nobody likes rockford fosgate??

[audioholic 5,000+ posts]

There is no doubt it relies on the transient nature of music to stay charged.

 

[snoopdan 5,000+ posts]

There is no doubt it relies on the transient nature of music to stay charged.

no, there is just no doubt that your statement IS correct //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[romans535 10+ year member]

I'm starting to wonder if you guys even know the amp you're so proud of....
First, look at the RF literature. The Hybrid Technology is predominantly described as a current-averaging system. In case the diction doesn't make it clear, the T15K draws less peak current by drawing more current during low output, which is then stored in the capacitors for use during high output.

As already noted, the T15K does not have efficiency greater than 100%. Power (energy over time) output cannot exceed power input. During low demand, the amplifier actually has a negative efficiency (relative to output). The energy stored in the capacitors during this period means you get extremely high efficiency during high demand periods (relative to output). However, this efficiency cannot be sustained...and should not be specified with the continuous ratings. What you are looking at is 15kW of output for short bursts, not continuous tones. How it got CEA-2006 rated is beyond me...

I doubt math will help others, because they're obviously already ignoring it, but we'll try anyway...

If the battery only supplies as much as 350 amps at 14.4 V, the power from the battery is 5040 watts. If we assume AB efficiency of 80% (generous), you're looking at a little over 4000 watts output provided by from the battery. So where's the rest of that energy coming from.....?

We know the amp uses a large bank of capacitors. RF has mentioned in the past that it offers 225,000 joules. The roughly 11,000 watts remaining (to achieve the published 15,000 watt rating), all of which must go through a class AB output stage. Again, assuming 80% efficiency, you're looking at 14,000 watts input to achieve the remaining 11,000 watts output.

So, coming back to the 225,000 joules. A joule is a watt-second. Taking 225,000 joules and dividing it by 14,000 watts, you're looking at ~16 seconds of continuous output at that level.

And guess what happens once the capacitor bank is drained....you need to start filling it back up. To charge the 225,000 joules worth of capacitors back up, you know again that we can't supply anymore than 4000 watts (per RF's own literature, ie. the 350 max amps of current draw...see math above). Take 225,000 joules (or watt-second) and divide by 4000 watts....it will take approximately 56 seconds of continuous 350 amp current draw just to charge the capacitor bank again!

In reality, what you have is an amplifier that can do 4 kW continuous, and supply 15,000 kW peak for short bursts. Oddly enough, most people normally object to companies that rate products like RF has here....

This is good, I do have a question though. You said "if the battery only supplies 350 amps" is that the most current available for this type of amp set up. And would the resistance make a difference in all these calculations.

voltage= current(amps) x resistance(ohms)

power(watts)= current x voltage

is this right

 

[sonic purity 10+ year member]

There is no doubt it relies on the transient nature of music to stay charged.

I dont think anyone would argue that.

It says so right in the specs on the amp

 

[mokedaddy 5,000+ posts]

I dont think anyone would argue that.
It says so right in the specs on the amp

Then its not continuous. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif No amp is.

 

[sonic purity 10+ year member]

rms would be the correct acroynm

Thats how continous power is rated with amplifiers

 

[sonic purity 10+ year member]

cause music is not continous, or is it dc

 

[mokedaddy 5,000+ posts]

rms would be the correct acroynm
Thats how continous power is rated with amplifiers

Kind of. There is one fundamental difference. This amp will not play a sine wave whereas a normal amplifier will. Thus IMO where it should be differentiated. I have no problem with the 15k rating for music, but it is still misleading, imo.

 

[sonic purity 10+ year member]

yes, the amp will play a sine wave, what do you think music is? It almost double its rated power at peaks, where is the confusion there?

 

[audioholic 5,000+ posts]

I dont think anyone would argue that.
It says so right in the specs on the amp

So.... where in lies the argument? //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[audioholic 5,000+ posts]

yes, the amp will play a sine wave, what do you think music is? It almost double its rated power at peaks, where is the confusion there?

My confusion at this point stems from why you are mentioning peak power. His point was this type of amp could not sustain full output indefinitely, where as a 'normal' amp could. It is a true statement, the only questionat this point is how long, and who really cares. Your insertion of peak output in your response is what is confusing. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[DDSC 10+ year member]

all NEW technology costs money.......how long ago did a 50" plasma cost 10 grand? not THAT long ago //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif Especially when there was only 18 plasmas in the world, how much do you think one cost then?

truf, was just reading in the paper the other day where they had a 28000 dollar fifth of Remy Martin and there was only 75 bottles of it in the world, 1500 for ONE SHOT. Of course the shit had been aged for 100 years but still

 

[DDSC 10+ year member]

My confusion at this point stems from why you are mentioning peak power. His point was this type of amp could not sustain full output indefinitely, where as a 'normal' amp could. It is a true statement, the only questionat this point is how long, and who really cares. Your insertion of peak output in your response is what is confusing. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

I would care, I love long bump sessions of course ive never had a 15000 watt rms bump session so I dont know how long I would like that but you get the point

 

[sonic purity 10+ year member]

My confusion at this point stems from why you are mentioning peak power. His point was this type of amp could not sustain full output indefinitely, where as a 'normal' amp could. It is a true statement, the only questionat this point is how long, and who really cares. Your insertion of peak output in your response is what is confusing. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Your confusion is that you dont seem to understand what rms means. CEA would not have rated it like they did if it couldnt sustain that power over a long period of time.

Peak is the icing on the cake

 

[sonic purity 10+ year member]

I guess if all the power number were the same as a regular amp, they wouldnt have been able to patent it.