Re: [regsaudioforum] Re: Stirling Broadcast LS3/6 First Impressions
On Mar 9, 2013, at 7:49 PM, Charles Daniell <cfd@...> wrote:
Between REG, TM, and Yip, (who have all heard many great speakers,) we seem to have a speaker that is quite special! I do not ever recall such universal praise to be found here. Looks like I need to get a pair…
Just the SB LS3/6s and a subwoofer (or a pair of them), (mine is REL Stadium II, not in production anymore), and you will be audio heaven.
- Hi Laurie
I think the Q-factor of the reflex port is calculable or at least known by experience and becomes part of the equation. Like the electrical Q of chassis and the lowpass filter coil affects the optimum cabinet size, the shape of the reflex port requires adapting the length.
Placing straws into the port reduces crosssection and adds damping. It is most likely that upper midrange content from the rear of the cone cannot pass the port with the straws implemented as it acts more as a low pass filter then.
One way to reduce port noise is adding a foam ring around the inner end of the port. Like known from a flute, both ends of the port matter.
We dont know what the designer intended when dimensioning the port and selecting its shape.
> From what i remember of my friend's Celefs the straws were dipped in black paint which would be sticky until dried and this may be how they were fixed inside the port. Matt black I think prbably adds just that bit more resistance to the air flow - maybe an even rougher texture cement type paint even more so - being flippant now.
> I did read some years ago on another forum that the implementation of this type of straw/reflex design wasn't straight forward. So just stuffing straws in the port of an existing reflex design, might make things worse. The diameter and or length of the port might need to change for instance. I don't know who was the designer at Celef / Proac but it would be interesting to hear more from him / her about the ins and outs of this type of speaker.
> A few years ago on the Spendor forum there was talk of damping the port of BC1s using some sort of acoustic resistance, with some success. I think there was at least one change to the port design of the BC1 over the years it was in production and I've a feeling that final versions ended up with some partial port 'stuffing', but this information needs to be checked by going through past messages there. Anyway from REGs and Toms reviews it would seem that the Stirling LS3/6 manages bass control just fine without any port filling.
> --- In email@example.com, "kevingan3" <kevin.egan@> wrote:
> > Thanks to all for info on port straws--the nice thing about this tweak is that one can easily purchase both kinds to try for a grand total of 4 or 5 bucks...I can see that the rigidity of the plastic probably gives an advantage here.
> > In any case, I promise not to extol the virtues of aged wax paper over polypropylene--"I heard things on familiar recordings I'd never heard before!" Nor will I begin investigating straws made out of old growth birch or African ebony...