[panomaniac]

Here's a little summary of the Open Baffle Designs at RMAF (Rocky Mountain Audio Fest) this year.

I went this year as an attendee, not an exhibitor, so the show was much more fun.  I was there with JBspeakerman and his 2 crazy OB rigs that we had in the sleeping room.  The neighbors did not like us much. =(

Below are my short reviews of the Open Baffle rigs we heard this year.
Obviously, all opinions are my subjective taste.  I tried to go to each room with a mind as open as a baffle should be -   and my opinions are based solely on the systems as presented at RMAF. None of these systems have I heard before.

1) Linkwitz Orion. 
 Big disappointment.  This is probably the most well known of the open baffle systems, so I figured it to be a benchmark. (Maybe my mind was not so open, after all)  I didn't care for it.
Though the tonal balance was pretty good, with no real rough spots, there was no life, either.  Dynamics just were not there.  It did not sound like live music, it sounded like a too well behaved, hi-fi speaker.  I did chat with Mr. Linkwitz for awhile, a charming and intelligent fellow.  He did say that his reference is not other speakers, but live music.  I found that odd, as his Orion seemed so lifeless.  Maybe we hear very differently?
JBspeakerman says he heard a set of Orions a few years back in Baltimore and they were much better.  Wonder why these weren't?

The Pluto, however (not OB) was great!  Linkwitz played just the right type of music to compliment them. Pure fun.

So the Orion under-whelmed me, just not engaging, too polite and a bit lifeless for my tastes.  Well made and well engineered, for sure, but just not very musical - it didn't draw me in.

2) Emerald Physics CS1
Here's an open baffle speaker that should really kick ass!  4x15" for the woofers, compression driver for the top, active digital crossover (Behringer DCX).  Speakers were  beautifully built, a real masterpiece.  Sadly, it failed to impress with its sound.  Again, not very dynamic (why??) and a bit lifeless.   The CS1 had more music to it than the Orion, to be sure, but not what you might think - not live.  Tonal balance was good and the frequency response seemed very flat, one of the flattest in the bumpy hotel rooms.  Imaging was better than average, but only just a  little.  But like the Orion, not much life to them.
I don't understand how they managed to squash the CS1 so much.  It certainly has all the right ingredients, but they just didn't come together into real music.  Nothing bad, but nothing really great, either. Left me wanting more. Such a pity.

3)  GR Research
Went by the room, but hardly remember them at all.  Guess they didn't impress me.  Will try to remember and post if I do.

4) Lowther + ToneTubby
A kit speaker with the Lowther PM6A doing duty above 200Hz and an Alnico 12" Tone Tubby filling in from 200Hz to 60Hz then picked up by a little Velodyne powered sub under that.
    Not bad, but not great.  Tonal balance a little light, which was odd as there was a powered box sub for the bottom.  Yet again, a rather unengaging speaker, though livelier than some others. At least it didn't feel over managed. Plenty of detail and a bit of the Lowther shout, but overall too tame for my tastes.  Imaging was unremarkable.  The speaker shown was a kit; parts cost comes to about $2750.  Not bad, but I think most of us here could do better with the same budget.  In fact the Lowther rig I heard at last year's RMAF (Nelson Pass' personal rig) was better - but I don't know the cost.

5)  NOLA  Baby Grand
Not a full open baffle, as the bass is boxed.  Excellent dynamics!  Some of the best dynamics of the show.  Nice clear midrange, good highs.  Kind of a funny speaker, it seems to get it about 1/2 right.  Dynamic and lifelike, but no imaging to speak of and you would not be convinced that a real, live voice or musical instrument was there in front of you.  But almost.   Maybe it was just the room setup.  Maybe just too many mids and tweets. =)


That's all the OBs I remember from the show.  As an OB fan, I'll have to say I was disappointed.   All the OBs there seemed to have the life sucked out of them.  They all sounded as though they had been massaged to death, massaged to make them "behave", perhaps?   Whatever was done, they seems lifeless and most didn't even image well.

Lest you think I'm a terrible audio snob who doesn't like anything, let me tell you that there were a number of speakers this year a RMAF that I really did like.  From reasonably priced to over the moon - but none of them were open baffle.  What a shame.   I've certainly heard and built better OB systems.  In fact, we had 2 in our hotel room.  More on that in the next post.

[panomaniac]

One I forgot - The Bastanis.   Another 1/2 open baffle rig.

Don't remember if it was the Apollo or the Mercury.

Nice enough, but too many rough edges in the sound for me.  I can forgive a lot of rough edges if the overall sound is engaging, but I did not find the Bastanis so.  Did not  stay in the room long, just didn't float my boat.

[Angaria]

Thanks for this very thorough summary!  Had several Nola's and would agree with you on their general signature.

[KS]

Below are my short reviews of the Open Baffle rigs we heard this year.  Obviously, all opinions are my subjective taste.  I tried to go to each room with a mind as open as a baffle should be -   and my opinions are based solely on the systems as presented at RMAF. None of these systems have I heard before.

3)  GR Research
Went by the room, but hardly remember them at all.  Guess they didn't impress me.  Will try to remember and post if I do.

I have an open baffle line source.  It has a front baffle that looks a bit like the (AV123) LS-9. It uses the same tweeters (9 of them) but in free air. It also uses twelve 6.5" woofers, but they are quite different than the woofers in the LS-9. These woofers are designed to play in free air. So that is the front baffle...

20" back from that is the rear baffle. The front and rear baffles are linked with an inner frame structure. The sides are open. The rear baffle supports six 12" woofers (all SW-12-16FR's). They are all direct servo controlled of course. So they will have a flat response to below 20Hz with absolute control and EQ system.

In the center of the structure there is a wedge shaped divider facing the front baffle to defuse the back wave and keep it from reflecting off of the rear subs.
-----------------------
Cabinets for the big open baffle line sources were ready, and then not ready, then ready... but a long way from here and time was running out. I could have made arrangements to get them here but it would have just left me with a couple of days to measure, test, design networks, build out networks, and fully assemble the speakers. It was possible but left no time for any unforeseen issues. It would also mean that they would not be burned in and in top form. That is not how I want to go to a show.

Plus, as big of an attention getter as that would have been, this new company was not ready to be producing these on a production level yet. It could be 6 months out from product delivery time. So while it would have been a lot of fun and a serious show stopper, rushing it in was not the most wise decision.

[ttan98]

Lynn Olson seemed to think otherwise, he said the overall sound quality(his kind of sound reproduction) was an improvement over the last years, not only in the OB speakers but right across all types of speakers. Those interested can go and read his comments at DIYAudio.

BTW I wasn't there, I live too far away.

[Danny Richie]

Sorry guys, but the enclosures for the big open baffle line sources just weren't ready yet. I had to fall back to using some LS-9's in that room.

We also had a very specially open baffle design to premier in my smaller room at the Marriott, but it wasn't ready yet either. We then went to plan B and showed the X-Statik's that I designed for AV123 in that room. It used an open baffle MTM upper section. It was proclaimed by many as the best value at the show. At only $799 a pair maybe it was the best value at the show.



Major magazine reviews will be out shortly.

[Bob in St. Louis]

Thanks for the review Panomaniac!

Bob

[Magnetar]

Sorry guys, but the enclosures for the big open baffle line sources just weren't ready yet. I had to fall back to using some LS-9's in that room.
At only $799 a pair maybe it was the best value at the show.



Major magazine reviews will be out shortly.

799! From the speakers I've seen posted around the web those should be $7999.00. Look great. Probably sound great too....

Will the open baffle line sources be pure dipole?

[Danny Richie]

Will the open baffle line sources be pure dipole?

Yes they will, and they will play flat to 20Hz.  aa

[dweekie]

4) Lowther + ToneTubby
A kit speaker with the Lowther PM6A doing duty above 200Hz and an Alnico 12" Tone Tubby filling in from 200Hz to 60Hz then picked up by a little Velodyne powered sub under that.
    Not bad, but not great.  Tonal balance a little light, which was odd as there was a powered box sub for the bottom.  Yet again, a rather unengaging speaker, though livelier than some others. At least it didn't feel over managed. Plenty of detail and a bit of the Lowther shout, but overall too tame for my tastes.  Imaging was unremarkable.  The speaker shown was a kit; parts cost comes to about $2750.  Not bad, but I think most of us here could do better with the same budget.  In fact the Lowther rig I heard at last year's RMAF (Nelson Pass' personal rig) was better - but I don't know the cost.

Some details I found.  It's a simple crossover.  http://www.diyaudio.com/forums/showthread.php?postid=1633968#post1633968

I believe Nelson's unit used his active crossover with different woofers, which would be quite a bit more expensive overall.  

[panomaniac]

I didn't hear or see the rig with the dog - wish I had, looks great and the price is hard to beat!

As for the Lowther rig, yes, simple x-over.  Paperwork says series x-over with 12mH across the Lowther, 52uF cap across the TT (16 ohm drivers).

Sorry I didn't see Lynn at the show.  I do agree that there was a lot more variety at this year's show.  Lot's of great stuff and less "cookie-cutter" than last year.   It was just the OB rigs that disappointed me.

[pbrstreetgang]

So you did hear some GR OBs or the LS?

[Danny Richie]

I will also note that if you looked in at our room on Sunday you would have seen that we were showing the small Tyler Acoustics mini-monitors with one of our Direct Servo subs.



We only played the X-Statik's Friday and Saturday. In fact I wasn't real happy with the sound on Friday. We didn't have the Direct Servo sub there until Saturday (Friday night) and due to the limited number of hours on the X-Statik's they sounded pretty fresh that first day. I asked for a burned in pair, but I don't think that they were. They sound fresh out of the box to me.

By Saturday they had really smoothed out and with the sub we were producing full range sound. I measured the X-Statik's and Direct Servo sub to make sure they were in phase with one another (I took my Clio system). The measurements showed them flat to 20Hz. 

[panomaniac]

As a follow up to my “Disappointed with the OB rigs I heard” post at the top, here is a little more info on what was going on at the show.  Despite the let down in what I thought should be great OB rigs, there was plenty of very good stuff at the show - both speakers and electronics.

It was fun to see so many people I know and hear so much good music and great gear.
Mr. Opnly Bafl'd  (Lin) from this forum stopped by the room a couple of times; he was just 2 doors down.  Don't know if he liked what we had in the room, but I think we at least convinced him that you can get real bass, real masculine bass - from an OB rig with a passive x-over.  =)  I'll let him chime in if he wants to.  We also had the New Orleans Crewe of the Open Baffle stop by; they seemed to have a good time.  But I think they have a good time no matter what. 

The most fun part was that JB(speakerman) had brought 2 of his homemade OB rigs with him.  You'll see them in the photo below.  The goofy looking dude is me.



There was the cheap little rig, AKA the Manzanitas, that you will see on the floor behind me.  Just a passive 2 way with a Peerless 12" sub and a Seas dome tweeter.  The system has been documented over on DiyAudio.com  Parts cost about $150 per side.
Won't play super loud, but plenty of grunt for most size listening rooms.  Images very well, too.  And for the price…  Well, to quote Lin "I've paid more in tax on a pair of speakers."   Just a project to show you don't have to spend a fortune to get great music and low, clean bass.

The big uglies I'm leaning against are the "Big Boys."  18" P.Audio coax.  Real monsters.  They will really shake the walls with only a few watts.  No power compression at all, tons of bass and clean, clean sound.  We were playing at 105 to 110dB peaks with no strain at all.  Could have gone louder, but the neighbors shut us down.
JB and I did a lot of crossover work on the rig while there. Some on the 18" woofer, but most of it on the horn.  Never did get it quite right, still some grain left on voices.  JB will work a little more x-over magic on it at home.

The cool thing about the Big Boys is that have dynamics out the wazoo.   Like real music.  And they were one of the few speakers I heard at RMAF that had real depth and width to the sound stage.  Few of the speakers at RMAF had much depth, with some notable exceptions. (Gershman, Reference Audio 3A, Focal, to name a few).

Funny thing about working on the crossover there at the show was that we would get to a point where the rig just didn't sound right, just was not living up to its potential.  We'd take a break and go listen to a lot of other stuff.  Without fail, every time we came back to the room and fired up the Big Boys I thought "Oh, wow!  These really are good."  Then it was back to work.

For most of the show we assumed we had the biggest drivers there, until late Sunday.  I just happened to walk past room 586 and look thru the open door. What did I see?  18" coax drivers in big bass reflex boxes!  Yes, the same P.Audio drivers.   Same big, live sound, same real live dynamics.   Crossover wasn't the best, but the basics were there.  JB said he could hear the box and it bothered him, I didn't notice it.  Whatever the case, that big P.Audio coax is a real winner.

My conclusion?   With a little skill and patience and not too much money, you can build an OB rig that will sound as good as or better than most of the commercial rigs out there.
So what are you waiting for? 

[Magnetar]

Will the open baffle line sources be pure dipole?

Yes they will, and they will play flat to 20Hz.  aa

Hmmm, flat - so I can get 65 cycles flat as in +-0 compared to say 100, 200, 500 cycles at around 102 db sensitivity but it took seven 93 db sensitive 10's wired in parallel to get it. Will have another line here that should do 40 BUT 20 flat???

What are you using for bass drivers? How sensitive is it? How are you measuring this?

Also what are you using for the dipole mid and treble?

[opnly bafld]

Questions:

Will the open baffle line sources be pure dipole?

Yes they will, and they will play flat to 20Hz.  aa

Hmmm, flat - so I can get 65 cycles flat as in +-0 compared to say 100, 200, 500 cycles at around 102 db sensitivity but it took seven 93 db sensitive 10's wired in parallel to get it. Will have another line here that should do 40 BUT 20 flat???

What are you using for bass drivers? How sensitive is it? How are you measuring this?

Also what are you using for the dipole mid and treble?

Answers:

I have an open baffle line source.  It has a front baffle that looks a bit like the (AV123) LS-9. It uses the same tweeters (9 of them) but in free air. It also uses twelve 6.5" woofers, but they are quite different than the woofers in the LS-9. These woofers are designed to play in free air. So that is the front baffle...

20" back from that is the rear baffle. The front and rear baffles are linked with an inner frame structure. The sides are open. The rear baffle supports six 12" woofers (all SW-12-16FR's). They are all direct servo controlled of course. So they will have a flat response to below 20Hz with absolute control and EQ system.

In the center of the structure there is a wedge shaped divider facing the front baffle to defuse the back wave and keep it from reflecting off of the rear subs.
-----------------------

[Magnetar]

Ahhh - Thanks EQ should due it with a big BUT

It's great to see someone building something like this . Having the mid and treble dipole really opens things up. I wonder about the backwave being diffused? Might work great?? Why not a separete bass panel? It would probably be easier to place for best performance.

Answers:

I have an open baffle line source.  It has a front baffle that looks a bit like the (AV123) LS-9. It uses the same tweeters (9 of them) but in free air. It also uses twelve 6.5" woofers, but they are quite different than the woofers in the LS-9. These woofers are designed to play in free air. So that is the front baffle...

20" back from that is the rear baffle. The front and rear baffles are linked with an inner frame structure. The sides are open. The rear baffle supports six 12" woofers (all SW-12-16FR's). They are all direct servo controlled of course. So they will have a flat response to below 20Hz with absolute control and EQ system.

In the center of the structure there is a wedge shaped divider facing the front baffle to defuse the back wave and keep it from reflecting off of the rear subs.
-----------------------

[/quote]

[Danny Richie]

I wonder about the backwave being diffused? Might work great??

The wedge shaped center structure that faces the front baffle is coverd with No Rez. It should defuse and absorb the back wave so that it will not reflect off of the rear baffle with all the 12" woofers.

Why not a separete bass panel? It would probably be easier to place for best performance.

A second tower would be too intrusive looking and with it behind the front baffle it is not only hidden but supports the front baffle with its frame work.

I'll post some pics in a couple of weeks when it is all finished up.

[opnly bafld]

Mostly agree with Panomaniac's brief review of OBs at RMAF, well done Sir.

As for the OBs playing down the hall,
the smaller 2 ways were amazing considering JB dreamed them up. 
In a not large room with a little extra juice they would more than hold their own me thinks.

The larger P Audio coaxials were really bad, if JB wants to get rid of them I will pay for shipping to my house. 
They can start and stop with the best of them, have huge dynamics and bass like the  "Back to the future"
guitar scene. 

Thanks MM and JB,
Lin 

[JBspeakerman]

Hey gents....

Opnly bafld... great to meet you and your Bro, thanks for stopping by.   And thanks for the positive (I think!!) support - feedback!  Fun to share the BB's with you guys....  Lets see.... there is packing... freight... and handling...  Hmmmm!  Long way back to the Midwest....

And Pano... as always... concise and professional....

Getting a design to fruition is tough... and getting it to play at or near it's potential in widely varying venues is a lot tougher!  Suspect this has a lot to do with what we heard at RMAF.   Know the Orion's for example are way better than what we were hearing... the usual suspects were at work... room mainly as well as what was playing music wise during my visits.....    The Orion does not have the following it does with out good reason and is a big motivator for me personally.  As Pano stated in his post above.. I have heard them before in a home and was quite impressed!!   But it just did not come close to it's potential (IMHO) in Denver.  Still one hell of a design achievement!!

The Pluto was way cool... lower bar to be sure... but that little S*** really impressed me!

What was of interest to me was the kind of front end money I saw at RMAF... as in amps and Dacs oh my.  Not unusual to see $10K-$100K of equipment ... cables as part of so many systems...

Who has that kind of money?... know every room wanted to put their best foot forward... but Geezzzzz... One thing I do is use stuff up front most of us mere mortals can afford... heck... justify.   If you get the speaker right... it sure makes things way more affordable.   

Some of the items speaker wise that impressed me included the Seas 8" full range in a small sealed tower at Madisound.... a nice Dyna-Audio two way.... YG Acoustics... Yokohama Baysidenet Magnetic suspension full range horn... (far out large Vase shaped enclosure) Gershman .... The Bastanis OB... Merlin VSM and bang for the buck electronics from Grant Audio.

There were of coarse many other outstanding rooms... items presented... so much to hear... so little time...

Will check my notes and literature collect further and if I have left anything out I will post same later.

JB