ViPeR: Mini-Array ( w/ "buyout" ribbon)

[jeff_free69]

ViPeR

This project has been brewing for a while but is now well underway.
Since its April 15th, I figured I'd take the time to thank my uncle (Sam) and Turbotax for giving me enough of my money back to finance this!

I'm trying something a little bit different here, with the assistance of Roman (r-carpenter) and his experience in array systems. Hopefully he'll keep me out of trouble on this one (thanks, Roman!).

If you've ever been to his shop or seen photo's of the NY DIY events you've no doubt noted the full size arrays looming in the background behind our builds. They have a way of projecting the soundstage and filling the whole room. So of course i have lusted after them for the last few years (even though I knew they are too massive for my room).

So my take on them will be a "Mini-Array" (about half the size)

We all love to gawk at photos, so here's a shot of some of the components to get the ball rolling.

[jeff_free69]

Re: ViPeR: Mini-Array ( w/ "buyout" ribbon)

ViPeR is :

• A 3-way design, and stands for '"Vifa - Peavey Ribbon "

• ...Not really "mini". Its going to be a 2-piece floor-stander, about 4 ft high.

Drivers

• Tweeter: Certainly not what you usually think of when you see the term "buyout" . But I'm using the buyout Peavey Ribbon , which is essentially the same original Fountek 5" ribbon , so I couldn't resist the bargain http://www.parts-express.com/peavey-...7-ohm--299-465

• Mid-bass: Vifa NE123 http://www.parts-express.com/vifa-ne...aker--264-1128
  These 4" wood fiber drivers are from the same family as the 5" that Roman used in his "Bamboos" (shown recently at NE DIY). They impressed me with their smooth-as-silk midrange on even the most challenging material.

• Bass: Bringing up the low end will be the very sexy Dayton RS270, crossed over around 200-300Hz, very possibly bi-amped.
  (thanks again to Roman, for contributing the large, heavy duty bass bins!).

I'm going to repurpose some Dayton 1 cuft Curved Piano Black cabinets. So with a lot of the dirty work done, there's no excuses left!
(glad i got these on sale a couple of years ago!)

http://www.parts-express.com/dayton-audio-mtmc-10bk-10-cu-ft-mtm-curved-speaker-cabinet-gloss-black--302-751

This cabinet is 22" high and will accomodate 4 x 4" Vifas.
and 3 x ribbons (and yes, the odd number will be an interesting bridge to cross)

APPLICATION:

• This will be for a personal/project recording studio control room (which doubles as my serious/fun listening room).

• They are intended to replace my Zaph SR-71, which have served me well for the last 5 years. I'm hoping to keep their clean detail, but have the midrange a smidge more forgiving and less analytical. Their bass extension is very good, but naturally still somewhat affected by the room, even though it is well treated. Preliminary testing shows that keeping the woofer closer to the floor will help even this out.

• They are not intended for near-field use; I usually work about 7-8 feet away.

• Any array will tend to be directional, especially with these tweeters which are very vertically directional to begin with. But I've considered that; since my location doesn't usually change much, it could actually be a positive thing by reducing the level of reflections. The sweet spot will be a little wider behind me, enough for 2 or 3 people, which is all there is really room for anyway.

[jeff_free69]

Re: ViPeR: Mini-Array ( w/ "buyout" ribbon)

reserved cabinet details....

more photos coming !!

[mzisserson]

Re: ViPeR: Mini-Array ( w/ "buyout" ribbon)

Jeff, this sounds like fun!

[jeff_free69]

Re: ViPeR: Mini-Array ( w/ "buyout" ribbon)

Things have been moving along, even if the thread updates haven't ..

First up was a sanity check on the buyout ribbons. Before I commited to this I bought a couple of the ribbons, mostly out of curiousity. Roman did some measurements on one back then.

http://techtalk.parts-express.com/showthread.php?241176-Peavey-RD-1-6-Versarray-Ribbon-Tweeter-and-Fountek-Neo-X-3-0-Ribbon-Tweeter-Testing

The Peaveys seem right in the ball park of what could be expected.

Now that I have 6, i did a very quick test of my own. The news included a slight disappointment - while the general shape of the response is very close, the absolute level from unit to unit is not insignificant.




4 of them are within .5 db, but 2 are about 2 - 2.5 difference.


For this project particular I am not that concerned for 2 resasons.
1) These are very efficient and need to be padded down anyway
2) Roman has mentioned that he wants to use some shading between them.

But if you're looking for a matched pair , there's a bit of luck involved.

[jeff_free69]

Re: ViPeR: Mini-Array ( w/ "buyout" ribbon)

Fitting 4 mid-woofs and 3 ribbons is going to take some very careful planning,
and possibly a shoehorn...





Here's the layout , getting ready to make swiss cheese of the baffle. Fortunately its 1" thick.

[jeff_free69]

Re: ViPeR: Mini-Array ( w/ "buyout" ribbon)

SWISSCHEESE!

Man that's a lot of holes

But no major messups (mangled drivers or fingers )

I'm thinking I may have to reinforce the back...

[jeff_free69]

Re: ViPeR: Mini-Array ( w/ "buyout" ribbon)




This is looking pretty cool loaded up!

[r-carpenter]

Re: ViPeR: Mini-Array ( w/ "buyout" ribbon)

Sweet!
I wouldn't be concern with slight difference in the SPL for this configuration. Let's pick the less sensitive ribbons for the top and bottom and more sensitive for the center locations.
I've been thinking of this particular arrangement myself for a long time. Large line array like mine can be wonderful but tend to smear central image a bit (which is fine because on the majority of events I go to, there's no defined central image). This mini array I'd hope would accomplish 2 things. One, it would still have a closer to life-like virtual imagery but without over-blowing it and two, dynamic range similar to large array. We'll see.
Jeff did all the legwork so if I can help with measurements and tweaking, by all means.
I would wire the woofers series/parallel so the summed up impedance equals to a single unit but run each set of tweeter wires separate and marked so we could try different configurations with and without shading.

[Sydney]

Re: ViPeR: Mini-Array ( w/ "buyout" ribbon)

the majority of events I go to, there's no defined central image

Yeah not everybody gets the optimum seat ;)

but run each set of tweeter wires separate and marked so we could try different configurations with and without shading.

:applause:
From experience: this adds flexibility for a minimum of expense.

[kenny_k]

Re: ViPeR: Mini-Array ( w/ "buyout" ribbon)

That baffle reminds me of a the NYC subway during rush hour. ;)

[badman]

Re: ViPeR: Mini-Array ( w/ "buyout" ribbon)

All those holes make for a pretty weak baffle- I'd suggest using a 3 dowels from the front baffle to the back, on each of those triangular sections between all the cutouts. Also, get those buglehead screws out of there, they'll deform the driver holes and make a worse mounting over time. Panheads are a much better choice, or socket caps with washers, or anything that can be made flat to sit in the cutout. Even small scale hexhead w/washer can work nicely.

[6thplanet]

Re: ViPeR: Mini-Array ( w/ "buyout" ribbon)

Wow, that's gonna be a stunning array! You'll love the RS 270's, I'm currently using 4 of them. Two in a 2.3cf box sealed. Nice tight bass!

[r-carpenter]

Re: ViPeR: Mini-Array ( w/ "buyout" ribbon)

Any progress Jeff???
Common, hurry up!

[jeff_free69]

Re: ViPeR: Mini-Array ( w/ "buyout" ribbon)

Any progress Jeff???
Common, hurry up!

OK BACK IN BUSINESS !
(had to do some business travel and focus on work; now on to more important things like speaker building and summer concerts!

... All those holes make for a pretty weak baffle.....

That became immediately apparent, so I knew there was more work to do....

First thing I'm doing is gluing a "spine" down the center.

( its not glued in yet, because I'm debating how much more breathing room needs to get chamfered out for the 4" vifa driver.
The baffle is 1", so it s a pretty thick hole. once the spine is glued on, accessing the chamfers again will be impossible)

I may also add similar horizontally "ribs" between the drivers.. ( but, again, don't want to interfere with their breathing)

Then I'll wedge in a dowel or two...
[edit] - a second thought is -
... make the spine go all the way to the center brace ( about 6-7" Deep) and attach it there. but then that piece has to be PERFECTLY cut