monacor sp60x bib

[giantstairs]

i found that my local electronics supply has these drivers for a good price and picked up a few pairs.
i am planning to build a pair for me and a pair for a friend with an attic apartment.

while zilla's site was down i played around a bit with gm's simple formula and, if i did it correctly, came up with dims quite a bit different from those on the site. i got a length of 113 inches and a mouth area of 66 sq inches as opposed to a height of 128 and mouth of 55 sq inches. which would you suggest i go with?

the one for my friend will be folded 3 times, downward firing, to fit in the corners where his ceiling drops down to 36" (91cm).

mine will be used to replace my fe108ez bibs in my 75 sq meter studio so i am looking for a "larger" sound. i am toying with the idea of using 2 drivers per bib but am not sure where to locate the drivers. perhaps one on the front and another on the side might sound good but don't think it would fit at the same driver distance. gm suggesting using something like a tapped horn in another post but i'm not sure how this works. any suggestions?

[peterbrorsson]

Hi!
These dim's you calculated are almost spot on to my SPH bib's.
Height: 112
Mouth: 50

I built also the bigger one, on Godzilla's site, for a friend and it had a tad more bass but I didn't compared them in my room so....
As mentioned before in this monster thread, I suspect bib's are quite forgiving concerning box size. In reasonable range of course. Whatever that means

Good luck
Peter

[zek]

BIB sim on Zilla site are 128" lenght - not height, and for Fs~53Hz, not 60Hz as stated in Monacor data sheet

[peterbrorsson]

Hmm, I'm obviously not at the sharpest today!

Lenght: 112
Mouth: 50

Cheers
Peter

[giantstairs]

Originally posted by zek
BIB sim on Zilla site are 128" lenght - not height, and for Fs~53Hz, not 60Hz as stated in Monacor data sheet

yeah, i meant length... and using an Fs of 53Hz I get something very similar to the dims on the zilla page: line length of 128" and a mouth area of 58.5 sq inches. which Fs is more realistic?

peter, as you say these boxes are pretty forgiving and the different in size probably won't make much of a difference. i just want to make sure i end up with a "full" sounding speaker as my fe108ezs are a little lean in the bass.

any thoughts on the 2 driver bibs?

[Scottmoose]

Neither Fs is more realistic per se -it rather depends on what you measure your own units at. Sample variablility & all that sort of thing.

The suggested dims on Zillaspeak are just that -suggestions from which you take your exploration further. Some deliberately went for a longer length, some are on the ~ideal, some deliberately compromised for room / size reasons etc. If you want extreme, the SPH-60X will actually work quite acceptably in TC's original box with a ~140in flare & Sl of 55in^2. In the case of this unit, I suggested pushing them a little harder than some, as they've got sufficient excursion & LF performance to handle it.

All the different potential versions will sound different. If you've got a few drivers, why not try building a couple of different types, and see which works best for you, in your room?

[hm]

Hello,

my solution would be the small POSAUNE,

Front SPH68x, in the back invers SPH60x
easy to built.

[giantstairs]

hi scott,
glad you chimed in. birch ply is a bit dear here and i wanted to get the "right" dimensions but i understand now that "right" depends on individual drivers and room conditions. i do plan to build at least 2 sets as i have the drivers and should be able to do a comparison by the summer. i'm curious to see if the one with the extra folds has less hf leakage out the mouth.

any ideas in regards to a tapped horn version?

hm, thanks for the suggestion and a nice looking design. however, as easy as it may be to build it is still way beyond my woodworking skills. i don't have the facilities to do mitres so i'm stuck with right angles for now.

[Scottmoose]

I was hoping no-one would ask about a tapped horn version.

The only software I know of that can model a tapped horn is AKABAK, which redefines the term 'user-unfriendly'. I've fooled with it a little, but it's a major headache, which is only compounded by the fact that there's another driver in there too. Driver position depends on the line length, Vb, the other driver (to an extent) etc. For the 64in tall version, I'd guestimate an offset of ~12in down from the top, but don't hold me to that!.

[giantstairs]

Originally posted by Scottmoose
I was hoping no-one would ask about a tapped horn version.

well, someone had to do!

forgive my ignorance but it seems that placing a second driver firing down near the beginning of the horn would amplify lots of hf. is there some sort of filter involved? what does the addition of the second driver theoretically do to the sound?

alternatively, is placing a second driver on the side, at say .4 line length (at which point it may fit), a good idea. after seeing your calhoun design i thought it might boost the performance of the BIB.

thanks for humouring me and helping me find these drivers a nice home.