DYI Open-Baffle Speakers - is it hard to do?

KPC

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An major audio reviewer visited Nelson Pass’s home and loved Nelson’s homemade Open-Baffle Speakers. I got a list of speaker transducers and crossover components but have no idea if I’ve enough ability or need help to construct.

Although I’m a fairly intellectual analytical guy, my knowledge of electronics is very rudimentary/non-existent.

Online research was fruitless - all I get when researching how to set up crossovers is subwoofer integration.

1) Is DIY Open-Baffle Speakers beyond just mounting on boards, wiring and fittings, adjusting the crossover, or...?

2) Is it difficult to set the crossover?

3) Should I try to get guidance/help especially with setting crossover?
 
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bonzo75

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An major audio reviewer visited Nelson Pass’s home and loved Nelson’s homemade Open-Baffle Speakers. I got a list of speaker transducers and crossover components but have no idea if I’ve enough ability or need help to construct.

Although I’m a fairly intellectual analytical guy, my knowledge of electronics is very rudimentary/non-existent.

Online research was fruitless - all I get when researching how to set up crossovers is subwoofer integration.

1) Is DIY Open-Baffle Speakers beyond just mounting on boards, wiring and fittings, adjusting the crossover, or...?

2) Is it difficult to set the crossover?

3) Should I try to get guidance/help especially with setting crossover?

Not heard any but there are guys on audio circle and DIY forum with some excellent drivers who own them. All you need apart from the drivers seems to be a plane of wood cut to certain length and breadth with a slit in the middle. And borrow someone's crossover to start with. Assembling it should be simple but best you should visit some people who own them, as different drivers and crossovers will lead to very different sounds, and you should build the one you like the sound of
 

morricab

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Not heard any but there are guys on audio circle and DIY forum with some excellent drivers who own them. All you need apart from the drivers seems to be a plane of wood cut to certain length and breadth with a slit in the middle. And borrow someone's crossover to start with. Assembling it should be simple but best you should visit some people who own them, as different drivers and crossovers will lead to very different sounds, and you should build the one you like the sound of
Getting the bass right is a challenge...
 
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kach22i

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Getting the bass right is a challenge...
I watched a video last month where I think it was the manufacturer of an L-Baffle speaker explain the room loading differences for bass with open baffle. In short, no great disparity of pressure as with sealed boxes (he hated ports even more), so loading was more natural and akin to live instruments.
 

bonzo75

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Getting the bass right is a challenge...

In this design you can load a lot of woofers facing each other across the slit, so you can get a lot of natural bass. People have done as much as 8 to 16 pairs of woofers.
 

kach22i

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Sounded like bonzo75 has seen this specific design, so I did an image search.

A Pinterest image was sourced from an article, and it is for all to see if you follow the link below.

2011
The Slot Loaded Open Baffle Project
Article By Nelson Pass

http://www.enjoythemusic.com/diy/0911/slot_loaded_open_baffle_speaker.htm
REAR.jpg SYSTEM.jpg

If I were to try and make this with my own twist, I'd make it out of polycarbonate or acrylic so that I could see through it (and edge light it with LED's).

And also add a dipolar supertweeter, a ribbon or EMIT at the top for greater sense of air.

Don't get me wrong, I bet they look and sound great "as is", but I want to have just as much fun as the master.

EDIT:

Other opposing woofers like this I've seen do not have the back plate closing it off.
 
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KPC

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@kach22i
When Stereophile's Herb Reichert visited famous amplifier designer Nelson Pass's home, he loved the sound of Nelson's open baffle speakers: https://www.stereophile.com/content/gramophone-dreams-26-nelson-pass-harmonic-distortion-page-2

So I'm wondering if I got a list of the driver and crossover components, can I get close to constructing/duplicating Nelson's speakers? I'm more interested in owning than building.

My expertise lies along a analytical/logical home handyman with Youtube (future) skillset. My electronics background is limited to handheld flashlight electrical schematics and a handful of electronic symbol recognition (resistors, capacitors...). So I'm trying to gauge, Can I do it? Can I do it with further knowledge and/or assistance? Am I better off hiring someone to build for me?

Also, for speakers I was told, "Easy to get frequency response even but difficult to get phase response" - I'm not sure what this means/entails.
 
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bonzo75

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@kach22i
When Stereophile's Herb Reichert visited famous amplifier designer Nelson Pass's home, he loved the sound of Nelson's open baffle speakers: https://www.stereophile.com/content/gramophone-dreams-26-nelson-pass-harmonic-distortion-page-2

So I'm wondering if I got a list of the driver and crossover components, can I get close to constructing/duplicating Nelson's speakers? I'm more interested in owning than building.

My expertise lies along a analytical/logical home handyman with Youtube (future) skillset. My electronics background is limited to handheld flashlight electrical schematics and a handful of electronic symbol recognition (resistors, capacitors...). So I'm trying to gauge, Can I do it? Can I do it with further knowledge and/or assistance? Am I better off hiring someone to build for me?

Also, for speakers I was told, "Easy to get frequency response even but difficult to get phase response" - I'm not sure what this means/entails.

You will be able to build it, but you will never be able to guess what driver and crossover combination to use unless you hear a few yourself.
 

morricab

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Sounded like bonzo75 has seen this specific design, so I did an image search.

A Pinterest image was sourced from an article, and it is for all to see if you follow the link below.

2011
The Slot Loaded Open Baffle Project
Article By Nelson Pass

http://www.enjoythemusic.com/diy/0911/slot_loaded_open_baffle_speaker.htm
View attachment 66500 View attachment 66501

If I were to try and make this with my own twist, I'd make it out of polycarbonate or acrylic so that I could see through it (and edge light it with LED's).

And also add a dipolar supertweeter, a ribbon or EMIT at the top for greater sense of air.

Don't get me wrong, I bet they look and sound great "as is", but I want to have just as much fun as the master.

EDIT:

Other opposing woofers like this I've seen do not have the back plate closing it off.
Interesting, I have seen/heard something like this before but not with so many woofers (instead bigger woofers). I remember being fairly impressed with the sound but this was a long time ago now. The more standard way of doing the OB design with a couple of big woofers on the front also can work well but needs either a really wide baffle or side cheeks to help reduce midbass cancellation.
 

kach22i

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I could work with the vertical bass slot as a design element and continue the slot upward with open ribbons.

This would in affect look like two slimmer panels.

As far as crossovers and the like, I've avoided them in my prototypes. Just used a cap to protect the tweeter and ran the mid/woofer full range. Then used an L-pad to balance the tweeter output. Subwoofer added as part of a 3-piece system is perhaps easier to execute.

If your heart is set on adding electronics to your signal, there are published designs out there. Perhaps modifying one of those designs into the Pass configuration will work.

As I read the article, bass front and aft of the baffle was near equalized 9 feet out at listening position and starting to cancel each other out.

Is this what you want?

Could be worse I guess.
 

kach22i

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From 2015 more Slot Loaded Open Baffle (SLOB).

https://audiokarma.org/forums/index.php?threads/open-baffle-epiphany.566879/page-56
The slot loaded woofer used by Mr. Pass is an Eminence 4015LF. PE's price is $225 each. It's 96 dbs which means it won't require massive power.

$225 X 12 = $2,700

I read somewhere that with conventional box speakers the enclosures are 75 percent of the costs.

So at least you save on most of that, plus the time.

EDIT:

I'm surfing through that AK thread above that I posted, and someone mentions a speaker I never heard of before. So different that I have to share.

http://www.vintagehificlub.com/quot...near/attachment/phase-linear-andromeda-iii-2/
phase-linear-andromeda-III-2.jpg

More images here:
https://www.audioasylumtrader.com/ca/listing/Speakers-Full-Range/Phase-Linear/Andromeda-III/30588

Better looking with clothes on.

https://www.hifiengine.com/manual_library/phase-linear/andromeda-iii.shtml
phase_linear_andromeda_iii.jpg

A Bob Carver design that last link says in the comments section.

EDIT-2:

Gotta love the $50 kitchen cabinet door speaker.

https://www.audiocircle.com/index.php?topic=154866.0
 
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KPC

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Guess I’ll postpone this DIY speaker project until I get more knowledge/experience, which leads to:

How did you get your knowledge on building speakers?

Any suggestions on how I can increase my knowledge to the point on being able to build these open baffle speakers?
 

pjwd

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Guess I’ll postpone this DIY speaker project until I get more knowledge/experience, which leads to:

How did you get your knowledge on building speakers?

Any suggestions on how I can increase my knowledge to the point on being able to build these open baffle speakers?
Not sure if you have been directed to linkwitz site
Read that first
Then look up diyaudio .. heaps of knowledgeable folks ... this guy being one of them
http://gainphile.blogspot.com/?m=1

Dont get fixated on slot loaded baffle and dont try to do a passive xover
It's a steep learning curve
P
 

bonzo75

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Guess I’ll postpone this DIY speaker project until I get more knowledge/experience, which leads to:

How did you get your knowledge on building speakers?

Any suggestions on how I can increase my knowledge to the point on being able to build these open baffle speakers?

You have to listen to a few to know what type of drivers you like, then understand the cross over. It's best to physically meet people who have done this, understand, see differences in their system. You will have to be patient till the virus eases and you can visit people
 

Don Reid

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I agree with the suggestion to visit the Linkwitz website. It's an education. Also, Nelson Pass is famous for being friendly and helpful to DIYers. If you just ask him he might well send you a parts list and crossover schematic. You shouldn't borrow someone else's crossover unless it's for use with identical speakers. Speakers are very idiosyncratic.
 

DasguteOhr

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First of all, you need to tell us how big is the room that you plan to place speakers in.
Open baffles take up space at the back of the wall to play well.
second up to which frequency in the bass play physical it goes up to about 30Hz. deeper becomes difficult you can only rectify electronically(dsp)mostly sounds very modest.
In order to get the right bass up to the resonance frequency of the bass chassis, only those with a higher than Qts 0.8 are possible.
With smaller values there is too much level loss in the bass. which can only be picked up again on DSP.
So first find the right chassis then it goes to the baffle.
Do you want the speakers to work completely as a dipole also in the tweeter? Then there are two options a horn driver that can be opened at the back, or a foil tweeter like AMT.
Question after question ... here are a few chassis I can recommend - they work very well.
B&C de250 Horndriver really good near TAD you need no Frequency Correction
From 2khz-19 khz my Driver needs Lpad resistors and capacitor 12dB xover http://www.sengpielaudio.com/calculator-Lpad.htm
For mids and upper bass
Alnico red ToneTubby 12"woofer16 Ohm works from 70hz -2khz really good near 100db needs no xover. Look at specs
For Bass a Ripol is best and easy Option.30hz to 80hz with active xover
amplifer modul Class D small and lot of power.
SubRStRipol.jpg
Exsample like this
3.jpg
 

MRJAZZ

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From 2015 more Slot Loaded Open Baffle (SLOB).

https://audiokarma.org/forums/index.php?threads/open-baffle-epiphany.566879/page-56


$225 X 12 = $2,700

I read somewhere that with conventional box speakers the enclosures are 75 percent of the costs.

So at least you save on most of that, plus the time.

EDIT:

I'm surfing through that AK thread above that I posted, and someone mentions a speaker I never heard of before. So different that I have to share.

http://www.vintagehificlub.com/quot...near/attachment/phase-linear-andromeda-iii-2/
View attachment 66550

More images here:
https://www.audioasylumtrader.com/ca/listing/Speakers-Full-Range/Phase-Linear/Andromeda-III/30588

Better looking with clothes on.

https://www.hifiengine.com/manual_library/phase-linear/andromeda-iii.shtml
View attachment 66552

A Bob Carver design that last link says in the comments section.

EDIT-2:

Gotta love the $50 kitchen cabinet door speaker.

https://www.audiocircle.com/index.php?topic=154866.0
The Andromeda III ( a Bob Carver design) was a very interesting speaker back in the day....definitely could compete with the better “ panel, dipole “ speakers than (“Maggie’s”, etc.), and with much better dynamics’s.....Was a very interesting design for it’s time...
Cheers.....
 

kach22i

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Apr 21, 2010
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www.kachadoorian.com
The Andromeda III ( a Bob Carver design) was a very interesting speaker back in the day....definitely could compete with the better “ panel, dipole “ speakers than (“Maggie’s”, etc.), and with much better dynamics’s.....Was a very interesting design for it’s time...
Cheers.....
Just a suggestion, but there is a vintage section of the forum.

So it's not lost to the winds of time, maybe a more complete review of speakers we may never be able to hear in person because they no longer exist?

I'm sure it is more than fair criticism to dispute accuracy of 30-40-50 year old memories, but it could be a fun exercise for some to jog their own memory.

If I live another 40 years and make it to 100, will any of the young folk care to hear the old man go on about those ancient internal combustion engines that spewed filth into the air?
 

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