Belle bass reflex mod

[sootshe]

I'm going to change from La Scala cabs to Belle bass bins & want to maintain the bass reflex mod to extend the bottom end. Does anyone see any potential issues with this? I figure it should be the same result with the Belle bins, but just checking.

Thanks, []

John

[sootshe]

Any opinions?

[garyeanderson]

Any opinions?

It might make for an ugly Belle. None the less I have
thought about it. I made the mod on a pair of Peavey FH1 bass bins and may move
one of the add-on chambers to the center channel Belle upstairs. The external
dimensions for the add on chamber were dictated by the hatch cover for the FH-1
and its 20 5/8 by 28 1/2 so it is a bit deep for the Belle but another bit of
Plywood on the top of the chamber would seal up the gap created by the Belles
18 1/2 depth. The height is 10 inches so the volume is close to that of the
lascala reflex chamber. The FH-1 currently have the round magnet K33 and
sound pretty good, not sure why but the ported lascala clones seem to sound
better but that’s not a side by side comparison, the FW-1 are in the back of
the garage with a pair of Cornwalls so its kind of an unfair to say that.

[garyeanderson]

Rigging in process, need to see how it works as its just a bit of work and no money spent.

[garyeanderson]

Rigged! and the glue is almost dry...

[sootshe]

Rigged! and the glue is almost dry...

Fantastic......please let me know your thoughts.

I've often tried listening to the LS without the BR extension, but it only lasts for about 5 minutes.....just isn't the same.

[garyeanderson]

Glues been dry for some time and has been playing since noon. One thing for sure is it lifts up the
tweeter and mid. With the tscm clones, the system is not bass shy, I am
going to put the tscm bins on a separate type A network and put the tscm clone
bass bins on the B channel of the receiver so I can cut them out them and still
drive the highs on the A channel. I doubt that the difference between a ported
Belle and ported lascala clone is noticeable by me, the clone has corner
reflectors, a full splitter, and rolls off on its own so its not really
anything that means anything other than in the context of this room. That said,
I will leave it for the winter.

[whatever55]

Could this same mod work for the Jubs ??

[PrestonTom]

Could this same mod work for the Jubs ??

The short answer is: No.

If you feel the need to extend the bass on a jub style cabinet, there is a very interesting project on re-creating the protype of the Jubilee bass bin with a drone.

Be warned it is not a straight forward project and the extension of the low end may be modest. If there is a serious problem about low end extension on a jub, then a sub-woofer would be a good solution.

Personally, I find the jubilee to be more than adequate.

[RRFL]

Could this same mod work for the Jubs ??

The short answer is: No.

If you feel the need to extend the bass on a jub style cabinet, there is a very interesting project on re-creating the protype of the Jubilee bass bin with a drone.

Be warned it is not a straight forward project and the extension of the low end may be modest. If there is a serious problem about low end extension on a jub, then a sub-woofer would be a good solution.

Personally, I find the jubilee to be more than adequate.

For myself the LaScala Bass mod is interesting, tempting, but I would stop at just the increase in the Doghouse volume and not introduce the ports.

For myself I have never heard a bass reflex that has sufficient transient performance to justify preference over the tight immediate response of the PWK design Horn Loading. I prefer a sealed enclosure like the Heresy over Bass Reflex. Bass reflex takes a while to get going and then a while to stop, so for me it's always late and that's compared to standard non time aligned LaScala.

To this end for myself I'm going to build a pair of 18"x18"x72" Tuba HT LP with the Dayton Audio RSS315HF-4 12" Reference HF Subwoofer 4 Ohm. Initially they will be stood mouth down 18" above the floor in the corners behind the LaScala.

For my Jubilee to deal with the LFE of movies when I'm in movie mode as opposed to stereo mode, I'm building a Tuba HT LP 36"x18"x72" to be laid on it's 18" edge against the rear wall with the mouth 18" away from the corner of the room.

I would never mess with my Jubilee, consider who the Jubilee designers are and seriously for me they have the experience, very latest knowledge, testing equipment and in comparison, I know nothing.

The Tuba is the same type of horn loading principal as the Klipschorn, LaScala, Belle and Jubilee and from my point of view has the best match potential to maintain the transient response and low distortion I have craved ever since I first heard the Klipschorn in the HiFi shop I was working in as a sales person back in 1975.

I frequently use systems with the Klipsch KPT-684 and KPT-682 and for myself I prefer my stock standard LaScala "with my 1981 class A Yamaha power amp and set in the corners" for their tight transient response and low distortion over the low bass extension of the Excellent KPT's mentioned.

So cutting through all my reasoning and waffle. If you want more lows under your Jubilee I say build a horn with a matching design specifically for that frequency band and don't mess with the "excellence" of the designers.

[garyeanderson]

The reflex port was removed. It may be something I would
have kept but the bass is not missing and the Belle reflex wasn't adding
anything due to the support of the Klipschorns and the fact that I play the
belle at a just audible level as a center. As such there is not much bass to be
heard/felt. I did some woofer robbing from another pair of Khorns I have and
installed them in the other clones I built last February. Most of the
time the cornwall clones are off, one reason is they are sharing the same
Pioneer A9 amp as the lascala clones, Playing both, my $90 Pioneer may not last
if I did. The other is it muddies the sound being offsetfrom the HF. Any or all bass bins will play with the Khorn HF. This is all lowbux as there is no money to get much else.