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Old 18th November 2007, 05:35 PM   #51
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Default Modifying orions

Hi Grey,

me, for instance. I own a pair of Orions and I am just about to reproduce the XOs in the digital domain (oh, how shocking, my dear).

I would be very keen on comparing the original, the digital, and the "passed" XOs. Unfortunately, too stupid to do the latter on my own.

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Old 18th November 2007, 05:50 PM   #52
Davey is offline Davey  United States
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I think "the line" with SL is very clear. And he notes this in the "caution" at the bottom of his front page.

Any of the design modifications being discussed here would cause the Orion to cease being an SL's view.
However, I think he enjoys/welcomes new thinking on any of his efforts. But you better have your A-game ready if you find yourself in a discussion with him about it.

SL does not participate in most discussion forums....which I guess kind of makes him an easy target, but you might find him at the OUG from time to time.

Here's an example of recent "modification" to one of his designs and the discussion that ensued.


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Old 18th November 2007, 06:19 PM   #53
paulb is offline paulb  Canada
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I'm interested in the Orion because I am getting ready for a speaker upgrade, and it seems like a good choice: It seems to be a credible, accepted design. Lacking carpentry ability (and inclination), I need something simple that I can talk somebody into helping me build. I like the idea of the open baffle. And finally, I am a firm believer that biamping/triamping is the way to go, and there aren't very many DIY designs out there employing it.
My interest in this thread is because I would like to use a different version of the electronics for the Orion. Also, I need an excuse to keep building amps. I'm not particularly interested in just stuffing the Linkwitz board and knocking off a few gainclones. I would like to see it with simpler but high-end DIY electronics. I may end up using a DSP-based system to tinker around with it a bit, but in the meantime it would be nice to build something where I am reasonably confident of the results.
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Old 18th November 2007, 07:22 PM   #54
Pasi P is offline Pasi P  Finland
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Hi all,

I think it is ok, if anybody tries to improve Orion desing.

But. Anybody who is saying Orion is from stone age etc. should first "sit back and listen" properly built Orions with electronics Linkwitz recommends.

If one is not like what he hear, then it is OK to say what he think is reason to bad sound.

OP amps could be bad somewhere in poorly designed system, but Orion loves op-amps IMHO
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Old 18th November 2007, 07:41 PM   #55
Variac is offline Variac  Costa Rica
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If, for instance, someone were to take my earlier suggestion and use a physical offset to time align the drivers rather than do it electronically, would that still be an Orion?
If the intent is to re-imagine Linkwitz's speaker, it would be useful to set some ground rules as to what does and does not constitute fair play. I suppose it's clear that I'd go back nearly to square one, others seem to feel that a simple opamp swap is the limit.
First, I'm pretty sure that offsetting the drivers is something that would occur to Linkwitz and he rejected that. As I pointed out, he had a manufacturer making his (quite expensive) speakers in the past- he isn't some guy that just made some speakers for himself in his living room. I don't think that he would be concerned with their possible lack of woodworking skills!

Offsetting the drivers is like just about everything, a compromise, as if you offset the drivers you can end up with baffle diffraction problems, if you slope the baffle, then the response changes depending on how close you sit, etc. So I think that that choice is a fundamental SL choice and shouldn't be tampered with.

I think that the scope of the project is pretty clear:

This project is to leave the Orion panel and drivers alone, and confine any modifications to the circuitry. This would involve substituting discrete opamps for chip opamps, and combining circuits
as is possible to avoid redundancy and eliminate maybe half the opamps. Of course something like leaving off the high filter would be something that could also be easily explored...

With this definition, the project could be useful to any of the owners of an Orion, and actually encourage more people to build them, which I assume would make Siegfried Linkwitz more interested.
Also it would allow an easy comparison between the stock crossovers, and the new crossovers, which is one of the major appeals of this proposed project

Unfortunately , this combining of circuits involves "The Art of Electronics" to coin a phrease , and will require someone of a certain level of expertise....

Also, It appears that the only way to get the current exact circuit is to have a set of his boards, which some people here have. I believe that he sells unpopulated boards. Perhaps someone with the boards can compare them to the circuit I linked to. Is it true that there isn't an exact schematic of the current circuitry
"The geek shall inherit the earth"
Burning Amp thread here on diyAudio
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Old 18th November 2007, 08:02 PM   #56
Variac is offline Variac  Costa Rica
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the name should have ASP in it as that is what we are replacing it we agree to only focus on the "black box" Aurion is a little too close sounding to Orion so I think that might cause confusion. Nice of Linkwitz to offer a final tribute to the disappearing planet Pluto...

How about something like the "Mercury ASP" or as Homer S. would like: "Uranus ASP"
"The geek shall inherit the earth"
Burning Amp thread here on diyAudio
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Old 18th November 2007, 08:53 PM   #57
S.A.G. is offline S.A.G.  Italy
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Orion ASP boards and documentation are available, but a bit pricey:

Unpopulated boards are also available for 1/3 the price of the Orion set of documentation:

A complete Orion ASP block diagram with design specs is available at:

SL provides all the design formulas for each stage of the ASP on his site:

A simple way to reduce the transistor count of the Orion ASP is to replace all the buffer stages built around the OP2134 with a discrete buffer stage. An interesting topology could be the one used by Borbely in his low cost starter kits:

A complementary cascoded JFET buffer using only 8 semiconductors.

A more radical approach to sallen and key filter replacement is described in:

I hope this help. I'm looking forward to Nelson's thoughts on this subject.


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Old 18th November 2007, 09:31 PM   #58
eLarson is offline eLarson  United States
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Default the name game

So Orion was the lover of Artemis. She also killed him. (oops.)

Scorpio was what Orion was chasing after that led to him being shot by Artemis.

Apollo was the one who sent Orion on the trail of the scorpion, and also the one that shined the beam of light on Orion far away at sea. And he was the one that challenged Artemis to hit the little spot of light with one of her arrows.

The Apollo ASP? The Artemis ASP?

Of course then there are the various stars in Orion--most famously Betelgeuse, but also Bellatrix, Rigel and Saiph; Mintaka, Almintaka and Anilam make up the belt. (It's been some years since Astronomy class, my apologies for any misspellings.)

Would a woodchuck bother to chuck MDF?
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Old 18th November 2007, 11:00 PM   #59
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I saw a SF film from 1978 called "Capricorn One" last night. A bit like Apollo 13 meets All the presidentís men. Not a bad film. I see Its Title ( minus the nefarious subplot ) as a Procrustean fit: a (science) project diverted from itís intended aim and itís also a star constellation.

So... Capricorn ASP?
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Old 18th November 2007, 11:31 PM   #60
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Originally posted by Variac

Offsetting the drivers is like just about everything, a compromise, as if you offset the drivers you can end up with baffle diffraction problems...

This is why they invented felt and foam. Felt is better over the long haul. The problem with most speakers is that they cheap out and use too little thickness. It takes something on the order of a quarter wavelength thickness to achieve decent attenuation. Time, time, and again, I see felt that is, at most, a sixteenth of an eighth of an inch thick at best. Yeah, right, to try again?
As for offsetting the baffle occurring to him--don't bet on it. If he thinks that an electronic solution is satisfactory, then it may never have crossed his mind. If there's one thing I've learned over the years, it's that if someone already has a solution in mind, they are resistant to trying any other possibility that may come up. You see it everywhere, Washington D.C., the Middle East, at work, in marriages, you name it.
You can't have it both ways, either the guy is a genius at which case it's a big duh that he's going to approach this as a filtering problem that has an electronic solution as opposed to a mechanical one, or he's which case the whole crossover is open to redesign (and possibly even the mechanical design of the speaker itself). So which is it? Make your choice and place your bets, folks.
The blind assumption that someone has evaluated all the options and chosen the best is antithetical to the basic philosophy of DIY.
If the idea is to keep everything as similar to the original Orion as possible, then you're limited to two options: Try different chip opamps or build discrete opamps.
There. Project planning done. Gentlemen, start your soldering irons.

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