Radiant Acoustics Clarity 6.2 - Purifi based compact speaker

[jaakkopetteri]

Holy crap, seems like easily the lowest HD tested so far? Probably not an audible benefit in most use, but impressive nevertheless

 

[harkpabst]

Hi everyone
Erin was so kind as to help us investigate the distortion peaks on his measurements that has caused some debate.

It turns out it was a really practical issue; the aluminum backplate on Erin's early samples was slightly loose and rattled a bit as a consequence. I don't believe this should be an issue for any of the products sold as we have improved upon the mass production assembly quite a bit since.

Here's his description of the issue and his new measurements:

I figured it out! Turns out it was coming from the crossover. I let my test run 32x while I listened to the speaker up close. I noticed a resonance that I wasn't sure where it came from so I blocked the tweeter from playing using some cardboard and foam so I could focus on the panels. I then ran the sweeps again and I was able to isolate the sound as coming from the back of the speaker and when I pressed in on the crossover it stopped. So, I used my torx bit to check the tightness and noticed some bolts weren't as snug as they ought to be. I tightened each of the bolts (using the cross-tightening method), re-ran the sweeps and I couldn't hear the noise anymore. I removed the foam/cardboard from the tweeter and ran the test again and these are the results I obtained:



View attachment 402220View attachment 402221

Good to know, indeed.

Might be helpful to post a max. torque for tightening theses screws. Right now, about every customer reading this will be heading to their toolbox.

Overtightening the screws is probably not a good idea either. If they go into T-nuts it might be possible to damage the MDF.

 

[yys310]

Hi everyone
Erin was so kind as to help us investigate the distortion peaks on his measurements that has caused some debate.

It turns out it was a really practical issue; the aluminum backplate on Erin's early samples was slightly loose and rattled a bit as a consequence. I don't believe this should be an issue for any of the products sold as we have improved upon the mass production assembly quite a bit since.

Congratulations!
How do you find out that's something is moving?
When the distortion behavior is asked on Purifi's group I saw Lars and another member said it's 2nd harmonic dominate, something is moving.
Anyone know the mechanism behind?

 

[yys310]

I understand and even it don´t translate to the measurements it´s still strange using such nice drivers while cheaping out on this stuff inside. For 50€/speaker more all this would be nicely covered.

What do you mean by "it don´t translate to the measurements" ?

 

[henz]

Good to know, indeed.

Might be helpful to post a max. torque for tightening theses screws. Right now, about every customer reading this will be heading to their toolbox.

Overtightening the screws is probably not a good idea either. If they go into T-nuts it might be possible to damage the MDF.

I don’t believe this should be an issue on any of the speakers we have sold but I get what you mean! I’ll check with production tomorrow and post their answer here

 

[Ropeburn]

Good to know, indeed.

Might be helpful to post a max. torque for tightening theses screws. Right now, about every customer reading this will be heading to their toolbox.

Overtightening the screws is probably not a good idea either. If they go into T-nuts it might be possible to damage the MDF.

I'll go ahead and claim "average hand force will suffice". I'm aware it's a rather arbitrary figure, but anyone who tends to severely overdo it has no business tinkering with expensive loudspeakers.

 

[kharan]

average hand force + loctite is the way

 

[henz]

This is very nice to know, and excellent news.

Do you know if that also translates into the multitone distortion figures, which were good for a speaker its size but not excellent?

Erin was kind enough to update this measurement as well. It does look better yeah, especially around 300 Hz.

 

[kharan]

Erin was kind enough to update this measurement as well. It does look better yeah, especially around 300 Hz.

Comparing it with the video review now, it does! Nice.

 

[henz]

Good to know, indeed.

Might be helpful to post a max. torque for tightening theses screws. Right now, about every customer reading this will be heading to their toolbox.

Overtightening the screws is probably not a good idea either. If they go into T-nuts it might be possible to damage the MDF.

For reference: we tigthen the screws in the backplate with a torque of approximately 1.0 Newton Meter. (equivalent to approx. setting 11 on a Makita screwdriver)

 

[harkpabst]

How do these compare to the Ascend Sierra LX? Seems like very similar performance but the Ascend have a slightly flatter FR and cost 1/3 what these do?

Is that your company?

At a first glance these speakers have about nothing in common, except being 2-way speakers.

 

[Penelinfi]

I'm guessing the radiance will be a little better in all areas. Of course, you're not going to get 3x better performance. I guess we'd have to wait to see if anyone prefers one or the other subjectively.

 

[gfinlays]

Like I said not my experience so I can´t comment but only referring to Humble Homemade HiFi.

Once upon a time I believed in Tony Gee's (HHM HiFi) capacitor mutterings. Then I found ASR.

All of his tests were uncontrolled and sighted and therfore completely worthless. More recent yest and measurement data clearly shows that with very few exceptions, different capacitors don't sound different.

 

[dfuller]

Holy crap, seems like easily the lowest HD tested so far? Probably not an audible benefit in most use, but impressive nevertheless

Lowest, no - but certainly excellent! I don't think you could ask for better from a 6.5" two-way. Only large 3-ways are really outdoing it - e.g. KH420 at 86dB has midrange distortion so low it's literally falling off the chart, but that's a 3-way speaker with one of the best midrange drivers anywhere (only Purifi's mid and other high end midrange domes match it in that department).

 

[Vos]

Once upon a time I believed in Tony Gee's (HHM HiFi) capacitor mutterings. Then I found ASR.

All of his tests were uncontrolled and sighted and therfore completely worthless. More recent yest and measurement data clearly shows that with very few exceptions, different capacitors don't sound different.

So everything (dacs, cables, capacitors, ...) that measures the same will sound the same?

I´m not a ´cable guy´ but if we are honest, who is connecting these speakers to their amp with the same 0,25€/m quality cable as used internal here?
Same with capacitors, so all´high-end' speaker builders (DIY + manufacturers) could rely 100% on these Bennic caps and all further expenses on pricier parts are a waste of time and money?

 

[Penelinfi]

There may be other things to consider, such as tolerance and matching, voltage ratings or build quality.
I do wonder if some of those exotic caps would measure differently as they seem to "tune" them with certain sound characteristics, at least as they say.
Someone still has to design them using some sort of science, chemistry and maths right?

 

[gfinlays]

So everything (dacs, cables, capacitors, ...) that measures the same will sound the same?

I´m not a ´cable guy´ but if we are honest, who is connecting these speakers to their amp with the same 0,25€/m quality cable as used internal here?
Same with capacitors, so all´high-end' speaker builders (DIY + manufacturers) could rely 100% on these Bennic caps and all further expenses on pricier parts are a waste of time and money?

Yup, if it measures the same, it'll sound the same. Measurement instruments go far beyond the limits of human hearing.

You don't need fancy cables. Sufficiently low resistance, capacitance and inductance such that any measureable (or calculated, the mathematics of impedance calculation is quite simple) difference the cable may make is below the threshold of human hearing. Capacitance has to be ridiculously high to be in any way significant relative to speaker impedance, inductance less so, but still has to be significant.

My speakers are wired with Canare 4S11 starquad. Left speaker, 3.8m long, resistance of 0.0342 Ω, inductance of 0.5 μH, capacitance of 537.4 pF. Right speaker 2.4 m long, resistance of 0.0216 Ω, inductance of 0.3 μH, capacitance of 323.7 pF. It costs about $10/m and when used properly, each pair has a CSA of 4.3 mm² ~11 AWG. The impedance of the cables is negligible compared to the speakers.

Internal speaker wiring is so short, provided it's of sufficient gauge, price per metre is irrelevant.

Decently made film caps are essentially all the same and will measure and perform the same.

Claims made by "High-end" manufacturers are just that. It's pure marketing with no foundation in science.

A lot of DIYers buy into the hype too. None of them do proper measurements or properly controlled blind listening tests to really objectively test their beliefs.

People worry about tolerances of components - film cap tolerances are perfectly adequate and usually exceed the manufacturer's specification by a comfortable margin. Speaker drive unit tolerances are generally considerably worse. Unit to unit variation can seem quite significant, though in practice, from an audibility perspective, it's still nothing to worry about.

Intersting thread with a link to some proper manufacturer data on harmonic distortion figures for aluminium electrolytics:

Würth Elektronik ANP125 - Capacitors don’t cause any appreciable signal distortion

Würth Elektronik’s new Application Note ANP125 publishes the results of a study “The acoustic effects of harmonic distortion of aluminum electrolytic capacitors” on harmonic distortion of electrolytic capacitors. The result: Capacitors don’t cause any appreciable signal distortion. The...

www.audiosciencereview.com

And another thread here examining capacitor differences:

Audible difference in high-end capacitors? - ABX samples

As announced long ago the last part on the subject of audibility of capacitor upgrade in crossovers. The comparison ranges from a very cheap, decades-old film capacitor to an expensive high-end capacitor. As promised, this time there are short audio samples of each capacitor (in a simple...

www.audiosciencereview.com

 

[jaakkopetteri]

Lowest, no - but certainly excellent! I don't think you could ask for better from a 6.5" two-way. Only large 3-ways are really outdoing it - e.g. KH420 at 86dB has midrange distortion so low it's literally falling off the chart

Not sure what you mean, the KH420 has way more HD than the Radiant, at least in the bass region?

 

[kharan]

Not sure what you mean, the KH420 has way more HD than the Radiant, at least in the bass region?

I haven't checked though this is likely to be true, the Clarity 6.5 have astonishingly low harmonic distortion.

Still, it's a two way, whereas the 420 is a three way. Amir doesn't measure IMD, but having a different driver handle bass means the mid driver doesn't have to contend with the IMD from producing bass. I have zero doubt that IMD is lower on the 420. I don't know at which volume level this becomes audible though.

 

[dfuller]

Not sure what you mean, the KH420 has way more HD than the Radiant, at least in the bass region?

In the bass region, sure - I said midrange though.

(It's worth noting that IMD is for sure higher on this, solely by virtue of being a 2 way, but it's still quite good here...)