High-end 3 way dáppolito with aluminiumcone

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Helmuth said:


The movement is the result of the Sd area and frequency and pressure you want to generate.
How lower the frequency then the x must increase to maintain the sound pressure.
Till this isn't more possible the speaker loses acoustic resistance and the resonance frequency appears the Fs of the impedance.

With a BR system the port is tuned to the resonance frequency. At the tune frequency the air in the port resonates in opposite phase with the air in the box. Increasing the acoustic resistance for the driver.

Result the x decreases and the sound is radiated by the port and driver together. You see in the attachment the extrusion of the driver at 1 W and at 20W. The red line is the Xmax. That is the limit for linear behaivour of the motor of your driver.

At the attachment the same driver is simulated one(orange) in a closed box the other (yellow) in a bass reflex.

You can see at the closed box that after resonance the x stays constant and thus the sound pressure decreases. The -3dB point.

With the same driver in a BR cabinet the port increases the air load to the max at resonance so the impedance is then near R-DC and the movement decreases radical.

A good design has many air load because this means it radiates sound.
With a horn you virtual increase the sd. because (sd or throot) * X= Mouth horn * X. This creates a huge air load and thus SPL and good impulse behaivour.

In this design the port generates a good load for the driver so at can't resonate afterwards.
What to many a good or many bass is often a very bad impulse behaivour. So the driver resonates afterwards and creates a fat sound.

The waterfall of this driver is exceptional tight. Tight responding low frequency transponders sound not fat but do give fast peak responses and do not store energy in the system (driver box) and resonate afterwards.

I had back loaded horns they can produce very impulsive clean low distortion low frequency. But to my surprise this bass reflex came close to that sound.


So your speaker has a lot of low frequency to test if that is due poor impulse behaivour your can connect a battery and connect it for a second. Than you shout have a dry bop. If it is more a boinggg than it is a poor performing design.


Regards, Helmuth


Nice work, looks to me though that your impedance curves (air vs electrical) in the listening room is leading a life of it's own ,if you can actually "see" them cones "moving " back and forth.

That ain't music signals being amplified. Looks more like an unstable amp.

Greetz,

Wazzat?
 
wazzat?? said:



Nice work, looks to me though that your impedance curves (air vs electrical) in the listening room is leading a life of it's own ,if you can actually "see" them cones "moving " back and forth.
?
Wat bedoel je.
That ain't music signals being amplified. Looks more like an unstable amp.

Greetz,

Wazzat?

I think that my zhoalu D3 24bit dac does some subsonic low. So you can be right.
I am listening to a tube amp so DC isn't there.

Wazzat Asain (sounds like wattsound.)
 
This design has about 100 hours work in it.
DSCF0363.jpg

The price is under 400euro for one speaker.

I think the design can be upgraded with the fountekFW146 The mivoc is low distortion and has a warm sound to it but I think than aluminium cone will reveille more details of the music. Two Fountec drivers cost 70 euro more than the low cost mivoc drivers.

An externally hosted image should be here but it was not working when we last tested it.


Regards helmuth
 
Hi music lovers,

Yesterday I was at Pauls place to listen how the speakers sound at his place. Was great, he has the same music taste as me. The room was small 4mtr and long 10mtr with high sealing. The high sealing had a positive effect on the sound stage. It sounded big :cool:

I was interested in how the speaker at listening position measures compared to my own living room. I must say I was surprised by the similarity of the results.

I post here my result I see never results of others I think every one measures the same poor results to the fact of flatness and so they do not dare to show them. But I have now problem with facing the reality, because the speaker is designed very well.

This is the result measured at the listening position about 3.5mtr from the speaker. Stereo MLS measurement 1/3th octave. FFT window 85.3msec 4096 measurements. Used software HBX-V6 and calibrated omi mic EMC8000 16bit sound cart.

pbthuis.jpg


+5dB 22Hz-13kHz If any one has problems with it show me your measurement at listening position stereo. And used software FFT-window and used filter to smooth. I am eager to learn.


Here is Paul my colleague how owns the speaker. He will write a review soon.
DSC00169.jpg


Regards Helmuth
 
wow

Hi Helmuth, I would like to thank you once more for building me the best sounding pair of speakers I ever owned!

As you know, I wasn't satisfied with the sound of my Harman Kardon Festival surround stereo set with 5.1 JBL speakers!
At first I denied it but after a while it became very clear to me that I had to get rid of the annoying surrogate surround sound.
What a mistake did I make to ever buy one of those sets.

I was glad to hear that you preferred the large volume stereo speaker sound as well and think that you succeeded in defining the ultimate speaker sound for me. Well balanced high- and midtones, but a fat, yet precise base, because rock'n roll has to be in your face, right?!

The looks are great as well, I think that the light coloured berch wood combined with the black front with recessed aluminium tweeters and carbon fiber woofers really are an asset to my modern interior.

After a couple of weeks listening to them (poor neighbours!) in combination with my old JVC super A Amplifier, I have to say that I am very pleased that I can enjoy the "live" music experience again. As if I am in a concert hall with the musicians! Because of the well-defined and balanced tones I can also enjoy the sounds of various intruments floating into my living room. This would never have been possible with my budget had I bought speakers in a hifi store. Thnx 4 this and hope you can make many other people happy with your craftmanship!

I would be glad to recommend.
:worship:

Best regards,
Paul
 
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