# Project Linkwitz Orion Evolved and on a budget



## 2010hummerguy

Greetings home audio fans! So I have always wanted to build my own pair of home speakers and my biggest inspiration has been the Linkwitz Orion:










ORION challenge to DIY

However, it has always been hard to justify setting aside $$$ for 8+ channels of high end amplification, electronic x-over and then the astronomical prices of SEAS/Peerless drivers. Not to forget the cost/time needed for the enclosure itself. Until now...

I got a screaming deal on a pair of SEAS W22EX drivers last weekend so it has officially begun:










For the tweeter, there is now way I am going to drop $1000+ on two pairs of Milleniums. Enter the BG NEO 3 PDR:










Bohlender Graebener Neo3-PDRW Planar Tweeter w/Back Cup 264-735

Excellent off-axis response and removable back cup make it a good match for open baffle use. And affordable! Plus a little different, great for street cred 

As for the woofers, I am not keen on spending another $700 on the Peerless XLS woofers. However, Peerless has a driver that happens to be a be better suited for open baffle use and costs less than half as much, the 10" 830668:

Peerless 830668 10" Paper Cone SLS Subwoofer 264-1110

Not as much Xmax as its XLS big brother but QTS is much higher and the price is right. Two per side in an H configuration with 120 watts gained down should do well.

The other option I may try is the Eminence Alpha 15". I am also a big fan of the Jamo R909 and the Legacy Whisper so these would play into an interpretation of either design. Plus a wall of 15's looks pretty cool 










Eminence Alpha-15A 15" Driver 290-407

Jamo R909:









Legacy Whisper:









I'm in a small high-rise right now but my condo is supposed to sell by the end of the year...if it does, I'll be more inclined to go the 15's route since I will be moving into a large house, perfect for the large format sound that the 15's will deliver.

Now, onto the amps and crossover. For a crossover I'll use a DBX 234 proaudio unit:










These are on ebay buy it now for $129 refurb'd and just need mono 1/4" to RCA adaptors for home audio use. Very flexible and only one required for a pair of 3 way channels. Very good feedback on diyaudio.com regarding noise floor and performance.

As for amplification, there are a number of amps I am looking at and it all comes down to the best deal. I have an offer in on a pair of Rotel 6 channel amps locally here but I have a feeling it will fall through. If it does fizzle, I may end up with a pair of Elan (Sunfire) Z660 6 channel amps, one channel per mid/high and two channels per woofer (60w per channel or 120w bridged). Or a pair of Adcom GFA 535's for mids/highs and a 545 for the woofers. The great thing is that all of these combinations are $400 or less all day long on Craigslist or Ebay. MUCH less expensive than anything in Linkwitz's plans but all comparable performance.

Next week a contractor friend of mine is taking me to a local exotic wood shop where I will pick out the mid/high baffle. Everything else will likely be 1" MDF, likely piano gloss black but I am still looking at other finishes before committing to that.

And there you have it. I'll be sure to continue posting updates as the build progresses. Stay tuned!


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## chad

what is the recommended crossover?


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## 2010hummerguy

Linkwitz calls for a 4th order 24db/octave at 120hz and 1440hz, 5khz notch filter for the W22. The slopes are easily accomplished with the DBX unit but I will need to make the notch filter myself. I will probably play around with the 1440 xover, I've read that the Neo PDR tweeter can go as low as 1200hz open baffle but is better closer to 2khz. I just need to stay away from the 2.5khz breakup with the W22.

The other option would be a pair of 2x4 MiniDSP's and then crossover/notch with those. Or a single 2x8 MiniDSP.


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## chad

You could do the miniDSP but I like the DBX idea, and with the change in components, the notch may not be needed or likely change.

Wait, that out of band notch is being used to correct phase.... nice, don't see too many out of band notches used around here. Effective way to do things.


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## 2010hummerguy

You know, I never actually understood why they did that until you mentioned it now. Learn something new every day!


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## chad

We do it quite often in pro audio, kinda works the same as an all pass filter. just threw me for a loop for a second to see it posted here 

Almost wondering if finding a second hand DCX2496 may be an option, rumor has it 200 bucks can be an attainable number.


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## The A Train

All new drivers would need an all new xover. The minidsp is a good alternative with some extra goodies in there to help tailor the sound to your environment and personal preference although, I havent had much of a chance to play around with it to know what filters it has (orders, slopes, notch, zobels, passive assist etc.)


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## chad

mini DSP has weaksauce I/O... granted it's just gain staging but it's rather dependent on his amplification as to if the mini DSP can drive them to full output. I know that the MiniDSP would have a hard time driving my amps without help. one reason I have decided not to use them.

The notch WILL be different because of the tweeter change, especially since it's setting up phase relationship and the drive source of the tweet will be at a different place in relation to the woofer's drive source with the planar.


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## WLDock

Great thread! I have been wanting to build a set of Plutos myself. Now your build has caught my attention. Looking forward to this....


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## 2010hummerguy

Great news, I picked up a pair of Elan Z-660 amps for dirt cheap tonight. They are manufactured by Sunfire and normally used for whole-house audio. Good specs and very flexible. Mixed reviews but most people are listening to them with crummy in-walls so I am taking my chances, especially for the price.

And my SEAS Excels came in the mail today. Time to go wood shopping!


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## chad

I bought a carver PM1.5 mono... it's Bob Carver week!


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## 2010hummerguy

chad said:


> I bought a carver PM1.5 mono... it's Bob Carver week!


Nice, that is a great amp.


Quick update, I finally decided on Vifa XT25 tweeters paired with Monacor WG-300 waveguides. Four total, one front firing and one rear firing per side (rear will be out of phase similar tothe latest Orion design).

I also ordered the dbx crossover and all cables/hardware needed.

I have been looking at preamps but may just open up my Denon receiver to find the preamp section and route it directly to the crossover.

Hopefully I will have everything together before my 2 weeks off at Christmas.


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## vactor

i built the Plutos as well as the Orions. both are fabulous designs and sound simply amazing. you will not be disappointed. i never had them in the same room, but the Orions were just better at the dynamics, but both had the most insane imaging and "lifelike liveliness" i have ever heard. the man knows his stuff. period.


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## WLDock

vactor said:


> i built the Plutos as well as the Orions. both are fabulous designs and sound simply amazing. you will not be disappointed. i never had them in the same room, but the Orions were just better at the dynamics, but both had the most insane imaging and "lifelike liveliness" i have ever heard. the man knows his stuff. period.


 Yeah, that is what I keep hearing, I have never heard either of the designs. I was considering the Plutos just based on cost. However, if this project turns out well I may consider a budget Orion build. My home audio options suck...I reall need to start working on a nice reference system.


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## ecbmxer

I've always wanted to try one of those designs! One day maybe. I like your choice of components. Will you have any EQ ability? (obviously not as critical as in a car, but still)


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## 2010hummerguy

ecbmxer said:


> I've always wanted to try one of those designs! One day maybe. I like your choice of components. Will you have any EQ ability? (obviously not as critical as in a car, but still)


Trying to go sans EQ to begin with but I may need EQ for the subs depending on what design I settle on. With the XT25's and the SEAS crossed over at 120hz and 1800hz, I don't expect to need any EQ for them.


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## mmiller

This is going to be a great build, looking forward to it!!!!


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## xanderin

Subscribed.... Interested to see your X-over choices. I would probably go passive to only use one channel of amplification.


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## 2010hummerguy

xanderin said:


> Subscribed.... Interested to see your X-over choices. I would probably go passive to only use one channel of amplification.


That was definitely a consideration but building a pair of 3-way 4th order crossovers was starting to get pricey and then there is no room for easy customization should I not get it right the first time. My Elan Z660 6x60 watt amps arrived today so amplification is now covered. My dbx 3-way crossover should arrive this week, leaving me with only the preamp/processor to figure out.


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## 2010hummerguy

Crossover arrived but my clients have been keeping me busy with their end of year scamble to exhaust their budgets so I haven't been able to invest much time in a preamp search. Thankfully I have the next two weeks off and will be building test baffles for the tweeters/Excels and looking for a preamp. 

No decision yet for woofers but I really want four AE OB15's. However, AE seems to be experiencing production issues right now with a recent supply deal that went badly and also a big TD group buy so I may have to wait a while  I'm contacting FI to see if they will build an OB-friendly pair of IB318's and I will replace one of my Z660s for a Behringer EP2500. A couple of OB 18's with 30mm of xmax and 700 watts each should be plenty for bass


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## chad

What makes the driver OB friendly? In other words does IB friendly=OB friendly?


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## xanderin

Infinite Baffle is a driver with a solid(infinite) wall separating the front and back waves. Open Baffle means that a finite wall separates the two, however wave interaction, still takes place.


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## chad

xanderin said:


> Infinite Baffle is a driver with a solid(infinite) wall separating the front and back waves. Open Baffle means that a finite wall separates the two, however wave interaction, still takes place.


I'm assuming most are aware of this by now, but given the wave interaction, are there any specific parameters for OB speakers that would NOT lead one to use a driver suitable for IB use. 


So yeah, no enclosure to act as suspension reinforcement, etc... but has the cult of the audiophile specified a specific parameter set?


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## 2010hummerguy

chad said:


> I'm assuming most are aware of this by now, but given the wave interaction, are there any specific parameters for OB speakers that would NOT lead one to use a driver suitable for IB use.
> 
> 
> So yeah, no enclosure to act as suspension reinforcement, etc... but has the cult of the audiophile specified a specific parameter set?


Great question, I will try to answer but my answer will be limited to regurgitation of what I have been reading over the past couple months and not based on experience or mathematic deduction.

Caveats aside, here are the list of ways to have a successful OB woofer:

1.) Low free-air resonance (FS) to "anchor" the woofer's response
2.) High Qts similar to IB
3.) Area, larger woofers/more of them are required vs. enclosed woofers.
4.) Decent Xmax, especially for a lower Qts woofer. Higher Qts is preferred but excursion allows wiggle-room with equalization.
5.) Low moving mass (mms) to cut down on baffle movement/vibration

I'll be sure to add more as I learn them.


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## chad

chad said:


> \
> 
> Almost wondering if finding a second hand DCX2496 may be an option, rumor has it 200 bucks can be an attainable number.


BTW, Rumor has it that it arrived at my front door yesterday... 200 bucks


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## drtool

Great thread I am in like flint. Chad don't you dare.


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## 2010hummerguy

Okay, picked up two pairs of Dayton IB 12's and another pair of SEAS Excel W22's, driver search is complete for now. I still REALLY want some AE OB15's but I want to wait until they have their inventory in order before sending my money to a business that may not turn a product for 6 months. I'm still looking for a preamp, most likely a Lexicon DC-1 or DC-2. My house was like National Lampoon's Christmas Vacation for the past 2 weeks so I never had a chance to put up some test baffles. Hopefully I will get around to it next weekend.


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## 2010hummerguy

Okay, been a few months and I need to provide some updates.

The Elan Z660 amps sounded HORRENDOUS but they found a good home in a local restaurant for sound reinforcement. In their place I picked up a pair of MINT Rotel RB-976 6 channel amps that sound absolutely heavenly. Paired them with a Rotel RSX-1056 receiver as the world's most expensive volume control (it is literally being used only for the multi-in/multi-out for volume control between the miniDSP and the amps).

I ended up selling the dBX crossover; after reading more and more about open baffle, I just needed to get something with far more flexibility. I purchased a miniDSP 2x8 with the miniDIGI board. This is my DAC and takes PCM 2 channel from all of my sources which is then crossed over 3 ways for the tweeters, mids and woofers.

Here's a pic of the prototype's first phase (go easy on my raw MDF baffles, the final product will likely be some sort of hardwood  ):










Parts list so far:
4x Vifa XT25
4x Magnecor WG300 waveguides
4x Seas Excel W22EX001
2x Acoustic Elegance IB15-8
miniDSP 2x8/miniDIGI
Rotel RSX-1056 for volume control (multi-in, multi-out)
2x Rotel RB-976

The tweeters are wired in series to produce an 8ohm load but the rear is out of phase to adhere to the principles of dipole theory. The Excels are wired in parallel for a 4 ohm load. The IB15's are bridged from two channels on each amp for about 150 watts a piece. John at AE recommends closer to 400 watts to accomplish full excursion so I may end up with some bigger amps to power four of these down the road. I can tell you right now that I will be happy with these at 150 watts each for some time until I move into a larger house.

I have 4 channels left just waiting to be bridged to another pair of IB15's. These woofers are no joke; straight out of the box with zero EQ they really surprised me. I probably have some room gain working for me but wow these get loud and low.

I have some work cut out for me with the mids/tweeters, setting levels correctly and whatnot. I am hoping to get REW (Room Equalizer Wizard) installed and running tomorrow night on the miniDSP to really dial things in.

Overall I am pretty excited so far. Imaging is SUPERB; the soundstage is HUGE. Bass is ample and vocals are accurate and very airy. Can't wait to spend more time with this, what a fun project this has been. Chalk up another open baffle addict, I may never go back to boxes.

Thanks for reading!


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## chad

good call on the miniDSP


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## Wesayso

Very cool! Glad it's working out for you. I couldn't get past my GF to try something like this.


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## chad

Best to break her in before GF turns into WIFE.


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## 2010hummerguy

I'm pretty lucky, my wife lets me get away with quite a bit when it comes to my hobbies/passions. Hopefully it continues


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## 2010hummerguy

New case for the miniDSP arrived yesterday. It is a Rotel RMB-1077 that had the amp modules removed, perfect!

Before removing the input stage/output stage and power supply:









All installed and in its new "home", matches the other Rotel components rather well:









Right now the back end isn't the prettiest; I'm running it with the rear panel removed and wires running directly to the miniDSP board. I'm waiting on some parts to arrive so I can utilize as much of the "stock" connections as possible on the Rotel chassis. I also want to take advantage of the power switch and power LED, should be a pretty easy project as Rotel was fairly liberal with wire leads.

I have to admit, the Vifa XT25's were a little harsh/distorted in the lower ranges for a couple weeks. Now things have improved dramatically...either I've grown used to them or there is actually some kind of break-in period on these. The huge soundstage continues to amaze me. Hoping to be in a larger house by May where I can do some serious high SPL RTA work.


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