Ascilab C8C Active Speaker Review

[amirm]

For the average person who loves listening to music, is it an advantage or a disadvantage ( disadvantage meaning, it is a bit of a curse) to be a trained listener? Or stated another way, is ignorance bliss in this regard?

If you are going to rely on your ears to select equipment, then it pays to be trained. Otherwise, it is not necessary although one can become sensitized over time.

 

[amirm]

Related experience on my side is occasionally demoing acoustic systems to usually untrained listeners in A/B comparison. No formal listening tests.

In other words, nothing reliable. In such testing you wouldn't even have the ability to control distortion as a variable.

 

[Curvature]

For me the biggest advantage of cardioid speakers is the reduction of front wall reflections. This gives better focus in sound image and avoids notches in the frequency response due to cancellation by reflected sound.

Genelec 8361A comes close due to large size but still has considerably more sound leaking to the rear side below 2kHz than the Orbits. Due to the rear port, it can't be placed on the front wall to avoid notches caused by wall reflection. Placement remote from the wall moves the lowest lambda/4 distance into the omnidirectional frequency range. The resulting notch can't be compenated by EQ. All other speakers you listed leak even more sound to the rear.

Interesting presentation of the data. I don't think you give enough credence to the tradeoffs made between designs and, honestly, are too focused on the Palmer. But you have set your priorities, even if I disagree with them.

Here's the C8C, rear-radiation centered. I'd stick an absorber on the back.

 

[zonk]

Neumann is currently updating their KH310, KH420 with DSP functionality.

The Ascilab are in Europe only available in one online store. And before someone is buying anything there, I recommend to read their return policy carefully.

 

[AudioJester]

Did a quick dirty measurement of my C8C/BX8C combo, speakers basically plonked in corners, measurement at 3m. Still need to work out best positioning, very easy to move around on felt feet provided by Ascilabs - but have just been enjoying and not tweaking

C8C alone, this what I thought was optimal position in my room - 2m or measuring distance from memory

C8C and BX8C

 

[RexrothPigeon]

The Ascilab are in Europe only available in one online store. And before someone is buying anything there, I recommend to read their return policy carefully.

Ascilabs' Europe distributor is Audiophonics, which has to abide by EU regulations.

 

[illusonic]

@stoneeh made measurements of the hiss. His sample had 40dB SPL at 10cm: link. Around 3min20sec. That's as high as PA speakers. This makes the speaker impossible to accept--for me. Based on some comments here over the years, some people are amazingly tolerant or amazingly oblivious to hiss. My first experience with an active speaker with silent hiss was the Neumann KH80, with hiss around 15dB SPL at 10 cm. There I actually have to put my ear to the tweeter.

And his comment was inaudible at 1m. About the same everyone is saying. At some point it makes sense to also pay attention to subjective impressions. Especially when acoustic noise measurements close to audibility threshold are involved.

I found compression measurements by @Nuyes: link. Starts around 4min.

So above 86dB free field Orbits start to limit in lower bass, which we knew before. Factoring in 8-12dB room gain and 6dB for the second speaker that's a sensible choice. Most people will not even need a sub because 30Hz output is actually quite impressive at 2.5m distance in a 35m2 room. I never got the speakers into limitation with music playback, while I can enjoy those occasional 30Hz btw. more often 35Hz notes. The -6dB bass shelve I use to compensate room gain certainly helps, as it shifts the onset of limitation to 92dB free field level. I don't think people with normal hearing listen at such levels for longer periods. If they do their hearing status will change soon.

As you can see below, Kii 7 limits above 76dB and even in that case I consider it a good idea to provide sub 30Hz extension at lower listening levels. Now you could say the Palmer engineers and Bruno Putzeys have no clue what they are doing. I say they know exactly what they do and it makes a lot of sense.

Out of interest, I took the time to plot them all. The level of variation is a little better for Genelec than it is for the Palmer speakers, though I wouldn't call either manufacturer's spec frequency response all that representative.

That said, @stoneeh's low frequency measurements look off. Groundplane is accurate, and gated measurements are certainly accurate over 1kHz, I wouldn't contest that, but I think it must have been cold outside, cold enough to cause the woofer surround compliance to change. Nothing to do with break-in, unlike what he says in the video.

Temperature was also my first thought when looking at the 8351B's bass response. But it was a sunny day in spring which doesn't look too cold to me. The ASR measurement also shows tilted bass with a dip at 75Hz, so there is definitely something. I expect the dip to be caused by variation in the woofer's resonance frequency increasing the distance to the bass reflex resonance. There can be influences of temperature and also a break-in effect on surround compliance. But production tolerances can't be ruled out at this point.

The Genelec plot looks like a simulation below 400Hz. It also misses the steep drop below the bass reflex resonance. So Palmer measurements are more reliable as it seems. Any reason you showed the Palmer and Genelec plots with different vertical scaling? The Orbit plots would look much better with the Genelec scaling.

 

[traind]

Did a quick dirty measurement of my C8C/BX8C combo, speakers basically plonked in corners, measurement at 3m. Still need to work out best positioning, very easy to move around on felt feet provided by Ascilabs - but have just been enjoying and not tweaking

View attachment 537146
C8C alone, this what I thought was optimal position in my room - 2m or measuring distance from memory

View attachment 537147
C8C and BX8C

So the addition of the BX8C smoothed out the curve noticeably? Or does the different scale between the two charts have more to do with the curve being smoother? Basically, help me interpret the results!

 

[illusonic]

Interesting presentation of the data. I don't think you give enough credence to the tradeoffs made between designs and, honestly, are too focused on the Palmer. But you have set your priorities, even if I disagree with them.

My main priority is good sound. But certainly not at any cost. And I know there are many people who love good sound as much as I do but can't spend as much as I can. So when I see a product with outstanding value for money, I recommend it to others. What are your priorities?

I see the engineering excellence in all Ascilab, Neumann, D&D, Genelec and Kii Audio speakers. But actually even more so in the Orbits. It's one thing to deliver excellent results with big budget. But it's much harder to achieve the level of performance the Orbits deliver for the given sales price. And I also think the tradeoffs that the Palmer engineers chose between the performance level of various features of the Orbits and the production/engineering cost are just right.

For anyone willing to spend almost 6k€ for a pair of speakers, I would not hesitate to recommend the C8C based on absolutely excellent measured performance. I also rate the measured C8C performance above the 8C and the KH 420. So it's also much better value for money in my view.

For smaller budgets, the Orbits can be recommended at merely 1.6k€ a pair. And the audible distance to the bigger speakers will fortunately be much smaller than the price may suggest. At and below the Orbit's performance level, I see a lot of higher priced speakers including Ascilab, Neumann, Genelec and Kii Audio offers. On that background I don't see that the Orbits have enough support from knowledgeable people in this forum. That's why my focus is on the Orbits.

Here's the C8C, rear-radiation centered. I'd stick an absorber on the back.

Yes, the C8C might benefit from an absorber. That midrange leakage on the rear results from the vertical offset between the midwoofers and the woofers. Kii 3, 8C and the Orbits perform better in that regard. But I don't think it's a big deal.

 

[illusonic]

In other words, nothing reliable. In such testing you wouldn't even have the ability to control distortion as a variable.

Frequency response, THD and IMD vs level are known from respective measurements. How you would control distortion as a variable in speaker listening tests?

 

[Curvature]

What are your priorities?

Cardioid down to roughly 100Hz, controlled vertical and horizontal radiation, nice appearance, not too big (small living room), reasonable price (vs. competitors, not on an absolute basis), decent output at 40-50Hz, active but low self-noise, with XLR inputs. I think that's all.

I can't make measurements at my house at least for another month, but it's easy to demonstrate how audible 40dB SPL of self-noise is by setting it against other sounds, like speech. I have a certified SPL calibrator for microphones if there is doubt about accuracy.

 

[illusonic]

Cardioid down to roughly 100Hz, controlled vertical and horizontal radiation, nice appearance, not too big (small living room), reasonable price (vs. competitors, not on an absolute basis), decent output at 40-50Hz, active but low self-noise, with XLR inputs. I think that's all.

So the C8C would be almost perfect for you. Maybe with a coax for better vertical radiation.

I can't make measurements at my house at least for another month, but it's easy to demonstrate how audible 40dB SPL of self-noise is by setting it against other sounds, like speech. I have a certified SPL calibrator for microphones if there is doubt about accuracy.

40dB may be audible, the Orbit's noise in my living room is only audible if I approach them closely. And my hearing is still ok. While I kind of like the fact that my Purify amps exhibit inaudible noise even right at the tweeter of my passive speakers, I don't think this is required for larger listening distances. And the stereo amp costs almost as much as the pair of Orbits.

 

[tifune]

Yes, the C8C might benefit from an absorber. That midrange leakage on the rear results from the vertical offset between the midwoofers and the woofers. Kii 3, 8C and the Orbits perform better in that regard. But I don't think it's a big deal.

What type of absorber do you have in mind?

 

[Curvature]

What type of absorber do you have in mind?

A few inches of Basotect to absorb down to 400Hz.

 

[AudioJester]

So the addition of the BX8C smoothed out the curve noticeably? Or does the different scale between the two charts have more to do with the curve being smoother? Basically, help me interpret the results!

Its a bit of both. The curve is definitely smoother, but not a proper controlled measurement - different speaker positions, tweeter height is now different with the BX8C, different measurement distance from speakers and different output level. All things that should be unfavourable to BX8C addition!

It sounds quite different, much better. Just added a Gsonic convolution filter for added bass control, its better than my Acourate attempts. I have had over 10 speakers in this listening space over the years. The best way I can describe the Ascilabs combo is that it sounds like a different room - it no longer sounds like my listening space. I have heard some very highend/expensive speakers in huge demo spaces where the room disappears, thats the experience Iam having. Quite amazing!

I need to redo controlled measurements from same position with REW and switch BX8C on and off to show difference better.

@AsciLab - is there a simple way with the AES daisy chain and preset buttons to switch BX8C on/off? Currently source -> Right BX8C -> Right C8C -> Left BX8C -> Left C8C.
Also, any tips for measuring these speakers in room?

 

[tifune]

A few inches of Basotect to absorb down to 400Hz.

Anything you can recommend off the shelf? GIK, etc?

 

[Curvature]

Anything you can recommend off the shelf? GIK, etc?

Anything would do. Any kind of acoustic foam, denim or fibreglass filling, maximum thickness allowable by your space, directly behind the speaker. Basotect is not really off the shelf but it can be ordered from manufacturers at custom sizes, although it is fairly expensive. I mentioned it because it comes in a nice pure white.

 

[illusonic]

Don't know where you're located. In Germany Basotect is offered on amazon. Judging on panel thickness, GIK shows absorption coefficients for diffuse sound fields (compare diffuse vs. vertical sound incidence below). So it would probably be best to use their bass trap panels with 10cm thickness. I would rather get raw panels from amazon and wrap them in acoustically transparent fabric.

Left plot Basotect absorption coefficient in reverberation chamber (diffuse sound field), right plot absorption coefficient in impedance probe (vertical sound incidence) link. For first order reflections (speaker - front wall - listener) sound incidence is almost vertical. Therefore, I would use 100mm.

 

[829]

Interesting presentation of the data. I don't think you give enough credence to the tradeoffs made between designs and, honestly, are too focused on the Palmer. But you have set your priorities, even if I disagree with them.

Here's the C8C, rear-radiation centered. I'd stick an absorber on the back.

View attachment 537133

Don't know where you're located. In Germany Basotect is offered on amazon. Judging on panel thickness, GIK shows absorption coefficients for diffuse sound fields (compare diffuse vs. vertical sound incidence below). So it would probably be best to use their bass trap panels with 10cm thickness. I would rather get raw panels from amazon and wrap them in acoustically transparent fabric.

Left plot Basotect absorption coefficient in reverberation chamber (diffuse sound field), right plot absorption coefficient in impedance probe (vertical sound incidence) link. For first order reflections (speaker - front wall - listener) sound incidence is almost vertical. Therefore, I would use 100mm.
View attachment 537331View attachment 537333

Amazing explanations, thanks!

But please @illusonic, could you remove that tracking-part of your Amazon link?:

?dib=eyJ2IjoiMSJ9.gtAWG6YbDX3AcH4u5YJSNd2U6mGhX4OA4SOaxPIjXAYyMB3E1CpILq1dk5kvyjZdivX4Yw7nPBZ1NfY4Cpsk7HXHk6VRDAB6W3saEd4LMPDIGrMZ3zBNuzsbLdJ8WUB-1i8kTzuuJyNciYpDQ4UwmmLQf8I4xRCN6sMRWcR91RHtHqidFEoxiw5uSUXxaaWIE_aKIMP8pZsS2jCo7GZPQWkN8btFtR07Lb37g007MuQ.tE13GRwNFGm__NSmiCqVWqiVtckDgAlDdfIopUPiaA0&dib_tag=se&keywords=basotect&qid=1780775595&sr=8-4&th=1

Clean link looks just like that: https://www.amazon.de/soundSTOMP®-S...challdämmung-Akustikoptimierung/dp/B0DPXSY6L6

 

[AsciLab]

Its a bit of both. The curve is definitely smoother, but not a proper controlled measurement - different speaker positions, tweeter height is now different with the BX8C, different measurement distance from speakers and different output level. All things that should be unfavourable to BX8C addition!

It sounds quite different, much better. Just added a Gsonic convolution filter for added bass control, its better than my Acourate attempts. I have had over 10 speakers in this listening space over the years. The best way I can describe the Ascilabs combo is that it sounds like a different room - it no longer sounds like my listening space. I have heard some very highend/expensive speakers in huge demo spaces where the room disappears, thats the experience Iam having. Quite amazing!

I need to redo controlled measurements from same position with REW and switch BX8C on and off to show difference better.

@AsciLab - is there a simple way with the AES daisy chain and preset buttons to switch BX8C on/off? Currently source -> Right BX8C -> Right C8C -> Left BX8C -> Left C8C.
Also, any tips for measuring these speakers in room?

Set the preset P1 or P2 of C8C
Then you have to reconnect the cable.
Sorry, There is no other way.
I connect(extend, maybe?)the “through” cables when I off the BX8C. I mean I just connect the C8C only.

As I wrote in manual, you’d better keep the distance from the front wall to the baffle less than 1.6-2m. I recommend less than 1.6m with P2(Standard Cardioid Mode). And also recommend to use REW than the other measurement software.

REW can show excess phase(group delay) that means it can’t be recovered by EQ, cancelled out by strong room reflection. It is the worst thing by room reflection, even worse than strong resonance(resonance peak can be cut by precise parametric EQ).

When you set the speaker position, measure each presets in your listening position, it will be fun to compare to C8C only. If you don’t have any strong dip or phase error in P1(Max SPL) use it, but if you get better bass response by the other presets, use them. That’s all.