my Down4Sound custom box has been a nightmare of scrambled bass egg tuning, NEED HELP, ADVICE..

[missionman]

Ok so i was one the fools (safe to say now) that paid $800 for a custom box 1.7 cubic feet, tuned to 30hz. 30hz was my first problem. hold that thought.

Its loaded with a single American Bass HD-Velocity 10" 1ohm (2200w rms) sub wired to 2ohms. Powered by Taramps MD300.1 2ohm amp and dual AGM batteries and a new 140amp alternator, big 4 0AWG wire upgrade and 8 gauge speaker wire. My RCAs are Sundown Audio. They are good. Nothing is lacking here except my budget sub and amp.

I'm not new to tuning. My target voltage was 66 volts and tuned the frequency to 30hz. I abandoned all that. It sounds like CRAP. Less gain, it sounds like crap. It unloads A-LOT. I mean A-LOT. Not in the traditional meaning. it unloads even with trimmed gains so bad you cant even play certain songs. It clips when it sounds perfect so I have to always mess with the amp and unit on each song. SO ANNOYING.

If you've ever heard Crystal Method the Vegas album, that whole album sounds like scrambled bass eggs if you can picture that in your ears. Ive tried lower gains, i have no EQs on, no subsonic, filters are set correctly, i even trim filters to lessen unloading pains, I have a Kenwood DMX958XR and my X-over is more flat drop at 12% curve, -4db on, x-over set 30hz is not enough bass (stereo sounds isolated all the time), 40hz is WAY too much on x-over. I feel like im in jail dealing with sound here and there's no way but to throw it all out and start over.

there's literally no happy medium. it plays super boomy in few areas very close to 30hz and nothing at all anywhere above and below (-10hz/+10hz) sound good at all. tune it to 40hz on the head unit and then its over powering, yes even on lower gains. it is maddening. It unloads so easy all over the place. In fact only a few rock songs play ok. most everything else plays horrible. the response and resonance is horrifying. its like all the right stuff in the wrong configuration. ive tried EVERYTHING. I mean EVERYTHING. I even bought new triple insulated RCAs heavy gauge. I bought new wire. I soldered instead of cold crimped for less resistance. I battled every known issue. It comes down to my flawed box. I know its flawed. The design is rectangle to accommodate my car when its impeding on the sub and amp power. I did research and found that my sub has a wall too close behind the motor and this is causing erratic reflex which explains the constant resonance unloading where it normally doesn't unload in a properly designed box. meaning my box is too flat and depth is not enough. its squeezing the space in a way that causes the driver to fight itself as soon as it pushes power so the power and sound wave overlaps and you get sound waves crashing into each other. This is EXACTLY what my sub is doing.

Forget about a multi meter here. I tried all that. My targets are too high. So its been a constant battle to find anything that matches having a big box while lowering gains. makes no sense. I should have a smaller sealed box and a sub and rejoice.

I did have a HAWK 10" sub in it wired to 2ohms and it was the same. This HD-Velocity is even worse it seems.

Ive tried every damn method to make the sound equal out even sacrificing loudness. Ive always ran sealed boxes and never EVER had issues. Ive built them, bought them, etc.

MY PROBLEM:

I STUPIDLY dumped almost a grand into this box. I ordered it tuned to 34hz at first and then changed it to 30hz before production. I also requested a custom dimension to be able to fit in my 4runner under some molle panels I have installed. This was very ignorant but down4sound will do whatever you say without questions and they wont say anything to advise you unless your lucky that day. I cant blame them. they make great boxes but I can see engineers talking amongst themselves "man this guy doesnt know what hes doing". And they would be correct.

I NEED HELP WITH A SOLUTION:

The sub in it is for a ported box with no sealed recommendations so ill have to get a new sub....

I have 2 small travel size MyPillows that fit nice and super tight PERFECTLY in the port and plan to stuff 2 of these mini pillows inside the box at the beginning of the port to seal it artificially (eventually ill seal it permanently)  - but - this means I need to get a new sub I guess and i have another problem, sealing this box is like having too much cubic feet for a SQ sub. I'm almost wanting to sell this box for half or less the money and its brand new. Im not having any luck with tuning and there's no proper tuning this box for whatever reason. ive spent well over $3000 on my audio and arrived at scrambled bass. WHAT WOULD YOU DO? Is sealing this box with travel mypillows an option?

 

[Joe X]

Set your gains with a DD-1 or a scope, make sure you do an excellent job.

 

Then set your hi pass filter to 30Hz (or a little more) on the amp, any bass boost should be set to zero. Also the head unit and equalizers or whatever you have, all tone controls set to zero, loudness to zero and any other effects to defeat, make sure you do not forget anything.

 

That should get it under control, if you still don't like the sound after the fixes just sell everything, that kind of products are not made for sound quality.

[missionman]

Joe X, thanks for the quick reply! Unfortunately Ive done everything you suggested, many times over. Its not working. there is something wrong with the box.

I discovered that the rear of the magnet is nearly touching the wall of the baffle inside the box. Its due to my design request. which forced D4S to cram the sub space by placing the baffle almost touching it. In fact its got less than a inch of clearance and thats not recommended on any good box.  

I didnt use a scope but I did use a very expensive clamp meter that measures highly accurate AC/DC voltage, ohms and amps. its got a better accuracy than your harbor freight DDM.

I dont have any EQs on. I only ruin flat. I even run -4db on the sub and that helps but only on a few songs. I don't use subsonic or loudness, ever on amp or head unit. I strongly believe its the box design. Ive done what you said and cannot seem to eliminate the sub unloading all over the frequency space its tuned for.

 

Im going to try to seal the box and buy a different sub. I dont know what else to do. I know its not my amp or sub or settings. setting everything perfectly at target causes so much resonance distortion its unplayable.

This is the 2nd (better) sub in the box with same inherit issue. its behaving as if a air movement problem is occurring in the box.

It cannot play any sound unless its severely isolated. the minute a song blends any sound it just sounds like garbage. i have not been able to correct it any way including lowering gains, lowering Hz to around 27Hz but then it never plays any bass.

the engineer had his own dimensions and hole cut out and I changed them all to my preference. I admit this was not smart.

As you can see I asked the engineer to move the hole from the right to the left as seen in the rendering photos here. Another guy told me that was also a mistake because the box design required the hole to draw and push from the right where it had computer generated placement in the box. now its literally touching the baffle wall behind it in the middle not drawing equal air and its behaving EXACTLY as if this is the cause.

[All_Ears_On_Me]

$800 - D4S Custom Enclosure

1.7 cu.ft.

Tuned to 30 Hz

American Bass Velocity HD 10

Mounting depth 7.72

Recommended port box 1.8-2.5

 

Try inverting your sub and set phase to 180

 

30 Hz

 

LP 65

HP/Subsonic 20

 

No pillows, try Pollyfill 

 

Try adding another piece of wood to the baffle, just a square, enough to clear the sub and cutout.

 

 

[missionman]

HOLY crud I just found out the flipping reason everything has been sounding like crap. After months of anguish and hours today I find my Taramps high pass filter is reversed! something is wrong with the cheap dial on it. In a last ditch effort I began wildly turning dials the wrong way just to see the expected response and all checked out (even low pass filter) except the HIGH PASS filter which is the bass handling filter giving me messy insane sound/power.

I love Taramps power but I absolutely hate their freaking quality. I wouldve never figured this out had I not come here and tried some last ditch efforts.

I was frustrated beyond belief. I was actually going to buy another amp JUST FOR BETTER KNOBS. holy hell their knobs are trash.

Even after turning them they seem to be getting sloppier sensitivity.

 

by the way I tried sealing the box with 2 mypillow travel pillows and it sounded great but loss of power of course. I unplugged it and tried one last time before removing everything and buying new stuff.

Who wouldve thought a cheap plastic high pass dial was backwards. I assume its either damaged or it IS in fat backwards.

 

IT NOW SOUNDS AWESOME! totally night and day. THE FLIPPING KNOB IS BACKWARDS. thanks Taramps!

[missionman]

Im testing the high pass filter right now and sure enough 30hz is actually ALL THE WAY THE OPPOSITE WAY (clockwise 90 degrees) and all the highs are where 30Hz is supposed to be. WHAT THE HELL. What wouldve caused this. the dial cant be installed wrong so what would make it reverse?

By the way when I got this amp from South America brand new i took it out the box and several knobs were bent. I had to massage them somewhat straight again.

[missionman]

SOUNDS ABSOLUTELY GREAT NOW. LOUD, CLEAR. man im happy.

[All_Ears_On_Me]

Good job ! 

Sometimes we overthink shit, but happy to hear you're getting your results and thank you for sharing your experience.

[Joe X]

8 hours ago, missionman said:

Im testing the high pass filter right now and sure enough 30hz is actually ALL THE WAY THE OPPOSITE WAY (clockwise 90 degrees) and all the highs are where 30Hz is supposed to be. WHAT THE HELL. What wouldve caused this. the dial cant be installed wrong so what would make it reverse?

By the way when I got this amp from South America brand new i took it out the box and several knobs were bent. I had to massage them somewhat straight again.

 

It is more likely that the filter is out of range than reversed, say it tops at 35 Hz instead of 90Hz, that it should so to set to 30 Hz you need to go close to max of the range to get the 30 Hz, that is a common issue with taramps amps, very well documented and a high number of units will show this problem, that is for using cheap components with loose tolerance or maybe they used the wrong component value out of not having the right one at hand at the time of assembly. To keep cost down I am sure they have very basic quality control that only includes a turn on test and playing a tone to give the unit the green light.

 

You could have a technician to test and fix the tone controls but if you have the money get a better amp before a more serious fault shows up.

 

Glad to see your progress and that you did not need to spend a lot for a new sub/box.

[missionman]

Yes Joe I see what youre saying. This amp is supposed to be 10Hz - 90Hz tuning but the 30Hz is over where 60Hz is and 60Hz is over by 25Hz and on top of this the bass comes in and out (loud unexpected booms) periodically making it worse! the dial is definitely broken. Were taking it apart to see what the issue is. Previously this amp arrived new only with 3 bent knobs out of 5. i know the subsonic was slightly bent and the high pass was sharply bent. by bent i mean visually crooked and you couldnt even turn it without pulling in one direction to straighten it out.

 

Does anyone have a amp recommendation to replace this Taramps MD3000.1 2ohm amp? I want 2500-3000w rms on 2ohms.