Orion++ is born

[Ludvig]

If you want to "see" a really happy man, point your browser to linkwitzlab.com. Orion++ is born. :W

[ThomasW]

http://linkwitzlab.com/orion++.htm

[joecarrow]

Interesting... I noticed the other night that linkwitzlab.com was down due to bandwidth usage. This kind of compares to John Kreskovsky's NaO speaker, with the switchable rear tweeter.

Now, I get the single "+", with the rear tweeter- what's going to give us the second "+"? I can't wait to find out!

[Bill Sledge]

Joe, you beat me to it. I have heard the NaO at John's house when I lived in CT. I loved it and plan to build it when I have time!

Bill

[digital desire]

Isn't this a play right out of the bose handbook? (As far as the rear pointed tweeter?)
Raw Acoustics is doing it also.

[cjd]

Well, Bose didn't invent rear pointed tweeters...

In fact, do they even USE tweeters very much?

C

[JohnL]

I do think there is something to having the highs running in dipole. I'm the anachronist using an AMT on top of my dipole. As cool as the AMT is, I don't think it's the transducer technology that makes it sound so good, I think it's that fact that the tweeter is dipolar. When I've used domes or standard monopole ribbons or planars, they just don't have that same magic sound.

[JorgenMan]

Now, I get the single "+", with the rear tweeter- what's going to give us the second "+"? I can't wait to find out!

The second "+" is just the Thor subwoofers he has running with the Orions.

[Dennis H]

Now he needs to put front and rear waveguides on the tweeters to really match the power response of the dipole mids. Front/back waveguide Isiris anyone?

[JonMarsh]

I'll leave that innovation to some other hardy soul... :B

I've got my hands full as it is just figuring out the FRONT mounted waveguide and driver!

[tktran]

The rear tweeter sounds interesting, but it's all starting to really add up in cost. Hopefully it won't require an additional two channels of amplification?

The Orion+ is a previous mod that added a pair of Thor subwoofers and raised the 12" to 10" XLS crossover frequency to 50Hz. So now we the Orion's FOUR 10" XLS woofers in the H-frame only operating between 50Hz to 120Hz.

That's just over a single octave, by those FOUR 10" woofers + 2/4 channels of amplification. Seems to me like such a waste of resources.

Now we're going to add a pair of surface mounted tweeters, at US$170 a pop.

[jkrutke]

You know, rear firing tweeters on a dipole is one way of increasing the ambient reflected soundfield, but there's something else I've been mulling over in my mind.

Consider the value of a LR2 crossover at a higher frequency than what Linkwitz has to use with the W22. A steep crossover at a low frequency makes for a sudden transition from dipole radiation to monopole.

With a shallower crossover at a higher frequency, (using a paper cone obviously) There's more rear output at the top end of the woofer with a smoother transition to monopole. Woofers with small magnets and cleaner rear radiation would seem to be optimal for the situation. Seas Excel M15CH-002 5" Nextel with the hex magnet maybe?

[Davey]

John,

SL has already considered that possibility....and he hasn't discounted it. Possibly a MMT configuration with the lower M inverted.
The trouble is.....is that it would be a completely new speaker and not retro-fit-able to the Orion design.

I know he's fairly happy with the W22 driver and panel arrangement and considers that the strongest point of the design.

(I think he's cogitating on some other ideas as well, but hasn't shared them with me.)

Cheers,

Davey.

[AJINFLA]

Now he needs to put front and rear waveguides on the tweeters to really match the power response of the dipole mids. Front/back waveguide Isiris anyone?

Hmm, the XO would still have to be really low on the rear tweeter due to the low pass of the motor (or the cabinet in this monstrosity from many moons ago, rear driver separate amp & eq driven, variable output relative to front) for near perfect symmetry.

But a small enclosed out of phase coax could maintain pattern control and go below 1k with ease...hmm, got me thinking again Dennis. Dangerous stuff

The 1812's were going to have front/rear tweeters above 16k already, but may have to experiment a bit again with rear response/power shaping in totality. Does it ever end LOL?

cheers,

AJ

[Mazeroth]

I have corrected the master! :B

At the bottom, under Rear Tweeter Mounting, Linkwitz states this:

"The rear tweeter is wired in parallel with the front tweeter, plus to minus and minus to plus."

Ummm...isn't that series wiring?

This new Orion does sound somewhat gimmicky to me, but I'd love to hear the difference. I may experiment with this and the test dipoles I have. Good thing I bought an extra pair of RS28s when they were on sale :T

[Paul Ebert]

You know, rear firing tweeters on a dipole is one way of increasing the ambient reflected soundfield, but there's something else I've been mulling over in my mind.

Consider the value of a LR2 crossover at a higher frequency than what Linkwitz has to use with the W22. A steep crossover at a low frequency makes for a sudden transition from dipole radiation to monopole.

With a shallower crossover at a higher frequency, (using a paper cone obviously) There's more rear output at the top end of the woofer with a smoother transition to monopole. Woofers with small magnets and cleaner rear radiation would seem to be optimal for the situation. Seas Excel M15CH-002 5" Nextel with the hex magnet maybe?

Or, for a cheaper alternative, the AA6.5. That is, if it ever becomes available again...

[Doug Lockwood]

With a shallower crossover at a higher frequency, (using a paper cone obviously) There's more rear output at the top end of the woofer with a smoother transition to monopole. Woofers with small magnets and cleaner rear radiation would seem to be optimal for the situation. Seas Excel M15CH-002 5" Nextel with the hex magnet maybe?

The problem with a M15CH-002 is it pushes the Woofer to Midrange crossover up to 300 Hz or more. That stretches the H baffle resonances to their limit.
It will be interesting what SL comes up with.

Doug

[Dennis H]

But a small enclosed out of phase coax could maintain pattern control and go below 1k with ease

Yeah, I was thinking the same thing, A.J. You could even use a pair of 'bigger' coaxes, wired out of phase in a small box. The depth of the box would contribute to D and it might be good down to 400 or wherever the natural dipole rolloff started. Too bad the Seas 7" coaxes aren't really up to scratch; something like that would be perfect.

[kgveteran]

Well, Bose didn't invent rear pointed tweeters...

In fact, do they even USE tweeters very much?

C

I think they use Mweeters (midrange-tweeters)

[Davey]

"The rear tweeter is wired in parallel with the front tweeter, plus to minus and minus to plus."

Ummm...isn't that series wiring?

No. Parallel wired but inverted in polarity with respect to the front tweeter. (Front tweeter dome moves outward, rear tweeter dome moves inward.)

Davey.

[BobEllis]

I have corrected the master! :B

At the bottom, under Rear Tweeter Mounting, Linkwitz states this:

"The rear tweeter is wired in parallel with the front tweeter, plus to minus and minus to plus."

Ummm...isn't that series wiring?

Not series, but parallel with the rear tweeter connected opposite polarity. As mounted both tweeters move in the same direction.

[Rick Craig]

Joe, you beat me to it. I have heard the NaO at John's house when I lived in CT. I loved it and plan to build it when I have time!

Bill

I had a chance to hear an earlier version at the Iowa DIY event. The depth of soundstage was impressive!

[Rick Craig]

I found his comparison of the various design formats interesting. I recently had a chance to hear the Dali Megalines driven with a DSP crossover and tri-amped with subwoofers. This is a tall array and at 7-8 ft. away the phantom image was very real - quite unlike what Mr. Linkwitz noted.

[Chris7]

One question Linkwitz doesn't address (I don't think so anyway, though I may need to re-read) is whether the listener perceives the sound balance to be brighter, given that there is 3 dB more high frequency acoustic energy in the room. He mentions that "F and R add on a power basis and increase the perceived volume level." Is this a psychoacoustic increase of the overall volume level, or is it an increase in the volume level of just the highs?

I guess my question boils down to: even though the sound power sums at the listener, does the ear somehow filter out decorrelated reflections when presenting the brain with the tonal balance of the speaker? If so, why do conventional speakers in "live" rooms tend to sound brighter? I'm not entirely convinced that the effect Linkwitz is hearing couldn't be substantially simulated with equalization of the standard monopole tweeter Orions.

[capslock]

The Adire DDR (flat baffle dipole with 2x Extremis and 1x Neo3-PDR minus the back cup) received rave reviews from various people who listened them, and I have yet to hear a reserved opinion about them. Maybe this is the same phenomenon?

[Andy_G]

Everyone who hears the "Blackwood" speakers I built goes into raptures about how good they are to listen to.
They also are open back MTM+vented W

http://users.tpg.com.au/users/gradds/ARGOS/blackwood.html

They don't use anything exceptional in the way of drivers, but they have a certain yummyness about the sound quality that I have never heard from boxed mids.

Anyone thinking of building more speakers ought to seriously consider this approach. Gees if its good enough for SL and JK, etc, there has to be something going for it. :T

[JoshK]

Wouldn't a dome mid, like the new RS dome work well? You could put a first order low pass on it up high and let the power response drop gradually. It could also play low and even compensate for some of the W22's rear masking.

[fcserei]

"ORION+ transports me to the performance venue. I must close my eyes so that I do not get distracted by the glaring visual incongruence between the speakers and room in front of me and the visual acoustic space before me in my mind's eye. It seems so real and in 3D."

Anybody who claims this about 2 chanel stereo reproduction in very dissimilar acoustic space from the original recording venue needs a strong reality check.

[Paul W]

Neo 8 + Neo 3, both full dipole, might work well.

[JonMarsh]

"ORION+ transports me to the performance venue. I must close my eyes so that I do not get distracted by the glaring visual incongruence between the speakers and room in front of me and the visual acoustic space before me in my mind's eye. It seems so real and in 3D."

Anybody who claims this about 2 chanel stereo reproduction in very dissimilar acoustic space from the original recording venue needs a strong reality check.

Have you listened to an Orion at any length? Under what conditions?


I have even had this experience with the right room setup with non-dipole speakers, as early as the late 70's, so I know what he's talking about subjectively. Evn more so with the dipole style speakers I had or had access to (Magneplanars, Levinson HQD setup).

Having heard Orions under decent contitions, and having heard a lot of what was available at CES2006 in the high end exhibition at Alexis Park, I have no point to pick or disagree with Sigfried. And that is with two channel. As almost any reviewer that has listened to the Orions, (Audio Critic, Sensible Sound), they're in a class by themselves compared to nearly all commercially available speakers regardless of price.

Personally, I think SL's room is too live for the utmost in reproduction of the acoustic space on the recording, but it only illustrates how well they work in less than ideal conditions.

I'd respectively suggest checking your preconceptions at the door.

[JonMarsh]

The Adire DDR (flat baffle dipole with 2x Extremis and 1x Neo3-PDR minus the back cup) received rave reviews from various people who listened them, and I have yet to hear a reserved opinion about them. Maybe this is the same phenomenon?

Most likely, though I bet even with the back cup, the response would be similar.

[cjd]

Neo 8 + Neo 3, both full dipole, might work well.

SHHH

don't steal my, um... vague lame attempts at causing great rumbling in the sky (aka thunder)

In fact, I'm even pondering some waveguide type experiments. Which could be both front and back.

Anyone want to lend me a guiltless conscience so I can just up and order all the crap I want to play with?

My wife commented last night about how nice she is to let me build "crazy speakers" and I said "I haven't built any crazy speakers... yet" and she just said "I know" - :B

C

[JonMarsh]

SHHH

don't steal my, um... vague lame attempts at causing great rumbling in the sky (aka thunder)

In fact, I'm even pondering some waveguide type experiments. Which could be both front and back.

Anyone want to lend me a guiltless conscience so I can just up and order all the crap I want to play with?

My wife commented last night about how nice she is to let me build "crazy speakers" and I said "I haven't built any crazy speakers... yet" and she just said "I know" - :B

C

She's a gem- you treat her right, Chris!

[dawaro]

The Adire DDR (flat baffle dipole with 2x Extremis and 1x Neo3-PDR minus the back cup) received rave reviews from various people who listened them, and I have yet to hear a reserved opinion about them. Maybe this is the same phenomenon?

Being that I have most of the components to build a set of these (short the neo's and a couple of inductors) I may try to through a set together and give it a listen.

[cjd]

She's a gem- you treat her right, Chris!

It's never easy, but I do try. It helps that she has her own hobby now (finally!) - knitting. I just have to actually finish those projects I'd promised her (a needle box and a tall-thin drawer chest to store yarn)

Need better shop tools. Bandsaw, drill-press... and space

C

[AJINFLA]

I think what should be noted is the distance from the rear wall. In SL's case its close to 6'. If you're going to go full spectrum dipole, you better have some room. Another thing I noted from back with my rear driver experiments is that there was a tendency for it to add a terrific sense of realism with large scale ochestra, acoustic jazz, etc.
However with certain types of electronic music, the effect was less than desirable, though not outright unlistenable. Which is precisely why the rear driver was seperately powered, eq'd and remote volume controlled. With an off button.
That said, I may have to measure the rear output of a DA175 (thanks again PMazz) to see what the lo-pass effect of the motor/basket looks like.
The idea of reverse mount MMT, even with neo motor M's, appeals to me only if the tweeter can go way low, like the Aura NSW2, which I also happen to have a pair of . 2 Auras back to back with sufficient absorbtion between for that 1/4 wave resonance should still be relatively shallow. XO of about 6-700hz or so should keep the drivers in the omni range for near full dipole cancellation across a wide bandwidth.
Sensitivities are reasonably close for you passive guys who don't have a DCX in the toolshed LOL. Reasonable amp load & cheap too.
Might have to cut some wood this weekend. No waveguides needed 8O .

cheers,

AJ

[fjhuerta]

Hmm... what if... open baffle, two Peerless 830884 two RS125 on front, one 27TBFC on front, one rear firing 27TBFC...

Linkwitz is truly an inspiration.

[Dennis H]

One question Linkwitz doesn't address (I don't think so anyway, though I may need to re-read) is whether the listener perceives the sound balance to be brighter, given that there is 3 dB more high frequency acoustic energy in the room. He mentions that "F and R add on a power basis and increase the perceived volume level." Is this a psychoacoustic increase of the overall volume level, or is it an increase in the volume level of just the highs?

I guess my question boils down to: even though the sound power sums at the listener, does the ear somehow filter out decorrelated reflections when presenting the brain with the tonal balance of the speaker? If so, why do conventional speakers in "live" rooms tend to sound brighter? I'm not entirely convinced that the effect Linkwitz is hearing couldn't be substantially simulated with equalization of the standard monopole tweeter Orions.

SL said he only needed to turn down the dual tweeter volume in the active XO about 1 dB below the single tweeter level for it to sound 'right.' He says he tried EQ with a single tweeter but couldn't get the same effect. The point he's making is the reverberant field should have a similar frequency response to the direct sound for it to sound right. Cranking up a single tweeter to get more reverberant treble would make the direct sound too bright.

[Mark Seaton]

I'll leave that innovation to some other hardy soul... :B

I've got my hands full as it is just figuring out the FRONT mounted waveguide and driver!

Hi Jon,

Personally I see Sigfried's findings to further emphasize how critical the power and total radiation pattern of the speaker is.

Rather than trying to make a dipole with horns, I would suggest heading the other direction. Make the rest of the range better match that of a well behaved, CD-ish horn. There are both cardioid and hyper cardioid options to consider using everything from U baffles to multiple sealed drivers to multiple dipoles. The delay for a rear driver is but a filter away even in a passive design.

In my mind a design with a horn tweeter, and 2-4 mids (1-2 above, 1-2 below) operating to deliver a consistent pattern could be quite something for use in less friendly acoustic environments. One of the guys who built a Lambda Unity did this for the bass section and raved about the results.

Just some food for thought. There are only so many designs I have time to play with, so it's always interesting to see what others are finding on different paths. Besides, cardioids and dipoles don't work too well put in a baffle wall for a home theater. :roll:

[Andy_G]

SL said he only needed to turn down the dual tweeter volume in the active XO about 1 dB below the single tweeter level for it to sound 'right.' He says he tried EQ with a single tweeter but couldn't get the same effect. The point he's making is the reverberant field should have a similar frequency response to the direct sound for it to sound right. Cranking up a single tweeter to get more reverberant treble would make the direct sound too bright.

Be a bit careful with this. Iirc, SL has about 9ft behind his speakers, and sits about the same distance in front, so the rear tweeter is firing around 3 times the distance. I haven't done the maths, but I suspect we are still within the Haas effect boundary, but by the time the rear sound reachs you it will be down quite a bit from the original level.

I suspect that the distance behind the speaker will determine the amount of reduction required and change the balance required between the 2 tweeters.

[Mazeroth]

You guys are audio gurus compared to me so bear with me on this question. One thing I don't *think* was mentioned was about the delay involved with the rear firing tweeter. Would this have to be compensated for, or does the delayed tweeter add some sort of "realism" to the sound SL says is so great?

[Andy_G]

You guys are audio gurus compared to me so bear with me on this question. One thing I don't *think* was mentioned was about the delay involved with the rear firing tweeter. Would this have to be compensated for, or does the delayed tweeter add some sort of "realism" to the sound SL says is so great?

This is what I referred to above as the Haas Effect. If the delayed sound reaches you within a certain time your ears effectively treat it as one with the original. This gives a sortof "broadening" of the original sound.
What you have to remember here is that there will not be just one rear reflection, but many , that may have bounced off 1, 2 or even 3 walls.

What we are creating is, in effect, a mini-reverb.
I personally think this takes us out of the objective , into the subjective. :T

[Chris7]

SL said he only needed to turn down the dual tweeter volume in the active XO about 1 dB below the single tweeter level for it to sound 'right.' He says he tried EQ with a single tweeter but couldn't get the same effect. The point he's making is the reverberant field should have a similar frequency response to the direct sound for it to sound right. Cranking up a single tweeter to get more reverberant treble would make the direct sound too bright.

I don't think it's clear from Linkwitz' write-up whether he actually did the experiment with EQing a monopole, or whether he just doesn't believe the same effect is possible. I think the latter is probably more likely; he just seems to dismiss the possibility without necessarily having tested it: "It is not possible to obtain the same effect from playing with the frequency response of a forward firing tweeter, though I have often observed that really wide tweeter dispersion reduces harshness and sounds more realistic."

Also, Linkwitz does adjust the tweeter level, but it's not clear that the stock Orion tweeter adjustment would exactly counteract the effect of the firing rear tweeter on the total sound at the listener's position. Could what Linkwitz be hearing be partially accounted for by a lumpier response (ie. linear distortion)?

There are a lot of questions here that deserve further study.

[Dennis H]

he just seems to dismiss the possibility without necessarily having tested it:

If you know anything about SL, he tests everything. He's a fanatic about not making claims he can't back up. If you read Don Barringer's remarks in the Orion forum, much more has gone into the design than what's apparent from what SL has published so far. And he's not done yet.