Is it possible to make det best sounding speaker in the world using only Monacor SP-13/4? Let's find out!

Have a pair of sp-13/4, that was suppose to be used in another project. That project went another direction.
I therefore have a pair of sp-13/4 that i can use to i want. And i want to find out how good sound it's possible
to get out of them.

I dislike following rules and plans. Because it doesn't teach me much.
So the philosophy of this is project is to test out every idea, and measure if it works or not.
There is no right and wrong answer. So don't hesitate to come with ideas.

In a couple of week my nvidia p40's will arrive, to use machine learning is an option.
Got a basement full of old wood parts. The only limit is our mind.

My first idea to test is to see if i can use my coumpter desk as part of a horn.


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Joined 2003
Good luck with this! Lofty goals indeed!

Need to define what qualities is required to be the 'best sounding speaker in the world', i.e. for me it's when the speaker system has me having to decide whether 'Is it live or is it Memorex'. ;) Then there's the issue of how wide a BW? For sure no little driver is going to be excellent at live playback levels over a very wide BW.
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Is this the correct datasheet?

There are no published T/S parameters or a spectrum from the manufacturer. Not a good sign of making the best speaker in the world. But as Adason says, if it’s the only speaker you have, it will be your best.

I see that it tops out at 8kHz so this is going to lack some top end. Being a 5in class driver it is probably capable of some bass if helped by the proper cabinet if we only knew what the Fs, Qts, and Vas was.

I see an article in K&T for the “Very Cheap Trick” speaker with this as the woofer in a two way with tweeter. It sounds like it can go to 70Hz which is sort of ok. Maybe with a back loaded horn we can get more bass out of it.

But if you compare it to other drivers, I would guess you can start with something a little wider bandwidth as the basis of a good speaker and not even aim at being the “world’s best speaker”

Something like the Dayton PA130-8 is probably in a similar class and I like that driver a lot. In a Karlsonator, it sounds quite nice. Maybe a Karlsonator might work here.


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You are on the right track in the 2nd picture. In order to meet your goal, radical measures is needed. I suggest a corner on the floor position and the driver mounted in a triangle shaped (all 3 sides = 63cm) baffle - closed box and EQ. You need to make room in the corners and see to that the direct sound is not obstructed. Enjoy the best speakers in the world. Good luck!

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Best speaker in the world was mostly to grab attention, and maybe start an philosophical discussion about
what good sound is. And of course try to be humorous to show that this project don't take itself to seriously.

T/S parameteres is quite easy to measure, but that goes againts the philisophy of this project.
That is to explore the limits of how good sound i can get out of just this one driver.
Reagular calculations won't get us there. We have to go beyond what we think is possible.

"I see that it tops out at 8kHz so this is going to lack some top end."
I'm planning on using the distortion the element will create above 8khz to my advantage.
Many have a distorted view on distortion. It's not like distoriton = bad!

Recommended reading.

And like i said, i'm planning on using machine learning/AI in this project.
There is quite alot that is possible with ML/AI.

My plan tomorrow is to get this program up and running, to get a better
understading of how the sound propagate from the speaker.
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It wasn’t distortion above 8kHz that I was concerned about but simply ability to make sound there of sufficient SPL. If it falls off you will not have the sparkle and shimmer of instruments like high hats. Loss of highs also reduces the crispness of attack on percussion at lower frequency.

TS params help us to design the aero-acoustic speaker like a horn or TL to a handle the bass. It lets us simulate and use computer software tools to optimize. Reduces a lot of wasteful “cut and try”.
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music soothes the savage beast
Joined 2004
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No curves, no useful design specs. The f3-8000 frequency spec. Nowhere do they say what f3 is.

There are arrows on the image of the 'best sounding speaker in the world'. Just move it to the fr response. Even crossover is partly shown. Which is rather complex for 2way.


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