"Vopli" small computer monitor system VifaNE/VisatonKE

[r-carpenter]

So my missis has been asking me for a near field computer set up for quite a while. I wanted to create something special but most of the drivers in the collection are 7" woofers or larger. Recently I have measured Vifa NE 149, graciously provided by AJ and was very pleased with it's performance. Based on the measured data of the NE149 I've decided to try the smaller brother NE123. http://www.parts-express.com/pe/show...umber=264-1128
Just received them today. Uber motor looks the same as it does on NE149. The copper ring is visible behind the coil former. I should post the pictures of the motor later.

The story with the tweeter is a bit different. Initially the Visaton 25KE was meant to be used in a commercial system with the Excel Magnesium. The hopes for it's performance around 2k were high and unfortunately well unfounded. The distortion profile limits the passband to 2400-2500hz which is not exactly great for ceramic dome costing $150 a piece. They didn't sell on ebay and instead of selling them for peanuts I decided to use them for my own system. Mind you, after 2500hz the performance is stellar but so it is for a bunch of other tweeter costing less then half. Let it be the constant reminder to me. :rolleyes:
No, I don't hate it, it'll play tunes.

The combo almost begs to be used as a topper for a 10" woofer in a 3-way tower but my passion for line arrays makes a conventional 3-way design sort of, not fun.
With this justification I am embarking on the small quest with limited space in mind.
The data will be posted as I go alone with the build.

[[email protected]]

Re: "Vopli" small computer monitor system VifaNE/VisatonKE

Look forward Roman.

[r-carpenter]

Re: "Vopli" small computer monitor system VifaNE/VisatonKE


Visaton ceramic tweeter.
this data is measured on a wide baffle. Not too bad. Frequency response is fairly flat. CSD is clean enough. The distortions are so so. It actually sounds a bit rough till the slow sweep gets well over 2k.

[r-carpenter]

Re: "Vopli" small computer monitor system VifaNE/VisatonKE


the tweeter features integrated CR for the FS impedance bump and it is really so. Not that I couldn't do it myself bit it's there already. One of the graphs shows Visaton supplied FR and Imp.
Thanks to the Visaton. A few more pixels and that graph could qualify as an artwork.

Visaton claims a 1800hz crossover point. Not sure if it's possible or even advisable. I'd guess I should have the fundamental response at 1800hz at list 20-30 db down which would warrant a higher crossover point (depending on the slope of course).
In general I do prefer a bit of hotness on the top octave so the natural upper octave bump, isn't an issue for me.

[r-carpenter]

Re: "Vopli" small computer monitor system VifaNE/VisatonKE


Mrs. liked this veneer. No argument there.
Going to do a small curved cabinet and probably veneer it in the press all together.

[Squidspeak]

Re: "Vopli" small computer monitor system VifaNE/VisatonKE

[ATTACH=CONFIG]38764[/ATTACH]
Mrs. liked this veneer. No argument there.
Going to do a small curved cabinet and probably veneer it in the press all together.

Roman, beautiful veneer. What is it,I'd guess figured walnut. But why do another budget
build?

[r-carpenter]

Re: "Vopli" small computer monitor system VifaNE/VisatonKE

Roman, beautiful veneer. What is it,I'd guess figured walnut. But why do another budget
build?

space constrains ....... :p

[r-carpenter]

Re: "Vopli" small computer monitor system VifaNE/VisatonKE


this is the merged response of the driver. Not going to be hard to work it at all.

[Squidspeak]

Re: "Vopli" small computer monitor system VifaNE/VisatonKE

space constrains ....... :p

Roman, that was meant
as a joke. I would not consider your project in the budget build category. Anyway what's
the veneer?

[kenny_k]

Re: "Vopli" small computer monitor system VifaNE/VisatonKE

Merged without a XO?

[r-carpenter]

Re: "Vopli" small computer monitor system VifaNE/VisatonKE

Mike, I understand. But I do like the bigger speakers ;)
The veneer is burl Walnut. Sometimes this variety is called Bee's Wing burl.


So, here are the distortions of the Vifa.

Mic was positioned at 15cm away from the driver and the voltage applied is in the file names.
This is a very wide pass-band little woofer.

Merged without a XO?

"Near field" and "Far field" responses are merged. There's no crossover, just a driver on a large baffle.
SPL is absolute. Far field is taken at 1m, 2.89v with 8msc gating. Near Field was done at 2cm, 500msc gating. Merged at 700hz.

[r-carpenter]

Re: "Vopli" small computer monitor system VifaNE/VisatonKE


and the impedance.
So far, very little to complaint here. May be a bit more sensitivity for a dedicated mid in a 3 way but on the other hand this little woofer will not need a complex crossover.

[r-carpenter]

Re: "Vopli" small computer monitor system VifaNE/VisatonKE


made a bit of a progress. Boxes are made from left over 3/4 BB ply. Going to round over the corners and stretch the fabric over them. Something like grey or black Ultrasuede.
After the fabric is glued on, I will make side panels. Port will be facing "down" and located behind the tweeter.
Going to use these http://www.parts-express.com/pe/show...number=300-249 for mounting

[bkeane1259]

Re: "Vopli" small computer monitor system VifaNE/VisatonKE

I just used these mounts for a pair of Pioneer BS21s (mounted to wall). Even though I was pushing it a bit on the weight, the mounts work really well. They're basically $9/ea. - come in pairs.

http://www.parts-express.com/pe/pshowdetl.cfm?&Partnumber=240-828&scqty=1

[Mayhem13]

Re: "Vopli" small computer monitor system VifaNE/VisatonKE

Like the wall mount plan.......no woofer slap off of the desktop and far off the wall to eliminate most midbass modes....might even be just enough of a bump to extend the F3 if you can measure it mounted and tweak the port accordingly.