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Discussion Starter #361
That things A tank at 26lbs, well it's not bad but heavier than I care for , I shouldn't talk being im using 38lb 15s again.

I need to get this sub thing figured out. I'm so tired of pulling a 200lb sub box around ...


It sounded fantastic in the fact that from 40-120hz it had THE BEST bass I've ever heard in a car, it didn't get silly low but for an 18 it sounded like I had 30 8"s back there ... it was loud loud and blended with midbass way better than anything I've ever heard. It really had that pro audio sound and freakishly low distortion....I don't know if the box was wrong or if I just simply over powered it ... it didn't bottom out I fed it 1200w and gave me no indication that it was hurtn.

I started to smell what smelled like a can of band-aids on fire kinda I looked back and the whole back of my car was filled with smoke. I never seen so much smoke come from a speaker. And I've seen a lot of speaker blow....at work we purposely plug subs into the wall to field destroy them for warranty reasons and they never smoke like that one did...

On winisd it looked good, 5.5cu ported , tuned at 35 vent Mach 0.15 . it should have been all good ..

I definitely want that kind of sound , I had a ipal18 b&C a while back and I hammered on it and it never had a problem ... maybe it was defective, IDK
The recone is 80$ and another 50 to have them re-cone it , maybe I'll give it a 2nd try because it was light weight and great... kinda makes me sad

But when I stared looking into recone I noticed on eBay there's a holy shitload of them for sale and most of them are re-cones ....makes me wonder if a lot of them blow ppl recone them than sell them ... I would bet if you looked that sub up on eBay at any given time most of them on there are recones
Ho man you're pushing me to try with these comments.
I'm willing to, but I will first go ported with what I have.
Still not happy with my sub, the bigger volume didn't do anything.
Well maybe I should focus on tuning, but at the same step in the process I prefered the 4 tb 6" for example. Except output...
and since the box is now big enough I can easily cut few holes. With th gb first, then with what I have around.
Ported is a new world for me so I'll see.

I must try to measure my car resonance fr, and room gain to get a better idea.
But the peavey looks really flat, with an early drop compared to the gb but with cabin gain it might be good.
As I really enjoy the sub playing 80/100hz right now.
Lower is not that good.

Same or more impact, better details , that's what I need.
 

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So, as you read that thread , I thinking for sure I'll get the b&c that he posted up.

Kinda funny I been eyen that same sub for some time. At 500$ bucks a pop I'll have to sell the sundowns , and just to be clear the sundown sa subs are very sq and I think there overlooked by a lot of sq folks as being so sq ...

The sa subs are great for IB built strong etc etc , but after listening to the JBL I know I want a sub that's a little bit more like a giant midbass than a sub ,

The sound is kinda hard to describe, and I think I'm completely over using steep slopes for sub as well when a 1st order slope in FIR sq is one of the best things since sliced bread. Lol

You know how your midbass gets nasty loud (in a good way) at 100hz in a box?,
Having the sub play up into the 125 range where your HI-efficiency midbass start to loose umph is so nice , what I did was use a linear phase 1st order crossover at 50hz and some IIR eq to smooth the slope (Basicly a wide Q peak filter centered at 100 -5db) so that 90-350hz band that the sub plays audibly isn't dominant but gives a true backbone to the blend between midbass and sub...

Keeping phase right between sub and midbass is so easy because it's so audible when it's not right...and when it is right it reinforces all notes up to as high as 2-3khz..... it's like everything is vibrating together , the sub has so much surface area that even the tiniest movements of the cone make a difference.

To me that difference make things sound tight.... having upper Oactave bass info come from sub and the sub box having that low pitched ring to fill the harmonics of those upper bass notes is fantastic IMO and I like it. It makes kickdrums blend into the HF and everything else to have a very real experience as if the band is actually in the car with you playing live...

Having high order slopes on midbass and having to worry about having 10s in big boxes to do the job is sometimes just hard to do...

But it's not the only way to get there , like in your car you have a pretty good size sealed boxes so higher order slopes may work pretty decently especially that you have been the base upfront , I bet you could get away with not even having those big enclosures and have a very similar sound and just let the sub play up to those 125's or whatever , but the key is not letting the sub play at that height at full power it's a matter of blending using shallow slopes between Midbas and sub and getting the phase right between the two , and the cool thing at least in my case is with the 2 x 4 HD's and rephase I can dial-in whatever phase curve I want arbitrarily , so it happens very very easily . I bet DIRAC would do the job just fine to with a standard Butterworth's first-order applied in IIR.

I can get both the sundowns to play to 150, that's not the problem, I can just tell at 75-90 Hz most of the amp power is going to them with huge cuts at 50-60hz on eq....
And it leaves 55-65hz having a pretty noticeable distortion that is sluggish and garbled..

So
Anyway , I posted the sundowns on a local site , as soon as they sell I'm get the b&c
Pretty excited....:)
 

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Discussion Starter #363 (Edited)
Haha I always enjoy your posts, you put the right words on a lot of my thoughts.
The giant midbass instead of a sub, I think that's exactly it. Sure this blend makes everything even more dynamic and full, a nice complement to the horns.
The last 2 weeks I had this kind of tuning, even if I'm not 100% sure of why with my measurements, but I really liked it.
You're right now after few weeks of discovering the shallow slope thing, I think I could have gone with smaller.
Well the good thing is that they don't need much EQ on the first octaves, and I can still try to go lower later if needed.
Fullrange nearfields on midbasses were more like a 12db slope, and with cabin gain they look like a 6db or even less.
They played low with just enough volume and not much distortion, I'm sure it helped the blend and anchored everything in front.
And the sealed sub was easy to dial. By hand I could get a nice transition around XO but Dirac made it perfect on a larger band.

Although everything could sometime feel a bit "too" dry.
And I felt like I was still missing something on first octave. The sealed sub showed up well on measurements around there, but it was missing clarity.
And too close to my ear can be painful sometime.

So this week end I tried few things:
- first measured cabin gain, sealed box, top down/door opens vs everything close. It's a bit strange, it seems to build up after 65Hz but depending of the mic placement I can also have a dip around 75Hz so it's hard to define. I'll restart it
- same box firing backward, 2-3 inches of the back firewall > not bad at all, it acted like a low pass and worked well… until I pushed up a bit more and then the whole car went shaking like crazy! The box was well isolated so it's the output, the cone firing 70% onto the metal sheet. I tried foam/fiberglass/pillow etc on top of the grill to tame, nothing worked.
- 2 smaller boxes with 8", in different position "on" rear seats, opposed/front/up/back/mix of firing directions etc > no real gain, measured a bit flatter 20-60Hz, but less output and not much gain on quality.

So I modified the box to try ported. Played a lot with winisd, and with 600W while keeping excursion and air velocity down it asked for 6" port!
I started with what I found at homedepot = 4", about 80cm of pvc pipe with an angle inside.
Not much room there so the port is firing up, right side of the box.
I kept few inches outside so I could easily add the 4" cap, and too long inside to tune later.



But I must have messed up too much the simulation, maybe I under-evaluated the volume of the pipe taken in the box and over-evaluated the internal volume of the box to start with. Because it's tuned too low.
At least no rattles and that’s cool because I did it real quick.

Not much change compared to the sealed, it goes a bit lower louder but nothing dramatic. Too early to say if it's cleaner.
I'll play between 40-80cm inside, for a tune between 20-30Hz according to winisd. Flares and finish would be for later if I like it.



But, I wasn't able to tune as smoothly as before with the sealed. Around 100Hz I have a dip that I think wasn't there. Can it be the side port?
I didn't spend much time but so far I can't get my shallow slope back. :/

I only tried ported for a cleaner low end, not so much for more output I had enough I could get flat easily.
Maybe cabin gain is great in this case, but also maybe the soft top messes a bit the response?
That’s why I think one day I’ll try the peavey 15", in this small box it looks really good on winisd, smoother, and with the gain it should be closed to flat.
 

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Have you calculated the EBP?
The GB subs are mid Q no?

For some reason I thought you had a trunk, I see better now it's like a vw bug but smaller

Anytime I've used subs that close to me I try to go bandpass ,
Or shall I say give a bandpass box a try...
having subs that close you are very much in the range of motor noise, and I don't mean that v12 you have under the hood , I mean the subwoofer motornoise. Even the most quietest IB subs have a pretty large amount of noise ,it's non linear and it definitely adds quite a bit to the sound when your that close ..


A bandpass box will mask wall of that noise, but than you have the inherent downsides of a bandpass , but it doesn't always have to be worce , IMO the submotor noise would be worse than some group delay that for us is fixable

And I think some of the distortions that you measure from sub get a lot louder the closer you are to the sub, At least the ratios between frequency response and distortion response gets closer.. FME
 

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Discussion Starter #365
Have you calculated the EBP?
The GB subs are mid Q no?
No I didn’t, but just did :p
The Audiofrog T/S give an EBP of 32.5/0.52= 62.5
with mine measured I get: EBP of 26.92/0.66 = 40
I guess mine wants sealed


For some reason I thought you had a trunk, I see better now it's like a vw bug but smaller

Anytime I've used subs that close to me I try to go bandpass ,
Or shall I say give a bandpass box a try...
having subs that close you are very much in the range of motor noise, and I don't mean that v12 you have under the hood , I mean the subwoofer motornoise. Even the most quietest IB subs have a pretty large amount of noise ,it's non linear and it definitely adds quite a bit to the sound when your that close ..


A bandpass box will mask wall of that noise, but than you have the inherent downsides of a bandpass , but it doesn't always have to be worce , IMO the submotor noise would be worse than some group delay that for us is fixable

And I think some of the distortions that you measure from sub get a lot louder the closer you are to the sub, At least the ratios between frequency response and distortion response gets closer.. FME
Yep not in the trunk. Before in the coupe I had it IB.
Now the soft top once down goes in a big volume behind the seat, and over the fuel tank.
No easy way to use this area without blocking the top. + the tank doesn't help to vent anything in the trunk.
web pic:
p73113935-4.jpg
So I removed my rear seats (barely enough to sit 2 kids) and use what I have just behind, now the box is just sitting there (attached).
(but if I wanted to optimize, I could find more volume here, on both sides behind the panels, below to use the curves, and near the back wall. Maybe 2 more cu ft, with a lot of work)


I never noticed this motor noise, and I had it reverse mount for few weeks, literally at 2 ft of my head.
There's a vent on the motor, I could feel the air sometime, but not hear it.
But is it a specific noise or just added distortion?

I thought about trying a bandpass because I'm curious, the cheap one from JBL for example.
But can it play over a large band while keeping its main advantage?
Maybe I could build a bandpass "around" my back firewall, using it to separate both chambers…
 

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If you don't notice it than your not playing the sub anywhere near it max, which is good ...and ide imagine that's a fairly quiet sub to begin with...
That's no cheap sub either, like example a cheaper sub , the old w1s with gold cones...them were noisy a$$ subs ..

Point being , you said it was painful being so close to your ear...maybe I'm not thinking about the right thing :p

Are you talking about spl pain or noise pain from fatigue?
 

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Discussion Starter #367
It’s not the same pain as when my HF are too loud.
It’s much more physical, like I can feel the wave on the right eardrum on big impact, and less on left.
It’s very short, and I don't think it causes long term fatigue, and I didn't notice any loss.
Well of course usually it’s when loud, so everything will cause fatigue if too long.
I’ve never been to any SPL demo but it’s nothing like these crazy videos online with hair floating :D
So yeah it’s probably spl, but the fact that it’s not the same on both ears is a burden
 

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Oh okay I see now .... yeah that would be cumbersome

So hey , how do you have your 22d powered again?
You have the USB cord plugged into a USB to cig lighter adapter? And not using the 5v in?

How many amps does it need to be? I can wire up a relay and make it turn on with remote pretty easily , how do u think is the best way to power it?

Thanks
 

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Discussion Starter #369
Oh okay I see now .... yeah that would be cumbersome

So hey , how do you have your 22d powered again?
You have the USB cord plugged into a USB to cig lighter adapter? And not using the 5v in?

How many amps does it need to be? I can wire up a relay and make it turn on with remote pretty easily , how do u think is the best way to power it?

Thanks
It’s still a temp install right now but I had a free USB from this in on an AUX outlet in my dash, then USB to barrel cable and all good.
It wants only 600mA so really I didn't bother with remote etc and so far it’s clean.
Once I’m happy with settings (if ever) I’ll do a clean remote thing just for peace of mind.
 

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I'm doing a pair of the GB12's in about 3 cubic feet (could be smaller and still be just fine). They play very low and very cleanly. I was pretty surprised. Not the most sensitive subwoofer, but very good extension.
 

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Discussion Starter #371 (Edited)
I'm doing a pair of the GB12's in about 3 cubic feet (could be smaller and still be just fine). They play very low and very cleanly. I was pretty surprised. Not the most sensitive subwoofer, but very good extension.
Hum 2 GBs... I just modeled it and it looks nice, in my 2ish cu ft box they could play without HP and with a better response everywhere. Way less excursion at max power, maybe I should try!
And I could go stereo sub! :)
 

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One of my buddies here on the form as a GB12 on a hd1200/1 ,
Sealed Q.66
that thing gets seriously down for a 12 in a tiny sealed box
We had a nice meet and greet Diyma Rocky Mountain region style ,
Pretty dang good subs . If you get one I'll be pretty jealous
 

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Discussion Starter #373
Well mine doesn't go that low, measured sweeps down to 20hz yes, but with real music not that impressive. Even in the bigger box I had, with an hd750.
I'm in France now so didn't play much with my new ported box.
Once back I'll play with the port length.
Anyway I think I also have many issues to tackle:
- placement (center rear, firing front)
- not enough deadening and some panels vibrations in the rear
- maybe a need for little more bracing, or a complete new super solid box.

(but I still look at bigger asses... w15gti? :p)
 

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I'm really glad I saw you have that processor...
Man it's the best thing I've added. So thanks!

So when you take measurements do you have problems with it saying sub is clipping and are u forced to take really quiet measurements or have sub low when measuring?

I took a really quiet measurements and made a curve that follows the shape of the sub responce so that it wouldn't adjust the amplitude but just do a phase correction,

That seemed to work pretty good , but not having the sub up loud during measurements makes it hard to correct the sub phase with the extra 15db gain I usually like. So I took measurements with sub off and tilted the responce down at 50hz towards 20hz and optimize that way. Than added back the sub and measurement in REw than added sub back until it started pushing phase up than used phase eq to push phase back up so it's flat w rest of system.

Sub is so impactful now and thesesundowns I've been trying to sell actually sound good now. They can play barely to 80 at full power and rolloff . It's weird how this thing can fix the suckout at 80 by using sub and midbass phase and change it to reinforce 80.

80 is loud now and clear. I was really worried it would just boot into the null and just cause distortion but it sounds fine and plays loud without clipping.

Do you have problems getting measurement volume to ride at around 0db line all the way through the magnitude? I am loosing about -2 fb of signal and have to boost the input on minis by 2db to get all the signal back. I found the ddrc software has a level adjustment in it however I have mine a 0dbfs and just force Dirac to notboost. Wondering if you have similar experience

Anyway :)
 

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Discussion Starter #375
Back home!
I removed all drivers before leaving to keep the car driveable for my fellows, but I hope to have time to put everything back this week end and play with the sub.
I miss big sound!


I'm really glad I saw you have that processor...
Man it's the best thing I've added. So thanks!

So when you take measurements do you have problems with it saying sub is clipping and are u forced to take really quiet measurements or have sub low when measuring?

I took a really quiet measurements and made a curve that follows the shape of the sub responce so that it wouldn't adjust the amplitude but just do a phase correction,

That seemed to work pretty good , but not having the sub up loud during measurements makes it hard to correct the sub phase with the extra 15db gain I usually like. So I took measurements with sub off and tilted the responce down at 50hz towards 20hz and optimize that way. Than added back the sub and measurement in REw than added sub back until it started pushing phase up than used phase eq to push phase back up so it's flat w rest of system.

Sub is so impactful now and thesesundowns I've been trying to sell actually sound good now. They can play barely to 80 at full power and rolloff . It's weird how this thing can fix the suckout at 80 by using sub and midbass phase and change it to reinforce 80.

80 is loud now and clear. I was really worried it would just boot into the null and just cause distortion but it sounds fine and plays loud without clipping.

Do you have problems getting measurement volume to ride at around 0db line all the way through the magnitude? I am loosing about -2 fb of signal and have to boost the input on minis by 2db to get all the signal back. I found the ddrc software has a level adjustment in it however I have mine a 0dbfs and just force Dirac to notboost. Wondering if you have similar experience

Anyway :)
First times I used -10db on ddrc for safety, then quickly moved to -5db or more.
Tried many times at 0db and it was mostly ok, except very bad tracks.
Also I use a low target compared to measurements, so it mostly cuts.
I still have to play more with the gain chain To optimize.
Maybe there's a better way, but I didn't really mind I have enough power.

But no issue with the sub. Although I'm pretty sure my target is flatter than your. I must have 10db slope from 20 to 20k. And I optimized levels for this.
I don't know how much range dirac can manage.

No mic clipping as well. I don't remember the numbers but the sweep levels I used were just loud enough to be slightly agressive if too long.
But I want to try higher levels, just to check if it has any "loudness curve" impact.
 

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Back home!
I removed all drivers before leaving to keep the car driveable for my fellows, but I hope to have time to put everything back this week end and play with the sub.
I miss big sound!




First times I used -10db on ddrc for safety, then quickly moved to -5db or more.
Tried many times at 0db and it was mostly ok, except very bad tracks.
Also I use a low target compared to measurements, so it mostly cuts.
I still have to play more with the gain chain To optimize.
Maybe there's a better way, but I didn't really mind I have enough power.

But no issue with the sub. Although I'm pretty sure my target is flatter than your. I must have 10db slope from 20 to 20k. And I optimized levels for this.
I don't know how much range dirac can manage.

No mic clipping as well. I don't remember the numbers but the sweep levels I used were just loud enough to be slightly agressive if too long.
But I want to try higher levels, just to check if it has any "loudness curve" impact.
welcome back


So when I do my own measurements for tuning (not analyzing) I make them as loud as I can stand. About 100-105db . It alwaysmakes a better sounding tune . On Dirac it says I'm clipping and it isn't thatloud. (80db)

When I turn off sub I can run it up. Maybe I'll ask Dirac :)

I finally got a really good tune now tho. It works remarkably well
I had to set a good tune first
 

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Discussion Starter #377
welcome back


So when I do my own measurements for tuning (not analyzing) I make them as loud as I can stand. About 100-105db . It alwaysmakes a better sounding tune . On Dirac it says I'm clipping and it isn't thatloud. (80db)

When I turn off sub I can run it up. Maybe I'll ask Dirac :)

I finally got a really good tune now tho. It works remarkably well
I had to set a good tune first
100db! Ok I'll try higher then
 

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So in chair mode

Do you find yourself having to move the mic for the first measurement a wee bit to the right (towards the center of car) by about 3-4" from true center so the left isn't too loud ?

It seems to make the center more left because the level is a good 2db louder.


I have my first sweep about parallel with my right ear and it's perfect...
I'm 99% sure all the added energy the horns push to other side of car messes that up a tiny bit. Just wondering if you have same issue.

And before you said your measurements were a 2' square, so in chair mode do you put mic inpassanger area at all?
 

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Discussion Starter #380
So in chair mode

Do you find yourself having to move the mic for the first measurement a wee bit to the right (towards the center of car) by about 3-4" from true center so the left isn't too loud ?

It seems to make the center more left because the level is a good 2db louder.


I have my first sweep about parallel with my right ear and it's perfect...
I'm 99% sure all the added energy the horns push to other side of car messes that up a tiny bit. Just wondering if you have same issue.

And before you said your measurements were a 2' square, so in chair mode do you put mic inpassanger area at all?
Ho man I tried to find some old posts about that, because yeah I did try and I thought I typed why, I wanted to be sure I remember why exactly. Well I think it was more about my left boundary, I wanted to extend a bit. The center itself has always been easy to define and awesomely precise.
So yes I tried the mic 1/2/3" on the right, from right eye to ear.
And I didn't like it. In all cases the center moved way too much without improving total width or distribution.

But consider I have a specific dashboard, almost like a truck one, strong reflective (varnished wood) and vertical surface on all width (even if I believe the smooth curve under shape helps a lot to get quick good results).

For example with my old cones in pillars, I had a deeper and a tad wider stage, but with a much weaker center.
With horns I lost some of this, but gained so much everywhere else than it's a no brainer. :p

But, there's always room for improvments right?
I was studying some install pics lately, I think I’ll try again to push the horn more to the left. By reversing them I should gain 1", by cutting I could get more...
Was also considering some other cars that could fit some 10/12" in kicks. Maybe next one.
(For ex my oldy would be great for that. Could fit 12" in front wings, with high horns way into the engine bay... but no way, I wouldn't be able to hear them anyway :D)

And for the 2ft square cube, nope I don't go in the right area volume. I'll try to draw the points on some pics.
I have my visual references now to replicate easily.
 
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