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Introducing Directiva - An ASR open source platform speaker project

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Rick Sykora

Rick Sykora

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That's cool to hear!

I just meant it that the driver would have enough displacement (a la Dutch & Dutch 8C) and can still be crossed around ~2KHz so there is no need for larger tweeters with waveguides.

Ofcourse there will always be need for a crossover somewhere because from what I collected the excursion needed would be insane below 100Hz anyway.

If we were making an 8c clone, agree this new Purifi driver might be worth considering. Still do not know a price for it and would have to be cheaper than a SB15 + decent woofer to be considered. Not sure the SB15 alone may not work for some folks, but since Tim already hinted, we are working on a larger version of the initial prototype that would have more bass extension.

This may mean that bass module aspect may wait, but also means we would have something more interesting for Amir to test.:)
 
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Rick Sykora

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Curious what prompted that.
Presumably you were all using REW previously?

Primarily more consistent and accurate results across the team is the goal.

If you want more specifics, I discuss in the r2 prototype thread.
 

fluid

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I just meant it that the driver would have enough displacement (a la Dutch & Dutch 8C) and can still be crossed around ~2KHz so there is no need for larger tweeters with waveguides.
The directivity of an 8” driver at 2 K is a bit narrower than a 5 or 6 inch driver and would not be a great match for the DXT.
 

muad

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Has anyone started work on the bass module yet? I'm looking to start building one, and was curious to see what people have come up with.
 
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Rick Sykora

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Has anyone started work on the bass module yet? I'm looking to start building one, and was curious to see what people have come up with.
Since the monitor became a larger, 3-way design, the bass module as delayed to determine how its design might need to be modified. We are stilling evaluating potential drivers but have encountered into some availability issues. I have already designed a couple for other applications. If you cannot wait, may be able to offer something in the interim but would need to know your goals.
 

muad

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Thanks Rick!

I'm not going to continue in this thread to keep it on track. I created a new topic

 
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Rick Sykora

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Hi folks!

I regret the lull here, but the Directiva r2 lead has a family issue and so the project is delayed. We are hoping his situation is resolved over the summer, but it is not clear. I meant to post and update everyone sooner but have been quite busy with Buckeye Amp testing and another ASR potential project. I expect we will be revealing the project soon but is up to Amir. :)

The primary r2 woofer has been narrowed down to the Wavecor SW182BD03. Wavecor has many variants of this design and provides some flexibility for the bass module. Availability is still challenging but better than our secondary choices currently. I still have some measurement rig challenges to address but as soon as time allows, expect to prototype a bigger r2 cabinet.

Stay tuned and thanks for your patience!

Rick
 

abdo123

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After Erin revealed that the wide directivity speaker in his binaural comparison thing on his Youtube channel is the Philharmonic BMR (which basically have flawless ERDI but very wide) I'm very very excited to see this project go through.

The BMR sounded really off to me, and I'm now a firm believer that all reflections are a spawn of the devil that need to be eliminated at all cost.
 
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Rick Sykora

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After Erin revealed that the wide directivity speaker in his binaural comparison thing on his Youtube channel is the Philharmonic BMR (which basically have flawless ERDI but very wide) I'm very very excited to see this project go through.

The BMR sounded really off to me, and I'm now a firm believer that all reflections are a spawn of the devil that need to be eliminated at all cost.
Binaural speaker auditioning seems be getting some traction lately, but is still fraught with challenges. Would really need to experience a speaker I know well to gauge its promise. Right now it seems like a gimmick to me. But this is a topic for another thread…

Have not heard the BMRs, but they clearly have a distinct sound signature. Certainly they have the potential to cause more reflections in a room that is reflective. To judge them via headphones without a controlled baseline in a room that may not represent my own using a binaural recording system seems convoluted to me. Am not a big headphone user either though. I would be more interested in trying a binaural comparison with a beolab or other speaker that allows directivity to be configured. Have you heard something like the beolab yet?
 
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Binaural speaker auditioning seems be getting some traction lately, but is still fraught with challenges. Would really need to experience a speaker I know well to gauge its promise. Right now it seems like a gimmick to me. But this is a topic for another thread…

Have not heard the BMRs, but they clearly have a distinct sound signature. Certainly they have the potential to cause more reflections in a room that is reflective. To judge them via headphones without a controlled baseline in a room that may not represent my own using a binaural recording system seems convoluted to me. Am not a big headphone user either though. I would be more interested in trying a binaural comparison with a beolab or other speaker that allows directivity to be configured. Have you heard something like the beolab yet?
 

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Binaural speaker auditioning seems be getting some traction lately, but is still fraught with challenges. Would really need to experience a speaker I know well to gauge its promise. Right now it seems like a gimmick to me. But this is a topic for another thread…

Have not heard the BMRs, but they clearly have a distinct sound signature. Certainly they have the potential to cause more reflections in a room that is reflective. To judge them via headphones without a controlled baseline in a room that may not represent my own using a binaural recording system seems convoluted to me. Am not a big headphone user either though. I would be more interested in trying a binaural comparison with a beolab or other speaker that allows directivity to be configured. Have you heard something like the beolab yet?
Erin had all the in-room responses EQ-ed (to some target i believe) and it was in his heavily treated home cinema room (any sort of recording in a reverberant room sounds awful tbh) so it’s likely that in a real life scenario (no EQ, no treatment) they would sound even worse under blind conditions.

But yeah I understand that binaural recordings could potentially sound extra bad than a real life experience because you’re not feeding your brain the visual cues of the room as well but at the same time it’s so difficult to ignore how bad the BMRs sounded. While the waveguided speakers just sounded the same lol.

The Beolab would be an awesome experience indeed if they were still produced, or within my pay grade.
 
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chych7

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My own experience with the BMRs puts it far ahead in terms of soundstaging and imaging than some dome (Polk) and horn (Klipsch) speakers I've tested in the same room. My room is probably more treated than Erin's room though (based on pics of his room from what I recall), with all early reflection points well-absorbed (including ceiling). I do notice significant sensitivity to the room treatments and imaging precision with the BMRs; if I remove a panel or two, the imaging shifts/degrades very readily. If you can treat early reflection points well, then you can get both excellent imaging and soundstage with the BMRs; narrow directivity speakers would inherently have a soundstage disadvantage.
 

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Erin had all the in-room responses EQ-ed (to some target i believe) and it was in his heavily treated home cinema room (any sort of recording in a reverberant room sounds awful tbh) so it’s likely that in a real life scenario (no EQ, no treatment) they would sound even worse under blind conditions.

But yeah I understand that binaural recordings could potentially sound extra bad than a real life experience because you’re not feeding your brain the visual cues of the room as well but at the same time it’s so difficult to ignore how bad the BMRs sounded. While the waveguided speakers just sounded the same lol.

The Beolab would be an awesome experience indeed if they were still produced, or within my pay grade.

I would not call Erin's home theater heavily-treated. He has carpet, 3 sound panels per side wall, and some foam on the front wall behind the curtain, in a huge room, IIRC. I call that light to moderate treatment.

I own BMRs and recently swapped them out with narrower R3s. When I listened to the binaural recording with headphones, I did not think it represented the in-room sound of the BMRs accurately. (Not intending to knock Erin's work here!) What you hear in-room is very spacious, but somewhat diffuse. It makes you sit up and take notice in a good way. Over time, you start to wonder if they are lighting up the side walls a bit too much and "smearing" a bit due to all the reflections. Swapping to a narrow dispersion speaker tells the story, but the difference is nowhere near as stark as it is in Erin's recordings.

Having said that, his recording methodology could prove to be a very useful tool to some people in some circumstances.
 

abdo123

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I would not call Erin's home theater heavily-treated. He has carpet, 3 sound panels per side wall, and some foam on the front wall behind the curtain, in a huge room, IIRC. I call that light to moderate treatment.

I own BMRs and recently swapped them out with narrower R3s. When I listened to the binaural recording with headphones, I did not think it represented the in-room sound of the BMRs accurately. (Not intending to knock Erin's work here!) What you hear in-room is very spacious, but somewhat diffuse. It makes you sit up and take notice in a good way. Over time, you start to wonder if they are lighting up the side walls a bit too much and "smearing" a bit due to all the reflections. Swapping to a narrow dispersion speaker tells the story, but the difference is nowhere near as stark as it is in Erin's recordings.

Having said that, his recording methodology could prove to be a very useful tool to some people in some circumstances.

We’re talking about domestic settings here not anechoic rooms. Anyone with an entire wall made of absorption is definitely in the heavily treated side of the spectrum for me.

Also the BMR is incredibly narrow vertically, so theoretically all what Erin needed was the panels on the side walls.
 

chych7

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You can see his room at the end of his original BMR review:

A few bass traps and 6 sidewall absorbers out of 2" Roxul 60, which absorbs well over 250 Hz (reference). If the absorbers were working as intended, how would that explain the difference in sound? Or perhaps the front wall reflection is at play. The BMR dispersion is so wide that it's radiating an appreciable amount of sound even behind the speaker.
 
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abdo123

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You can see his room at the end of his original BMR review:

A few bass traps and 6 sidewall absorbers out of 2" Roxul 60, which absorbs well over 250 Hz (reference). If the absorbers were working as intended, how would that explain the difference in sound? Or perhaps the front wall reflection is at play. The BMR dispersion is so wide that it's radiating an appreciable amount of sound even behind the speaker.
The wall behind the speakers is made of foam, it’s a fake wall. So that’s hardly the issue in my opinion.
 

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I would have preferred if the speakers were to have been EQ'd to a similar on-axis/listening window. EQ'ing to a certain in-room target with speakers of varying directivity will have a severe influence on the direct sound. I'm curious what filters were used on speaker B (the BMR) to achieve the in-room response and what the effect would be when we superimpose it on the anechoic data. It's hard for me to focus on the spacial qualities because there is a clear difference in spectral balance.
 

Chromatischism

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After Erin revealed that the wide directivity speaker in his binaural comparison thing on his Youtube channel is the Philharmonic BMR (which basically have flawless ERDI but very wide) I'm very very excited to see this project go through.

The BMR sounded really off to me, and I'm now a firm believer that all reflections are a spawn of the devil that need to be eliminated at all cost.
The BMR is designed to imitate a live space such as a performance hall. I haven't had a chance to hear them though, and I have no idea how well it translates through a recorded test.

If you like a more clear, intimate sound, you may prefer controlled directivity.
 

abdo123

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I would have preferred if the speakers were to have been EQ'd to a similar on-axis/listening window. EQ'ing to a certain in-room target with speakers of varying directivity will have a severe influence on the direct sound. I'm curious what filters were used on speaker B (the BMR) to achieve the in-room response and what the effect would be when we superimpose it on the anechoic data. It's hard for me to focus on the spacial qualities because there is a clear difference in spectral balance.
I don’t think a microphone can tell what is direct sound and what is reflections like the human brain does. So there is no point in maintaining direct sound imo. We’re hearing the sum that is arriving at the microphone anyway.
 
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