Classic monitor designs?

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managed a few more details

speaker terminals
and felt for mounting drivers
not shown, but there's also felt on woofer chassis
quite tedious work, more than expected
 

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hey, I have asked to show more about about the mid/waveguide section
 

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small changes
mid series inductor increased from 0.39mH to 0.5mH
and a zobel in paralel
well, so far I have just used what I could find in waste parts bin :p
so I would think there's still room for improvements

it also helped to mount all driver chassis screws
next to come, diy ribbon tweeter on top

listening distance less than 2meter
speakers 1meter apart
that is tough conditions
and it certainly is a monitor
controlled and precise, and dynamic

playing classical music....BIG positive surprice
and that really was a surprice

btw, finally got the chance to use my Portasol gas iron
and it is a really sweet tool
hard to imagine a (diy)life without it now
 

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I like the use of the cardboard to break up the midrange enclosure volume, how effective would you say it is?
What Focal driver is that?

I don't remember model number on the 5" Focal
I have had the Focal and XT19 tweeter for so long, I dont remember how long
could be 10 years

the cardboard matrix
well, I guess it was just winter, and I had plenty time
but a lot more work than expected
it was a surprice how sensitive it is to added acoustic material
just before assembling I discouvered that the two midrange sounded different
when tapping the surround with a finger there was a distinct 'ringing' on just one driver

I removed all the acoustic material
only put in some very very small bits
then it seemed ok, with no 'ringing'
dont kow why
 
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this xo is ok
values still to come

first time I try without high pass cap on midrange
works quite well
though the 5" is stressed at high SPL
but at normal SPL the best word describing the sound is beautiful and responsive
in a matter of just a few days the sound has gone from forward cold parking cellar sound to a really full mature sound
I could easily live with this, but it may improve further, with more time
 

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this xo is ok
... I could easily live with this, but it may improve further, with more time

Hi Tinitus,

Looks like your midwoofer is a 5K013L. It is a previous version of 5K4211 using polykevlar cone (5K for 5" and Kevlar).

In another thread you are suggesting to use 6dB filter. Also here I can see that you use simple crossover. Without hearing it, I know that I cannot live with such a fatiguing speaker. Yes, the peaks are too bad to be acceptable.

You already mentioned about problem in high SPL, and beautiful/responsive sound with simpler filter for the midwoofer. The simpler the crossover, the easier to get beautiful/responsive sound, but the peaking is worse.

Also, no matter how big the inductor (7mH?, 10mH?) for the woofer and how small the enclosure for the midwoofer. The big woofer in your crossover will produce high frequencies that will interfere with the midrange.

Your standard of acceptable distortion and peaking may change in the future. And you have to change the crossover into more complex one. And that is the real challenge in crossover design.

This kind of 3-way passive crossover setup is very very difficult (easier is to use a real midrange) ;)
 
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Hi Tinitus,

In another thread you are suggesting to use 6dB filter.

You already mentioned about problem in high SPL, and beautiful/responsive sound with simpler filter for the midwoofer. The simpler the crossover, the easier to get beautiful/responsive sound, but the peaking is worse.

Also, no matter how big the inductor (7mH?, 10mH?) for the woofer and how small the enclosure for the midwoofer. The big woofer in your crossover will produce high frequencies that will interfere with the midrange.

6db filter
that is really a misunderstanding
I never suggested to use such
I did however suggest to throw in a 6db filter
but please note that I also said then make it work
the starter 6db filter is just to be able to hear what the drivers do
and then correct it

peaking
there is NO peaking in this speaker
well, there was at first, as you say
it started out pretty awful
but the crossover deals nicely with this
it is smooth now
an it is as you say very important
the midrange is mildly stressed at higher SPL because it plays bass too
thats all
but it stays remarkable clean and honest all the way

bass inductor
it is 6mH
please note that this 12" woofer is 4ohm
the lower impedance results in the inductor being more effective
it is really very nice and smooth, with just a little touch of mild midrange
no peaking at all

on bad recordings the sound is quite ok, and you can still enjoy the music
on good quality recordings I would say it sits somewhere between planars and electrostates

but yes, there's still room for further improvements
 
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xo component values

works nicely
but could still change
zobel on woofer, for one
I still have two 10uf left that might do good :D
and will try bigger series res on tweet
 

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zobel on woofer, for one

and will try bigger series res on tweet

zobel on woofer turned out to be problematic
sounded ok as such
but it caused minor annoying phase issues
I suspect its because of leaving out high pass on midrange

bigger series resistor tho worked very well
as well as different zobel on midrange

revised xo
I will have to try high pass on midrange
 

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Nice build!

thanks!

the ribbon super tweeter really transformed the whole speaker
actually, I can only directly hear the ribbon with the ear close to it
so I guess its also phase related

strangest thing is, with the ribbon added, percussion have improved to the almost unreal
I have never heard this much drum rythm details before, ever :)
its like everything flows freely
someone once said a speaker should sound like breath of air
and thats probably the best way to describe it
kind of like its breathing the music
a really nice surprice