audiophile.1963 Posted December 11, 2005 Share Posted December 11, 2005 I examined two plans of La Scala and I see that the second part of the vent is more narrow (70 mm) than the first part (78 mm). In another plan there is a bigger difference: 64 mm/78mm. I'm not a technician but is It correct? An envelopement of an exponential horn usually increases?!? Giuseppe Quote Link to comment Share on other sites More sharing options...
djk Posted December 11, 2005 Share Posted December 11, 2005 The original was made of 1/2" stock, later changed to 3/4" but keeping the outside dimensions the same. I've made some wider to see if there was a difference, there isn't. Anyone contemplating building a LaScala sized horn from scratch and trying different drivers would be advised to make it a bit wider on the driver mounting board as not all 15" woofers are exactly 15" Quote Link to comment Share on other sites More sharing options...
audiophile.1963 Posted December 11, 2005 Author Share Posted December 11, 2005 So if I will make a cabinet with 70 mm or 64 mm (fixing 78 mm) It is the same? I calculated a volume for bass cabinet around 60 litres and I saw that the hole is 336 mm X 78 mm: is It correct? Remember that If I will build a bass horn I will use a K33. Thanks Giuseppe Quote Link to comment Share on other sites More sharing options...
Tom Mobley Posted December 11, 2005 Share Posted December 11, 2005 Giuseppe, be careful of the plans you are using. at least one set, usually seen in metric dimensions with notes in German, has a fatal flaw. the upper front motorboard has the large hole for the K-400 horn located too low. the lower edge of the hole needs to be at least 40mm above the bottom of the panel, otherwise the top panel of the lower section and the lower flange of the K-400 horn occupy the same space. Physics still doesn't allow this. Look carefully at the drawings you have to see exactly how these pieces fit together, make sure there's enough room for the horn flange above the top panel of the lower section. In mine, it was a tight fit to get both horns in, they almost touch. Good pictures of the interior of the top section will show this to be true. Quote Link to comment Share on other sites More sharing options...
Marvel Posted December 11, 2005 Share Posted December 11, 2005 This has been posted a few times, but attached is a pdf of driwings made by Jim Easley. Unfortunatley, they are in English measurements. However, these are very accurate, and may help you out. Bruce LaScala11.pdf Quote Link to comment Share on other sites More sharing options...
D-MAN Posted December 12, 2005 Share Posted December 12, 2005 The throat and side channel portions are the same exact width. DM Quote Link to comment Share on other sites More sharing options...
djk Posted December 12, 2005 Share Posted December 12, 2005 Depends on the year they were made. Quote Link to comment Share on other sites More sharing options...
D-MAN Posted December 13, 2005 Share Posted December 13, 2005 Point taken. So in the new 1" variety, are the channel widths the same - or is the overall cabinet dimensions larger to account for the added thicknesses? DM Quote Link to comment Share on other sites More sharing options...
Marvel Posted December 13, 2005 Share Posted December 13, 2005 Point taken. So in the new 1" variety, are the channel widths the same - or is the overall cabinet dimensions larger to account for the added thicknesses? DM The newer model is wider and deeper than the old model (assuming Jim's measurements are correct, and I think they are). Bruce Quote Link to comment Share on other sites More sharing options...
audiophile.1963 Posted December 13, 2005 Author Share Posted December 13, 2005 Pratically a little difference of few mm (70/64 mm) is not important ... but I don't understand why the horn is larger in the first part of the duct than in the second. Is it correct? At the end is it fondamental for the final result ... the sound? Or my drawing is wrong? I saw in a picture the new Klipsch La Scala II: with a cabinet of 1" (2,54 mm) I think that the woofer box should be built with a thinner material than 1"! Quote Link to comment Share on other sites More sharing options...
Marvel Posted December 13, 2005 Share Posted December 13, 2005 The drawing would be wrong. The first flare would go out, but the second part has no flare at all. The top and bottom of the cabinets are parallel and the two sides are parallel. This will also work in HF horns as well. But, the area at the end of the first flare is slightly larger that the area of the second part. Some models had them the same size, as in my next post, which in English measurements would be the 3 inches. Quote Link to comment Share on other sites More sharing options...
Marvel Posted December 13, 2005 Share Posted December 13, 2005 This is where the channels are the same width: Quote Link to comment Share on other sites More sharing options...
D-MAN Posted December 13, 2005 Share Posted December 13, 2005 Take it from me, kids, the side channels are SUPPOSED to be the same width as the throat channel width(s)... It is possible that you could not hear a difference providing it doesn't vary by more than 1/4 inch or so. This is probably a moot point in that the LS corners are left raw 90 degrees and that probably is far more detrimental to the sound than a slightly "thinner" side channel, that's for sure! Talk about reflections back toward the throat! But then look at the stock throat splitting wedge! What a JOKE! Might as well leave it out completely! It is far more of a support than a splitter. DM Quote Link to comment Share on other sites More sharing options...
Marvel Posted December 13, 2005 Share Posted December 13, 2005 Who you calling a kid? [] No, they should be the same but you won't hear a difference. Quote Link to comment Share on other sites More sharing options...
Joe Auwen Posted December 14, 2005 Share Posted December 14, 2005 Take it from me, kids, the side channels are SUPPOSED to be the same width as the throat channel width(s)... It is possible that you could not hear a difference providing it doesn't vary by more than 1/4 inch or so. This is probably a moot point in that the LS corners are left raw 90 degrees and that probably is far more detrimental to the sound than a slightly "thinner" side channel, that's for sure! Talk about reflections back toward the throat! But then look at the stock throat splitting wedge! What a JOKE! Might as well leave it out completely! It is far more of a support than a splitter. DM If one were to build a LS bass bin from scratch, what changes would be recommended to reduce the reflections? It would seem that 'rounding' out the corners would be a start. Would changing the size of the deflector help as well? Quote Link to comment Share on other sites More sharing options...
audiophile.1963 Posted December 14, 2005 Author Share Posted December 14, 2005 I could suppose, seeing the picture of the new La Scala II and considering the dimensions, that the thickness of the wood of the woofer box should be less than 1" or a lower distance in the second part of the horn otherwise where could be included a 15" woofer? Beppe Quote Link to comment Share on other sites More sharing options...
D-MAN Posted December 15, 2005 Share Posted December 15, 2005 If one were to build a LS bass bin from scratch, what changes would be recommended to reduce the reflections? It would seem that 'rounding' out the corners would be a start. Would changing the size of the deflector help as well? Use Huygen-described reflectors as attached. Also for splitting wedge at throat. Quote Link to comment Share on other sites More sharing options...
Marvel Posted December 15, 2005 Share Posted December 15, 2005 If one were to build a LS bass bin from scratch, what changes would be recommended to reduce the reflections? It would seem that 'rounding' out the corners would be a start. Would changing the size of the deflector help as well? If you 'round' the corners you will lose more high end. If you are going to do it, it would be better to make a hard reflection as D-MAN shows in the drawing. Quote Link to comment Share on other sites More sharing options...
jwc Posted December 16, 2005 Share Posted December 16, 2005 that's an interesting post as The la scala really doesn't have a flare. Bends at 90 gegrees. Dman, I have looked at you patent pictures and given lots of thought to the way the jubilee is built. I have pondered in my head a reverse La scala with 90 degeree bends Instead of the turns in the above designs. What implications would that have on sound jc Quote Link to comment Share on other sites More sharing options...
jwc Posted December 16, 2005 Share Posted December 16, 2005 For instance, this is built purely on 90 degree angles. I am only putting this here to make a point and understand something. What does this right angle deflection due to the sound? The La scala seems to work well with a 90 travel, why not a reverse la scala like a jubilee but with (2) 90 degree turnes. I know it would be best to flare the side panels but this was for a quick draw. Quote Link to comment Share on other sites More sharing options...
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