Posted by Tyler Jolley on Feb 7th 2015
How to unlock MORRR DB's:
Lots of guys getting in on the SPL LAB pressure sensors lately,
so I figured we would do an article on how to find more db's.
First off, I would like to note, one of the easiest ways to sustain higher voltage and it reflecting on the dash is runs of power wire. (given all grounding is on par) A local and prior world champ who was part of TEAM DB DRIVE was running 10k RMS in his van. One day he decided to do runs of power wire front to back (from the heart of the electrical system, under the hood) until he quit getting gains on the meter. On that 10K rms setup he stopped getting gains on the dash at 32 runs of wire, yes thirty-two runs. Due to being able to transfer power with nearly no resistance, he gains tenths of volts which turned into tenths of a DB, he finally found the end the possible gains using only power wire.
Now the list of things coming up are simple and free tricks that will allow you to utilize your SPL LAB Meter www.db-meters.com and squeeze out every possible db of your current setup without spending any money. These steps will show you the value of your meter and have you spot on prepared for when you hit the lanes this upcoming season. *Note- these steps will apply for sealed up to midwestspl style so if you cant do something per class, dont include it in your list of things to max out your db's in the lanes. *Note 2- in between burps, you must allow your woofers/ amps to cool back down, and electrical to catch back up. You will notice if you do a burp at the same volume every 30 seconds you'll lose a tenth or 2 each time due to the woofers getting hot ect.. this is important. *NOTE 3- CHARGE YOUR BATS. You can have 10 alternators and still need to charge your batteries to get them to 100% capacity.
First well known step you'll want to get out of the way is finding the resonance of your vehicle. Do a sine sweep at medium volume with the SPL LAB on peak hold. This will give you a rough idea of where your vehicle's peak HZ is on the dash. Lets say it peaked at 40hz on the sweep. Now burp 40, cool down, burp 41, cool down, burp 42 keep going up the frequency range until you find the frequency that you cannot beat in score. Ive found in most all vehicles that after running a medium volume sweep the peak hz ends up being a few steps up from this at full tilt.
Now that you have found your peak frequency and have achieved what would be your best score, its time to start finding every DB your vehicle has to offer.
All vehicles are different so each step may or may not increase your score but you'll find gains testing these tricks.
*rev motor to 1800 rpm and hold, this will get all of the current out of your alternator. Higher voltage=more tenths
*Floor mats- removing carpeted floor mats from your vehicle can be a simple way to see nice gains in the dash. I've found that rubber floor mats *CAN* help depending on the vehicle. But getting the carpeted mats out of the vehicle is 9 times out of 10 a quick and easy gain.
*Air vents- opened or closed
*center console- opened or closed (ive seen 2/10ths from opening the center console.
*visors- flip them all the way down, test both sides.
*seat positions- this is a long drawn out one but adjusting the 2 front seats in certain ways based off of your vehicle you'll find more.
*glove box opened or closed
*door, in midwest spl classes, you can use doors and crack windows, seal up all your windows and open the drivers side doo to different positions, you will find a sweet spot at a certain spot where you get the best dash reading.
*windows again long drawn our process but cracking windows one at a time has shown gains on certain vehicles even while using the door method.
*trunk - if you have a firing forward setup that is not sealed off, cracking the trunk at different positions can do WONDERS for increases. We tried this on a VW bug 2 weeks ago and gained 2 db, (legal in midwestspl)
*SUV's lower your rear seats flat. Seen multiple vehicles gain on this.
*Enclosure positioning- if your box is movable, test the position of your enclosure. If your firing on a rear hatch or trunk the distance the sub has to load off its firing wall can add up to db's when you find the sweet spot.
There are many more tricks but heres some to get you started. testing everything listed allowing cool down time in between is sure to keep you occupied for a couple days.
Good luck, and let us know what you find testing these methods.
~TEAM GP www.GPcarAudio.com
All prices are in USD