Introducing Directiva - An ASR open source platform speaker project

[Rick Sykora]

Ask that we please keep the off-topic discussions (not Directiva) to other threads please as this one is rather long already. Thanks!

I did give the r2 sealed protos a quick listen this morning and like what I heard so far. Not sure what a passive version might look like as would need bigger cabinet to fit the crossover and redesign it without having the advantage of being able to add filters with gain.

 

[Rick Sykora]

Directiva fans,

After a reshuffle of task assignments, am pleased to announce that r2 work has resumed. I have installed the slotted sides on the original prototype, flashed the minidsp and loaded it with our latest active crossover. I am doing some initial check out over the weekend and then will ship to another team member with access to professional measuring equipment to (hopefully) finalize.

Thank you for your patience and plan to post my findings over this weekend.

Kind regards,

Rick

 

[D!sco]

With what little I know about the delay, I just hope the team is doing well and in good spirit.

 

[Rick Sykora]

As promised, I have first round of measurements with r2.

Since it has been a while, minidsp has new software and firmware and so took some time to update, test and then load the prototype crossover design. Initial measurements and the project are posted on the r2 prototype thread.

 

[Behrend]

As promised, I have first round of measurements with r2.

Since it has been a while, minidsp has new software and firmware and so took some time to update, test and then load the prototype crossover design. Initial measurements and the project are posted on the r2 prototype thread.

Awesome!

Link for the lazy:
https://audiosciencereview.com/foru...r2-monitor-prototype-build.30132/post-1789227

 

[mx2]

Getting back to the Directiva journey...

After some more iterations that were trying to use the Denovo cabinet and tradeoffs with the bracing and other extensive modifications, @ctrl proposed a new cabinet. Now known as version 8, it reminded me of the Salk Veritas HT1 (which I happen to like and so we progressed with it). One of the primary questions was about beveling and whether the top of the front baffle needed to be beveled.
View attachment 112921View attachment 112923
View attachment 112924View attachment 112925

If you look at the frequency range of 2-5kHz and compare the versions, you will see that version 9 (top edge beveled) has slightly wider radiation. While this difference is slight, would not have expected the result. Since it is better and a bit less work, the vote goes to version 8.

A couple of side comments. Small differences are a good sign as they suggest you are getting towards a point of diminishing returns. The other note is a shout out to @ctrl for getting us this far this fast. Between expending his effort and computer time, we are much further along than if I had to build and measure all these alternative designs. If that were the case, you likely would not have heard from me until next year and/or would have a less optimal design!

@Rick Sykora thanks for starting this awesome thread. Lots of inspiration! I'm really thinking about building the version 8 cabinet. Do you happen to still have the cabinet dimensions? Don't have a good measuring setup here so let's see how this goes

 

[Rick Sykora]

@Rick Sykora thanks for starting this awesome thread. Lots of inspiration! I'm really thinking about building the version 8 cabinet. Do you happen to still have the cabinet dimensions? Don't have a good measuring setup here so let's see how this goes

Thanks, looked for the drawing and have not found yet. One key computer has a disk problem and am trying to recover. Give me a couple of days.

If not, the design is comparable to r2 but with the larger woofer. Should be able to reproduce if I cannot find.

 

[ctrl]

I'm really thinking about building the version 8 cabinet. Do you happen to still have the cabinet dimensions?

These data come directly from the simulation software and are tight. So, you may need to add a millimeter or two here and there.



// enclosure dimension in mm
widthTop = 135
widthBottom = 240
heightNarrowStart = 200 (see sketch)
height = 406
depth = 260
rounding 25

// driver positions in mm
pos=350
hWoofer = pos-145
hTweeter = pos

 

[Rick Sykora]

Thanks @ctrl, looks as though I never built v8 and so yours are the only drawings. Cannot boot the drive but can access all the files and did not find any other drawings.

 

[mx2]

These data come directly from the simulation software and are tight. So, you may need to add a millimeter or two here and there.

View attachment 356849 View attachment 356848

// enclosure dimension in mm
widthTop = 135
widthBottom = 240
heightNarrowStart = 200 (see sketch)
height = 406
depth = 260
rounding 25

// driver positions in mm
pos=350
hWoofer = pos-145
hTweeter = pos

Thanks @ctrl, looks as though I never built v8 and so yours are the only drawings. Cannot boot the drive but can access all the files and did not find any other drawings.

This is great - thank you both!!

Let's see how it goes...at the rate I work on projects, the next update might be in 5 years

 

[kimmosto]

"Open source" is for softwares. This is diy loudspeaker.

 

[ChargedCapacitor]

"Open source" is for softwares. This is diy loudspeaker.

That is incorrect.

 

[Rick Sykora]

"Open source" is for softwares. This is diy loudspeaker.

Narrowly defined, agree open source is more readily applicable to software. In the context of the Directiva project, all of the “source” information is freely available for anyone to use how they want. This is loosely comparable to open source software. In the software context, there often is some licensing that may further control reuse.

I recently announced another project called Denotiva and specifically stated it would not be open source. Like open source software, I plan to control the intellectual property. In this context however, I plan to provide complete build information but not all the design details (like the driver measurements and other design details).

Hope this helps clarify.

 

[kimmosto]

Terminology mixing is unnecessary. There has been free diy designs and open source softwares available for decades. Very easy to distinguish and no need to mix or make language/terminology more cool or modern. Maybe I'm too old and done too many decades both software and speaker designing.

 

[lewdish]

Terminology mixing is unnecessary. There has been free diy designs and open source softwares available for decades. Very easy to distinguish and no need to mix or make language/terminology more cool or modern. Maybe I'm too old and done too many decades both software and speaker designing.

Its not uncommon to have projects that are free to share and publicly accessible to be defined as open source, it just means theres an origin point for a product and should be credited if its used and modified

 

[mcdn]

That is incorrect.

there are many open source hardware licenses, such as CERN-OHL: https://ohwr.org/cernohl

Open source means you can build the end product from the source information provided, it might be code, it might be design files. But you can take the source and build the object.

 

[TimVG]

Maybe I'm too old and done too many decades both software and speaker designing.

And the community cannot thank you enough for the work you've done, and are still doing. Legend.

 

[kimmosto]

English has quite enough options for avoiding open source (code). For example open diy speaker projects could be "open data" or "open projects" with original measurement data, XO simulation, enclosure+driver simulation, baffle simulation, response merging, data conversion, DSP config files etc. For example, author of VituixCAD says right now that VCAD project files (*.vx*) with measurement data is not a source. Source is the designer of initial project
Ok, this is not a serious problem at all. Repetition of "open source" become annoying when it spread to Speaker reviews... area. Reviews are so poor that everything else should try to improve.

 

[Rick Sykora]

Terminology mixing is unnecessary. There has been free diy designs and open source softwares available for decades. Very easy to distinguish and no need to mix or make language/terminology more cool or modern. Maybe I'm too old and done too many decades both software and speaker designing.

English has quite enough options for avoiding open source (code). For example open diy speaker projects could be "open data" or "open projects" with original measurement data, XO simulation, enclosure+driver simulation, baffle simulation, response merging, data conversion, DSP config files etc. For example, author of VituixCAD says right now that VCAD project files (*.vx*) with measurement data is not a source. Source is the designer of initial project
Ok, this is not a serious problem at all. Repetition of "open source" become annoying when it spread to Speaker reviews... area. Reviews are so poor that everything else should try to improve.

With respect to languages, English is imprecise. But to your point, precision is needed in some cases. Often would emphasize this with technical writers that did not always understand the technical aspect of their effort. As software engineers, precise language is key to good coding. However, some cultures have very precise language but others are not. Once I started working with Asian culture, attained a much greater appreciation for how different their (usually symbolic) languages are. My experience is this difference brings about a broader conceptual mind set.

We are the products of our environment, so really do understand your position. I also appreciate how some prefer ”fuzzier” language than others. Some days I think this is awful and others I wonder how brittle life would be with mathematical precision. For now, that flexibility is what makes humans better than machines…

Back to the topic of speaker design, there is often more than one good design solution. If someone tells me otherwise, can point to some very precise engineering designs that failed due to insistence of “the one right way”. As a fellow older engineer, am pretty sure you appreciate. I was out to dinner with some NASA engineers and one smart wife (who worked at NASA in event management) once told me she knows “many really smart people that entirely lack common sense”.

 

[holdingpants01]

Open source (disambiguation) - Wikipedia

en.wikipedia.org