to reach the speaker or speaker

[skittlesRgood]

you guys are looking at the fuse ratings wrong. something i read on fusing.

just for future references, a good spec to look at is the fuse rating.

40a x 5

40 amps * 5 = 200 amps

200 * 14.4 = 2880

2880 * .8 (typical class D efficiency) = 2304

except %80 efficiency is measured at 4ohm. drop resistance and the efficiency drops too. i usually just multiply the amperage by 10. that seems to come pretty close after efficiency and a little voltage drop.