Sundown dual SD3/Hybrid Audio audio build Q & A

Wiz - Bluffin

https://www.youtube.com/watch?v=YY6CJRGgVyU

My last and final enclosures were made from Baltic Burch. Had to go to a local woodworking shop to find it though. Still way easier to work with and a better quality of material to make enclosures with!

 

Here is quick video i made the other day. I feel like the subs should be 'hitting harder' than what they are. 600w RMS each and i feel like they have shook more shit in my truck than what they are currently doing.

https://www.youtube.com/watch?v=8VrBq4ZHVjU

 

They "bump" pretty good for being behind the seats lol. Perhaps what you are talking about is the like hit you in the throat hit? My sa's hit a little harder than that but they arent fighting with the seat

 

Yeah but i have had these subs play on 3 different amps now and i feel like i have heard them play louder. Maybe not, maybe it doesnt seem louder due to the door speakers keeping up with the loudness of the subs.

 

My next step is door speakers to keep up with my 12s. For me the 2 12s are a little much lol they get loud and for mid level 12a they are good

 

Yeah i thinking about stepping up to the SD3-12s. I think i can fit them in the boxes i have now, just need to cut a larger mounting hole. But im also afraid that the magnet will hit the back channel gap on the inside of the box.

 

Have you tried messing around with the crossover point and slopes between your subs and mid? I noticed you're overlapping your sub and mid - sub LP at 80 and mid HP at 60. Phase issues are much more noticeable at lower frequencies. I'm wondering if your mids playing that low is sucking out the bass from your subs.

My recommendation would be to try putting both your mids and subs at 80 Hz with a 24dB/oct slope on both. Also, I would take off any HP on your subs and let them naturally roll off.

Tuning can be frustrating, and a few times I wanted to throw in the towel, but I learned a lot in the process and saved $$$ I would otherwise give to a tuner.

 

Stepping up to the 12s will significantly increase your output. Personally id also give them more power.
I always use amps 2x rated the subs power rating. There is a reason, and a very good one but really not gonna get into it in this thread.

 

Going off of what manethon said since they are sundowns you can power them with rms plus half easily and still be fine. People run them at twice rns and they dont get warm.

 

I have seen sundowns, dd, and a list of other subs cook from a less than rated amp

I meant this in a general term, not based on Sundown for 2 x the rated power. There are many subs out there including our tritons that i do 2-3x rated power on for bass race, daily hard demo beats etc. ITs all about a clean signal. The Sd3 will do good on 1.5 rated power - 2 as long as its a clean signal.

If you want to look at it out of a technical standpoint you can always do burps/30 second bass race and clamp the output on the amp on the sub and make minor adjustments to the voltage and amps = watts exactly where you want it. It will compensate for impedance rise etc. Generally if an amp is wired at 1ohm and your rise is 3-4x which in these sealed boxes will most likely be so your sub will only see power at a 3-4ohm load rating. YEs impedance will change through the entire freq spectrum bla la la.... we know this but as an avg across it all you should be able to narrow it down pretty good

 

I understand the SD3 is the exception to the rule as Sundown and grossly underrated subs go. It has softer suspension than their others & the former will hit the back plate if it's pushed...so I've read.

 

Correct. Most Big time audio manufacturers under rate their subs

 

I will try it and see what happens.

 

Yeah i think the 12s would be more to my liking.

Talking to sundown on the phone they said that the SD series is the only series they make that they recommend staying in the rated RMS zone. Due to the soft suspension they are easier to blow. They said that 600w RMS was ok for the 500w RMS rated sub.

Setting the gains is really all i have done to the amps. I used the ohms law equation to find the amount of volts to set the gains at. For the subs amp i did 600w rms x 2 ohm load = 1200, then you take the square root and that gives you volts, in this case its... 34.64 volts. I did the same for my front stage amp also.

 

Doesn't that amp make 1200W@2 ohms? 1200x2=2400. Sq root of that is 48.99v.

 

What people don't understand, that I'm trying to point out is thats all good and dandy. That is setting your amp to be at a theoretic clean signal based on its rating.

Say you have a 2400wrms @ 1 ohm that does 1200@ 2 ohm and 600 @ 4 ohm
impedance changes throughout the freq spectrum but in general, do a few test on tones and look at the clamped power your actually getting out of your amp.

20/30/40/50/60 Avg your voltage and current scores. V x A will give you the RMS your sub is seeing

Now back to the 2400wrms example, Your subs are wired at 1 ohm. Most and i mean most setups have 3-4 x impedance rise. That means your 2400wrms amp thats wired to 1 ohm now is only actually giving the subs between 600-1200w due to this rise. Now if your wired at 2ohms, that turns into a 6 ohm or 8 ohm load.

Believe me, it makes a massive difference. I had 2 identical subs. One was d1.4 coils and the other was d.7
The d.7 coils i had wired at .35 and had a 3.2x rise which i burped a 149 db with
The D1.4 coils i had wired @ .7 and i was a 146.2db
Same box, same sub, same everything but the coils.

 

Boy howdy. I'm not sure how accurate this is, but it's WinISD's estimation of what's going on with my setup.

Apparent Amp Load:

Power (W) on the vertical scale and frequency (Hz) on the horizontal



Impedance

 

Yes, but let me add to it.
The amount of rise you get is some what related to various box parameters and inputs and is kinda unpredictable.
Even a simple ported box, has a range of rise lol. Its quite funny.

Build an amazing box, ready to roll, shit a 3.5 rise... well now i need new voice coils. Wait, lets rebuild the box its cheaper. Ah changed 1 small thing, 2.3x rise. Thats ok lets keep this one. ITs crazy.

Anyhow, not expecting anyone in this forum category to be going to that extent but its more for an understanding to not always Stick To the This amp makes 600Wrms at 1 ohm. Sure you wired 1 ohm but after that doesnt mean when the sub and music is playing the amp will see 1 ohm

 

@manethon how do you suggest setting the gains on my amp? I have a multimeter and a smart phone. haha

I have heard...

a. download a spl, use pink noise, HU @ 75% vol, turn gain up to 96db on amp

b. use the use math to calculate voltage output (explained previously)

c. use a 50hz tone with HU @ 75% vol, turn gain up till you hear distortion and back it off just under distortion

 

Id try find access to have O-scope or a Ddm-1.
Short of that, kinda how you have been doing it.

What i was referring to was simply illustrating the limitations of matching ratings