Jump to content

Open Baffle Design....Very early doors!


Recommended Posts

HI All,

 

Possibly looking into playing around with some 15" & 12" drivers in an open baffle design to hopefully build some speakers.

 

I know very little about speaker design, even less so about crossover design but I enjoy the learning process & will have a good mate who hopefully knows more than me so lets just see whee this takes us.

 

I could end up just buying some Spatial's or PureAudioProject or speakers made by Walter Liederman (Emerald Physics).

 

https://www.spatialaudio.us/

https://www.pureaudioproject.com/

https://www.underwoodhifi.com/products/ep24

 

What I understand in regards one of the fatal floors of open baffle speakers is Phase Cancellation whereby essentially what's coming out the front is cancelled by what coming out the back but from my basic understanding which is from a YouTube video of Clayton Shaw discussing OB design (see below). 

 

What Clayton from Spatial was saying is by using dipolar LF drivers, this helps to eliminate front to back phase cancellation...I think he then went onto describe how baffle design can actually use phase cancellation at the sides of the speakers which helps to reduce 1st reflection points from the walls & ceiling.

 

It's a long video, Clayton discusses & illustrates Cabinets Vs OB from about the 20 min mark.

 

 

So, to start this project I'm on the hunt for suitable for OB design 15" Dipolar woofers.

 

I think we have a full range 12" that should work for Mids & HF's but keen for anyone who has ploughed this field before to offer any advice.

 

Cheers all

Matt

 

Link to post
Share on other sites
  • Replies 105
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Popular Posts

Hi All,   I trust everyone had a great Christmas? Mine was a little scary as my Dad had a turn which required a trip to hospital & a pacemaker implanted 24 hours later but he's all goo n

Hi all,   Thanks for all your posts, so much to learn.   Here are some pictures from today’s efforts.           Will build the

I've recently built my first open baffle project being the "lionidas" using W15 woofer and Fast 8 (wide band) drivers. In my room they measure to 30Hz before dropping off which is quite the feat for a

Definition of a Dipole Speaker.

 

A dipole speaker enclosure in its simplest form is constructed by mounting a loudspeaker driver on a flat panel. The panel may be folded to conserve space.

 

The term dipole derives from the fact that the polar response consists of two lobes, with equal radiation forwards and backwards, and none perpendicular to the axis. By comparison a monopole response consists of one lobe. This can be useful in reducing the stimulation of resonant room modes at low frequencies. It also results in high frequencies being reflected from any rear wall, which can enhance the naturalness of the sound in typical listening rooms by creating more diffuse reverberation, though in theory it could detract from stereo localization. For this reason dipole speakers are often used as surround channel speakers, where a diffuse sound is desired to create ambience. (Wiki)

 

Ok....so the challenge is to achieve front to back directional bass!

Link to post
Share on other sites

Have a look at real open baffle like the early Klangfilm, they need to be v wide to minimise cancellation and to achieve bass.

Quite a bit of ‘justification’ fr Spatial guys of deficiencies of their design 

Link to post
Share on other sites

Hi Matt,

 

We crossed paths at a Classic Album Sunday at the Jade some time ago now.

 

I have had Hawthorne Audio open baffles for about the last 10 years and enjoyed them immensely.

Started with Performance Silver Iris and moved to Sterling Silver Iris, with two 15" bass augmentation drivers (Augies) per baffle. So, I have 6 15" drivers looking at me?

 

I am in the process of moving to Red Spade PSE horns and bass bins, which I hope will be completed early next year, with Paul Spencer coming over to dial them in for me.

I will have various OB items spare after that if you want to play around or that you could listen to if you wish. PM me perhaps if you want to discuss anything along those lines. 

 

Another member here, "gremrock" is also currently building another OB using some Hawthorne Audio AMT's that I passed on to him.

 

You really need to hear them to know what they bring to the table, and I can assure you, it is not anaemic bass, as many seem to think?

 

Cheers, Jim

  • Like 1
Link to post
Share on other sites

Hi Jim,

 

Nice to hear from you, hopefully early next year we will be organizing more CAS GTG's at the Jade.

 

I did find Gremrock's post & I'm following but he's not posted for a while.

 

 

I'm keen to have a listen as I've not actually heard OB speakers, just been reading about their sound & thinking they could suit me.....even as a pair of 2nd speakers. I'm also thinking that they wouldn't have to cost the earth & could be easier to home DIY....I could be wrong!

 

I'm also working closely with @Grizzly on this as he has access to some nice full range drivers that could work quite well in an OB design.

 

Let me know when would suit & I'll speak to Ant & maybe we can both come down.

 

Cheers

Matt

 

 

Link to post
Share on other sites
On 02/12/2020 at 12:26 AM, crankit said:

Another option is from GR Research they have a few OB options in kit form

 

 

 

 Thanks..I did see this website a while back but forgot about it.

 

They don't seem to have much stock at the moment & I'm struggling to find any 15" drivers, just "servo" woofers with amp?

 

Cheers

Matt

Link to post
Share on other sites

Am in the "figuring out what to do" phase and firmly subscribed to this thread and on a similar path. Understand that OB and horn designs like the red spade bring different things to the table. Would be interested to hear from people that have gone from one to the other and the things that each bring to the table and the drawbacks. or if there is a thread that already does this please point me to it. 

Link to post
Share on other sites

I have been looking also and have the PCB's for the 6 mono amps, power supplies, soft start, speaker protection etc already.  I have the Wild Burro Betsy for mids and GR Reasearch NEO3 for tweeter.

 

For lows I have been looking at the SB Audience Bianco-15OB350.

 

https://www.wagneronline.com.au/sb-audience-bianco-15-open-baffle-woofer-350w/sb-audience-range/sb-acoustics/speaker-drivers/audio-speakers-pa/bianco-150b350-89897/1002168/pd/

 

But, I'm stuck at the point of determining if the 15" will give enough bass without large equalisation boost and considering adding the SB Audience-18SW500.  The problem is if I go 18", 15" then the 8" Betsy that the centre of the Betsy is above ear height.

 

I am avoiding passive crossover design by using a Intel Nuc to do the filters feeding a 8 channel DAC (leaving a pair of channels in case a Sub is warranted).

 

The Betsy wont be the best driver, but, will be a good start to see how the rest of the speaker goes :-)

Link to post
Share on other sites

Shallow open back cabinets allow decent bass response from the full range and woofer. A similar result to a far wider baffle with the benefit of being able to baby/pet proof by adding speaker cloth to the back of the cabinet.

 

This is my system a few days ago.... Shallow open back cabinet with fullrange, woofer, front facing ribbons tweeter and ceiling facing bullet compression tweeter.

 

https://drive.google.com/file/d/1ZXGv6xmE4E0smCZsuLEP0bBQG5KAjg-C/view?usp=sharing

 

These cabinets are very heavy, being made of Karri hardwood. Mass helps damp vibration. Likewise I have Dynamat Extreme damping the top and bottom of the cabinet. I may add to the sides at some point also though I doubt there will be any noticeable difference.

Edited by MattyW
  • Like 1
Link to post
Share on other sites
On 01/12/2020 at 11:48 PM, mattjtaylor2809 said:

 

On 02/12/2020 at 12:07 AM, denimhunter said:

Have a look at real open baffle like the early Klangfilm, they need to be v wide to minimise cancellation and to achieve bass.

Quite a bit of ‘justification’ fr Spatial guys of deficiencies of their design 

The reason why Martin was able to achieve so much with an Eminence Alpha 15A and an FE103 is that he matched them pretty well. The 15A, with a Qts over 1.0 and a reasonably high efficiency (10dB more than the FE103) could provide reasonable extension down to 50Hz on a very small panel (relatively). Along with a well designed crossover and a suitable fullrange speaker, this achieved a balanced output. It didn't get very loud, but it did sound good - certainly for the price.

His Lowther PM2C/AE OB15 speakers certainly look the business and seem to measure up (and Martin certainly likes the sound).

I have 4 drivers that use the same motor design used in the AE drivers. Nick McKinney (R.I.P.) designed this motor and produced a few drivers as Lambda - but he was never a business man. His design was bought by the guy who now runs AE and all the drivers use a version of this. The Apollo upgrade (if they still do this) is certainly worth the money if you intend to push the drivers at all. I've never heard of one breaking, and I seen some of them in some pretty interesting designs (Kyron Audio Gaia is my favourite).

  • Haha 1
Link to post
Share on other sites
6 minutes ago, Cloth Ears said:

 

The reason why Martin was able to achieve so much with an Eminence Alpha 15A and an FE103 is that he matched them pretty well. The 15A, with a Qts over 1.0 and a reasonably high efficiency (10dB more than the FE103) could provide reasonable extension down to 50Hz on a very small panel (relatively). Along with a well designed crossover and a suitable fullrange speaker, this achieved a balanced output. It didn't get very loud, but it did sound good - certainly for the price.

His Lowther PM2C/AE OB15 speakers certainly look the business and seem to measure up (and Martin certainly likes the sound).

I have 4 drivers that use the same motor design used in the AE drivers. Nick McKinney (R.I.P.) designed this motor and produced a few drivers as Lambda - but he was never a business man. His design was bought by the guy who now runs AE and all the drivers use a version of this. The Apollo upgrade (if they still do this) is certainly worth the money if you intend to push the drivers at all. I've never heard of one breaking, and I seen some of them in some pretty interesting designs (Kyron Audio Gaia is my favourite).

Only $249,000...noice!

Link to post
Share on other sites
22 minutes ago, BLAH BLAH said:

Only $249,000...noice!

I guess, but if you count up the drivers (20), amps (16), control unit, preamp and DSP/DEQX - plus the build quality (pretty darn good), SQ (excellent in a small room), small numbers and bespoke build - it starts to look like reasonable value for the money. Not saying I want a pair...but if they ever came in the front door, I'd be leaving in a coffin before they would.

Link to post
Share on other sites

4 hours ago, tesla13BMW said:

I have been looking also and have the PCB's for the 6 mono amps, power supplies, soft start, speaker protection etc already.  I have the Wild Burro Betsy for mids and GR Reasearch NEO3 for tweeter.

 

For lows I have been looking at the SB Audience Bianco-15OB350.

 

https://www.wagneronline.com.au/sb-audience-bianco-15-open-baffle-woofer-350w/sb-audience-range/sb-acoustics/speaker-drivers/audio-speakers-pa/bianco-150b350-89897/1002168/pd/

 

But, I'm stuck at the point of determining if the 15" will give enough bass without large equalisation boost and considering adding the SB Audience-18SW500.  The problem is if I go 18", 15" then the 8" Betsy that the centre of the Betsy is above ear height.

 

I am avoiding passive crossover design by using a Intel Nuc to do the filters feeding a 8 channel DAC (leaving a pair of channels in case a Sub is warranted).

 

The Betsy wont be the best driver, but, will be a good start to see how the rest of the speaker goes ?

 

Wow....I'm not sure I want to go down the triamping road but the more I read about these designs the more they seem to lean towards this type of connection. If set up this way, are there any crossovers or are you just choosing speakers that integrate well & don't need any manipulation? I would entertain a biamp design as I could still use my Rogue Audio M-180 monoblocks with biamp speaker cables (I could use triamp speaker cables but not sure this would work well?)

 

How would you use the NUC to do the filtering, is this just like another version of room EQ/DSP? How would you integrate this?

 

The Bianco OB woofer looks like a good starting point & at a good price to stuff around with.

 

Cheers

Matt

Link to post
Share on other sites
4 hours ago, MattyW said:

Shallow open back cabinets allow decent bass response from the full range and woofer. A similar result to a far wider baffle with the benefit of being able to baby/pet proof by adding speaker cloth to the back of the cabinet.

 

This is my system a few days ago.... Shallow open back cabinet with fullrange, woofer, front facing ribbons tweeter and ceiling facing bullet compression tweeter.

 

https://drive.google.com/file/d/1ZXGv6xmE4E0smCZsuLEP0bBQG5KAjg-C/view?usp=sharing

 

These cabinets are very heavy, being made of Karri hardwood. Mass helps damp vibration. Likewise I have Dynamat Extreme damping the top and bottom of the cabinet. I may add to the sides at some point also though I doubt there will be any noticeable difference.

 

I like the look & sound of these but I didn't watch the entire video so I'm not sure whether you video'd the back of the speakers.

 

I'm not interested in having very wide baffle speakers, much prefer the panel type like Spatial, Hawthorne & yours etc... Having watched the Hawthorne video I'm liking that design with the upright tube running up the back with a bottom plate as this seems relatively easy to manufacture?

 

Cheers

Matt

Link to post
Share on other sites

 

18 minutes ago, mattjtaylor2809 said:

 

I like the look & sound of these but I didn't watch the entire video so I'm not sure whether you video'd the back of the speakers.

 

I'm not interested in having very wide baffle speakers, much prefer the panel type like Spatial, Hawthorne & yours etc... Having watched the Hawthorne video I'm liking that design with the upright tube running up the back with a bottom plate as this seems relatively easy to manufacture?

 

Cheers

Matt

 

Well, here are some older photo's of the speakers. Due to the lower efficiency of the woofers I bi-amp. 6WPC driving the fullrange and tweeters, and 400WPC (4ohms) for the woofer..... In fairness though the power amp on the woofer is set to only slightly over a quarter power. Massive overkill.

 

IMG_1585311951621.thumb.jpg.dd1dc4deb681a678964adf4ed8910d2b.jpg

 

IMG_1585312385437.thumb.jpg.9fedc6d7ff55f832007a7fda27b55e59.jpg

 

IMG_20191126_182758.thumb.jpg.d489e8fb3e6cfa32ee8f5027c112086c.jpg

 

These caps are no longer there. They've been changed for a single 2.2uf Duelund CAST Cu-Sn

IMG_20191126_182817.thumb.jpg.b6f840ea855c5bede0432d039e9ef557.jpg

Edited by MattyW
  • Like 1
Link to post
Share on other sites

Thanks MattyW,

 

Kind of a hybrid design then with the open back of the cabinet.....you did mention this but it didn't twig until I saw the photos.

 

How much of diff does the ceiling firing tweeter make? Finally, the cap(s) are to regulate frequency/current to the tweeters, other than that, no crossovers?

 

Cheers

Matt

Link to post
Share on other sites
5 minutes ago, mattjtaylor2809 said:

Thanks MattyW,

 

Kind of a hybrid design then with the open back of the cabinet.....you did mention this but it didn't twig until I saw the photos.

 

How much of diff does the ceiling firing tweeter make? Finally, the cap(s) are to regulate frequency/current to the tweeters, other than that, no crossovers?

 

Cheers

Matt

 

The upfiring tweeter is just to get around phase issues as it's not dipole..... The Aurum Cantus G3Si ribbons are closed back too but I found I just can't do without ribbons in the mix as they bring incredible detail.

 

The cap is simply to drop the level of the tweeters below around 6000Hz or so. Seems to work beautifully. It's the only kind of limitation I have. I may change my Behringer KM750 power amp on the woofers for a Samson SXD5000 at some point so I can limit how high a frequency the woofers go.

Link to post
Share on other sites
1 hour ago, mattjtaylor2809 said:

 

Wow....I'm not sure I want to go down the triamping road but the more I read about these designs the more they seem to lean towards this type of connection. If set up this way, are there any crossovers or are you just choosing speakers that integrate well & don't need any manipulation? I would entertain a biamp design as I could still use my Rogue Audio M-180 monoblocks with biamp speaker cables (I could use triamp speaker cables but not sure this would work well?)

 

How would you use the NUC to do the filtering, is this just like another version of room EQ/DSP? How would you integrate this?

 

The Bianco OB woofer looks like a good starting point & at a good price to stuff around with.

 

Cheers

Matt

Hi Matt

 

No there will be crossovers done in the digital domain.  rePhase will be used to produce the filters and Equaliser APO to perform the task.

 

http://jdm12.ch/Audio/2016_Windows-DSP.asp gives you an idea of what is involved.  Thank fully I have someone who has gone down this route and will assist as I'm only just getting into anything other than vinyl and cd :frantics:.  The other challenge will be getting the analogue from the LP12 into the system.

  • Like 1
Link to post
Share on other sites
17 minutes ago, deblur said:

Saw this on Audio Dandy website.

http://www.modelpromo.nl/Liionidas Open Baffle Platform.htm

Very reasonable cost.

I am using AE 15" drivers in sealed box subs. Very happy.

You can't go wrong with their drivers if in your budget.

 

Yeah, Leon Huijgen does quite bit for the community online.  The new Lii Audio Silver 10 are meant to be exceptional and do not require helper tweeters.

 

My Fast-10S are two generations earlier and definitely need the helper tweeters.

Edited by MattyW
Link to post
Share on other sites

If I only I spoke Dutch.....unless there is an English translation?

 

Amazing how much info is out there.

 

27 minutes ago, tesla13BMW said:

http://jdm12.ch/Audio/2016_Windows-DSP.asp gives you an idea of what is involved.  Thank fully I have someone who has gone down this route and will assist as I'm only just getting into anything other than vinyl and cd :frantics:.  The other challenge will be getting the analogue from the LP12 into the system.

 

You're heads spinning ? I enjoy the learning though!

 

32 minutes ago, deblur said:

Saw this on Audio Dandy website.

http://www.modelpromo.nl/Liionidas Open Baffle Platform.htm

Very reasonable cost.

I am using AE 15" drivers in sealed box subs. Very happy.

You can't go wrong with their drivers if in your budget.

 

Can these AW 15" drivers be used OB or do they need to be in a cabinet?

Link to post
Share on other sites
On 01/12/2020 at 6:17 PM, mattjtaylor2809 said:

I could end up just buying some Spatial's or PureAudioProject or speakers made by Walter Liederman (Emerald Physics).

 

I have some spatial speakers that you would be welcome to listen to if you like to get an idea of sound?

I have modified the xover with better caps and inductors which improved them a fair bit imho 

 

cheers

Peter

Link to post
Share on other sites
16 hours ago, peterpan said:

 

I have some spatial speakers that you would be welcome to listen to if you like to get an idea of sound?

I have modified the xover with better caps and inductors which improved them a fair bit imho 

 

cheers

Peter

 

Hi Peter,

 

Yes please, I think the more I listen to OB speakers, the better at this stage. I'll be back in touch.

 

Matt

Link to post
Share on other sites

I haven't read all the posts here but I would just like to say that IMO OB speakers look sooooo much better.

I would gladly have them in my room just for that reason alone :)

Good luck with yours.

Link to post
Share on other sites

Just use Google Translate to translate pages that are not in English. See here: https://translate.google.com/translate?sl=auto&tl=en&u=http://www.modelpromo.nl/Liionidas%20Open%20Baffle%20Platform.htm

 

If I had my time over I'd get this and install a pair of Silver 10 and W15 drivers and be done with it. Incredible value.

Edited by MattyW
  • Like 1
Link to post
Share on other sites
21 hours ago, mattjtaylor2809 said:

Can these AW 15" drivers be used OB or do they need to be in a cabinet?

AE do dipole drivers, especially designed to work in an open baffle.

Depending on room size you may need 2 per side to overcome cancellations, an effect of open baffle design.

Link to post
Share on other sites
5 hours ago, mattjtaylor2809 said:

 

 

Yes please, I think the more I listen to OB speakers, the better at this stage. I'll be back in touch.

 

Matt

 

@mattjtaylor2809

 

Likewise - I have similar speakers to PeterP. Matt, you are very welcome to come over for a listen. Mine are the Spatial Hologram M3 Turbo.

 

Cheers,

 

G

Link to post
Share on other sites
2 hours ago, MattyW said:

Just use Google Translate to translate pages that are not in English. See here: https://translate.google.com/translate?sl=auto&tl=en&u=http://www.modelpromo.nl/Liionidas%20Open%20Baffle%20Platform.htm

 

If I had my time over I'd get this and install a pair of Silver 10 and W15 drivers and be done with it. Incredible value.

 

Thanks for the translation, I was trying to do this & you then sent the link.

 

Looks like you can buy the drivers he uses which the author rated more highly than his PureAudioProject drivers....which are supposed to be pretty good!

 

https://www.lii-audio.com/shop/

 

I've also downloaded the specs for his Liionidas design, not my favorite design but certainly easier enough to make, especially with the specs?

  • Like 1
Link to post
Share on other sites

If there are any Melb folks willing to demo their OB setup I am keen to have a listen. Has been a long time since I have heard some. Would love to hear the puraudioprojects especially but any / all are of interest.

Link to post
Share on other sites
43 minutes ago, mattjtaylor2809 said:

 

Thanks for the translation, I was trying to do this & you then sent the link.

 

Looks like you can buy the drivers he uses which the author rated more highly than his PureAudioProject drivers....which are supposed to be pretty good!

 

https://www.lii-audio.com/shop/

 

I've also downloaded the specs for his Liionidas design, not my favorite design but certainly easier enough to make, especially with the specs?

 

Keep in mind that the F15 are an older driver. The Crystal are better,  and Silver better again.  Leon rates the silver as the best he's used. He's an active member on a few Facebook speaker groups.

Link to post
Share on other sites

Looking at the SPL Vs Frq charts, the Silver 8 chart doesn't look that great with a dB diff of 20+ between 20-100 Hz whereas the Crystal 10 only seems to have a variance of about 10 dB for the same frequency range?

 

Crystal 10 $999 US Pair - only 10 dB diff between 20-10 Hz & nice flat curve thereafter.

They do suggest best driven via low power tubes but I have Rogue Audio M-180 monoblocks @ 180 watts ea. side?

 

image.png.7d8f7e347a103b78a71a311a9ba11080.png

 

 

Silver 8 - $399 Pair - 20 dB diff between 20 - 100 Hz

 

image.png.570f4fb3ccf4051f5392acf4b5714e99.png

 

 

F-15 Full Range Driver - $399 pair - also roughly 20 dB diff between 20-100 Hz

 

image.png.5d0e19debd2bc87913a142fa60400a04.png

 

Finally, this is the range in dB of the W-15 woofer

 

image.png.5e7a7440f17057f60a3d09132c9b6d4b.png

 


Maybe all this doesn't matter when in combination with the F15 & with his XO?

 

I'd prefer a 10 - 15" full range driver to complement with woofer but the Silver 10 at $1,199 US is starting to become a bit too expensive for a "side project" but as he says in the article, they are exchangeable as the XO will support all combos?

 

Am I looking at the wrong things?

 

Cheers

Matt

 

Link to post
Share on other sites
1 hour ago, Jone5y said:


Have you been tempted by the M3 Sapphires at all?

 

Not me - no. I'm quite happy with what I have. They do the job for both stereo and HT.

Link to post
Share on other sites
  • Recently Browsing   0 members

    No registered users viewing this page.



×
×
  • Create New...