PODCAST: Do cardioid subwoofer arrays work underneath a stage? Posted on August 8, 2020 by ajhill - 1 Comment I recently sat down (virtually) with Nathan Lively from Sound Design Live to talk subwoofers, live event sound levels, audio signal decorrelation and Hunter S. Thompson. Follow the link below to listen to the podcast! Source: Do cardioid subwoofer arrays work underneath a stage? Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related Acoustics, Live sound, Research, Subwoofers New AES Technical Document published on outdoor event sound management 1 comment on "PODCAST: Do cardioid subwoofer arrays work underneath a stage?" Hi Adam and your research partners. I just wanted to say we agree entirely with your findings. We use 8 ASS B600 Sub bass enclosures on either side of our PA for use for music play out for Firework and laser extravaganzas. We use our own design and build of Bass, Mid and Top enclosures on top of the the Sub Bass cabinets. Ours is not a fancy high tech rig but we do run it as a five way cross over using two DBX Drive Rack crossovers on each side of the rig. When we first started using our rig we used to put the Bass Bins under the Bass, Mid, Top cabs using scaffolding towers and decking boards. When we first started to use the rig for events the first event event we noticed a “problem” was for a crowd of about ten thousand people at the Picketts Lock Sports Centre in East London for a fireworks and laser spectacular. We had the Sub Bass cabs located under the Bass, Mid, Top cabs using scaffolding towers and decking boards. On the sound check we were really unhappy with the bass performance of the rig. The bass was really low level and was sounding muffled and not giving us the clean punchy, sharp sound that we were expecting. We wondered if it could be due to the the fact that the bass cabs were in a confined space under the 3/4″ 8′ x 4′ decking separating the Subs from the “Full range” cabinets. During the sound check in the afternoon we were so unhappy with the rigs performance that we pulled the Subs forwards by about a meter and a half perhaps two meters out of the cavity they were in under the full range cabinets. We then re-time aligned the stack to get the phasing correct and ran the rig again. The sound on the second sound check was completely different from the sound on the previous run. We now had a clear.clean, punchy bass that was completely complementary to the rest of the rig. We now always run our subs a meter and a half to two meters out from under the scaffolding decking that elevates the rest of the PA and since then we have have had no issues with the overall sound that the rig produces. Ours is not an expensive rig, we are not using expensive amplifiers, we use BK electronics MOSFET amplifiers on the basis of one amplifier channel to one loudspeaker. We do use 6 DBX drive rack crossovers per side, two are live at any one time and one is left running as a hot standby in the event of a failure. Our Bass, Mid, Top cabinets are home designed and are based on a 15″ Bass driver (Eminence Omega Pro 15″), a 12 ” mid driver (Eminence Kappa 12″), a 14″ x 4″ Radial Horn using an Eminence 2002 compression driver with a pair of Fane HF250 bullet tweeters handling the top end of the HF. We did not chose Eminence bullets as I had previously used Fane HF 250’s on a previous rig and I was always really happy with the sound that they produced. We have been running the same rig for thirty years now and I am proud to say we have never blown a single driver! The bass and mid drivers are in ported sealed chambers in the cabinets and the horn and bullets are in a box at the top of the cabinet. I would be interested to see how our speakers perform in real life in the labs at the University of Derby when I do my Master’s Degree in Audio engineering at the university. studying under Adam Hill starting in September 2020. We hope to upgrade the rig over the next year to use 8 x Bishop Sound line array cabinets either side to replace or augment the cabs we already have. I will be interested to see what I learn on my master’s course to help steer us in the right direction going forwards. So to reiterate we fully agree with all the findings we have read about Adam Hills research into the placement of Sub Bass cabinets under stages or similar structures. We now ensure that our Subs are located at least one and a half meters forward of the decking supporting the rest of the PA and we time align the rig to get the phasing between the Sub Bass cabinets and the various elements in the full range cabinets as correct as we can get it. Best regards, Stuart Hall. MD at Lasergraph. Lasergraph@AOL.Com Reply Leave a Reply to Stuart Hall Cancel replyYour email address will not be published. Required fields are marked *Comment You may use these HTML tags and attributes: a, abbr, acronym, b, blockquote, cite, code, del, em, i, q, s, strike, strongName * Email * Website Save my name, email, and website in this browser for the next time I comment. Notify me of follow-up comments by email. Notify me of new posts by email. This site uses Akismet to reduce spam. Learn how your comment data is processed.