SMD DD-1 vs DMM tuning

[Jville140db]

Ok so Steve asked me to post the results I sent to him, Tony and Juan.

Basically in our shop for the past 6 years I have been taught to tune with a DMM to set amps. And since this is a common practice. We wanted to see how much different it was using the DD-1 in the same car with the same setup. One tuning method vs the other. So here ya go I have 2 cars we have done so far. I will post them separately. In both tests the cars were on a 15 amp charger during all testing phases. Enjoy!

Edited August 30, 2011 by Jville140db

[Jville140db]

First Test

The tunes on the amps were done as follows. The first tune was done with a DMM with the deck set @3/4 volume. You know the good old formula method. The second tune well that was clearly with the DD-1. So what we looked for was max spl on music at tuned volume. Maximum volume of tune. The last was temp of the amp after 15 mins of 3/4 volume of max volume based on tune. The amp used was an old 250.1 lighting audio bolt amp with 2 crunch 12's a stock dodge headunit with a single run of cca 4 ga and a cheap line output converter with no adjustment. So are results are as follows.

Tools used Smd DD-1, Craftsmen DMM, a digital inferred temp gauge and an epic 160 i know its not a TL but its just for comparison of overall SPL.

The vehicle is a 2004 dodge dakota extended cab with a sealed box and subs forward.

Spl was based in lower passenger side a pillar with the drive door open and all other doors sealed.

Base temp before any testing or playing 77.6F on both tests.

The first tune based on a headunit max volume of 38 we tuned to 28 roughly 3/4 volume.

We hit an Spl on music of 130 DB

after that we set the system to 3/4 volume of the max tuned which was 21 on the volume and let it play regular music for 15mins than measured the temp at the bottom heat sink of the amp which was 114.6F

So than we let the vehicle sit for 2 hour to let all the items cool and to let the the battery recharge. After which we retuned with the SMD DD-1.

So with the same criteria we set to work.

Well the head unit according to the DD-1 distorts at volume 21 so we backed it off to volume 20. Then proceeded with to tune the gain with the DD-1 which was now at 1/4 not 1/2 as it had been before with the DMM tune.

So then we tested max SPL with the same track as before at max undistorted volume which yielded a 134 on the meter. Thats a huge increase of course we were shocked.

Then we did the 15 min real world music test in which we set the volume at 3/4 well actually it was 16 out of 20 so 80% volume we ran the same tracks and at the end of the test the amp read a shocking 112.2F. So the amp ran cooler as well hmm.

so as I was checking voltage through out the 15 min test I noticed something with the dmm tune we would drop down to around 12-12.4 volts on most heavy bass tracks. After the DD-1 tuning it would fall between 12.5-13.2 most of the time being on the high end of that.

So to say the least the proof is in the pudding. The DD-1 does what it says it will and more. The amp ran more efficient. The subs were louder and on top of that the electrical didn't get nearly as taxed for the given output.

[Jville140db]

Second Test

Ok so here goes for the second SMD DD-1 official real world test.

So the Equipment and vehicle are as follows.

Vehicle was a 2008 Honda Pilot

Head Unit- KDC-BT948HD

Subwoofer- AudioBahn slim line AW1004J run @ 2 ohms

Speakers- Polk Audio Dxi6500 componants in the front and 650 Coaxials in the rear

Amps- SSL EV4-1600 and Polk PA880

Wiring and Electrical- Single Run of Kicker Z series 4ga batt to distrabution blocks and 8ga out from the disrabution blocks to the amps. Signal wires were Kicker X series and speaker wire was a combo of factory wire, kicker z series and install bay 9 wire.

Sub Enclousure- Sub was custom mounted in the factory sub location

Tools used

SMD DD-1

Craftsmen DMM

Inferred temp gauge

Epic160 for spl test I know its not a Termlab but it will show a difference in SPL for our purposes.

Ok so as before we used the same series of tests.

First tune was done with a DMM. We toook the headunits max volume of 35 and went to 3/4 of that which was 26. after that we tuned the amps using the good old ac volt forumla like in the previous test. Which gave us 14.4 volts @ 4 ohms on the 4 channel which should be 50watts. The mono was tuned at 24.5 @ 2 ohms as to not exceed the subs RMS of 300 watts. So after tuning was done the crossovers were set at 120hz @ 24db per octive and the sub amp at roughly 100hz @ 24db per octive and we ran our tests.

The max spl of the system on music was 112db.

The temp before tuning was 79.6 on the 4 channel and 81.6 on the monoblock.

After the 15 min music test @ 3/4 of max tune volume which was volume 20.

The temp was at 85.4 on the 4 channel and 101.4. on the monoblock.

So with this test I also recorded the starting voltage and the lowest voltage at any point during play of the 15 min test.

Which was 13.1 at the start and 12.5 at the lowest point during play.

So I also took note of where the gains were set on both tunes

The DMM tune was set at 1/3 on the 4 channel and at a little over 1/2 on the monoblock.

So after the DMM test we let the amps cool down and the battery recharge.

Than we went to work again with the SMD DD-1.

So in this test vs the last we found clipping through the amp instead of the Rca's like on the previous vehicle.

And we found that our max volume undistorted was at 33 out of 35.

So using the same battery of tests and the same music we set to find out what the DD-1 would bring to the table.

The max spl jumped up from 112db to 115db. on music.

The 15 min music test was up next so we set the radio @ 3/4 vol which was 25, and with the monoblock putting out more power I did expect a big jump in tempeture since the amp is rated @ 500 watts RMS and in the last tune we tuned to 300 watts RMS.

However the results of the heat test were rather shocking.

With starting temp this time of 80.6 on the 4 chan and 81.1 on the monoblock.

The 4 channel ran up to 85F which was a difference of 1.4F which was a lil cooler and the monoblock did run hotter as expected but it was only 102.2F thats a difference of 1.3F almost nothing given the amp was putting out more power in this test as seen by the spl result.

The voltage through out the test also revealed promising results at a starting voltage of 13.1 and the lowest at any given point was 12.8.

The gain setting moved as well in our favor as instead of 1/3 on the 4 chan we are now at 1/4 and on the monoblock we went from just over 1/2 to 1/3.

Edited August 30, 2011 by Jville140db

[tonedeaf]

Very cool side/side testing. Real tuning > DMM tuning.

[meade916]

great review! thanks for taking the time to write all of that up!!

[Jville140db]

No prob bro more to come stay tuned

[Twistedchild420]

Very nice job bro!

[RooTxBeeR]

Dude that is really awesome, I cannot wait to get one of the bad boys. My birthdays coming up on November 8th, going to try and get it from someone for my birthday.

[MrSkippyJ]

Posts like this are why as soon as I have the money this tool will be in my arsenal. The only bad things people say about it are ones who dont use it. All the people who use it rave about it! Can't wait!

[DaJuice]

Nice review. Good work