I was wondering how would 4 ethos 15s perform on a crescendo 5500 I'm really stuck inbetween 4 ethos 15s and two zv4 18s

Ethos hands down Wtf

That's what I want but I don't want to go much over 6000 watts do I need to only get 3 ethos or will 4 still perform well on a 5500 or do I need to get two 3500s

The 1,800 watt rating is not a thermal rating. It is the rms power needed to drive them to Xmax (32.5 mm) in a 3 cft box tuned to 32 hertz. As with any sub/box combination this will vary. However this is the median rating needed for the recommended enclosures.

If you were to use 5500 watts on 4 then you can expect the drivers to reach ~25mm one way.

So 4 x 25mm = 100mm

3 x 32.5mm = 97.5mm

This is IF you can get the full 5,500 watts with an odd ohm load with the three subs.

So four is the better option thanks hopefully I will order within the next few days and is it possible for you to help me with a box design when I order?

I would run 3 if you only run a 5,500 and only if you can get 5,500 watts on the odd ohm load. If you can't get the full 5,500 with an odd ohm load or if you run two 3,500 I'd definantly run 4.

No problem helping with the box design. Would not be worth it to build it for you as something that large would need to be freighted.

The 1,800 watt rating is not a thermal rating. It is the rms power needed to drive them to Xmax (32.5 mm) in a 3 cft box tuned to 32 hertz. As with any sub/box combination this will vary. However this is the median rating needed for the recommended enclosures.

If you were to use 5500 watts on 4 then you can expect the drivers to reach ~25mm one way.

So 4 x 25mm = 100mm

3 x 32.5mm = 97.5mm

This is IF you can get the full 5,500 watts with an odd ohm load with the three subs.

Quentin-

 

You should really start calling it "Recommended Power" and keep the term RMS out of the equation entirely, I know what you are trying to do, but it gets confusing when RMS power is a thermal rating for everyone else...

 

-Mike

"Rms:

Units are not usually given for this parameter, but it is in mechanical 'ohms'. Rms is a measurement of the losses, or damping, in a driver's suspension and moving system. It is the main factor in determining Qms. Rms is influenced by suspension topology, materials, and by the voice coil former (bobbin) material."

I see no mention of thermal rating.

"Rms: [N*s/m] The losses due to the suspension" -thielesmall.com

Your looking at the wrong RMS (Rms).

Speaker manufacturers use RMS (Root Mean Square) wattage (derived from RMS voltage) to give a continuous thermal power rating over a given set of parameters.  Some manufacturers don't correctly relate true RMS measurements into the continuous rating, but they are still implying a thermal limit, not an overall mechanical & thermal limit... 

Ohh, how many RMS are there Honda? How do I differentiate the two?

How do I find the RMS definition that you are referring to? Is there a link you can provide so I can do more research on the matter.

RMS = Root Mean Square.   It is an electrical mean or average.

 

**And before anyone jumps on me for saying RMS is correctly used to measure thermal capacity by all manufacturers, I am saying it is NOT always used correctly.  BUT, it is used in conjunction with some sort of thermal rating.**

So it's "suppose" to be used in conjunction with a thermal rating? The thermal rating of what exactly? I'm just trying to get an clear understanding when a driver has an Rms rating because Root Mean AND the T/s RMS definitions both do not mention anything in regards to thermal?

Pay close attention to the way they are spelled.  You are talking about Rms, I am talking about RMS (also abbreviated rms).  But again, manufacturers do not always correlate RMS (rms) to continuous power correctly, but they still intend a relation to thermal capacity (how much power the driver can dissipate before some kind of thermal failure).

 

Quentin is trying to help people by rating his drivers with an RMS that approximates the total power needed to get the drivers to stroke in a particular alignment.  His rating makes more sense to 99% of the users out there.  It is just different than what is (has) been done for years.  All I was pointing out is that if he called it something different, it would make more sense and cut down on confusion...  Adire Audio used to post power charts for particular alignments, it let you know how much power you needed.  They made a clear distinction between this rating and the RMS thermal rating.

Well my lawyer told me I wouldnt get my settlement money until January but that I would probably get quite a bit more money so I can bump up my car audio budget so I can put some more amp to them and just get 2 altenators

So it's "suppose" to be used in conjunction with a thermal rating? The thermal rating of what exactly? I'm just trying to get an clear understanding when a driver has an Rms rating because Root Mean AND the T/s RMS definitions both do not mention anything in regards to thermal?

For the Rms in T/S parameters, the "ms" is actually supposed to be written in subscript, i.e. R_ms where for Root Mean Squared it's all written in standard capitalized script RMS or all lowercase rms. The problem is not everything can format subscript properly or for shorthand people are too lazy, so the R_ms is written Rms.

To make matters worse RMS power is actually an inaccurate term. RMS power was for whatever reason the term picked up by the audio world, but electrically and mathematically it doesn't exist and is a useless term and value. The term we should be using is average continuous power, P_avg because V_RMS * I_RMS = P_avg, not RMS power. RMS power doesn't exist. So in reality the RMS power figure every audio company states is an imaginary value since RMS power isn't a real electrical or meaningful term.

So it's "suppose" to be used in conjunction with a thermal rating? The thermal rating of what exactly? I'm just trying to get an clear understanding when a driver has an Rms rating because Root Mean AND the T/s RMS definitions both do not mention anything in regards to thermal?

For the Rms in T/S parameters, the "ms" is actually supposed to be written in subscript, i.e. R_ms where for Root Mean Squared it's all written in standard capitalized script RMS or all lowercase rms. The problem is not everything can format subscript properly or for shorthand people are too lazy, so the R_ms is written Rms.

To make matters worse RMS power is actually an inaccurate term. RMS power was for whatever reason the term picked up by the audio world, but electrically and mathematically it doesn't exist and is a useless term and value. The term we should be using is average continuous power, P_avg because V_RMS * I_RMS = P_avg, not RMS power. RMS power doesn't exist. So in reality the RMS power figure every audio company states is an imaginary value since RMS power isn't a real electrical or meaningful term.

 

 

Impious-  you're posts always teach me something

Edited December 8, 201311 yr by Leedogg