“High-Resolution add-on tweeter project”
Maarten van Druten
new speakers PureAudioProjects Trio 15 Voxativ are very good
they are a big improvement over my older
I also bought them because they have a modular
design and that they leave room for further
The orginal PuraAudioProjects Trio 15 Voxativ
very satisfied with the standard setup (were the full range
placed between both woofers)
but personally for me
the full range-units are placed a little bit too low this way,
making me feel that the musician is performing
seating, instead of standing.
Therefore I started to
look for a possible solution...
Luckily the holes in the aluminum
PureAudioProjects Trio 15 frame
the possibility to place
in a "Woofer-Woofer-Fullrange" order!
I did placed my PureAudioProjects Trio 15 Voxativ in this "W-W-F"
the character of the music changed a lot.
heard from others that they didn’t like it, but personally I
like it much better.
The total projection is now much bigger,
while the advantages of the earlier “D'Appolito” setup
are now gone…. the current "W-W-F" setup sounds more
lighter more clear,
and best of all another interesting
change is now possible…
Now there is room to place an
“add-on tweeter” at the top.
me explain further:
Note: this is my personal point of view:
Like all other full-range
loudspeaker unit brands, the lowest mid-bass and the highest
frequencies are not the specialism of this type of
The specialty of full range loudspeakers are the mid frequencies.
The Voxativ full range
unit is an excellent
high-end loudspeaker unit
that renders a lot of hyper detail,
and has a very smooth sound
The Voxativ unit can perform very nice high frequencies, and there
there is no need for a upgrade.
So why I'm borthering myself to change my speaker setup?
my PureAudioProjects Trio 15 Voxativ with the Leonidas XO there is
a jumper on the cross-over (XO)
that can be placed in two ways. (“on” or
means "filtered", and off
The "Leonidas XO" from the PureAudioProjects Trio 15 Voxativ
Close-up of the "high-cut" jumper on the Leonidas XO board.
turning this jumper on, (see photo above) the Voxativ full-range loudspeaker get’s
filtered a little bit so
highest frequencies are smoothly muted
This makes the
sound character of the Voxativ even smoother, and I personally
So I decided to keep the
jumper setting “on”.
every change has an (mostly negative)effect on something else.
advantage of turning this jumper “on”, is that the
Voxativ sounds even more neutral,
more fluid and more
appealing for long term listening.
But the disadvantage is
that the frequency above 8000 Hz gets muted with a first order XO
so that the highest frequencies (16.000 Hz and more) are now missing.
Still the music sounds very pleasing, and comfortable, but for
playback High-Resolution music
I'm missing now a lot.
my idea was to place an “add-on” tweeter on top of my
But I didn’t want to intervene the current
On the "X-Fi show" in the Netherlands, I listened to this speaker of the
Dutch company "DAUDIO", called "W1".
The "W1" is a loudspeaker with an active XO, and the sound of this
speaker made a big impression on me.
I never heard such open, wide, transparant and full of hyper detail high
After listening to this fine loudspeaker for some time, I asked someone
of DAUDIO which tweeter they used.
They were very honest about it, and they said it's they used the
"Mundorf hifiAMT 25D1.1" tweeter.
DAUDIO W1 loudspeaker from the Netherlands, amazing sounding
loudspeaker, with the
Mundorf AMT 25D1.1
investigation, I heard that this was possible to place an
additional tweeter to my current
loudspeakers without changing the current XO.
can be done by placing the + and – wires of the “add-on
tweeter” at the beginning
of the PureAudioProjects
The main signal get separated this way, one goes to the
Leonidas XO and the other to
the add-on tweeter.
are no unwanted disturbances this way.
Another design goal I
made myself was that the PureAudioProject Trio 15 Voxativ
may not be altered or damaged in any way.
very cautious about my speakers because I like them very much!
idea was born
One think became clear after this
impressive listening session with the DAUDIO W-1,
I wanted also this superb high-quality high-frequency sound in my room!
So the idea was born, to "add" an AMT tweeter to my current loudspeaker
these Mundorf AMT tweeters are not cheap, (they cost 329 euro a piece) I
decided first to test with another tweeter instead, just to make sure
tweeter could enhance my current PureAudioProjects Trio 15 Voxativ
I had a pair of "Lyric" loudspeakers stored in another room, and I
always found that they had very nice sounding tweeters and also their XO
is very good designed.
So I opened my old loudspeakers and I took out both tweeters and the
are of the brand: “Vifa” H25TG-05 (6 Ohm)
The XO from the Dutch "old" loudspeaker brand "Lyric" the XO is very
well designed by engineer: Jan Smet.
Many aircoils, and only the best quality parts were being used.
The first step - making a
my first idea was to use wood for building the first prototype, but
after some consideration I decided
to use a different kind of material for this
temporary test setup...
have choose to use even more easier to handle material named: “foam-board”
because of the following reasons:
foam-board is flexible in depth, it's two layers of paper with foam
in the middle
so you can place it easily between tight spaces.
(I used 3mm but it can be squeezed
also in an area of 2.5mm)
- foam-board is also very easy to
cut, even round shapes.
Because it’s paper glued on foam, with a
scharp knive you can do almost everything.
It’s also very light and strong, speaker units till 700 grams is no
problem for a temporary test setup.
But my Vifa
tweeter units had very heavy magnets so I had to make a
construction to strengthen
my primary design a bit.
the tweeter would fall back.
working with foam-board goes very fast, I made these test frames
in half an hour.
is being used for this temporary test setup, it’s light,
strong and doesn’t damage
the PureAudioProjects Trio
I placed the tweeter foam-board panel in the
space between the metal frame
and the PureAudioProjects
is very easy to work with, within half an hour the tweeter panels
were ready to test.
It's important to make accurate measurements, so the tweeter unit
will have a good fit.
original Danish made “Vifa” H25TG-05 (6 Ohm) tweeter is attached with nuts & bolts to
the foam-board frame.
test tweeter setup looks very nice :-) because of the weight of
the magnet a
additional "strengthen bar" has to
fitted. Otherwise the tweeter would fall backwards…
The foamboard test tweeter panel can be placed easily, there is
space at the top, between the Voxativ panel and the aluminium frame.
it was time to listen to these “add-on” tweeters.
played DSD music files and SACD iso’s over JRiver Mediacenter using DoP
(DSD over PCM)
My Audio-Gd Master 7 DAC with Amenero module
has been placed in 2X oversampling,
is connected with ACSS cables to the Audio-Gd Master 10 amplifier.
Wow! what an improvement! by placing the Leonidas "high-cut" filter on
the quality of the Voxativ unit improves a lot, but the down side is
that also a lot of information is lost...
By placing an additional tweeter like I did the whole picture has become
I was lucky because the match of Vifa (original Danish units) with
Voxativ seems to be a good one
There was no need to change the tweeter XO, the match was fluently and
The music sounds very well, if I should give myself a number, I should
say it's 95% now.
So I could live with this setup for a long time, and I'm enjoying my
music very much.
But the crystal clear high frequencies of
the "DAUDIO W1" with it's hyper details, that level
has not been reached yet...
So before I will buy two Mundorf AMT
25D1.1 tweeters, I have found
myself a very comfortable temporary solution.
This project will have a continuation soon, because Leon Huijgen himself
is coming to listen to my
To be continued...
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