I would like to introduce my latest design, the Apica.
It has an 8” woofer with honeycomb cone and a planar tweeter with waveguide.
It has a 20 liter closed cabinet with high pass and delivers bass down to about 37Hz (f3).
Here are the measurements of the driver in the housing without crossover:
And the measurements with crossover:
Please note that this measurement is only valid from 200Hz upwards and does not show the real behavior in the bass.
Detailed information is available on our website, unfortunately only in German:
https://www.der-akustische-untergrund.de/speakers/advanced-level-projects/apica/
The project was created in cooperation with hs-sound.de, but I will not be involved in the sale.
https://www.hs-sound.de/Apica
It has an 8” woofer with honeycomb cone and a planar tweeter with waveguide.
It has a 20 liter closed cabinet with high pass and delivers bass down to about 37Hz (f3).
Here are the measurements of the driver in the housing without crossover:
And the measurements with crossover:
Please note that this measurement is only valid from 200Hz upwards and does not show the real behavior in the bass.
Detailed information is available on our website, unfortunately only in German:
https://www.der-akustische-untergrund.de/speakers/advanced-level-projects/apica/
The project was created in cooperation with hs-sound.de, but I will not be involved in the sale.
https://www.hs-sound.de/Apica
Hello ! Schönes speakers !
Please can you post the response curve or communicate the frequency range of your acoustic chambers in dB.
Good night !
Please can you post the response curve or communicate the frequency range of your acoustic chambers in dB.
Good night !
Interesting design. Would HS ship to the UK do you know? I can't find a field for England in their shipping section.
Thank you!
The Apica behaves like this below 200Hz (blue curve):
It therefore plays from 40Hz to 20kHz with a fluctuation range of less than 2dB.
Just under 40Hz cut-off frequency (f3) doesn't sound like much bass on paper, but thanks to the GHP principle, the frequency response in the low frequencies doesn't drop as quickly as with bass reflex and therefore there is no lack of low bass.
This speaker also plays very low bass-heavy music excellently. “Doin' it right” by Daft Punk, for example, goes very low and the Apica manages this without any limitations.
Thanks.!
I think I realise the similarities with these drivers and others so I may try a homebrew version!
What is the 'GHP' principle please.
I think I realise the similarities with these drivers and others so I may try a homebrew version!
What is the 'GHP' principle please.
Not sure if there is an official English term, it’s German for
as in, a closed box with high pass:
https://aes2.org/publications/elibrary-page/?id=15513
To what angles has off axis been measured? I may have overlooked that in the text, but could not find a legend.
Hi!
I asked Hendrik from hs-sound. He actually only ships within Germany, but on request by email he can also offer shipping to the UK.
The tweeter is made by HiVi/Swan, but the woofer is made for hs-sound. You probably won't get it anywhere else. You can't use a different one without adjusting the crossover.
With GHP, the woofer is placed in an actually too small, closed cabinet with a Q factor of 0.9-1.2.
If a large capacitor is connected in front of it, the boost in the upper bass disappears and you get more depth.
This is what it looks like:
Black is the behavior in the small closed cabinet, red with capacitor.
The advantage is that you can achieve quite a lot of depth with very small volumes.
This simulation is only an example and does not show the Apica.
@Lojzek:
It's not about selling, I just wanted to present the development.
@Boden:
The measurements in the diagram above range from 0-60 degrees.