DD Audio 9518-SC-D2 Pulls 155.3dB!

As a lot of you know Ashley ‘MADBASS’ Burrell and myself have been doing SPL testing for the last five weeks in search of the 155dB+ with reliability, well it didn’t start as this but it surely ended that way.

Well it started as clamp testing so we could find where our SPL system was the most efficient so we could help do the same for a good friends car with a similar set-up, with this we not only tested the amplifiers to find where they were making the most power but also where they were netting the best result with the least amount of power. We noticed the sweet spot was with a lower volume pushing a significant amount of power less than we originally were to net the same result’s.

After that we started working on box positioning and port lengths, over the next several days we spent a good hour every night testing different placements of the box within the Toyota Vitz till we had covered every possible location with every possible frequency and port length too.

Now that we had the placement, volume & frequency sorted it was time to let the poor little Toyota Vitz have a well needed rest to give the batteries a good chance to be topped up again. This rest didn’t last very long though since the batteries only took twenty odd hours to fully charge & I had already started to get a little bit stir-crazy due to the lack of bass while driving. Ok, I’ll admit… I was going really stir-crazy from the lack of bass!

We now were at the point of giving ABTEC3 (Toyota Vitz) a good run for its money so to speak and see what we could squeeze out it with a SPL test. At this point I had Ashley asking me what my predictions were and I didn’t even want to speculate anything just in case I was way off.

So on went the laptop, Term-Lab and SPL Sensor and now it was time for me to double/triple check everything to make sure I hadn’t missed a thing while setting up the Head-Unit/Car. So Ashley checks the meters one more time, I select 57Hz, pause, wind the volume up to 25, check with Ashley one more time and BURP…

154.8dB… Now you must understand after all this testing, late nights and effort I was feeling a bit down like I had missed something important. You could say I was on the brink of giving up, but Ashley convinced me to carry on for a few more days and there was one more thing we had not done up to now… Sound Deadening!

So out came the SPL Box/Factory Tool Kit & Spare Tyre, off came the front door cards and George & Ashley got started preparing ABTEC3 for two packs of Dynamat to be installed while I manned the showroom. A few hours later and all the Sound Deadening was sorted and it was time to see if our results went up or if we had just ruined them.

So it was that time again to set up the Term-Lab/Car then BOOOOOOOM… Well to be honest it was more like a “mmmmMMMM” since the Dynamat had made a massive difference to the amount of sound that came out of the car.

Anyway I’m getting off track here… So the first result up on the screen and it took a second for it to dig in, it was a 154.6dB! My heart sank and I started to think the testing had not paid off but we were not finished yet, so we gave the trusty DD-9518-SC a quick rest before resetting the meters and trying at 58Hz. This time it dropped to a 154db flat, but then I remembered something a friend had said about Sound Deadening lowering the cars resonant frequency.

So I gave the DD-9518-SC  a quick Frequency Sweep to find if the sweet spot had been changed and to no surprises it had dropped 3Hz, so the next step was to test again @ 56Hz. I had to look again when I saw the display on the Term-Lab show 155dB flat, then again when it showed 155.3dB @ 55Hz!

Just to make sure it wasn’t a one off thing, we did another 155+dB two more times! And just after we packed up a good friend even turned up & asked us to set back up so he can film it, which we happily obliged! I must say I am pretty wrapped with getting a 155+dB (which has been my goal ever since I started Sound-Off’s) and even more wrapped that we have done it with One Sub-Woofer since this is a NZ First in my understanding!

This is slowly turning into a novel (again) so I’d like to thank Ashley for pushing me when I was ready to throw the towel in, Jassa and ALL of DD Audio for the help over the last year or so and for building such epic and beautiful sounding audio equipment! All of ABTEC’s friends, family and fellow work mates that have helped out in one way or another and last but not least Lauren my partner that has put up with my longer hours and moods when testing had us all moody and tired!

P.S. I think Ashley has the SPL bug again!