Vota 3Article by Udo
As soon as Vota 1 and 2 were featured in the magazine the readers were already calling for an extension. Please develop a home cinema system with even more possible choices was written into my to-do list. A look at the original survey revealed that nobody had asked for it originally, but often further requests are generated once a product has hit bulls eye. Well, if you ask me I will deliver, Appearance and design of the Vota 3 have been decided on quickly, you were even be able to marvel at the CNC milled baffle. Now a few weeks have passed and the reader had to exercise patience. Finally the wait has come to an end and the Vota 3 has been smoothly integrated into the family of fulfilled reader requests.
The composition of the chassis, the housing size and its format are no surprise: double the volume of Vota 1 and of course two reflex channels. These channels are symmetrically arranged around the two AXT-05 and the centrally seated NeoCD 3.0. A Sketchup-drawing in the Vota 1 style was quickly drawn up and the wood purchased. The housing construction should have been actually finished within a few minutes.
Yet the "but" was already waiting in the warehouse of my wood wholesaler, from whom I only wanted to buy one 22 mm MDF Duetta baffle for a delivery to China. There a stack of MDF coated on both sides with white priming foil was lying around. These immediately shredded my Vota construction plan mercilessly into small pieces. This was the reason for the long delay. I also wanted to use my new CNC milling machine for this cut. A blunt cut could have been provided by any DIY store, but we wanted to do something special, the wood kit sawed on a mitre. One should be able to stick it together with impunity in the holy living room, (almost) dust free and even while being all thumbs. We had to consider a lot of new things and even entered a few dead ends.
First I modified my cicular table saw. I wanted to use it to cut the necessary mitres onto my cuts. Handheld tools have the strange peculiarity to perform precise 45 ° cuts only when any kind of wobble is avoided while pushing the panels. Limit stops everywhere and flutter free sliding table are common in the professional carpenter's workshop, but they do not come cheap. It was also not possible to perform the necessary additions to and modifications on my hobby saw. I had to do some additional thinking. I purchased a hand-held circular saw with a guide rail, as it has been highly praised to do this kind of work in various online forums, at the DIY store. Its manual looked promising. At home the tool already fell off the rail at a 30° angle. In addition the 1.4 m long rail was way too cumbersome for short cuts. In exchange the DIY store manager gave me a beautiful, heavy milling table with a lathe already built in. The lathe could be precisely set to the required height using a lifting device. As the putting in of the milling head could be accomplished only with considerable effort and slightly bleeding fingers, I returned it and got my money back without further ado. But the time was lost nevertheless.
Only now I was able to concede that a CNC milling machine could handle all these tasks easily. The main deterrent so far had been the long time perceived it takes to cut alongside the long edges. On a self-guided machine you do not really realise that cutting to size takes at least as much time as you are not only occupied with just watching. Tentative sawing, readjusting, setting new limit stops and pushing wood arund helps the time pass much quicker than doing nothing.
To facilitate glueing for someone inexperienced in handicraft, usually dowels or lamellos are integrated into the cutting edges. I found this method too simplistic for a CNC mill, so I just invented the stop mitre. Here only part of the cut surface is angled at 45 °, the other part serves as a natural stop. The photographic documentation of the assembly that is shown now precisely illustrates this.
Apart from the reflex boards, because a guide was being milled on the inside of the front and the sides, all parts of the Vota 3 were put together on a flat support. It would have even protected the glass table in the living room from the glue, if I had chosen to do the assembling there.
The stop mitre can clearly be seen on the two detailed photos. On the right hand side only a 45 °-bevel can be seen, on the left hand side an additional ledge, which after folding will rest on the neighbouring plates, is seen. It raised a lot of dust until finally the calculated settings agreed with the real world. Further comments I wrote below the pictures. If you (left)click on the first photo an image gallery appears that includes these comments. If you are not an avid reader even the self-explanatory pictures may suffice. Those who cannot even find the reports, would definitely have already been satisfied even without the pictures.
The construction of the boxes took roughly ten minutes although taking the photos delayed me a bit. The after treatment for both boxes including twice the application of varnish did not take up more than half an hour. The amount of dust created was so low that on occasion I did not even have to remove the camera out of the room. Sure, some readers have already wondered about the strange tweeter cut. This is caused by the fact that a ribbon is long in one direction, but narrow in the other. Therefore it must be screwed into the dwelling and turned appropriately to the site of installation.
Installing the crossover of my Vota 3 went almost as fast. This was expected due to the specifications given by the Vota 1. Only the design of the tweeter placed in the middle between two 15 cm openings had to be taken. This did not require any new insights, I was able to transfer the toplology 1-to-1, the figures had to be adjusted to the parallel circuit. Measurements were used to do that. With a DB level of 93 at 2.83 the Vota 3 is one of the loudest small boxes in the non PA range. An output of half the maximum volume at 60 Hz, it just calls for an impedance correction for tubular listeners. Even without any comments the charts provide information about the immaculately crafted circuit.
Now only the usual diagrams, although not many readers are interested in them, are missing, but a presentation of a construction cannot be complete without them. Hear you are! ®
Measurement diagrams Vota 3:
|Frequency and Phase||
|Frequency Response below 0 / 30 / 60°°|
|Harmonic Distortion (THD) for 90 dB||Step Responset||Waterfall|
For the sake of completeness we have again photographed the mounting and installation of the crossover. One bag of Sonofil per box was sufficient. The two mats were centrically folded and placed along the side walls to the left and right. The entrance to the reflex channel should not be covered.
Because a center is mostly placed horizontally, we have of course also done measurements in this position. The tweeter was rotated 90 degrees inside the cutout, the crossover was left unchanged. At a listening angle of greater than 30 degrees the chassis layout causes a sharp drop around 3 kHz. At three metres distance from the center the seating area is reduced to a sofa width of barely four metres. At an angle of less than 22.5 degrees three people can be splendidly filled with sound and there is enough space left to freely move the arms. None of them hears women when in fact men talk on the screen. At least this must be the case for at least some people who in various forums are constantly warning while pointing the finger against symmetrically built and horizontally placed centers. The diagram shows the frequency response at 0, 10, 15, 25 and 30 degrees, respectively. Reflections from the walls or even the at least four other boxes playing along have been completely disregarded. Now bearing in mind that in addition to the sound there is also a picture showing our brain a person in action, I wonder who will perceive drops in the narrow band for each individual speaker. Let’s leave this for now, they have heard it clearly - they have again and again written it at the top of their voice.
Now it is time to talk about the listening experience. I do not own image or movie, but I own two speakers where I have installed the tweeter upright on a destiny-hybrid to enjoy the sound in stereo. At the Vota 1 presentation I was reproached that I only delivered a description of the sound of Vota 2. Now I expect to get hammered even more. As then I could only have written: "The Vota 1 sounds like the Vota 2: It just has less depth since the bass is missing." Today I can only write that again no new insights have been discovered for the Vota 3 as it consists of the same chassis and nearly the same crossover inside a housing double the size to accommodate two 15. Well, it is a bit more powerful than the Vota 1 as the membrane surface has doubled, but there is no change to the depth. Subjectively, however, it feels as if there is some improvement as more air is moved. Therefore at this point I would only like to point towards my sound experience gained in the Vota 2 test. Vota 3 likes rock, too, can large it at a proper sound level, but classical music, jazz and Top 40 do not sound unpleasant on it either. Three pieces at the front and maybe two at the back they literally impress when used as a home theatre. In the near future we will add an active subwoofer. A reasonable compilation would be two Vota 2s and one Vota 3 at the front, twice the bass piece Vota 2 in Bi-amp mode at two separate channels and up to five Vota 1-3s that each run without the high-pass. All together they promise a top-notch home theatre system with stereoamp that also renders music at a sophisticated level close to the blues class. It does not quite achieve it due to my subjective requirements that can be looked up in the column "About loudspeaker construction".
Specifications Vota 3 Front or Center
|Chassis||2 x Gradient AXT-05||19 mm MDF woodlist per Box:|
|Fountek NeoCD 3.0|
|50,0 x 26,0 (2x) lid/floor|
|Sales||Intertechnik, Kerpen||16,0 x 26,0 (2x) sides|
|Construction||Udo Wohlgemuth||16,0 x 46,2 (1x) back panel|
|Functions principle||Bass-reflex||16,0 x 44,2 (1x) front panel (baffle)|
|Nominal impedance||4 Ohm||16,0 x 10,0 (2x) reflex board|
|Terminal||T 105 MSAU|
|Insulant||1 bag Sonofil||Milling depth:|
|Bass-midrange: 4,5 mm|
|Approx.cost per box:||Tweeter: 4,8 mm|
|Kit without wood||
159 EUR incl. VAT
|Impedance correction||6 EUR / USD||
Wood cutting: 15 EUR / 19 USD
You can order the Vota 3 at Intertechnik
Expandability of the Vota kits: