From full range to two ways: crossing Pluvia 11 eleven

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Hello I' m thinking to help the mid high of my Pluvia 11 which I'm finding a little dark. I 'm thinking to two solutions which I have not simulated yet. First idea is to cross Pluvia 11 with Pluvia 7.2 HD, put in a small volume closed box using a 6db crossover. Is that good? The second option is to parallel Pluvia 11 with Fountek Neo Cd 3.0 ribbon tweeter using R Lpad plus serie capacitor. I'm curious and little attracted about ribbon tweeters (but need them in a circular frame). Never tested.
Any suggestion please?
 
Speaking for myself, I've had my fill of ribbon tweeters. With certain exceptions I regard them as a complete and total pain in the jacksie. Chronic distortion on the low end requiring 3rd order or > filtering if you don't want that warbling away, which with a 2-way then usually means a merry time getting the polar responses balanced properly if you don't want the tonal balance to go to bits. Speaking as someone who designs both single driver & multiway speakers, I've been there, done that, pulled my hair out, was never satisfied, walked away and haven't looked back.

On the other hand, using a smaller wideband driver for the HF is -interesting. This is the approach MA-Sota took for their multiway systems. Since I'm allergic to 1st order crossovers (especially at low frequencies) the multiway MA-Sota speakers used variations on my preferred offset B2. They worked rather nicely within their design remit, albeit the subjective behaviour is a little different from what you might expect on a graph. As Chris says, I'd be more inclined to use the A5.3 than P7.2 though.
 
Ok! Thanks I will give up for the ribbon tweeter.
I was selecting Pluvia 7.2 because it is the only vintage gold speaker and goes till 30kHz.

Check my existing
Homemade Audio| Fullrange single driver speaker | Pluvia 11 Eleven

I can change to A5.3 but the gold is different. Maybe I can combine Gold Pluvia 11 with Grey A5.3 or the two different golds can esthetically match?

How big (liters) should be the volume of the second box to put on top of my existing speakers by using A5.3? It would be a closed box correct?
 
frugal-phile™
Joined 2001
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TO my mind a 2-way with Pluvia adds a bass driver. The P7HD should have better mid/top and while it can’t move as much air, can be tuned lower in a BR than P11.

If you want to use it as a bass driver, Pensil or FHXL (big box to get bass out of them), and A5.2 as Chris suggests or one of the 2 A6.2.

dave
 
frugal-phile™
Joined 2001
Paid Member
...but the gold is different.

I’ve not seen the “gold” P11, but the Alpairs (since Gen 2) are copper not gold.

How big (liters) should be the volume of the second box to put on top of my existing speakers by using A5.3? It would be a closed box correct?

It could be sealed (at least 2litre, 5 would be better, i’d use the space on top of your speaker to do an aperiodic midTL (what are the wxd dimensions of your speaker?

Your BR is tall enuff to actually be an ML-TL, but with the vent entrance you are fighting that. What is the net volume & tuning?

dave
 
Our practice with the half dozen or so two-ways of this type has been in the 200-330Hz range, biamped with 1st order line level passive crossovers - both lo and hi pass. I'm not about to suggest that's the only approach, but it's certainly very inexpensive if you have extra amps kicking around, which was certainly never an issue for us.
 
frugal-phile™
Joined 2001
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An XO between P11 & A5.2 could be anywhere between say 250 Hz to 2.5KHz. 300 Hz is the approximate mid-point of driver energy, so it is common. You want to pay attention to the c-c distance of the drivers, if you can keep the XO at or below the 1/4 wavelength of that distance the drivers will essentially be coincident. And pay attention to baffle step, the XO point ideally 0.707-1 times the BS(-F3).

Withing reason, higher XO will allow you to play louder.

Bi-amping makes things way easier.

dave
 
Why is 5w 'definitely too low'? :scratch1:

7P Gen1 = light blue uncoated paper cone.

By symplifying the view ( nominal=rms; resistive loads)
If XO will be around 350Hz you have P11 covering 4 octaves handling 45W at 8 ohm. The ampli can output 19VRMS. A5.3 would cover 5.5 octaves handling 5W at 4 ohm. The ampli would be limited to a 4.5VRMS signal before generating issues to the driver.

7P Gen1 is 20W at 8 ohm that means can handle a 12.6VRMS signal. (Maybe more as its sensitivity is higher than A5.3 and could even require a serie resistor in the XO.)

My amplifier is a multi op-amp paralleled supplied by +/-15V and can output around 9.5 VRMS without distortion. For a 1KHz note I see too much for A5.3 but below 7P Gen1 limit. Or am I missing anything?

Is 7P Gen 1 a good musical choice? BTW i still need to think how combine light blue...But music first...
 
Enhanced full-range multibox system (part 1)

I am and remain a big fan of the full-range single-driver systems: the naturalness and acoustic image they provide is superior to any multidirectional system with crossovers. The music played by a fullrange appears very natural, easy to listen to, with effortless details and realistic timbre along with a solid image of the soundstage.

Pluvia11 is a great speaker and offers excellent powerfull bass. I mounted it into a bass reflex box with a resonance frequency of only 38/39 Hz.
But it has limitations: it is very sensitive to the quantity and positioning of the damping material inside the cabinet, it is very directional, it sounds a bit dark and has some brightness peaks here and there. In short, it should be "slightly" helped and corrected in some way at the mid-high frequencies.

At first, I was just thinking of putting a rear-firing ambience tweeter simply connected in parallel through a serial RC network, which helps a lot to correct the medium-high frequencies, thus allowing PLUVIA11 to continue covering the entire sound spectrum without any LP filter in series in the latter. Unfortunately, this has led to an imbalance in the total electrical impedance and, even if the rear tweeter greatly expands the soundstage on one side, it compromises the sharpness and clarity on the other, resulting in a slightly tired and artificial long-term effect. The Haas effect, which is basically the main cause of ambient tweeters' good job, makes the brain work too much: artifacts are being created into the acoustic scene that originally did not exist in the digital recording.

The second alternative (which I am going through) is to go on an almost traditional two-ways speaker, trying to limit the phase distortions as much as possible in order to don't jeopardize the advantages of Pluvia11, that means focus and naturalness of the acoustic scene.

Hence, my single driver loudspeaker is going to become an "enhanced full-range multibox system" based on a minimal first-order filter with a new additional tweeter-box tilted back and angled slightly toward the listener in order to optimize its time-domain relationship with the Pluvia11 speaker below.

(end part1)
 

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