LX mini sort of , help needed

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Using hivi b3n 3" full range and peerless sds-160F25 6.5 woofer in a LX mini style configuration and need crossover advice and help. SL crosses at 800hz so can someone tell me what components to buy and how to build the crossovers? Zaph uses bsc and notch filter in "best 3" FR but these are open baffle, so don't need bsc, right?
SL states " crossovers can't be done passive and uses minidsp and a butload of amps to get everything perfect, but I'm not sound engineer and don't need perfect.
Started as an experiment into different design. Never tried open baffle or woofer pointing up. I mounted the 3" full rangers and have them taped over the woofers in a temp setup and really like what they do and that is with woofers in coffee can and 1.50 aircoil on the pos side for woofers and a 20ohm resistor on the 3". I know they can sound better but don't know what to do or use for crossovers. Thanks for any help
 
Hey sailormanbigd,

First up, congrats on giving this a go. Now the bad news :)

I'm no crossover expert but if SL uses a mini dsp then it's for a very good reason. He goes active because it's easier than going passive.

There are lots of crossover calculators online. Take into account the sensitivity difference between the two drivers.

You're probably hearing silence because your attempt sounds slightly botched and you're asking a lot for someone to come along and "fix" it but hey, there are some folk here who are very generous with their time so who knows?

Do you have a computer with a sound card? Do you have two stereo amps or a home cinema receiver with line ins? Then you could start thinking about a more active solution or at least control the power to each tweeter and woofer assembly?

Good luck
 
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Well, thanks for reply. I agree I am far from an expert. I have used zaph audio for a couple of builds. All the hard work and designs are his and followed closely. I love the sound of the hivi 3" FR. The price of $8.50 is great too. I happened across S Linkwitz's designs and especially the Lxmini intrigued my interest. I have tried several different enclosures before, like Dbr, winebox, a curtain front affair (forget what they called it)
But never an open baffle, and certainly not an up-firing woofer with a front firing FR. I am building it and listening while I type this. The design and configuration is very nice sounding even without anything close to correct crossovers. I plan to use them as my main speakers for 2.1 living room and movies with a denon 7.1 receiver. I have read a lot of SL's info and the engineering is beyond me. But certainly I can try his enclosure arrangement with a known driver and compare. I can't afford his design, I can't even afford the drivers. What I have is $60 in drivers with similar specs, and approx $40 in enclosure materials. I can build the enclosures no problem. Will be done this week? SL is in another world musically but I have a difficult time with $1000 speakers that have to be driven with 4 amps with 100-200 watts and high dampening? And electronic minidsp, and possibly a preamp all costing 2k plus. He is going for perfection at whatever it takes cost. I am going for great but cheap. I have found diyaudio member AllenB crossover tutorial and am heading down that path now. It is very well written for the beginner. It's just I am still a kid at heart(56yo) and inpatient with a new build. Especially when I cobble it together and it works good. Sorry if I asked to much or too many stupid questions.
 
Sailormanbigd,

Sounds like you're doing really well to me and congrats on making all those builds already, you're doing better than I am!

The only stupid question is the one you don't ask :)

That denon amp could be really useful in this situation? Some guys are using the separate channels of amplification and internal equalization to actively amp systems. You could have the solution to your problems right in front of you.

You should keep going, keep the info coming, throw up some pics. People here love measurements as well if that becomes possible all you need is a calibrated mic and some pc software.
 
Thanks ernperkins for the link. I had seen it prior to going down this road. I have no measurement equipment or knowledge. Again a minidsp is used. If I can't measure then? I listen is all I can do. If it is impossible without dsp and measuring expertise then it might not work I suppose? I can always use the drivers for another build but I think SL's configuration has merrit on its own without micro engineering? Maybe the diy audio people have missed when "good" is good enough in there endeavor for perfection? This is the first open baffle I have tried and so far I am liking it for the way the sound is dispersed.
 
There are three ways to get a pair of speakers:

-Buy them ready made
-DIY Build to a plan engineered by a competent professional
-Engineer and build your own

You are following the third option. The fact that you borrowed aspects of SL's LXminis do not provide any advantage...once you decided to substitute other drivers you are on your own. Then when you decided to go the passive crossover route you are really on your own.

You can build the LXmini to spec with miniDSP for about $650. Then there are the amps. Since you need two channels for your version you're halfway there on the amps. You can muddle about, spend more than half the money and end up waaaaay short of the goal. Or you can drop SL a line, buy the plans and redirect your efforts to construction. Many people can build speakers competently, very few can engineer them.
 
Well Kevin, not all endeavors are blunders. I consider this one a success already! Don't you people read? I have them setup temporarily! I am listening to sweet and airy female vocals and upright bass jazz right exactly now. The vocals are exceptional, the bass is very good representation of what one sounds like. I should know, my father was a pro jazz bassist!!! Geeze, this forum is a tough room with narrow minded people! The majority of output is the hivi3, from above 700-800 hz, the woofer is playing below that, and may have trouble below 40hz if played loud or used for sub20hz music, so are almost all of the small driver speakers out there.I am simply putting together two drivers to play moderate level music in a different configuration. Since zaph already measured it and designed a crossover and I have built two systems with it I know that it plays well, even run full range to a moderate level but bass distorts very easy, so high pass700-800 should help it do better. The 6.5 inch's graph shows breakup above 1100 or so , so 700-800 should cwork there too. The sensitivities are close but will have to check for sure? Thanks to AllenB for helping us poor engineers trying to do something on our own! I think it was Edison who said , I don't consider it a failure, I just found 200+ things that didn't work or something such? Negativism is rampant and contagious
 
On and I have done option 1,2, and now trying my own thing. I built a boombox with the hivi3 and a peerless 5-1/2" buyout sub that turned out well with a 2.1 3116 Chinese amp but that's just a different form factor so don't count as engineering? On wait, that is what I'm attempting to do here! Lol
 
Sailorman,

Reread my post, you will not find the word "blunder" there. So what is it that you are asking for... in several posts you wrote, "...the engineering is beyond me..." and "...I have no measuring equipment..." and yet you are trying to reengineer an already thoroughly engineered speaker system. If you like how they sound now then great, listen away!
 
Kevin, I have been a machinist, and tool designer, and am now an RN. I seriously doubt that most of the people of the world can read thru Mr Linkwitz's vast online material and understand it? I understand concepts in general, but terminology is a different language. Just the theory of sound production is difficult to wrap my head around, really. Air pressure changes? Polar sweeps, rear distraction, wave propagation, et al. But, I can see a picture, or a few, and produce a plausible likeness. I even used dividers to scale the height above the woofer to get as close as I can to original design as I'm sure it matters? I realise that sound of his design is obtained from dspmini crossover and eq and timing, etc. I am not expecting to replicate his "sound" without identical drivers, arrangement, and amping et,al. What I am doing is mine only. The idea that mr L has come upon a different configuration than conventional box speaker's. Is all I'm trying out. I am just looking to save time with a crossover-passive. I will figure it out myself. Sorry I even thought to ask for assistance now as I have used a lot of my time explaining myself. Forget it!
 
Sailormanbigd.....the design of the LX mini poses some very uniques challenges when the drivers are crossed over. The very close proximity, 90 degree baffle offset and the cardoid pattern of the fullrange driver will end up with some significant phase cancellations. I'm not surprised your enjoying them without a crossover.......but once one is added and there's multiple nulls, I expect you'll find a 'hole' in the response.

But that doesn't mean you need a conventional crossover at all. You're listening to the woofer at 90 degrees off axis so in effect you're mechanically creating a low pass filter at the listening position. I would start with a simple 1st order high pass filter at 1khz. Combined with the dipole mechanical rolloff you should be near 2nd order. Try reversing the polarity of the Hivi as we'll to see which sounds better to you.......bu only with the filter in place.
 
Mayhem, thanks so much for your input! I was really put off last night and worked out a temp crossover using AllenB's crossover tutorial without measurements. I currently have a first order low pass air core inducted of 1.50mh on the woofer. It is a cross around 800 Hz I think? This was very helpful as the woofer had some pronounced beaming ( sharpness) in the higher voices, but now their almost gone at mod all. The full range is going to be the tricky one as it tends to be very harsh around 5khz, and the little FR distorts bass very quickly below 100hz. This is known and documented on Zaph's build page. I have an not optimum high pass on it right now( used components on hand). I currently have .8mh inductor wired across + and - (series?, I get them mixed up) with a 22uf cap the same way + to -. This has done well to get rid of the low bass distortion from the little FR. But still need to soften the highs as a bit too bright and fatiguing. But man the detail! I half to quit messing with the crossovers for now because I find myself not getting the up-firing woofer columns built because I am listening too much! Also, until they are built I won't know how they mate up, and in the listenning position. I read SLs page several times and am aware of cancelling nulls, but I think? That they don't leave voids in frequency, but cancel the summing of those FR? I think that is why he said he was able to use only LR2 ? This is the engineering stuff I'm not sure off and thank you very much for your positive input into this mission of discovery. I am very confident that I will get a usable and different result from my previous box designs. I am also certain I will not get near SL's results, or wouldn't expect to. Just some of it? Thanks again.
Can anyone help me figure out how to post pics? When I try it asks for a URL? In my phone I just talked attachments and select the pic and done.
 
I just undid my previous crossover steff and did as u instructed mayhem. It sounds good with just the 1.5 series coil on the woofer and a 22uf series cap on the FR. I have to make 18 concentric rings to make the cone reducer from the 7.17 woofer flange to the pipe of. I have to glue it up, mount to pipe, stuff it and mount FR in proper alignment before serious crossover changes. Thanks again mayhem. Would love to post pics of progress. Any idea how?
 
Done, and now trying pics?

Pics I hope, finished lxmini configured using hivi 3nb fullbrange and peerless woofer. Faux marble column s.
 

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