voltage requirements of true power

[Moble Enclosurs 10+ year member]

For the past few days, I have been working on a simple formula for figuring what voltage you will need efficiently, to power your component system or subsystem. This will in turn allow those who have asked the very popular questions before on how to properly match an amplifier and speaker requirements for safe and efficient operation of your speakers.

I'm still testing the theory out, in which I have already tested 7 drivers with grreat results, ranging from 1 watt of true power, to over 500 watts of true power per driver of different sizes from a 2" full range speaker to a 12" subwoofer driver so far. As of now, I have made improvements on the well known half power derivement of rms power from peak power and continuous rating have become more accurate with what I have come up with.

This has been tested on an amplifier with a full response capability of less than 10Hz to over 20kHz and with about 29.80V available so far to utilize without clipping.

The results have been steady with each driver so far, but I'm not sure yet of its capabilities of accuracy with higher power handling over about 100 watts of true power.

I will be posting next, in a few minutes or hours, depending on when I get back, of some results, and possible ideas that we may be able to utilize effectively from this point on. This will hopefully null the questions over time, and I may create a spreadsheet to post for download as well, for free. I do not have pictures of the results to post yet because I am at work, but I will try to work more on this concept tomorrow with pictures and video to back up my theory thus far.

I am excited to see if this works out well, and in the future, I will encourage you to help me with the testing of this on your systems if possible, to see how well it works out. Voluntarily, of course. Hopefully, I will be back on in a few with some more news on this. If it ends up non-consistant, I will post on here that it will be ineffective, and will work to make it more accurate. Talk to you all soon!

Click to read more...

 

[>>SQL<< 10+ year member]

Sounds good but please try to type your findings out in a way that normal people can easily understand.

Many of your posts are very difficult to follow, you may be surprised to hear this, but most of us are not electrical engineers.

I (we) do appreciate the work you are doing but most of the time have no idea what you are trying to say.

Thank you in advance.

 

[Moble Enclosurs 10+ year member]

Sounds good but please try to type your findings out in a way that normal people can easily understand.Many of your posts are very difficult to follow, you may be surprised to hear this, but most of us are not electrical engineers.

I (we) do appreciate the work you are doing but most of the time have no idea what you are trying to say.

Thank you in advance.

Ill make sure to post pictures for you. //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[sacsking916 5,000+ posts]

I gotta agree, your posts are sometimes confusing but always a good read. Tuned in to see results and more testing.

 

[-01limited- 10+ year member]

I tried typing a reply up last night but I guess it didnt go through.

Its nice to have people on this forum that are going for a greater understanding of the sport and actually applying science in it. I like to see that and always look forward to your posts.

 

[duanebro 10+ year member]

I'm watching, waiting to learn more.

 

[Moble Enclosurs 10+ year member]

Ill be able to post results soon, and some info. Just doing more testing and haven't had much time yet today to get anything else done but designs. Ill be back on later with at least something to start with asap.

 

[Tek18 10+ year member]

anything you write makes me feel smart because i somewhat understand where you are going.. but not entirely.. but still.. i feel smart //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

Thanks for the info! i enjoy having very smart people in this field on the forums, always a good read

 

[kramer_212 10+ year member]

you're a smexy man beast.

 

[THATpurpleKUSH 5,000+ posts]

In for the results here, I really appreciate the well educated members on here that are willing to share their vast knowledge. I have learned far more on here than I ever could have imagined in the 2years I have been a member, and I'm aware I've merely touched the tip of the iceberg. Thanks for all you have doing to contribute worthwhile information to this forum.

 

[Moble Enclosurs 10+ year member]

No problem guys. I hope I have been of some help already thus far. Now, unfortunately, I just got home from a long day with the kids, but Ill do some crunching at work again tonight with the numbers, and use various drivers specifications on the market for some figuring over the night, and be back on in the morning for hopefully good news. Again, if you want to be able to test this out, let me know....PM me and Ill give you the specs to set your gains and match everything up, and you let me know what needs to be fixed or if it works ok. Keep in mind that these formulas are for safe operation of the drivers, so those who have always ran them into very high power levels before, even without damage, may notice a difference in output, but this has so far only been tested on ported designs(conventional, not tapped or tapered yet), and with only a mild power range.

Tonight, Ill work on it more and get back to this thread with some news in the morning, whether good or bad.

Smexy man beast.....out. LOL

 

[Moble Enclosurs 10+ year member]

I must mention also that these ideas I have are not far from what has likely been done in the past, but hopefully will shed light on actual power ratings and how they can be utilized more efficiently. That is the idea. Keep that in mind in the future.

 

[Moble Enclosurs 10+ year member]

Ok, bear with me. Ill be posting quite a bit of text right now, so ill break it up into pieces. Unfortunately, there are no pics yet, or any other way to word it for simplicity. If you do not understand it, then I'm sorry....

First, I was doing some tests before work on multiple drivers and got good results. I'm going to first talk a little about the simple concepts of ohms law with audio. We know that we can take two variables of voltage, power, current, and resistance and get the other two results. What we get confused about in when wiring multiple coils together, how that affects the power requirement and draw of current from the source. If you put it all together, it can become quite confusing to some, and be very understandable to others. One of the first things we need to realize, is that we are dealing with multiple frequencies from a driver. It has the capability to provide you with sound from a fairly good broadband of music consisting of those frequencies. That is the first thing.

So, 1. We are dealing with multiple frequencies.

Write these down and put them together to get the big picture

 

---------- Post added at 12:29 AM ---------- Previous post was at 12:28 AM ----------

 

So, what does it mean to have multiple frequencies on a single driver to us? It means that for every frequency, the voltage changes. This is important to know where to start, and where to measure when matching power requirements with supply voltage.

So, 2. Each frequency has its own voltage requirement.

The reason for this is that the impedance of the driver changes with frequency as well. If you have not seen an impedance graph, google it. This can tell you a lot about what the driver will do and need from the amp. What is the main thing that the impedance curve tells us, when dealing with power? It tells use what the voltage is doing.

 

[Moble Enclosurs 10+ year member]

For instance, if you have a DMM, do this test........hook it up to the driver and also hook up the amp. Make sure the driver is not in a box, and is 2ft from all boundaries. What I do, is set mine up on a pod. Use a test tone generator for supplying the amp with different frequencies. For, sub use, start at 150Hz and go down slowly, observing voltage on the DMM. You may notice it get higher the closer you get to the highest impedance of the driver, which will be where the resonant free air frequency is around. This should be the point where voltage is the highest, because the requirement for voltage to maintain constant output is higher....due to higher impedance of the driver. Hopefully that makes sense. And when you pass the Fs of the driver, or the highest impedance point, you will see voltage drop back down again until the amp cutoff sets in, and then continue to drop from cutoff point.

 

[Moble Enclosurs 10+ year member]

This is the relation between impedance and voltage. They work together...

So 3. As impedance increases with free air measurements, so does voltage requirements to maintain linear output.

Knowing this, we can get our voltage from the driver of a maximum voltage and with my formulas, I can figure for rms voltage and continuous voltage for music. First thing to understand about a driver, is the manufacturer specs can be incorrect.

So, 4. Manufacturer specs can be incorrect.

The one specification that they can get right for power ratings, is the max power or peak, because you can physically and thermally calculate maximum for anything. For mechanical limitations, max is just before the mechanics fail to operate or operate improperly. Pretty simple there. And thermally, when the coil reaches a certain temperature where burning of the coil, or melting occurs, etc. Simple there. Because they are maximums, nothing beyond it is useful, therefore, it is easy to determine a max for anything. Its pure physics and electronics.