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Help me choose an 8
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<blockquote data-quote="PV Audio" data-source="post: 6413801" data-attributes="member: 554493"><p>Okay, FR plots to go around //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif</p><p></p><p>Ported:</p><p></p><p>ID8</p><p></p><p><img src="http://img194.imageshack.us/img194/1964/ID8ported.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p>Dayton HF-8</p><p></p><p><img src="http://img194.imageshack.us/img194/1845/daytonhf8ported.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p>Assassin 8</p><p></p><p><img src="http://img194.imageshack.us/img194/5408/ass8ported.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p>Type R 10</p><p></p><p><img src="http://img194.imageshack.us/img194/5126/typerported.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p>Sealed:</p><p></p><p>ID8</p><p></p><p><img src="http://img194.imageshack.us/img194/1093/ID8sealed.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p>Dayton HF-8</p><p></p><p><img src="http://img194.imageshack.us/img194/5348/daytonhf8sealed.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p>Assassin 8</p><p></p><p><img src="http://img194.imageshack.us/img194/2996/ass8sealed.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p>Few things to note: the type r has a slightly larger enclosure both ported and sealed which is merely due to the entire driver not fitting on the baffle used for the 8s. The ported enclosure is 1.18 gross for the 8s, for the R, it's 1.23. For sealed, the gross is .542 for the 8s, and not posted for the R, since I didn't even bother. There's no point in getting the 10 to just run it sealed. The only reason is because I can get it to fit in a small ported box, and a sealed ID8 or sealed Dayton will be cleaner anyway, so it's useless to me in a closed box.</p><p></p><p>Ported, however, the ID and the R look like absolute ***. I could bungee jump off the the ID and the R's FR plots. The F3 for the ID ported is 30.8, for the R 27.5 ( //content.invisioncic.com/y282845/emoticons/omg.gif.05aa02c3095d6ce9338996654eca0863.gif ) and for the dayton 48.5hz. The reason for the dayton's high roll-off frequency is if you can see, it has some gain above 0db to around 3, and therefore when it's a relative 3db down, it's only back to baseline. Its "true" f3 is actually about 29.5hz. Note, however, that the Dayton and Type-R are modeled as nearly Butterworth high-pass filters, while the Assassin is modeled as a Chebychev type 1 high-pass model. Why this happens, I'm not too sure, but the point is that I'm not too keen on its dip, espeically since it doesn't have the shelf-like roll-off of a Chebychev(1) filter.</p><p></p><p>The ID8, on the other hand, is almost exactly like a low order Chevychev type 2 high pass filter, and is possibly one of the most beautiful FR plots I've seen. With that said, it's the same reason why I don't believe it. Assuming there's some iffy parameters in the modeling, we'll ignore the FR plot above 100hz. If we do that for all of the alignments, you'll still see that the ID is ideally flat. Ideally flat in reality means something is wrong //content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif. Any ideas as to what it should look like? I can't believe it would be that flat down, then have a nearly linear slope. Not possible.</p><p></p><p>Any ideas or other drivers to look into?</p><p></p><p>-Dave</p></blockquote><p></p>
[QUOTE="PV Audio, post: 6413801, member: 554493"] Okay, FR plots to go around [IMG]//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif[/IMG] Ported: ID8 [IMG]http://img194.imageshack.us/img194/1964/ID8ported.jpg[/IMG] Dayton HF-8 [IMG]http://img194.imageshack.us/img194/1845/daytonhf8ported.jpg[/IMG] Assassin 8 [IMG]http://img194.imageshack.us/img194/5408/ass8ported.jpg[/IMG] Type R 10 [IMG]http://img194.imageshack.us/img194/5126/typerported.jpg[/IMG] Sealed: ID8 [IMG]http://img194.imageshack.us/img194/1093/ID8sealed.jpg[/IMG] Dayton HF-8 [IMG]http://img194.imageshack.us/img194/5348/daytonhf8sealed.jpg[/IMG] Assassin 8 [IMG]http://img194.imageshack.us/img194/2996/ass8sealed.jpg[/IMG] Few things to note: the type r has a slightly larger enclosure both ported and sealed which is merely due to the entire driver not fitting on the baffle used for the 8s. The ported enclosure is 1.18 gross for the 8s, for the R, it's 1.23. For sealed, the gross is .542 for the 8s, and not posted for the R, since I didn't even bother. There's no point in getting the 10 to just run it sealed. The only reason is because I can get it to fit in a small ported box, and a sealed ID8 or sealed Dayton will be cleaner anyway, so it's useless to me in a closed box. Ported, however, the ID and the R look like absolute ***. I could bungee jump off the the ID and the R's FR plots. The F3 for the ID ported is 30.8, for the R 27.5 ( [IMG]//content.invisioncic.com/y282845/emoticons/omg.gif.05aa02c3095d6ce9338996654eca0863.gif[/IMG] ) and for the dayton 48.5hz. The reason for the dayton's high roll-off frequency is if you can see, it has some gain above 0db to around 3, and therefore when it's a relative 3db down, it's only back to baseline. Its "true" f3 is actually about 29.5hz. Note, however, that the Dayton and Type-R are modeled as nearly Butterworth high-pass filters, while the Assassin is modeled as a Chebychev type 1 high-pass model. Why this happens, I'm not too sure, but the point is that I'm not too keen on its dip, espeically since it doesn't have the shelf-like roll-off of a Chebychev(1) filter. The ID8, on the other hand, is almost exactly like a low order Chevychev type 2 high pass filter, and is possibly one of the most beautiful FR plots I've seen. With that said, it's the same reason why I don't believe it. Assuming there's some iffy parameters in the modeling, we'll ignore the FR plot above 100hz. If we do that for all of the alignments, you'll still see that the ID is ideally flat. Ideally flat in reality means something is wrong [IMG]//content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif[/IMG]. Any ideas as to what it should look like? I can't believe it would be that flat down, then have a nearly linear slope. Not possible. Any ideas or other drivers to look into? -Dave [/QUOTE]
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