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Discussion Starter · #1 ·
My system info is in my signature. I started building this system back in October, I finished the system in April by switching to a 3 way front stage, tune was performed on my JL TWK 88 by a local shop. My midranges (CDM 880) were installed in Valicar pods on the a-pillar's along with the Supremo Piccolo tweeters. Front stage is powered 100x6 using a Mosconi One 100.6.

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Sound from the front stage was fantastic and clear and loud - for 3 months - but distortion had begun at the voice level, becoming worse over a few weeks, it was obviously coming from the midranges. After removing the RCA's and testing each speaker on various tracks, the passenger midrange is blown and the driver one is not far behind. After a week of thinking about it, I decided to order the beefier, more expensive MM3's as a replacement (these come from the Carbon and higher Morel line), I also ordered a new set of Valicar pods for the larger midranges, they haven't arrived yet.

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Here are the specs of both speakers. The MM3s are wider, deeper, much heavier and have a much wider frequency response:
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The CDM-880's were crossed @ 450 to 2500hz. Since I have read that the Valicar pods only play down to 400hz, I am going to start there once the MM3's are installed. I'm not sure if I'm going to have this tuned right away, get a remote tune, etc? I am a tuning novice.

I'm showing my ass here, a lot of people reading this are thinking I am an idiot or am throwing money away - that's fine. I think I am simply playing my music too loud, perhaps the CDM-880's couldn't play loudly at the upper midbass range around 400hz, I'm not really sure. I wasn't distorting them - not that I could hear, I never went above 52 on the factory H/U volume (it goes to 62 max). I've spent a lot of dough on this system, when my CDM 880's went out, I knew I was going to replace these midranges one way or the other. I am a big fan of turning repairs into upgrades. For what it is worth, I wish the CDM's lasted much longer, I got an unbelievable amount of enjoyment out of them for a little over 3 months.

More to come as I get the MM3's installed...
 

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with an Fs of 400 Hz and a 400 Hz crossover, you were beating the ever living **** out of those domes. a good starting point normally (depending on many factors) is a crossover point of 2x Fs, or in the case of your dome midranges, about 800Hz. at resonance the cone moves ... at resonance. in other words, it moves with great ease with minimal input. this is related to the tuning. domes can sound great, but this was doomed (domed?) to failure based on your settings. i'd tell the shop that tuned this to compensate you for ****ing this up.
 

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Discussion Starter · #3 ·
Thanks for the info. Yeah, I was thinking the domes were played too low and had heard the thing about doubling the FS value. The shop I used - I won't throw them under the bus - are the "premiere" shop in the area. They won't compensate me and I wouldn't ask, they are not a Morel dealer.

Actually, since you mention it, someone high up at Morel actually gave me the crossover points to use based on my equipment, I had screenshot' his email and passed it along to the shop when the tune was done back in April.
 

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2 things.

1) I agree with Vactor. Dome midranges shouldn't be crossed below 800hz or so. I personally so not understand why they are a thing in car audio.

2) people, please stop sticking your midranges in these Itty bitty enclosures. Every speaker, not just subwoofers, has an enclosure size requirement. It's more flexible when crossing above FS, but this small when it calls for IB is too much.
 

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i went from DLS gothia soft dome mids to Morel mm3.Had the DLS crossed at 400 and blew them, and like yours they were not distorting , but playing loud and clear when they went out. I like the morel but went back to DLS (after getting lucky and finding a set on marketplace) but crossed over at 480Hz and a little less power they have held up. I have not used the Morel soft dome so i cant compare to my setup, but the vocal presence and subtle details that i can hear made me stick with the soft dome mid.
 

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Discussion Starter · #6 ·
Every speaker, not just subwoofers, has an enclosure size requirement. It's more flexible when crossing above FS, but this small when it calls for IB is too much.

While you are on the subject, how do I determine the enclosure requirement for these?
 

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While you are on the subject, how do I determine the enclosure requirement for these?
The same exact way you determine the correct size enclosure of any speaker. You can model it to see what works.
 

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While you are on the subject, how do I determine the enclosure requirement for these?
Winisd is the program you can use to model speakers. Can you mount them in the dash corners pointing into the windshield? And I mean without the pods. OEM location? Or even kicks would be better. You have nice equipment (wish I could get MM3’s to fit!), don’t let the install be the weak link.
 

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I have CDM 88 / 700 / 880 all on my shelf and have tried all 3 in my WK2 because I'm a dome fanatic at home but it simply doesn't work out in the car - still trying to wrap my head around the why's and if the dispersion is just too much or too much directivity but it really gets wonky at times and it's different from one song to the next so I can never nail it down. On axis, off axis, direct, reflected, they all have problems and it gets really frustrating to think you have finally nailed the location only to skip to the next song and be totally bamphoozled by what you hear... You would think that adding a dome midrange between a 6x9 midbass and a 1" tweeter would be a revelation but it simply was not the case and I've been flogging that horse for over a year now (definition of insanity I suppose) with no success.

With that being said - I also concur that you had them crossed WAY too low and without enough airspace. I've pushed mine with a JL Slash 300/2 till dome breakup during my testing and always with them crossed at Fs x2 or greater and they are still performing admirably. But the MM3 is a totally different animal - I've only used them in Micro Monitors but when ported they are virtually flat to 300Hz but if you put them in pods... oh dear:

For reference - volume of a sphere is 4/3(Pi)(r^3) so a 3.5" sphere is 22.45 in^3 then cut off one third for the driver mounting flange = 15 in^3 then if we take the mounting diameter of the MM3 and the mounting depth as the volume - 10% that comes out to 11.6 in^3 so subtract that from the 15 and you're left with 3.4 in^3...

Blue Sealed is 9.9 cubic INCHES (remember we're dealing with a 3" midrange here - inches)
which yields an F3 of 268 Hz without any electrical HP...
Green Ported is 15.1 cubic inches at 138.24 Hz
Red Sealed is 3.4 cubic inches (my SWAG at about what those pods are and it could be much worse)
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Then add a 400Hz LR4 HP to the each of them... and you effectively have a 36dB HP at 500Hz.
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Running a midrange in the proper volume or IB is critical in getting the proper transition to your midbass.
 

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Is there a trick to isolating the backwave when mounting in narrow, shallow a-pillars? Just build up the backside so that it's fairly close to the surrounding surfaces, seal it w/ closed-cell foam and vent into the dash? Super narrow a-pillars in a old-style XJ Cherokee and trying to fit 3" mid up there... Haven't really seen "sealing the backwave" discussed much for a-pillar builds, but maybe I just missed it... Or am I overthinking it?
 

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Is there a trick to isolating the backwave when mounting in narrow, shallow a-pillars? Just build up the backside so that it's fairly close to the surrounding surfaces, seal it w/ closed-cell foam and vent into the dash? Super narrow a-pillars in a old-style XJ Cherokee and trying to fit 3" mid up there... Haven't really seen "sealing the backwave" discussed much for a-pillar builds, but maybe I just missed it... Or am I overthinking it?
It all depends on the gaps involved and how rigid your pillars are and how much pressure your driver will create... CCF, Butyl Rope, Weather Stripping, expanding foam - there are any number of ways depending on the goal and the airspace requirements.

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a good starting point normally (depending on many factors) is a crossover point of 2x Fs, or in the case of your dome midranges, about 800Hz.
Dome midranges shouldn't be crossed below 800hz or so. I personally so not understand why they are a thing in car audio.
i went from DLS gothia soft dome mids to Morel mm3.Had the DLS crossed at 400 and blew them, and like yours they were not distorting , but playing loud and clear when they went out. I like the morel but went back to DLS (after getting lucky and finding a set on marketplace) but crossed over at 480Hz and a little less power they have held up.
No experience with the Morels but the best sounding system I put together was with the DLS Ultimate Iridium 6.3. Is that the same dome mid as your Gothia? Running active 24/db slope I ran those down to 400Hz for years. I still have them, I'll get them installed again eventually. They have an FS of 280Hz so the "doubling FS" rule of thumb doesn't quite apply. Perhaps I lucked out because I was only feeding them 40 watts from a DLS A8?
 

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Discussion Starter · #15 ·
^Been busy with work, will be reading the above comments, for now here is a brief update:

I received the Valicar pods this week. It took a few weeks to get them, but they look great.

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@SkizeR, I did measure the volume of one enclosure using water which is roughly 2 cups, or 28.875 cubic inches:

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Unfortunately the swivel ball joint set and mounting thread piece for the old midranges is too small for the MM3 pods, I can't finish the install right now. I couldn't have known this and lol at trying to communicate, the guys english is not great. I just ordered the new swivel ball joint set, who knows if it will take a week or 3 weeks.

Also, the drivers side pod might not fit because of the hump on my dashboard above the steering wheel. These new pods are roughly 20% larger than the old ones. I won't know for sure until I get the new swivel ball joint set.
 
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^Been busy with work, will be reading the above comments, for now here is a brief update:

I received the Valicar pods this week. It took a few weeks to get them, but they look great.

View attachment 344355

@SkizeR, I did measure the volume of one enclosure using water which is roughly 2 cups, or 28.875 cubic inches:

View attachment 344356

Unfortunately the swivel ball joint set and mounting thread piece for the old midranges is too small for the MM3 pods, I can't finish the install right now. I couldn't have known this and lol at trying to communicate, the guys english is not great. I just ordered the new swivel ball joint set, who knows if it will take a week or 3 weeks.

Also, the drivers side pod might not fit because of the hump on my dashboard above the steering wheel. These new pods are roughly 20% larger than the old ones. I won't know for sure until I get the new swivel ball joint set.
Executive Summary = that airspace will work fine for the MM3 - aim for ~220Hz LR4 HP.

According to WinISD: MM3 "wants" 54.9 in^3 for Qtc = 0.691 which hits xmax at 221 Hz on rated 120W.

Going to 28.875 in^3 results in Qtc = 0.830 and moves xmax to 231.85 Hz on 120W.

Either one requires a 150Hz LR4 HP to run rated power and stay below xmax (3mm).

Even if you run them ported at 28.9 in^3 at 180Hz (1.5" x 7.65") the F3 is still only 158.53Hz...
So double the Fs at 172Hz starts to make sense... but since you're planning to do 400Hz:

28.875 in^3 sealed with 400Hz LR4 HP there's no way you can hit xmax with any sane power level... they're below 2.2mm xmax on 2kW (thermal rating is 400W), so let's see what they can take at 400W...

400W in 28.875 in^3 results in 220Hz LR4 HP for an F3 of 267.41Hz:
Blue Trace = maximum extension - limits power to 120W
Pink Trace = maximum power - takes 5x thermal capacity to reach xmax
Green Trace = optimized between thermal and extension
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I'm using MM2's IB on the door card of the F Type, 300-3,000 and they sound great. GB25's didn't fit, too deep. I thought MM3's wouldn't fit either but a Jag buddy got a Carbon Elate 93A set to mount just fine, he said the MM3's are amazing.
 

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No experience with the Morels but the best sounding system I put together was with the DLS Ultimate Iridium 6.3. Is that the same dome mid as your Gothia? Running active 24/db slope I ran those down to 400Hz for years. I still have them, I'll get them installed again eventually. They have an FS of 280Hz so the "doubling FS" rule of thumb doesn't quite apply. Perhaps I lucked out because I was only feeding them 40 watts from a DLS A8?
The DLS Iridium is a sealed back mid where the Gothia is open back and does sound better. I am running active , but i was running a lot more power. i have the iridium 6.3 but changed tweet to Up1i. Its the best sounding setup that i have done. There is so much detail and the vocals are amazing. I recently installed audison violino ii ,but will be going back to the DLS Up1i.
 
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