Approx RMS

[wilson_gau 10+ year member]

My amp (guts) look like this. What do you think the approx RMS (at given OHM: 8, 4, 2, and 1 ohm - since this is NOT 0.5 ohm stable)?

The spec is:

Model : LM Audio - LM 3200.1D (Class D) ▪ 1 Channel Class D Power Amplifier ▪ 1 x 3000 Watt (1 Ohm) ▪ 1 x 700 Watt RMS (4 ohm) ▪ 1 x 1300 Watt RMS (2 ohm) ▪ THD at 1 Watt, 4 Ohms : 0.30% ▪ THD at 1 Watt, 4 Ohms : 0.50% ▪ Signal - to - Noise ratio : 100dB ▪ Frequency Response, at 1 Watt, 4 Ohm : 15Hz to 150Hz (+/- 3dB) ▪ Frequency Response, at rate power, 4 Ohms : 20Hz to 250Hz (+/- 3dB) ▪ Damping factor at 20Hz, 4 Ohm : 400 ▪ Crossover Low Pass : 50Hz - 150Hz 24dB/Octave ▪ Crossover Subsonic (High Pass) : 15Hz - 40Hz, 24dB/Octave ▪ Bass Boost : 0 + 18dB ▪ Phase Control : 0 to 180 Degree ▪ Input Sensitivity : 100mV to 2V ▪ Input Impedance : 10K Ohm ▪ Line Output Impedance : 100 Ohm ▪ Peak Current Consumption, at rated power into 1 Ohm : 160 Amperes ▪ Dimensions : 20'L x 7'W x 2,36'H ▪ Fuse Rating : MFU 80A x 2

On the other end, could you explain if calculating the RMS for blade fuse (which is most common in amp) with this kind of fuse (tube fuse)? - ie. given the same efficiency for both amps, will an amp with 60A x 2 tube fuse has the same output with another amp with 30A x 3 blade type fuse?

Thanks for any input!

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[disturbed471985 5,000+ posts]

Clamp it and let us know.. No one can say what kinda power u are going to get from a certain amp.

 

[wilson_gau 10+ year member]

Sorry, not familiar with the clamp (or those testing method). I just need a ballpark of what the RMS you think based on the guts. I know the fuse is 80Ax2, but unsure if a tube fuse has the same rating as blade fuse..

 

[disturbed471985 5,000+ posts]

I am not up to date with tube amps so I cant help with that. But clamping is a method to see what power you are actually getting from a certain amp. Internals look nice though so I would expect some good power from it but how much IDK.. I would say any easy 2k@ 1ohm maybe alot more.

 

[The_Grimy_One 10+ year member]

Sorry, not familiar with the clamp (or those testing method). I just need a ballpark of what the RMS you think based on the guts. I know the fuse is 80Ax2, but unsure if a tube fuse has the same rating as blade fuse..

I do believe tube fuse amperage is equal to blade fuse... They are just different types of fuses... But regardless, no one can just guess the RMS of the amp :/

 

[>>SQL<< 10+ year member]

a ballpark est is an amps max RMS at its lowest stable ohms will be around 80% of its fusing.

This is just a rule of thumb

so on your amp if it is 1 ohm stable then at 1 ohm you should be around 1,600 watts max RMS

I got that by 13 (volts) x 160 (amps) x .8 (80% efficient) = 1,664

So I would say its rating of 1,300 watts @ 1 ohm is likely

Each doubling of OHMS drops RMS by half so...

1,300 watts @ 1 ohm

650 watts @ 2 ohm

325 watts @ 4 ohm

 

[>>SQL<< 10+ year member]

I am not up to date with tube amps so I cant help with that. But clamping is a method to see what power you are actually getting from a certain amp. Internals look nice though so I would expect some good power from it but how much IDK.. I would say any easy 2k@ 1ohm maybe alot more.

He did not say he had a tube amp, he has the glass tube style fuses.

Also how would an amp with 160 amps of fusing do an easy 2,000 watts?

It would have to be over 100% efficient, the only amps I know of like that are the BOSS amps (joking)

 

[disturbed471985 5,000+ posts]

If u will go back and look I never said what power it would do only a guess. I have seen saz-1500's 160amp fusing do well over 1900watts@1ohm clamped.. Soo yea thats real world..

 

[disturbed471985 5,000+ posts]

Just cause an amp is fused for 160amps does not mean it can not pull more then 160amps without blowing the fuse..

 

[>>SQL<< 10+ year member]

Just cause an amp is fused for 160amps does not mean it can not pull more then 160amps without blowing the fuse..

it all depends on how you want to measure things.

You are right, an amp CAN pull more amps than its fusing -- but only for very short bursts

I like to use how much power an amp can continually produce - like on a 50 hz test tone

So we are both right - it is possible that the amp the OP has can hit 2,000 watts

and I think it is also very likely that the OP's amp can continuously produce around 1,300 - 1,600 watts

Either way it is a beast of an amp and puts my little Audiopipe to shame.

 

[disturbed471985 5,000+ posts]

it all depends on how you want to measure things.You are right, an amp CAN pull more amps than its fusing -- but only for very short bursts

I like to use how much power an amp can continually produce - like on a 50 hz test tone

So we are both right - it is possible that the amp the OP has can hit 2,000 watts

and I think it is also very likely that the OP's amp can continuously produce around 1,300 - 1,600 watts

Either way it is a beast of an amp and puts my little Audiopipe to shame.

Good deal we were both on the same rd just looking at it different. Yea but ur AP was cheap for all we know the OP payed $900 for this amp so he might have got the rip hammer brought down on him.

 

[duanebro 10+ year member]

It looks sweet, it should be mounted so that you can see the guts.

 

[bubbagumper6 5,000+ posts]

Just cause an amp is fused for 160amps does not mean it can not pull more then 160amps without blowing the fuse..

He asked for the RMS output of the amp, what you're referring to is just peak draw and has no bearing on the situation whatsoever //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

 

[Canaan 10+ year member]

Model : LM Audio - LM 3200.1D

The company 'calls' the amp a 3200.1, this is likely peak power. Many companies that list 'peak' power usually translate into ~1/2 that RMS. Also, its fused at 160A w/ AGU fuses.

I would say ~1600wrms @ 1ohm is reasonable for this amp. Maybe slightly more.

 

[disturbed471985 5,000+ posts]

He asked for the RMS output of the amp, what you're referring to is just peak draw and has no bearing on the situation whatsoever //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

I beg to differ the draw of an amp does apply to what kinda power you will see from an amp.... So since u seem to be intune with the whole audio world what is the true rms of this amp?? Thats right u dnt know just like no one else does.