Coax project using Audison Voce II AVX 6.5 II speaker

[ppataki]

After some failed attempts (this and this) I am still in search for a good pair of 6.5" coax drivers
(one can say I am persistent)

This is the next one on my plate:

Audison AVX 6.5 II VOCEI II hi-res concentric coaxial

The Audison Voce AVX 6.5 II concentric coaxial delivers Hi-Res sounds with a pulp-paper cone and advanced crossover for pure, detailed audio.

audison.com

Not so cheap and the measurements also don't look super nice but the TS parameters look great (I will do the simulation and post it later today) and hopefully there will be no issue with air leakage....

It seems that it was optimized rather for off-axis listening?

Any comments are welcome before I pull the trigger

 

[Trdat]

What are you designing? Just curious....

My 2 cents worth, coax with cardoid bass but a large version.

Was the Sica coax not good enough or you just want a different driver?

 

[ppataki]

What are you designing? Just curious....

Nothing special, just putting these different drivers in my sealed sphere cabinets (the white space balls ) and 'see what happens'

My 2 cents worth, coax with cardoid bass but a large version.

I will keep it at 6.5" - that matches the size of the spheres

Was the Sica coax not good enough or you just want a different driver?

The small Sica was excellent, very strongly recommended, as I also stated in my project thread; actually one of my friends is enjoying them now
They are too small for my cabinets, so the 6.5" version is still on my target list but in the meantime I am venturing into other exotic areas, like automotive speakers just to gain experience (and for fun too)

 

[ppataki]

As expected, the simulation looks pretty good:

Xmax limited maximum input power will be 85W at 80Hz (where it will be crossed to the sub)

Which will give approx 103.5dB SPL at 1 meter (=109.5dB for stereo)

I plan to order them in the coming days

 

[voodooless]

It seems that it was optimized rather for off-axis listening?

That’s the golden rule for all coaxials, isn’t it. They are almost always more linear slightly off-axis.

As for this particular thing, I don’t know.. it doesn’t look particularly special, it’s car audio… who knows? There are some great car audio products around, and a lot of terrible ones.

 

[ppataki]

There are some great car audio products around, and a lot of terrible ones.

We will soon find it out.....

 

[voodooless]

How about these:

https://www.beyma.com/speakers/Fichas_Tecnicas/beyma-speakers-data-sheet-coaxial-6CX200NdN.pdf

 

[ppataki]

How about these:

https://www.beyma.com/speakers/Fichas_Tecnicas/beyma-speakers-data-sheet-coaxial-6CX200NdN.pdf

These would be an excellent choice, I agree, however I would only put round shaped drivers in my sphere cabinets, otherwise they would look weird (this is just a personal taste thing)

 

[voodooless]

These would be an excellent choice, I agree, however I would only put round shaped drivers in my sphere cabinets, otherwise they would look weird (this is just a personal taste thing)

Put a round cover on them, or just a ring to cover the basket.

 

[ppataki]

I have just placed the order for the AVX 6.5 II, let's see when they arrive
I will share the pictures as soon as I get them
Stay tuned!

 

[tjf]

time to try this:

SEAS Launches Toy DIY Kit With Metamodal TPCD Coaxial Driver

SEAS launched a new DIY kit to highlight the qualities of its state-of-the-art Metamodal TPCD coaxial drivers, allowing everyone to build a working speaker for evaluation and enjoyment. An evolution of the popular SEAS Joy kit that the speaker manufacturer already offered with a single coaxial...

audioxpress.com

 

[ppataki]

time to try this:

SEAS Launches Toy DIY Kit With Metamodal TPCD Coaxial Driver

SEAS launched a new DIY kit to highlight the qualities of its state-of-the-art Metamodal TPCD coaxial drivers, allowing everyone to build a working speaker for evaluation and enjoyment. An evolution of the popular SEAS Joy kit that the speaker manufacturer already offered with a single coaxial...

audioxpress.com

Interesting, although one would need a ton of DSP to get from this response:

Source: https://doc.soundimports.nl/pdf/brands/Seas/C16NX001-X/C16NX001-X-Datasheet.pdf

To this response:

They also admit that in the article itself:

TBH I am not sure I would pay 1300 EUR for these
(https://www.soundimports.eu/en/seas-c16nx001x.html)

One could similarly apply this amount of DSP to much less expensive drivers to get a great on-axis response (I have been doing that with a lot of my one-way full range projects)

 

[PB63]

Above graph is not on-axis, it's 10 degree's off!

I have the Sica 6 Cx 2PL, I got some eq around 2kHz due to loading and some at 7kHz. With this low q driver, no wonder the bass extension is bad, the Beyma would be similar. I got a 50cm baffle close to the wall + some shelving to get them down to 120Hz. For my level of listening this is fine. I don't bother with distortion measures...

 

[ppataki]

Above graph is not on-axis, it's 10 degree's off!

I have the Sica 6 Cx 2PL, I got some eq around 2kHz due to loading and some at 7kHz. With this low q driver, no wonder the bass extension is bad, the Beyma would be similar. I got a 50cm baffle close to the wall + some shelving to get them down to 120Hz. For my level of listening this is fine. I don't bother with distortion measures...

I was also considering the Sica 6 Cx 2 PL but I ditched it because of the same reasons you mentioned above (very weak in the bass region)

This is the simulation of the Sica 6 Cx 2 PL (orange) vs the Audison Voce II AVX 6.5 II (red) in my sealed sphere cabinets:

The Audison is almost 8.5dB louder at 80Hz

 

[voodooless]

Well, yes, obviously, given the low Qts. It should do well in reflex, though possibly in a larger than wanted enclosure.

 

[ppataki]

Just a very quick update: the speakers are on their way, I shall get them early next week

 

[nc535]

i think your prioritization of the bass response of the coax is misplaced. That is easily fixed with a woofer which you will need anyway, given that even the best 6" woofer won't be enough on its own. A smooth top end, on the other hand, is priceless! I understand you are targetting a spherical cab. Couldn't you put a 2nd woofer facing the back (or down) for 100 hz and down?

 

[ppataki]

i think your prioritization of the bass response of the coax is misplaced. That is easily fixed with a woofer which you will need anyway, given that even the best 6" woofer won't be enough on its own. A smooth top end, on the other hand, is priceless! I understand you are targetting a spherical cab. Couldn't you put a 2nd woofer facing the back (or down) for 100 hz and down?

As I mentioned in post #4 these will be crossed at 80Hz
To this sub and to this sub

I have been doing this with many previous 6.5" speakers (including my current speakers) and if they are designed properly (no air leakage, adequate xmax, etc.) then it works perfectly

 

[ppataki]

The speakers have finally arrived!

You can see the external passive crossovers on the left hand side
They have also provided some gaskets, screws, stickers..... really comprehensive package!

The big question is: will they fart?

Tonight I will put just one of them in my sphere cabinet and see if it farts (air leakage) or not..... fingers crossed
Stay tuned!

 

[ppataki]

Let's see the measurements!

As usual, all measurements were taken in the MLP (approx. 250cm from the speakers)

Woofer response:

Tweeter response:

Not too bad!

Let's see the distortion graphs.....

Yes, unfortunately these drivers do fart too....
However, not nearly as much as the ESBs that I measured last time; it is more comparable to the Sica 5.5" coax drivers actually
(red: Audison, cyan: Sica, purple: ESB)

So I think it is safe to say that generally speaking one is better off using coax drivers in reflex cabinets, where air can flow from the cabinet through the reflex tube instead of the speaker driver itself....

Let's see the response using linear phase LR crossover at 4kHz, 24dB/octave (Fabfilter Pro-Q 4)

(I forgot the 80Hz high-pass filter on, hence the rolloff in the low end)

I would say it looks good, actually very similar to that of the ESB drivers and way better than the Sica drivers (I needed a dozen of pre-EQ filters to make it look like this)

Step response clearly shows a perfect time alignment of the drivers:

All this without any digital time delay correction! I have measured a difference of 0.005ms between the tweeter and the woofer - this is outstanding! I have never seen any coax driver like this, with practically zero time difference out of the box

I have integrated my subs and applied Dirac Live correction (that made the response even smoother) and I have to say it sounds pretty damn good!!

I will share my subjective experiences in a subsequent post
I plan to keep them for further listening and they might even replace my Markaudio MAOPs..... will see