jbl 600.1

the jbl 600.1 amp, is that 600 rms @2 ohms, or max wattage?

Replies (8)

Swez on 04/1/2003 18:42:01
The 600.1 is rated @ 600 RMS output , 1 or 2 ohms ... 12.9 volts power supply. So, if you feed it 13.5 volts, and have a 1-2 ohm load, pushing close to 650 RMS. (AKA: 1300 watts PEAK) That's a bit more than output a Sony 1200 Watt amp.

xplicitblitzboi on 04/5/2003 23:17:58
lol, and i'll take JBL reliability over sony any day. its just like the 1200.1, it doesnt make much of a difference at 1 or 2 ohm, with 1 ohm, you just get 1400 watts instead of 1200, somewhere around there, it doesnt double as it does with other amps. i reccomend this amp highly, especially since it is a fairly nice amp for under 200 dollars, www.etronic.com sells for about $175. but if your thinking about upgrading your system, always think about a new alternator, as a real 1200 watt amp will be pulling around 86 amps :)

Swez on 04/6/2003 10:57:25
Actually, the 600.1 pulls ~57A of current at full output. The 1200.1 is double that... 114A. The good news, these are Class D amps with PWM (Pulse Width Modulated) power supplies. So, their duty cycle is short.

That means high power output, vs amps drawn to produce the output watts. (80%+ eff. ratings) As noted above, if your alt/battery can support that much current draw... all is well. Just make sure your subs can take that much power RMS. Peak power numbers (like Sony and other brands use) are deceptive. What you really need to know... is the RMS power of amp and drivers.

Hope that helps,

Swez

xplicitblitzboi on 04/6/2003 16:57:52
Most electrical systems will crank out around 13.8vdc with the engine running. So, 1,200 watts divided by 13.8 volts equals 86.95 amps. if you want to be modest with the 600 watts i guess you could divide by 12, but that would still leave u with 50 amps, double that would be about 100 amps.....

http://www.eatel.net/~amptech/elecdisc/charging.htm

i guess you do have some other things to factor in, but thats why i said 12 instead of 13.8 if you want to be closer.

Swez on 04/7/2003 13:16:07
True enough XP... many cars/trucks can do 13.4 - 13.8 volts constant and if the voltage input is higher, the current draw for rated power will be lower. Good catch!

This just means that JBL is very conservative in rating the amps they make. Some rate amp power output at 14.4 volts to boast higher power output numbers. In the real world, special power supply modifcations are needed to meet that steady 14.4 volts and these mods are not cheap.

Great site reference too. I use eatel often for research and digging into the deeper issues common in 12 volt systems and other audio related details.

Swez

schlsux on 04/18/2003 23:32:22
So when JBL rates their amps, they rate the max wattage @4ohms? Most rate their max @ 2 ohms. I just didn't think this thing really put out 600 RMS @2 ohms.

Swez on 04/19/2003 07:22:00
JBL rates their amps @ 12.9 volts input. The total RMS output is about the same for 1 or 2 ohm loads. In this case, 600 watts RMS @ 1 or 2 ohm loads. If you run it with a 4 ohms load, the output power will drop to ~300 watts RMS. That's only -3dB less SPL BTW.

Need to define RMS vs Peak power here:

RMS Watts = Root mean Squared is average output value of a given amp, to a specified load (similar to continous output power) RMS is the equal amount of energy produced by an equvilent DC power source. (Ie: 10 volts DC = 10 volts RMS of AC power)

Peak Watts = is approximately 2 x higher number than RMS figures as the spec takes a snapshot of the peak positive voltages pulses above "0 volts reference" line.

RMS is the most reliable method for determining an amps output capability or comparing many amps to each other. Basically, compare apples to apples, not apples to pumkins. Use the same nomenclature for a more accurate representation of the amps performance.

Some makers take it one step further and give Peak to Peak watts. This is really a bogus way of rating amps...

Example: a 200 watt RMS amp that is labled 800 P-P watts. If you see a tiny amp and a small fuse (25 amps) rated at ~200 watts RMS, you getting a honest rating. If same amp is rated @ 400 watts peak or 800 watts P-P, these guys are playing games with the numbers.

FYI: Look at the input voltage # used to rate amp power. If they rate power output RMS watts @ 12.5-13.5 volts, you're getting a pretty honest rating. However, if that same amp were rated at 14.4 volts input, the RMS output numbers will be somewhat higher. Thing is, most vehicles cannot sustain a 14.4 volt input to the amp. A special power supply can... but a typical car electrical system cannot.

Many amp makers try to beef up their output values buy using terms like "Dynamic Power" or 14.4 volts input voltages. In the real world of car audio, these are bogus claims to shamelessly decieve the unknowing buyer.

Does that make sense to you?

Swez

megahurts4 on 04/20/2003 20:10:56
Holy crap! The 600.1 is rated at 12.9 volts?! Crap! Mine's running at 14.4 volts, and at 2 ohms to a, yes *a*, Perfect 12.1d. I thought I was already overpowering it. But not at 669.8 watts rms. I thought it was just 600 rms going to a 350 rms sub.

It has no problems tho. Soo, I'm done freaking out.