Radiant Acoustics Clarity 66 Speaker Review

[Lars Risbo]

First, THANK YOU for sharing so much valuable information about the design choices you have made. Yes, I've been taking notes!

So please do not feel obligated to share anything in this area: Are there particular measurements that you look to as predictive of spatial quality?

thank you!

Difficult question. My impression is that the magnetic hysteresis distortion is affecting the spatial perception to a surprisingly high degree.

 

[Matt_Holland]

thank you!

Difficult question. My impression is that the magnetic hysteresis distortion is affecting the spatial perception to a surprisingly high degree.

Wow, what an insight.
Would you be ok to elaborate?

Edited to add:
I’m reading your tech blog currently to catch up.

 

[mrick39]

To expand a bit on this, distorted deep bass often sounds "richer" or "fuller" because distortion creates higher harmonics easier to hear than truly deep bass. And of course higher harmonics of low bass notes sound louder to us (see loudness curves) so again the music may sound "better" even though it is more distorted.

That same effect could be EQ'd in then for low distortion systems?

 

[DonH56]

That same effect could be EQ'd in then for low distortion systems?

You could add a boost but it is not the same as adding harmonically-related content to the signal. EQ will boost everything equally.

 

[lewdish]

Jeez that port is a cannon. I'm preferring these slightly brighter out of the box responses where its slightly bright on purpose cause most people will never point speakers at them directly. This lets more people have a more aesthetically pleasing space by placing them forward in most instances and you can listen to the off axis and get the more reference target response

 

[mrick39]

You could add a boost but it is not the same as adding harmonically-related content to the signal. EQ will boost everything equally.

Makes sense, thank you for your response. It's hard for me at times (non-engineer but interested in music, loudspeaker design/engineering, diy speakers etc.) to wrap my head around the fact that some types/levels of distortion can in some situations actually add pleasing or helpful content to the sound we hear from a system.

 

[DonH56]

Makes sense, thank you for your response. It's hard for me at times (non-engineer but interested in music, loudspeaker design/engineering, diy speakers etc.) to wrap my head around the fact that some types/levels of distortion can in some situations actually add pleasing or helpful content to the sound we hear from a system.

NP. A flute is almost a pure tone, whereas most other instruments have additional harmonic content that makes them sound "fuller" or "richer". Same idea with your sound system, except that it is adding more harmonics (plus non-harmonic intermodulation distortion) on top of whatever is in the recording i.e. distortion. In the case of subwoofers, higher harmonics are often easier for us to hear than the fundamental (look up equal loudness curves), so it is louder and "richer" even though "wrong" (inaccurate). I prefer my system get it right, with as low as distortion as possible, so I can hear what the artist and producer intended then add my own coloration (e.g. EQ) if desired (and thus know I am adding it instead of having it forced upon me).

 

[Neadych]

Maybe just maybe reliability and modularity (and not just performance alone) are still the concerns to people spending their money.

For the money people spend on passive components, you could easily have a spare pair of active speakers.

 

[see_no_evil]

For the money people spend on passive components, you could easily have a spare pair of active speakers.

Not great for the environment. Also most people don't spend massive amounts on audio in general, only some do.

 

[eliash]

During the sweeps, I only heard some deep bass distortion at 101 dBSPL. Below it sounded very clean.

View attachment 547419

Waterfall shows a couple of resonances:
View attachment 547421

The 300 to 500 Hz was visisible in on axis response.

Yes, it has kind of a cliff that sets in at 101 dBSPL but below that, it likely beats any speaker its size and by wide margin.

Listened to it yesterday, no flaws from my perspective.

Liked the limited vertical radiation, which fits to my "hut type" listening room.
Bass sounded "slim" initially, but very clean...think I am used to much higher distortion and really appreciated it after a while.

What worries me a bit is this 300Hz resonance in the measurements above. Reminds me of the former rattling crossover boards in my Dynaudios.
(Same 2-way concept - kicked them out(side) and installed a massive steel bar instead, which improved bass attack a lot...also no rattling anymore)

Anyway, the intrinsic weight, the stand and the Alu-baffle improve mechanical jitter certainly a lot (resulting in less rough- and harshness), which was a significant problem of the Dynaudios (weighing less than half before mech mods)...maybe buy them...

 

[Neadych]

I conducted a test in a 4 x 5 x 2.7 m room. I played pink noise from a smartphone and measured the A-weighted levels using a sound level meter (CEM DT-805).
1 m – 71 dB; 2 m – 68 dB; 3 m – 66 dB; 4 m – 64 dB.

It is more complicated, not a simple decay in a “small room”.

View attachment 547963View attachment 547964View attachment 547965
[Acoustics of Small rooms. Kleiner, Tichy]

 

[owner3]

The vertical on this is a complete mess.

 

[henz]

Sitting down to listen will solve most of that

 

[Space is the place]

Listened to it yesterday, no flaws from my perspective.

Liked the limited vertical radiation, which fits to my "hut type" listening room.
Bass sounded "slim" initially, but very clean...think I am used to much higher distortion and really appreciated it after a while.

What worries me a bit is this 300Hz resonance in the measurements above. Reminds me of the former rattling crossover boards in my Dynaudios.
(Same 2-way concept - kicked them out(side) and installed a massive steel bar instead, which improved bass attack a lot...also no rattling anymore)

Anyway, the intrinsic weight, the stand and the Alu-baffle improve mechanical jitter certainly a lot (resulting in less rough- and harshness), which was a significant problem of the Dynaudios (weighing less than half before mech mods)...maybe buy them...

Eliash, what other references do you have to compare to the 66s other than the Dynaudios?
Interesting that you said in room bass response felt "slim" was this Room perfect or other Eq applied? Perhaps the danger of a speaker like this with such low distortion in the bass (and relatively small woofers) is you keep turning it up until it feels like your getting the impact of a speaker with more distortion in the bass.

 

[eliash]

Eliash, what other references do you have to compare to the 66s other than the Dynaudios?
Interesting that you said in room bass response felt "slim" was this Room perfect or other Eq applied? Perhaps the danger of a speaker like this with such low distortion in the bass (and relatively small woofers) is you keep turning it up until it feels like your getting the impact of a speaker with more distortion in the bass.

Basically the Dynaudios are my main listening source. As a reference I use my Stax L700 to judge sound deviations.
Also due to the high double tilted roof/wall down to the floor, there is a lot of bass amplification. It needs all tricks to cope with the room resonances and reflections...but still avoiding digital room EQ.
I listend to the Radiants in a larger HiFi studio, they were positioned close to the back wall. No room EQ applied, they assured. Having certainly less bass amplification there, compared to my room, bass sounded rather flat, but I guess some effect was due to lower harmonic distortion. Addionally I have to state that I don't like fat bass at all, so this rather flat impression wasn't bad, but unexpected and after all nice and clean. Wonder how they will sound at home?

My rooms fundamental resonance is slightly above 30Hz, so I had to tune the Dynaudios (similar port tuning freq.) down a bit by extending the port by some cm (with all the port noise issues) to move both peaks apart. Otherwise much too much stage noise. This will be probably the crucial point whether the Radiants would play nicely at home. Certainly no port tuning possible other than damping it, which I don't like at all soundwise.

 

[markstein]

It needs all tricks to cope with the room resonances and reflections...but still avoiding digital room EQ.

My rooms fundamental resonance is slightly above 30Hz, so I had to tune the Dynaudios (similar port tuning freq.) down a bit by extending the port by some cm (with all the port noise issues) to move both peaks apart. Otherwise much too much stage noise.

Certainly no port tuning possible other than damping it, which I don't like at all soundwise.

Why not just apply some digital PEQ to tame your room modes? Much easier than modifying a ported loudspeaker.

 

[Space is the place]

Eliash, I have a pair of small active Dynaudio's BM5A II, rear ported, that were repaired and brought back to life a couple a weeks ago after sitting dormant for about 8 years! Although they are a "monitor" type speaker they are fairly rich sounding in the low end, although this can be adjusted with switches on the back, They have their limitations (in a bigger room), but i was very surprised just how enjoyable they are to listen to and how they transparent they are, much better than i remember them being.

What intrigues me about the 66 is the relative size of them for the output they produce, I've been thinking about getting larger speakers for my the living room, but having lived with large-ish JBLs and NHT speakers, a larger speakers tend to dominate the room, if i can get a "pint in a half pint pot" regarding size, naturalness, accurate timbre and fairly life like dynamics of larger speaker it's something id like to investigate.

 

[Neadych]

Вы можете приподнять меньшие колонки, наклонить их или перевернуть большие вверх дном.
Акустическая ось должна быть направлена к вашим ушам — это главное.

For obvious reasons. The tweeter on Salon 2 is near 6 feet off the ground. The Genelec is good 2 to 3 feet lower than it so projects a smaller (vertical) image. You can to extremes and listen to 7 or 8 foot tall speakers as I have at shows. You have signers that now seem to be the size of monsters!

You can raise the smaller speakers, tilt them, or flip the larger ones upside down.
The acoustic axis needs to be aimed at your ears—that’s what matters.

 

[eliash]

Why not just apply some digital PEQ to tame your room modes? Much easier than modifying a ported loudspeaker.

When listening to Vinyl, everything still stays analogue flat in my setup today...just a personal challenge and preference. Higher room mode excitation adjusted to critical musical notes by fine positioning the speakers.

...I could eventually go for more analogue hi-end filters (e.g. parametric ones) like for HP crossfeed and Vinyl rumble, which I designed and operate already with my T+A P1260 preamp (via audio processor loopback port), or another hi-end quality solution using a RME ADI with digital filters for Vinyl and room processing, but all in one digital domain, skipping the T+A preamp...

 

[markstein]

When listening to Vinyl, everything still stays analogue flat in my setup today...just a personal challenge and preference. Higher room mode excitation adjusted to critical musical notes by fine positioning the speakers.

...I could eventually go for more analogue hi-end filters (e.g. parametric ones) like for HP crossfeed and Vinyl rumble, which I designed and operate already with my T+A P1260 preamp (via audio processor loopback port), or another hi-end quality solution using a RME ADI with digital filters for Vinyl and room processing, but all in one digital domain, skipping the T+A preamp...

Okay, understood.

Staying analog IMO is nostalgia without any added value, however, with additional complications which could be relatively easy corrected with proper DSP. I am using a Waxwing phono preamp and full digital signal flow - works and sound great!