Progress update for this week.. Spent a good bit of yesterday working with my friend, Mark on the cabinets. We spent a few hours mixing various dye possibilities for the finish on the veneers. Still working on final solution for that. The rest of the afternoon was spent cutting front panels and getting driver holes finished. We cut the front panels slightly oversized, than used the router table with flush cut bit to get each panel to fit perfectly. Cut domino holes, next then on to the speaker holes. Back panels are up next then glue up of panel, and likely begin the veneers soon after that. We still have to finish the plan for the plinths and get them going.. This has been such a fun project with lots of "mini projects" along the way. Can't wait to listen to them with my Pass M2!
When I grow up, I want to have a workshop like this. 👍
I was thinking the same thing - I have a Router and not much else - But great work and thanks for posting the pictures it helps clarify the process.
My wood is on the way. Post pitures of the Veneer process because I don't have a clue about that -- I am learning as I go
My wood is on the way. Post pitures of the Veneer process because I don't have a clue about that -- I am learning as I go
Me too! Grateful for a friend willing to share his tools, space, and talent. Also appreciative of your expertise as well! Thanks for all the hard work, and for continuing to be engaged to help guys like me!
@tbrooke You're welcome, I'll continue to take pictures along the way. As far as tools, I"m in same boat.. Handfull of "weekend warrior/happy homeowner" tools, and that's about it. Did you order the large sheets of uncut ply, or did you order and have pre-cut like @Sorenm did?
Veneer process will be interesting. I"m going to bring the cabinets home and attempt to tackle that part of the process on my own. My friends shop is a 45 min drive from me and we are lucky to get 1 day per week to work on these. So the veneer process would take a LONG time if we do it together. I'll admit I have a little anxiety over that part of the process myself!
I don't really need to engage here... but ...curious if you have heard these speakers in person—or built them—or looked at the paper on them? What's the relationship between wood-pros and bracing? Or perhaps, how one might objectively measure "ring" related to a baffle? (In this case where the dimensions of all components and cabinets and related build factors are extremely tight dimensionally and a ton of analysis has been done—see paper).
Not defending anything here—To each their own—I suppose I just like to read comments that are constructive since I always learn things and maybe we all benefit? And it's a Herculean effort to build these....
I think turbowatch has a point, one does not have to build this particular speaker to form a view on bracing. I think he merely wanted to point out that wood pros don’t know about the finer points of speaker enclosure design.
The OSMC was not designed as BBC-type speaker where panel resonances are factored into the sound. The simplistic enclosure of the OSMC was raised as a concern several times during the design phase. I added a third brace and changed the shapes so that all braces connect to the front panel. I obviously had to make the speaker deeper to keep the volume roughly constant.
But the other builders did not deviate from the design and are happy with the sound. Maybe panel resonances accidentally help the sound of the OSMC? There is no way there are none if built as designed.
The OSMC was not designed as BBC-type speaker where panel resonances are factored into the sound. The simplistic enclosure of the OSMC was raised as a concern several times during the design phase. I added a third brace and changed the shapes so that all braces connect to the front panel. I obviously had to make the speaker deeper to keep the volume roughly constant.
But the other builders did not deviate from the design and are happy with the sound. Maybe panel resonances accidentally help the sound of the OSMC? There is no way there are none if built as designed.
The box design was kept simple because of the design goals as described in the first post of this thread: The box should be easy enough to make on a kitchen table.
If you want to add braces, go for it and have fun. However, a layer of Hawaphon would be much more effective to reduce panel resonances.
If you want to add braces, go for it and have fun. However, a layer of Hawaphon would be much more effective to reduce panel resonances.
@SkyPirate - I ordered my wood precut from Oooch. Just the other day so I don't beleive that it has shipped yet.
MaxiMax77, I'm a bit confused by this. I'm arguably clueless when it comes to designing speaker cabinets. Are you and Turbowatch seeing something in my execution of the OSMC plans that is incorrect, or are you just in disagreement with Matthias work on this project in general? What does "Wood pro" mean and how does that correlate to a lack of knowledge regarding cabinet design? Could there be someone who is knowledgeable about woodworking, and also cabinet design? Are these mutually exclusive? I've not read anything from anyone who's built these who hasn't been thrilled by the outcome in terms of their sound.
I know that some oppose serious bracing cabinets for various reasons.
In general people that are used to build things from wood have some very realistic views how to do that. So if they build a toy house for children they will make it stand that abuse, a living room table may have another kind of strength. I have been working with carpenters for many years and know how they "see" solid. From their practical education they do not understand that a box that can even stand the weight of an African elephant, may resonate when used for sound reproduction. In most cases they go for stronger walls if you tell them to make it more "solid". The concept of reasonable panel thickness and stripes applied to the inside makes no sense in their world, as it does not improve any of the the criteria they see and have been taught.
The complicated braces we see in many builds often are copied like godspell, while the concept of consequent and simple bracing is not understood. This is not limited to wood pro's.
If one ever build a speaker cabinet with a matrix like braceing, he will be surprised how solid and acoustical dead someting like 3/4" fibre or paricle board can get. Just some boring stripes of wood material consistently glued on any inner surface, dividing them into squares and rectangles of different sizes. No fancy design or secret formula, just plain simple work and a usual material. Inexpensive and easy to do.
If you tell someone you can tell where to put braces, just by knocking& listening, this is often meet with laughter. Sure you can start a finite elements analysis or attach accelerometers, but in the end you want to build something made for listening, so why not listen to the object?
This specific box design for the OSMB is as good as many expensive, well known brands will make cabinets, but far from resonace free. The braceing is the extreme minimum, made acoustically transparent inside, simple to build and of low parts count. Just knock on it from the outside and you will hear how the sound changes over the surfaces, from solid to hollow and resonant.
Sure, the speaker will work, but with more narrow, simple stripes, the bass will be tighter. This is just a simple fact, which anyone can proof by trying. It works for closed and vented cabinets.
I attach a picture of a subwoofer that has some very simple and cheap braceing, calming down low frequency resonances. This example is not the optimum, but will work for the cause.
PS this sub is build from recycled wood and leftovers. The outside is very nice verneer.
In general people that are used to build things from wood have some very realistic views how to do that. So if they build a toy house for children they will make it stand that abuse, a living room table may have another kind of strength. I have been working with carpenters for many years and know how they "see" solid. From their practical education they do not understand that a box that can even stand the weight of an African elephant, may resonate when used for sound reproduction. In most cases they go for stronger walls if you tell them to make it more "solid". The concept of reasonable panel thickness and stripes applied to the inside makes no sense in their world, as it does not improve any of the the criteria they see and have been taught.
The complicated braces we see in many builds often are copied like godspell, while the concept of consequent and simple bracing is not understood. This is not limited to wood pro's.
If one ever build a speaker cabinet with a matrix like braceing, he will be surprised how solid and acoustical dead someting like 3/4" fibre or paricle board can get. Just some boring stripes of wood material consistently glued on any inner surface, dividing them into squares and rectangles of different sizes. No fancy design or secret formula, just plain simple work and a usual material. Inexpensive and easy to do.
If you tell someone you can tell where to put braces, just by knocking& listening, this is often meet with laughter. Sure you can start a finite elements analysis or attach accelerometers, but in the end you want to build something made for listening, so why not listen to the object?
This specific box design for the OSMB is as good as many expensive, well known brands will make cabinets, but far from resonace free. The braceing is the extreme minimum, made acoustically transparent inside, simple to build and of low parts count. Just knock on it from the outside and you will hear how the sound changes over the surfaces, from solid to hollow and resonant.
Sure, the speaker will work, but with more narrow, simple stripes, the bass will be tighter. This is just a simple fact, which anyone can proof by trying. It works for closed and vented cabinets.
I attach a picture of a subwoofer that has some very simple and cheap braceing, calming down low frequency resonances. This example is not the optimum, but will work for the cause.
PS this sub is build from recycled wood and leftovers. The outside is very nice verneer.
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@Turbowatch2 There are many different thought schools when it comes to "acoustically dead" boxes and bracing. However, unfortunately, many are simply based on hearsay without providing hard data. I am aware of the the measurements done by Bernd Timmermanns a few years back in the Hobby HiFi magazine, and my own semi-scientific evaluation of the infamous "knock test". If you have additional data, I'm all ears!
@SkyPirate Your build is just great! If you feel like you want to make your enclosures "deader" at some point down the road you can still add more bracing -- but instead I'd recommend adding a layer of Hawaphon on the insides, which will be easier and more efficient in my experience. I didn't feel the need for more bracing or Hawaphon with my OSMCs though -- they sound clean and transparent as they are.
@SkyPirate Your build is just great! If you feel like you want to make your enclosures "deader" at some point down the road you can still add more bracing -- but instead I'd recommend adding a layer of Hawaphon on the insides, which will be easier and more efficient in my experience. I didn't feel the need for more bracing or Hawaphon with my OSMCs though -- they sound clean and transparent as they are.
This is the best I’ve seen so far. It’s not behind a paywall.
https://www.somasonus.net/box-construction-methods
Donate @augerpro
if you are able!
The other thing I want to comment on is that although there may be not openly published data for peer review; Eg. Academic articles for peer review, this does not mean it doesn’t exist.
Ur
In fact; sometimes it’s kept in-house as a “trade secret” as to become to be a competitive advantage.
At other times, things are published as a “white papers” are a form of marketing.
There is no data is the not the same “as best we know, generally the data doesn’t support that”
https://www.somasonus.net/box-construction-methods
Donate @augerpro
if you are able!
The other thing I want to comment on is that although there may be not openly published data for peer review; Eg. Academic articles for peer review, this does not mean it doesn’t exist.
Ur
In fact; sometimes it’s kept in-house as a “trade secret” as to become to be a competitive advantage.
At other times, things are published as a “white papers” are a form of marketing.
There is no data is the not the same “as best we know, generally the data doesn’t support that”
@mbrennwa I don't have any scientific results. Even if I had some, I probaply would not post them, because of the many different oppinions about building a speaker cabinet and the following dispute.
Maybe let's have a look why people like to make things complicated. Not only in DIYS by the way, but in any aspect of life. Often there is a financial interest involved. People selling speaker kit's or plan's want to make others believe there is some magical knowledge needed to design a speaker cabinet.
On the other side are DIYS builders, that read about many ideas, but are unable to decide what to do and buy best. They have a huge problem in evalueating different aspects of a speaker build. For example they are unsure if simple, wooden braces are more important than an expensive speaker terminal, a cable or some boutique capacitor. They even fear that some additonal brace may "change the sound". Those are easy prey for snake oil sellers, that are lurking behind any corner of HIFI and HIFI-DIYS.
Loudspeakers are a more or less simple, all physical object. There are clear rules if you don't believe in alternative facts.
A resonating cabinet stores energy and returns it after a small moment. You want the speaker to reproduce exactly what the electical input was, without delay, so this is bad. Very, very simple: A cabinet has to be 100% neutral, inside and outside.
If you have an object that is resonating, produces harmonics and radiate them into the room, you have a musical instrument, not a speaker.
Over time there have been a lot of curious speaker builds. Those have been made in a certain way because of electronics and materials available in that area, unaviable advanced measureing systems and scientific mistakes. The BBC developer were great in making mistakes and arrogantly preserve them later. Probably their superiors pressured them to get results and had no understanding that research often comes at a price, but doesn't deliver useable products. They were told to build someting useable, not to do university research. Many of their "research papers" are quite curious if you read them today. Results are somehow far-fetched.
Of course there are clever salesmen that still market these funny "monitor speaker" they made half a century ago. A result, that a simple, sturdy plywood box would be best for a monitor, would have gotten the BBC developers fired after all that expensive, time consuming "research". So it had to lead to some very different, complicated speaker construction. To which some still give divine veneration today. Did you never ask why no leading studio monitor brand still uses such "BBC cabinets"?
You mentioned a very expensive damping material, called Hawafon. It would be a great idea to cover the inner walls of a cabinet that is carefully braced with some wood matrix. Anyway, at this stage of bracing, the Hawafon may only give a few percent measurable improvement, but multiply the build's cost. So best leave it in the machinery that it is supposed to make less noisy and use some wood and glue.
You also wrote about what Bernd Timmermann once did. He made a great and quite logical test of different approaches to silence walls of speaker cabinets. If you make an analysis of what gives you the best speaker cabinet at lowest cost, you get some surprising results. In the end some of the cheapest material, used in a clever way, is just as good or better than many expensive ideas.
Today Mr. Timmermann, like any other audio publication, is a slave to advertising. His promotion of completely overpriced crossover parts, while being blind to any cost effective alternative and his use of ridiculously expensive damping materials has nothing to do with sound quality any more.
Just as he completely ignores the active DSP solutions that today are less expensive than one of his "Mundorf high end crossovers". Easy to understand, because the vendors of this active, low cost, high quality stuff do not buy advertisements in his magazine.
Mr. Timmermann is just an example.Others, may it be print media or internet publications, just as Youtuber's and the like, are all the same.
Sad as it is, even the once fantastic speaker builds from the Klang&Ton and Hobby HIFI magazine are becoming more and more questionable. Some seem to be just promotion of below average constructions, not honest review's any more.
Today crossover parts and damping materials are often more expensive than the very good, high class drivers in those builds. No research, just relabeling of industry parts "for audio", justify prices that are tenfold the regular sales price. Of course, these sellers of audio products can spend huge amounts on advertising.
This world sucks.
Maybe let's have a look why people like to make things complicated. Not only in DIYS by the way, but in any aspect of life. Often there is a financial interest involved. People selling speaker kit's or plan's want to make others believe there is some magical knowledge needed to design a speaker cabinet.
On the other side are DIYS builders, that read about many ideas, but are unable to decide what to do and buy best. They have a huge problem in evalueating different aspects of a speaker build. For example they are unsure if simple, wooden braces are more important than an expensive speaker terminal, a cable or some boutique capacitor. They even fear that some additonal brace may "change the sound". Those are easy prey for snake oil sellers, that are lurking behind any corner of HIFI and HIFI-DIYS.
Loudspeakers are a more or less simple, all physical object. There are clear rules if you don't believe in alternative facts.
A resonating cabinet stores energy and returns it after a small moment. You want the speaker to reproduce exactly what the electical input was, without delay, so this is bad. Very, very simple: A cabinet has to be 100% neutral, inside and outside.
If you have an object that is resonating, produces harmonics and radiate them into the room, you have a musical instrument, not a speaker.
Over time there have been a lot of curious speaker builds. Those have been made in a certain way because of electronics and materials available in that area, unaviable advanced measureing systems and scientific mistakes. The BBC developer were great in making mistakes and arrogantly preserve them later. Probably their superiors pressured them to get results and had no understanding that research often comes at a price, but doesn't deliver useable products. They were told to build someting useable, not to do university research. Many of their "research papers" are quite curious if you read them today. Results are somehow far-fetched.
Of course there are clever salesmen that still market these funny "monitor speaker" they made half a century ago. A result, that a simple, sturdy plywood box would be best for a monitor, would have gotten the BBC developers fired after all that expensive, time consuming "research". So it had to lead to some very different, complicated speaker construction. To which some still give divine veneration today. Did you never ask why no leading studio monitor brand still uses such "BBC cabinets"?
You mentioned a very expensive damping material, called Hawafon. It would be a great idea to cover the inner walls of a cabinet that is carefully braced with some wood matrix. Anyway, at this stage of bracing, the Hawafon may only give a few percent measurable improvement, but multiply the build's cost. So best leave it in the machinery that it is supposed to make less noisy and use some wood and glue.
You also wrote about what Bernd Timmermann once did. He made a great and quite logical test of different approaches to silence walls of speaker cabinets. If you make an analysis of what gives you the best speaker cabinet at lowest cost, you get some surprising results. In the end some of the cheapest material, used in a clever way, is just as good or better than many expensive ideas.
Today Mr. Timmermann, like any other audio publication, is a slave to advertising. His promotion of completely overpriced crossover parts, while being blind to any cost effective alternative and his use of ridiculously expensive damping materials has nothing to do with sound quality any more.
Just as he completely ignores the active DSP solutions that today are less expensive than one of his "Mundorf high end crossovers". Easy to understand, because the vendors of this active, low cost, high quality stuff do not buy advertisements in his magazine.
Mr. Timmermann is just an example.Others, may it be print media or internet publications, just as Youtuber's and the like, are all the same.
Sad as it is, even the once fantastic speaker builds from the Klang&Ton and Hobby HIFI magazine are becoming more and more questionable. Some seem to be just promotion of below average constructions, not honest review's any more.
Today crossover parts and damping materials are often more expensive than the very good, high class drivers in those builds. No research, just relabeling of industry parts "for audio", justify prices that are tenfold the regular sales price. Of course, these sellers of audio products can spend huge amounts on advertising.
This world sucks.
Why should you care because some people have extra funds to spend on boutique components,
which are luxury items anyway? Are they hungry or in a Geldnot?
which are luxury items anyway? Are they hungry or in a Geldnot?
I can confirm that Hawaphon is a very capable damping material, I once built a pair of two-way speakers using that stuff and you can easily test its effecrtiveness with the knuckle test. And yes - you would have to hit heavily. And noone is saying that you shouldn't combine it with reasonable bracing.
And one more hint: Don't buy that stuff from suppliers for speaker-building. Get it from carpentry suppliers.
Regards
Charles
And one more hint: Don't buy that stuff from suppliers for speaker-building. Get it from carpentry suppliers.
Regards
Charles
Energy storage is not the problem. If it were that simple you could fix it by reducing the drive signal until the overall output was flat again and the temporal issues would go away.
What makes a panel resonance non-reversible, and hence a problem is the delay and directivity associated with it's output as a source.
The overpriced boutique parts in speaker building are not bad in itself. Naive children like sweets wrapped in expensive, colorfull and shiny paper, even if they taste worse than Granny's home made candy.
What makes them problematic is the effect they have on DIYS speaker building. If today someone has the idea to starts in that DIYS area, he is distracted from the important facts and repelled from the high cost for a simple speaker. Drivers are as good and cheap as never before. It should be a DIYS paradise and any one able and interested should build speakers. There is just a catch: The cheaper the drivers are, the more crossover parts are needed to make them linear. It is not the exception that accessories make up more than half the price of such a project. Which makes DIYS too expensive for the typical starter, a young person. Why build it your self if a cheap, ready made speaker is less expensive than a beginner project?
When I started with serious speaker building about 40 years ago, crossover parts were about 10-20% of the chassis price. The parts are still identical: Coils, capacitors, resistors. Only difference, today these are produced much cheaper than in the 80's , while having lower tollerance.
The internet, this forum included, instead of explaining why more expensive materials and 70 year old construction technique do not make better electronic components, is full of people telling you that Gold, silver, paper and bees wax are the magic way to audio nirvana.
Influencer get huge boxes of "samples" for free, with retail prices of thousands of €. No problem for Mundorf and the like, with a part that has production cost of 1€ and a retail price of 59€. You can buy any influencer, after some succesfull content they all ask them selves why not get back some of the costs involved or maybe earn just a little. So 99.9 percent of information about crossover components and speaker DIYS is commercial rubbish.
This doesn't help speaker DIYS, but is making it become a niche theme. The few print publications are already dying slowly.
What makes them problematic is the effect they have on DIYS speaker building. If today someone has the idea to starts in that DIYS area, he is distracted from the important facts and repelled from the high cost for a simple speaker. Drivers are as good and cheap as never before. It should be a DIYS paradise and any one able and interested should build speakers. There is just a catch: The cheaper the drivers are, the more crossover parts are needed to make them linear. It is not the exception that accessories make up more than half the price of such a project. Which makes DIYS too expensive for the typical starter, a young person. Why build it your self if a cheap, ready made speaker is less expensive than a beginner project?
When I started with serious speaker building about 40 years ago, crossover parts were about 10-20% of the chassis price. The parts are still identical: Coils, capacitors, resistors. Only difference, today these are produced much cheaper than in the 80's , while having lower tollerance.
The internet, this forum included, instead of explaining why more expensive materials and 70 year old construction technique do not make better electronic components, is full of people telling you that Gold, silver, paper and bees wax are the magic way to audio nirvana.
Influencer get huge boxes of "samples" for free, with retail prices of thousands of €. No problem for Mundorf and the like, with a part that has production cost of 1€ and a retail price of 59€. You can buy any influencer, after some succesfull content they all ask them selves why not get back some of the costs involved or maybe earn just a little. So 99.9 percent of information about crossover components and speaker DIYS is commercial rubbish.
This doesn't help speaker DIYS, but is making it become a niche theme. The few print publications are already dying slowly.