follow up on ZA 14 vs Fountek

[r-carpenter]

This is a follow up to the ZA vs Fountek mid woofers.

http://techtalk.parts-express.com/showthread.php?t=215217

[r-carpenter]

Re: follow up on ZA 14 vs Fountek

some shots while building

[dbe]

Re: follow up on ZA 14 vs Fountek

This is a follow up to the ZA vs Fountek mid woofers.
http://techtalk.parts-express.com/sh...d.php?t=215217

Nicely done, very nice. Don't see mitered joints around here very much what with most of us being **** joint kinds of guys.

Dave

[r-carpenter]

Re: follow up on ZA 14 vs Fountek

en voala! layer of viscous elastomer is being applied inside before foam.
tweeters are off center for less diffraction.

[dbe]

Re: follow up on ZA 14 vs Fountek

Nicely done, very nice. Don't see mitered joints around here very much what with most of us being **** joint kinds of guys.

Dave

Can't even say b[]tt joint here... good grief. No wonder I got a warning for saying the proper name of a contraceptive device here a while back. PC run amok, amok, amok, amok.

Dave

[r-carpenter]

Re: follow up on ZA 14 vs Fountek

Thanks.

Did anyone experimented with asymmetrical port placement? I mean in relation to a vertical center of the panel. I wander what kind of the effect it has on the midrange leakage.

The speakers are 4.5L after the drivers and brace.

[evilskillit]

Re: follow up on ZA 14 vs Fountek

Nicely done, very nice. Don't see mitered joints around here very much what with most of us being **** joint kinds of guys.

Dave

I am all about the bütt joints. Being that my table saw sucks and all.

[Pete Schumacher]

Re: follow up on ZA 14 vs Fountek

Thanks.

Did anyone experimented with asymmetrical port placement? I mean in relation to a vertical center of the panel. I wander what kind of the effect it has on the midrange leakage.

The speakers are 4.5L after the drivers and brace.

Excellent question and astute conclusion. It has a MAJOR impact on midrange output in the passband of the woofer. Not only does the port resonate at a particular frequency, causing a ripple in overall response, it can allow a broad range of output that can mess with the sound.

If possible, get it away from a position directly behind the woofer. An unobstructed pathway will allow much more information out than one where absorptive material is in the path. Loose fiberfill in the enclosure helps reduce the effects as long as airflow from the port is maintained.

[r-carpenter]

Re: follow up on ZA 14 vs Fountek

Thanks Peter. I was going to place the port in the upper section of the cabinet, somewhat behind the tweeter. But now my curiosity is running wild. I'll make 2 or 3 dummy panels and move port from the very corner to a vertical center line and measure the output.
Then I build these speakers

http://techtalk.parts-express.com/album.php?albumid=247&pictureid=2038

port (2x9) was placed directly behind the RS180. It had an interesting effect and the speaker sounded somewhat "dipolish"
I also build this one a couple of years ago with down firing 2x9 flared port.

http://techtalk.parts-express.com/album.php?albumid=247&pictureid=2023

and that one had the best imaging that I've heard ever from anything else in my life.
So, I think port placement and how it relates to the sound especially in a 2 way design are worth playing with.

[r-carpenter]

Re: follow up on ZA 14 vs Fountek

back panels are ready for binding posts.

[r-carpenter]

Re: follow up on ZA 14 vs Fountek

ZA14/ProAcVifa combo= Zavic?Prozac?Fazac?

[r-carpenter]

Re: follow up on ZA 14 vs Fountek

made 3 dummy panels to play with port placement but that will be done next week.

[r-carpenter]

Re: follow up on ZA 14 vs Fountek

4 back panels are made
one with port pretty much behind the driver, vertical center line
second has the port in the upper section also vertically centered
one with the port moved in the corner
and one with the port close to the side and 2/3 up from the base

[r-carpenter]

Re: follow up on ZA 14 vs Fountek

Each panel is just clamped in for measurements. Microphone is about 1/4" in the port.
Levels remain constant throughout and only the backs are changed.
Speaker does not have any padding or stuffing, just a thin layer of elastomer.
First take is with the port located in lower section, vertical center.
gating, 500msc distance set at 0.

[r-carpenter]

Re: follow up on ZA 14 vs Fountek

from the left

port in the center upper section
port in the upper section close to the sidewall in the midle
port in the upper left corner