D'Appolito isobarico

[Stee]

Modern loudspeaker configuration is an internal Push-Pull

natural sound comes from complementary copules
two drivers are mounting inside an isobaric volume
and connected in reversal polarity

the other bottom volume (about 2X Vas) is closed

in my case four Morel MW166 plus tweeter Vifa XT25 for each channel

Happy New Year

[bjorno]

Hi,

What type of modern XO are you using? What are the XO frequencies, the m-t-m c-c distance and are measurements available?

See the picture where I tested some 12 dB filters:

b

Picture 1(1)

[planet10]

I built a couple pairs of MTM isobariks back in the early 80s (KEF T27+B200x4 and T27+B110x4). They both suffered from the predicted suckout of an isobarik operating into the midrange. The upside was a very distinct removal of box signature from the sound.

dave

[Stee]

I built A LOT of couple pairs of MTM isobariks back in the 90s
now i have found the secret:

it's very important have distance between external/internal wfrs
inside isobaric room
that create a tuning in different tone ( do - mi - la )

distance m - t - m is 150mm (axis to axis)
so totally 300mm m - m

at the moment just twt is filtered