efficiency

[denalilvr 0]

when someone says there amp is 80% efficient at 2600 watts what exactly does that mean electrical system wise?

[JimJ 11]

It means that out of all the power consumed by the amp, 20% of it is wasted as heat.

I don't exactly know what you mean by what you're asking, you size the electrical system according to the current draw - which is a direct result of the efficiency of the amp - and the voltage drop.

[denalilvr 0]

you answered the question for me..so basically 20% of the amps power is waisted due to heat and your only getting 80% of its power to your subs?

[ANeonRider 3]

No... it means that 20% of the current draw is wasted in heat. That means if you have an amplifier capable of 1000W, it needs 1200W worth of power to supply it.

P.S. About 95% of the power your amplifier supplies is wasted as heat.

[sick6ness 1]

"This is the ratio of of power input (from the battery) to power output (to the speakers). A 100 watt amplifier with an efficiency of 50% would take in 200 watts of power from the battery and output 100 watts of power to the speakers. The other 100 watts of power would be wasted as heat. The higher the efficiency of an amplifier the better. Most class A/B amplifiers are around 50-60% efficient and Class D around 80%. Amplifiers are generally less efficient at low power and more efficient at full power so this number varies in actual use."

[JimJ 11]

Well...given enough power to run it, I would say efficiency usually means squat, as there are extremely nice amplifiers that have horrendously low efficiency ratings

[shizzzon 461]

that's why high efficiency is a good thing, especially if we are talkin about goin over 2kw of power.

If you wanted to up to 10,000w of power, for example, but are trying to save money, High Current amps may be cheaper than the class d alternative.

So let's say you bought 5 2,400w HC amps for $299 per amp.

Well, let's say 5 2,500w class d amps were $500 per amp.

$1,500 vs $2,500.. you'd go with $1,500 to save money.

Let's say the HC amps are only 65% efficient whereas the Class d amps are 80% efficient.

Now, let's say either setup, you have 4 200a alts in there and 5 HC2400s in the rear.

5 HC2400s is good for 12,000w of power.

5 2,500w amps is 12,500w and 5 2,400w amps is 12,000w so we are right on so far.

Now, this is where things start to change-

Let's say that the fuse ratings for the 2,400w and 2,500w amp are the same at 250A.

250 x 5 = 1,250 \ 2 = 625A which is considered average draw for music.

So now we focus on efficiency at 625A of draw-

Class d amp=

80% efficient - to draw 625A @ 13.0v

13v x 625A = 8,125w of power draw.

@ 80% efficiency, it will output - 6,500w of power!

High Current amp=

65% efficient 0 to draw 625A @ 13.0v

13v x 625A = 8,125w of power draw.

@ 65% efficiency, it will output - 5,281w

So... how much more power is needed for the HC amps to output the same power as the class d amp?-

Another 1,219w

How many more amps?

It would need to PULL 769.2A to output 6,500w which equals a need to pull an ADDITIONAL 144.2A of current.

So, what do you need to do electrical system wise for that?

Kinetik's battery names are done like taking averages of amp draw by 50% of their max rating.

If you have 200A fuse, take half of that, 100A and that should be your battery's aH rating or summed aH rating.

5 HC2400s have an aH rating of 630A, this example was for 625, close huh

But because you tried to save money using HC amps due to low efficiency, now it looks like you have a 20,000w setup rather than a 12,000w setup!

Remember, the 6,500w output from class d amp is HALF of the maximum installed wattage potential, (going by fuse ratings).

So, if the HC's draw an additional 144.2A, you would need ANOTHER HC2400 AND about 1-2 more 200a alts equaling 5-6 alternators!

How much money did you save when you bought the amps? $1,000.

How much money must you drop into the vehicle now for getting the electrical supported?

$330 for the battery.

$550 for 2 more alts + custom brackets......again($100)

Another large ass amount of wire $80

Total so far- $1060

Plus you gotta remember- the lower the voltage goes from here, the more current it will draw over the class d amp anyway so power requirements might actually be more than this under heavier loads!

See the pain involved?

Adding extra battery, takes up room, weight, re run more wiring, gotta get another alt.... do u got room for another one, will one very large even fit?

Efficiency is a must.

Sometimes i wish my car was completely 48v. They were suppose to start doin that soon but havent heard anything about it in years.

The reason i wish is the higher the voltage, the smaller guage of wire you can use and the smaller the batts can be. Large this and extra battery that is all blamed on high current draw, nothing else.

[sick6ness 1]

Well put shizzzon!

But what would you say sounds better a class AB amplifier with 100x4 watts or a class D 100x4?

[ANeonRider 3]

Indistinguishable in a car, in a uber quiet enviroment like a treated room in a home, maybe.

Amplifier efficiency is only ever taken into account in car audio, and some still don't. Depends on your system goals.

Driver efficiency is just as important, if not more.

[ANeonRider 3]

P.S. WTF is a high current amp. Don't make things up. Ohms law hasn't changed. I quit reading after that.

[audio-neon 34]

Well put shizzzon!

But what would you say sounds better a class AB amplifier with 100x4 watts or a class D 100x4?

Honestly good quality solid state amps will have a negligible difference in SQ for the average consumer.

[shizzzon 461]

That's what they're called.

Maybe it's some companies way of warning people before buying it....

Warning- draws High current.... terrible efficiency... look at our other lines...... cheap ass <cough...cough> hehe

[///M5 2,833]

Well put shizzzon!

But what would you say sounds better a class AB amplifier with 100x4 watts or a class D 100x4?

Honestly good quality solid state amps will have a negligible difference in SQ for the average consumer.

Actually even for the above average consumer, in particular for in vehicle applications.

[denalilvr 0]

great info here guys thanx alot..

[Penguin4x4 1,761]

P.S. WTF is a high current amp. Don't make things up. Ohms law hasn't changed. I quit reading after that.

An amp with a 600A fuse rating?

[almond 0]

like the old orion xtr 2 channel class a/b amps that run 2400 watts rms at 60% or less efficiency at 1 ohm.

or the ma audio amps that are class a/b that are current hogs. those are high current amps.

they are class a/b high current (can drop under 4 ohms mono) yet arent class d amps (which well expect to be 1 ohm stable.)

[JimJ 11]

60% efficiency is pretty good compared to what I'm used to

[todd.brust 29]

60% efficiency is pretty good compared to what I'm used to

lol. I looked into building a Zen amplifer a while back and I was looking at below 10% efficiency!

What would be a guesstimate for tube amp efficiency? I never really though about it?

[JimJ 11]

60% efficiency is pretty good compared to what I'm used to

lol. I looked into building a Zen amplifer a while back and I was looking at below 10% efficiency!

What would be a guesstimate for tube amp efficiency? I never really though about it?

The theoretical maximum for a true Class A1 amp (tube or solid state for that matter) is 25%...I haven't put a clamp meter on the monoblocks yet but I'd be surprised if they were above 20%.

Push/pull amps are significantly more efficient. Something like a Dynaco ST70 actually runs pretty cool, while I wouldn't suggest touching the tubes in use the transformers don't get anywhere near as hot as in a SET, for example

Actually, some of the most efficient amps in the world are Class C amps that may use tubes, the problem is that without specifically tuned circuits they're prone to all sorts of distortion and nasty harmonics, and such can be only used for very narrow bandwidth applications...mostly RF transmission.

[denalilvr 0]

60% efficiency is pretty good compared to what I'm used to

lol. I looked into building a Zen amplifer a while back and I was looking at below 10% efficiency!

What would be a guesstimate for tube amp efficiency? I never really though about it?

The theoretical maximum for a true Class A1 amp (tube or solid state for that matter) is 25%...I haven't put a clamp meter on the monoblocks yet but I'd be surprised if they were above 20%.

Push/pull amps are significantly more efficient. Something like a Dynaco ST70 actually runs pretty cool, while I wouldn't suggest touching the tubes in use the transformers don't get anywhere near as hot as in a SET, for example

Actually, some of the most efficient amps in the world are Class C amps that may use tubes, the problem is that without specifically tuned circuits they're prone to all sorts of distortion and nasty harmonics, and such can be only used for very narrow bandwidth applications...mostly RF transmission.

jim, when i read your answers to peoples questions, i feel like your a god among men

[sick6ness 1]

lol denali you're a funny dude

[todd.brust 29]

60% efficiency is pretty good compared to what I'm used to

lol. I looked into building a Zen amplifer a while back and I was looking at below 10% efficiency!

What would be a guesstimate for tube amp efficiency? I never really though about it?

The theoretical maximum for a true Class A1 amp (tube or solid state for that matter) is 25%...I haven't put a clamp meter on the monoblocks yet but I'd be surprised if they were above 20%.

Push/pull amps are significantly more efficient. Something like a Dynaco ST70 actually runs pretty cool, while I wouldn't suggest touching the tubes in use the transformers don't get anywhere near as hot as in a SET, for example

Actually, some of the most efficient amps in the world are Class C amps that may use tubes, the problem is that without specifically tuned circuits they're prone to all sorts of distortion and nasty harmonics, and such can be only used for very narrow bandwidth applications...mostly RF transmission.

Lol class C. I have never worked with them, but I vaugely remember them. Dont they just use and inductor and capacitor and resonate at the FR?

Jim aren't you an RF guy? HAM/CB?

[JimJ 11]

Jim aren't you an RF guy? HAM/CB?

Yep

Dont they just use and inductor and capacitor and resonate at the FR?

Bingo. Geek-speak for it is a "tank circuit" and when tuned to the desired harmonic, it accepts that frequency and rejects others. Back in the '20s and '30s a bunch of people came up with different circuits to do the same thing (Hartley/Colpitts/Armstrong oscillators, etc, etc) but they're all just variations on the same LC circuit theme with different numbers of caps or inductors.

[ANeonRider 3]

Feel like I'm back in school here guys

[JimJ 11]

Feel like I'm back in school here guys

Hey, as long as I don't have to read Smith charts or do complex impedances I'm OK with it

The ins and outs of transmission line/balun theory is a monumental pain in the ass to me for some reason...