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ASR Directiva Open Source Speaker Review

xyvyx

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I don't think the DI would be as smooth with the Bliesma or Peerless, but it might be acceptable. That DA32 is a serious tweeter for the money.
Yup, when I saw the graphs for it a long while back, I thought it might be a great fit...

I should receive my SB radiators in a week or two at which point I can get this project buttoned-up & start with the tuning!

(I just discovered the Directiva project a few days ago. It changed my mind to try the passive radiator vs. the ridiculously long ported configuration I was shooting for.)

I might try this out w/ the new balanced miniDSP Flex + my NC252 Buckeye amp.
 

Ro808

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The sound was very clean, making me want to really crank up the volume. When I pushed that hard, I could sometimes hear a bit of ticking sound. I am not sure if the the minidsp was saturating its input or the driver was the issue. By then the volume was pretty loud and with two speakers you would be fine.

Someone may have already noticed this, but the ticking could be coming from the passive radiator.

Did you happen to measure distortion at and above [email protected]?
Yes, I know this is loud, but peaks at such levels are not uncommon in an elongated (home cinema) room or during a party.
 
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Rick Sykora

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Someone may have already noticed this, but the ticking could be coming from the passive radiator.

Did you happen to measure distortion at and above [email protected]?
Yes, I know this is loud, but peaks at such levels are not uncommon in an elongated (home cinema) room or during a party.

Amir checked at 96 dB and other than the equipment issue he mentions, there was no major distortion issue. I have pushed the passive radiator and it tends to have a more polite reaction to overexcursion. If he heard a tick, it was more likely the woofer. The bass tuning does push the woofer more than a commercial design but not beyond most music. As noted, even less likely with 2 speakers. The woofer is not cheap, so if concerned, the HP filter can be adjusted. In a home theater app, this is not an issue as the subwoofer would handle the lower bass.
 

Rick Sykora

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Has anyone identified the frequency of the tick sound?
No indication Amir did and am not inclined to push an expensive woofer to its limits just for curiosity sake. The unit that I got back from Amir was damaged but every indication was that damage happened in shipment. It was an older drive from an SPK5 that had been shipped extensively and that speaker originally arrived damaged to Amir. No other Purifi woofers (I have 6), have a comparable issue.

EDIT…

As the driver in question has a voice coil that is rubbing slightly, it may be it was in the process of failing as Amir was testing. Without independent testing or having a speaker pair to compare, marginal results from defects or damage are omnipresent when the sample size is one.
 
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DualTriode

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Hello Rick,

There is a lot of talk about the Purify 6 1/2 inch woofer in the pages lately.

There appears to be an distortion issue identified at 380hZ.

This distortion peak shows up even in the Purifi factory data.
 

Rick Sykora

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Hello Rick,

There is a lot of talk about the Purify 6 1/2 inch woofer in the pages lately.

There appears to be an distortion issue identified at 380hZ.

This distortion peak shows up even in the Purifi factory data.
Did not show in Amir’s measures. Who is claiming?
 

mdsimon2

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DualTriode

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Did not show in Amir’s measures. Who is claiming?

Oh yes it does.
ASR Directiva Measurement Distortion Open Source Purifi Speaker.png
 

Rick Sykora

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Hello Rick,

There is a lot of talk about the Purify 6 1/2 inch woofer in the pages lately.

There appears to be an distortion issue identified at 380hZ.

This distortion peak shows up even in the Purifi factory data.
Who else is claiming?
 

DualTriode

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Who else is claiming?
Who does not matter, we do not need the personalities that will get wrapped up in it.

look at the distortion plots at the Purifi manufacturers site.

Look at the plots at hificompass, anywhere there is a Purifi distortion plot.

PTT6.5W08-01B-2.png
 

somebodyelse

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Short version: in a deep dive into March's Sointuva some issues turned up. March pointed to sensitivity around driver mounting that had been discussed with Purifi, with a response that purported to be from them saying 'good catch' or words to that effect. A lot of this is floating around as screenshots from other fora because of who can and can't post where and it's turned into something of a bun fight. Some have gone looking to measurements on other speakers using the same driver and spotted peaks of varying heights at the same frequency in most of them, so there does appear to be something going on, but I'm not sure if anyone has managed to demonstrate exactly what yet. The post I linked above suggests it's the magnet mass / basket stiffness issue Linkwitz detailed here.
 

Rick Sykora

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Looked over EAC's THD measurements for Sointuva and Purezza and only Sointuva is showing some narrow Q 3rd harmonic distortion.

I just got my SPK5s retuned (shorter ports) and back together. Will measure one and see what I find. :)
 

samysound

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Looked over EAC's THD measurements for Sointuva and Purezza and only Sointuva is showing some narrow Q 3rd harmonic distortion.

I just got my SPK5s retuned (shorter ports) and back together. Will measure one and see what I find. :)
I believe the directiva review amirm posted also showed ~380hz distortion?
 

Rick Sykora

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I believe the directiva review amirm posted also showed ~380hz distortion?

Yes. but as stated, Amir left equipment on top. Cannot rely on those measurements unfortunately.
 

Rick Sykora

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Solution seems to be simple: brace the magnet.

Based on my quickie check, cannot deny the possibility. Need to test under quieter conditions though.

Given the SPK5 brace goes behind the woofer may be able to try your proposed solution with a bit of work. ;)
 

Rick Sykora

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Who does not matter, we do not need the personalities that will get wrapped up in it.

look at the distortion plots at the Purifi manufacturers site.

Look at the plots at hificompass, anywhere there is a Purifi distortion plot.

View attachment 215584
Could you be more specific about which graph this distortion appears? Am seeing there might indicate an issue closer to 500 Hz but not 380 Hz.

Should also mention that the woofer Amir tested may have been bad or going bad.
 
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Rick Sykora

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Hello Rick,

There is a lot of talk about the Purify 6 1/2 inch woofer in the pages lately.

There appears to be an distortion issue identified at 380hZ.

This distortion peak shows up even in the Purifi factory data.
As these woofers are not inexpensive, I can certainly understand concerns over their performance. That said, it is important to understand the conditions under which any measurements have been done. Given this, here are my findings:
  1. I cannot reproduce Amir's results under any conditions.
  2. I tried measurements with both SPK5 and Directiva r1 and did not get consistent results. I will stress conditions matter greatly. The SPK5 is vented with a crossover mounted internally and the Directiva has a PR in a different. Would expect a Sointuva to have yet another set of results.
  3. In the end, also looked at EAC's and hificompass's test of the driver and found no evidence of a major issue.
Here is the hificompass measure at 2.83 V and 20 mm...
ptt6.5w08-01b_20mm_2v83_hd.png

If you go to the site, you can try higher voltage levels and all are pretty good.

My takeaway is that the Sointuva measures are unique and could be an isolated driver/speaker issue and has some contributing factor for a distortion issue. If Lars was evasive, he may have been avoiding a long, drawn-out discussion. I do not see any repeatable reason for concern at this point.

Hope this helps!

Rick
 
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