ASR Directiva Open Source Speaker Review

[Godataloss]

I don't say it in a cynical way, honest question, are all who goes about, do this instead of that, are speaker designers? To whom feels adressed, Don't take it personally and I don't want to offend anyone, but it seem to me that a decent amount of R&D was made to come up with this design, and doesn't feel like the same amount of studying on the task at hand was performed by going with general statements like this. But I may be wrong really, no offense.

This is the same defense that's been dished out for years by the industry behemoths- the dispelling of which is one of the prime directives of this forum. The circle has officially been closed if the Directiva is to be viewed as beyond reproach, lol.

 

[PeteL]

This is the same defense that's been dished out for years by the industry behemoths- the dispelling of which is one of the prime directives of this forum. The circle has officially been closed if the Directiva is to be viewed as beyond reproach, lol.

Thanks, but there was no "defense", that was a simple question. I did not say anywhere neither that the design was without reproach, me I don't know enough to state something like that.

 

[preload]

Now that we’re on page 20, and since the purpose of a loudspeaker is to listen to and enjoy it (as opposed to staring at a printout of its measurements and marveling at the smoothness) has anyone listened to and compared the Directiva to an existing commercial product?

 

[Sancus]

Excellent design exercise, but it kills me a bit to see that driver is capable of 33hz in a slightly larger (.8 ft3) box. The cost of a larger box would likely be offset by using a port tube instead of a PR. Losing the PR also brings in the possibility of the use of plate amps with dsp. 33hz with the same BOM and similar footprint seems like a nobrainer.

Did you read the review? It clearly states: "My understanding is that a traditional port design is difficult for the Purifi driver and hence the use of the radiator."

There's a lot of vague/generic design criticism in the last couple of pages with no work done to ensure they're realistic or good ideas. "just add a port", "just design your own waveguide for a different tweeter", not very reasonable or simple suggestions.

 

[eddantes]

There's a lot of vague/generic design criticism in the last couple of pages with no work done to ensure they're realistic or good ideas. "just add a port", "just design your own waveguide for a different tweeter", not very reasonable or simple suggestions.

Completely agree. What a strange thread! We have measurements that would place this "home built" speaker into the top of the top, and half the thread is complaints about something or other. Didnt realise Kevin Voeks has a bot crew looking out for him!

(That was justa joke... I'm sure KV can write his own flame posts)

(That too was joke...)

 

[sarumbear]

Completely agree. What a strange thread! We have measurements that would place this "home built" speaker into the top of the top, and half the thread is complaints about something or other. Didnt realise Kevin Voeks has a bot crew looking out for him!

(That was justa joke... I'm sure KV can write his own flame posts)

(That too was joke...)

If you don’t know you can’t recognise exquisite work.

If you don’t know you can’t recognise quality.

If you don’t know you can’t imagine how hard the others worked.

If you don’t know you can only criticise.

 

[Chromatischism]

Far easier than with the PR in the rear. Port needs less room to breath. But hell, put it in the bottom of the enclosure and damp with a stand- maybe that would hide it from the Kipple too, lol?

What do you base this on? I just have my experience, and I haven't found the SB Acoustics PR any harder to position near the front wall than a rear-ported speaker. If anything, it's easier. Of course all speakers need equalization when doing so.

 

[fluid]

For those interested in the what if's of ports, dual Purifi passive radiators, waveguides and Bliesma tweeters then have a look at some of Hificompass's projects with the Purifi driver, there is even one with a ribbon. Lots of technical information measurements as well as subjective descriptions.

https://hificompass.com/en/projects/2-way-systems/puri-bliss-bewg

 

[preload]

Completely agree. What a strange thread! We have measurements that would place this "home built" speaker into the top of the top, and half the thread is complaints about something or other.

...and 0 reports of how a speaker that measures "at the top of the top" actually sounds compared to commercially available offerings.

 

[Rick Sykora]

For those interested in the what if's of ports, dual Purifi passive radiators, waveguides and Bliesma tweeters then have a look at some of Hificompass's projects with the Purifi driver, there is even one with a ribbon. Lots of technical information measurements as well as subjective descriptions.

https://hificompass.com/en/projects/2-way-systems/puri-bliss-bewg

Yes, they have some interesting projects, but this has already been discussed more than once in the Introducing Directiva thread and really does not belong in a review thread.

 

[PeteL]

...and 0 reports of how a speaker that measures "at the top of the top" actually sounds compared to commercially available offerings.

Amir gave his listening impressions like he does with every speakers no? Some people also like the preference score for a comparison base.

 

[Rick Sykora]

Amir gave his listening impressions like he does with every speakers no? Some people also like the preference score for a comparison base.

I'll add that it is not Amir's review style to make competitive comparisons AND (as has been pointed out earlier), it is hard to have major competitive comparisons when I only built 2 and we just finished the initial design.

Finally, the goal of Directiva was to see what we could do and there was no goal to meet or exceed some commercial speaker. When some more get built, may have get some comparos. This would be no different than any other product that Amir got as a pre-release sample. Happily, Directiva exceeded expectations.

There is a proposal to have Directiva r1 be part of a blind test in the spring. Am considering, but looks like it might be a better fit for an r2.

 

[fluid]

Yes, they have some interesting projects, but this has already been discussed more than once in the Introducing Directiva thread and really does not belong in a review thread.

I was trying to help point the speculation about possible variants to a place where there is information rather than it continue here. Maybe you would prefer another 5 pages of armchair criticism of your design choices as being more appropriate to a review thread.

 

[Rick Sykora]

I was trying to help point the speculation about possible variants to a place where there is information rather than it continue here. Maybe you would prefer another 5 pages of armchair criticism of your design choices as being more appropriate to a review thread.

Thanks for the thought, but been doing product development for decades. Its rare that you make everyone happy.

So have pretty thick skin when it comes to taking criticism. ASR has lots of smart members who filter out the what-about posts and some pretty decent moderators if thing get really out of control.

 

[Arc Acoustics]

It is not as simple, as just getting a "Better" tweeter. All aspects of tweeters to not move in unison as you go higher in price.

Some aspects will be better, but there will be trade offs in other areas.

Like asking what is the best tweeter.....You will get a dozen answers, but based on what aspects you WANT to be better. There is not one tweeter that does everything better than all the rest.

Well, avoid no good options, which is what I'm saying.
DXT does not have that good directivity compared to properly designed waveguides, does not sound right at least for me, and simply does not match the quality of the woofer.
And if you do have the ability to design the directivity, you have plenty of choices, if you don't, you have only limited options.

Which ones?

Such as D2904/71000*, or even T330 or 2905/970000 oldies sound far better for me.
Of course they're pricier, but it's listenable at least.

 

[preload]

I'll add that it is not Amir's review style to make competitive comparisons AND (as has been pointed out earlier), it is hard to have major competitive comparisons when I only built 2 and we just finished the initial design.

Oh I didn't realize these weren't in wide availability yet. Hope people start building them soon and sharing their impressions! Congrats again.

 

[Tangband]

seems like the SB passive radiator in this case is actually limiting output and probably increasing distortion. Seems counter productive to use such an expensive woofer with low distortion performance and then handicap it with the SB PR. Why not just go all in and use a pair of the Purifi PR

Oh I didn't realize these weren't in wide availability yet. Hope people start building them soon and sharing their impressions! Congrats again.

I have now been reading the whole ” introducing Directiva” thread. Its nice to see that they already have considered SB26adc and other tweeters , and closed box as other alternatives, but found out that it was not good in this project.
Very nice work.

 

[aac]

DXT does not have that good directivity compared to properly designed waveguides, does not sound right at least for me, and simply does not match the quality of the woofer.

One of the points of this was to make it from available parts (hence shelf-available waveguide and box).
If it wasn't I believe it'd be a 3 way instead (or a large 2 way like jbl m2, but no purifi woofer then, so 3 way). Maybe with a smaller 4 inch purifi cone.

 

[Rick Sykora]

Hi,
I assume you went with the SB passive radiator due to cost vs performance trade off? Just curious what the performance trade off is versus using two of the Purifi passive radiators? Would the latter drive distortion even lower? increase max loudness capability significantly?
thanks!

I regret I seem to have missed your question from earlier in the thread...

The short answer is yes regarding price/performance, but more details in the Introducing Directiva thread. I tried the dual Purifi PRs in a fancier cabinet design and did not get far enough to see if the distortion was much better due to resonance issues. They are also much more expensive than the SB. Meaningfully measuring distortion at bass frequencies is not something I (or most hobbyists) are equipped to do. It is useful as a relative measure, but audibility is also less of a concern.

The major bass distortion from a PR is going to be when pushed to excursion limits. The design tuning takes this into consideration.

 

[Tangband]

I regret I seem to have missed your question from earlier in the thread...

The short answer is yes regarding price/performance, but more details in the Introducing Directiva thread. I tried the dual Purifi PRs in a fancier cabinet design and did not get far enough to see if the distortion was much better due to resonance issues. They are also much more expensive than the SB. Meaningfully measuring distortion at bass frequencies is not something I (or most hobbyists) are equipped to do. It is useful as a relative measure, but audibility is also less of a concern.

The major bass distortion from a PR is going to be when pushed to excursion limits. The design tuning takes this into consideration.

With a steep HP filter below the PR:s tuning frequence you can limit the excursion somewhat.