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I'm really hoping someone on here can help me. A 'friend' of mine built these speakers for me ... but never completed them (fine tuning/crossovers) :crying:

AS you can see in the pictures each speaker has 29 Apex Jr. round ribbon tweeters. 9 Peerless India 5" and one Dayton DCV 8" powered by a SA70 per side (shown in the first three photos) - on the last two pictures there are resistors and capacitors that go in-between in wires from the my amp (Pioneer VSX-1021) and the speakers. I am bi-amping these from the Pioneer. From my Pioneer to the tweeter array therr is a Dayton MPT 3.3uF 250V 5%. To the 5" mid array (coming out of the powered 8" woofer amp) there is a Dayton Audio Grade 3.7Q 10W 2% - nothing else. Should there be???

My friend said while building these: "I think that the ribbons were part of the unintentional slam-dunk right from the whistle. Flat impedance; they highpass exactly where you tell them to. They sound as good as any other quality tweeter, and there IS something there that makes you say "yeah, that's a ribbon". The buyout Peerless woofs are very surprising. The natural rolloff is like a fullranger. That is to say, when they start coming down in the high end, they just...leave...without an audible announcement. No spike, no rise, just smooth until it's gone.I took two stabs at the XO. The first try was from an angle of "expectations": the woofs are gonna need a Zobel (they all do, right?) to facilitate an easy XO, the tweets are gonna need to go at least around 4K 3rd order (they're delicate, right?), etc. What I got was good but uninspiring. The second stab was a ground-up approach, and I was honestly just blown away. Re-read the disclaimer about crossovers above one more time and get your keyboards set to "flame". Here goes: woofs- 3.7ohm resistor, tweets- 3.3uf cap. That's it. Wide open mids, 1st order tweets, simple plate amp variable XO bottom. I'm baffled (pleasantly) myself! A good top-end rolloff from the 5"ers and no impedance spike from the ribbons contribute partially or wholly. My buddy and I went back and forth with a few different sub-ins and add-ons, and wound up agreeing that sometimes you can get away with a trick like this. TWO COMPONENTS! I've got fullrangers with two and a half times that many pieces! I'm confident that with several days of casual listening and leisurely experimentation that I could buff these out further. Probably even take another pass at a proper 2nd order XO with success. But, two things: first, they're gone to live with my buddy four hours away, and next, he's got the Pioneer amp that's got the I-pad interface with 250 million (or so) functions. So, with auto room-correction, auto EQ, auto phase this-and-that, the arrays won't need anything more than a cap on the tweets to be massaged into anything he wants them to do. It's just a dumb luck, pleasant bonus that they did so well with so little."

Unfortunately ... he never completed the 'casual listening and leisurely extermination". I'm torn with dumping these and buying a new set of speakers ... or trying to get the best out of them.

I live in Appleton, WI - would be happy to pay someone to make a crossover that is correct and get these sounding like I expected them to. These speakers sound decent ... but I believe with the 'right stuff' they could sound even better??? When I run Pioneer's MCACC ... I get some seriously funky results telling me something just isn't right. Like some of the speakers are trying to do things they should (crossovers).

Anybody up for a challenge????
 

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Open baffle are a bit harder to get right. My suggestion is three-fold:

1. Get Vance Dickason's Loudspeaker Design Cookbook. It'll give you a good foundation. There are places where you can download a copy for free (I did, but I can't remember where).

2. Download the Tolvan's Edge program so you can see what the drivers are doing on that baffle. It has a function in it to sim for OBs.

3. Go to the diyAudio forum (I apologize if a redirect to another forum is against the rules). The guys there have a lot of experience with OBs, and might better be able to point you in the right direction.

Good luck. And don't chuck them! They could turn out great, but it'll take some work.

Enjoy,
Deon
 

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Instead of going through the many many hours of trial and error , reading , guessing etc etc etc with active crossovers , you can make a simple investment in a MINIDSP 2x8 or 4x10HD + some inexpensive class D power amps like iNUKE or Crown XLS from PartsExpress.com. This will allow you to setup and test an almost infinite set of Xover points and slopes based on what your hearing - and its on the fly....unless you have the time and money to sit around and design your own Xovers and hope they are correct....MiniDSP units also have Gain, Delay and Parametric EQ on every individual output channel.... Definitely giving you the capacity to get the most out of your ARRAYS.....

https://www.minidsp.com/products/minidsp-in-a-box/minidsp-4x10-hd
 
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