Reply to thread

Message

<blockquote data-quote="Art Welter" data-source="post: 132051" data-attributes="member: 52">Re: Sealed vs. Ported Subwoofer Enclosures in Pro AudioAnd worth every dollar/euro/whatever.As you have already noted, BR (bass reflex) has a 5 dB or so advantage over sealed, so you need twice the amplification and drivers to make up for that difference. Going from BR to a TH (tapped horn) design gains another 6 dB.&nbsp; The TH has to be slightly larger than the BR, so one still can achieve slightly higher output density (SPL per truck volume) with BR over TH, at the expense of twice the drivers and amplifiers.This horn has standard truck integers and is as easy to build as a BR using the same two drivers and the complex porting needed to eliminate port compression at the displacement levels the BC18SW115-4 can effortlessly provide.<a href="http://www.diyaudio.com/forums/subwoofers/185588-keystone-sub-using-18-15-12-inch-speakers.html" target="_blank">http://www.diyaudio.com/forums/subwoofers/185588-keystone-sub-using-18-15-12-inch-speakers.html</a>The Lab 12 was a real achievement a dozen years ago (or was it 14?) but in terms of linear response and power compression, the BC18SW115-4 is hands down the clear winner for output density. That said, a pair of Lab 12s are more sensitive (more output per given voltage) than one BC18SW115-4, so if you don&#039;t need the increased SPL the BC18SW115-4 can provide due to far better thermal management (and greater Xmax/Xvar), it still is a cost effective option. However, cost effective comes at a weight disadvantage...In the picture below, taken on my last gig before &quot;retirement&quot;, there are 32 eight inch speakers (28 horn loaded, 4 BR center fill) and ten 3&quot; diaphragm HF drivers above 2 single 18&quot; Keystones.&nbsp; In spite of suffering from food poisoning, Jason Raboin had a really nice mix going on just the second day of the LSD tour, and the rig had 6-10 dB headroom available, just loafing along. Very nice memories from that show, great to hear a group of young (relative to me;^) musicians and sound engineers &quot;doing it right&quot;.Art</blockquote>

[QUOTE="Art Welter, post: 132051, member: 52"] Re: Sealed vs. Ported Subwoofer Enclosures in Pro Audio And worth every dollar/euro/whatever. As you have already noted, BR (bass reflex) has a 5 dB or so advantage over sealed, so you need twice the amplification and drivers to make up for that difference. Going from BR to a TH (tapped horn) design gains another 6 dB. The TH has to be slightly larger than the BR, so one still can achieve slightly higher output density (SPL per truck volume) with BR over TH, at the expense of twice the drivers and amplifiers. This horn has standard truck integers and is as easy to build as a BR using the same two drivers and the complex porting needed to eliminate port compression at the displacement levels the BC18SW115-4 can effortlessly provide. [url]http://www.diyaudio.com/forums/subwoofers/185588-keystone-sub-using-18-15-12-inch-speakers.html[/url] The Lab 12 was a real achievement a dozen years ago (or was it 14?) but in terms of linear response and power compression, the BC18SW115-4 is hands down the clear winner for output density. That said, a pair of Lab 12s are more sensitive (more output per given voltage) than one BC18SW115-4, so if you don't need the increased SPL the BC18SW115-4 can provide due to far better thermal management (and greater Xmax/Xvar), it still is a cost effective option. However, cost effective comes at a weight disadvantage... In the picture below, taken on my last gig before "retirement", there are 32 eight inch speakers (28 horn loaded, 4 BR center fill) and ten 3" diaphragm HF drivers above 2 single 18" Keystones. In spite of suffering from food poisoning, Jason Raboin had a really nice mix going on just the second day of the LSD tour, and the rig had 6-10 dB headroom available, just loafing along. Very nice memories from that show, great to hear a group of young (relative to me;^) musicians and sound engineers "doing it right". Art [/QUOTE]

Verification