Ciare design idea

[Helmuth]

I had begin this year a design idea with ciare drivers I want to share with you. It is designed to have low group delay and a few db extra low to compensate the 4phi radiation.

And using all time classic softdome drivers

The design


The drivers



Filter.

[Helmuth]

Design goals:

High quality stand-loudspeaker compact size.
High price performance ratio.
Dome tweeter midrange for reproducing the most important frequency range.
Two sub-woofers to guaranty sub-bas although radiating in full space 4π.

Explanation design choices:
Bass:
For good music reproduction good bas performance is of the highest importance. The bass fundament carries the stage of the reproduction.
The problem with most speakers is to lack of good sub-bas because it needs big surface to make bas down to 30Hz at 90dB/1Wmtr. And it radiates into full space so the efficiency drops due this effect on bigger distance. Because mid and high radiate in half space 2π with higher efficiency. Small BR-enclosures can reproduce sub-bas although they suffer colouring by high extrusion and high group-delay figures.
The HS250 have very good linear midrange, high extrusion motor xmax=8mm witch ensures low total harmonic distortion and linear extrusion and sub-bas up to 200W. I will design a BR enclosure but the driver behaves almost like in a closed box and has its low group-delay in the good audible area down to 45Hz. Then it will slightly rise.
Group-delay is a negative behaviour of a BR. There done listening tests and the outcome is to keep the ratio: group-delay X frequency < 400. A goal this speaker keeps control of.
The lowest HS250 driver will be cut off at 300Hz so it will be a 3.5 BBMT design. And it has a quality aluminium frame to ensure low thd.

Midrange:
What Ciare haven’t lost is making nice soft-dome midrange drivers like the MH500.
The midrange is what we from nature are the most sensitive to. What would it be nice to have one in this speaker design. It will fit perfect with the flat response of the HS250.

High range dome:
It has shown that making a good dome tweeter isn’t that difficult very cheep one can perform at the highest standard. Only the of axes shows witch ones are the best. Like morel CAT408 sold in matched pairs. Would perfect fit in this design.

To keep the price as low as possible I will be using the HT 250, the grill also helps increase the of axes response. And the mall diameter will help it place the right way on the baffle and on the good distance to the MH500.

[crazyhub]

Looks promising!
PA drivers are generally cheaper than hifi ones and quite good IMHO.
I'm presently begining to design a floorstanded 3-way with a side-firing 15"Ciare, an Eighteensound 8" + Scan-Speak tweeter. I guess I will enjoy playing around these drivers, LOL

[Helmuth]

Originally Posted by crazyhub

Looks promising!
PA drivers are generally cheaper than hifi ones and quite good IMHO.
I'm presently begining to design a floorstanded 3-way with a side-firing 15"Ciare, an Eighteensound 8" + Scan-Speak tweeter. I guess I will enjoy playing around these drivers, LOL

The HS250 are sold for 75 euro very flat midrange response aluminum chassis nice x-max for subbas.

Subwoofer Ciare Hs250 25cm 300w 8+8ohm


I will work out a active version with SURE class D TK2050 amp 4X100W 4 Ohm fits perfect in this configuration, because it very good and even cheaper then a quality passive cross over and we have a amp for each driver. This will be very loud and controlled.

[Helmuth]

Simulation of the woofers with filter at 300 and 650 hz.

And the response of the BR-port place near floor and on the back so in normal placement, near a back wall we can at 6dB to the port response. So we can have 20Hz -4dB in this situation. The port response shout be added to the front radiation to see the whole bandwidth.

The design has a lay out that uses the room gain in its advantage.

[crazyhub]

I think the 8mm x-max should probably be read as +/- 4mm linear travel. So a sub-bass, but only in a PA perspective. Don't expect earthquake vibrations but you're right about group delay with a "damped" Bass Reflex.

[Helmuth]

A goal was a low group-delay this bass-reflex has best of both worlds.

Almost same low group-delay as a closed-box and sub-low as a bas-reflex. To get direct undelayed bass.

And the big port keeps the air velocity low below 19m/sec at max power.

[Helmuth]

Originally Posted by crazyhub

I think the 8mm x-max should probably be read as +/- 4mm linear travel. So a sub-bass, but only in a PA perspective. Don't expect earthquake vibrations but you're right about group delay with a "damped" Bass Reflex.

I theory 112dB at 200W. That will shake you're apartment and that of your neighbor.

[crazyhub]

Originally Posted by Helmuth

Almost same low group-delay as a closed-box and sub-low as a bas-reflex.

Can you post the overlayed fr magnitude sim of both closed and vented?

[crazyhub]

Originally Posted by Helmuth

I theory 112dB at 200W.

At what a fr and power is the x-max exceeded?