DIY similar to a Velo SPL1500/DD15, Revel B15 or Fathom F113 (sealed)???

[BoomieMCT]

mayhem13 wrote:

How about 2 Mach5 MJ18's in 100liters-one forward one rearward-20" cube cabinet-laminated 20x20x3/4 mdf each with a 17" hole cut. This would have zero resonance and if you installed 2 side firing PR's-oh my all this from a 20" cube and less than $500 for drivers and PR's

You'd need some serious PR's to handle two 18" drivers.

[mayhem13]

2 AE 18's weighted to 1600g at 4.2hz-Qmp 67.89 each 1200cm6^2. Check em out boomie-oh xmax is 3" on the PR's

[BoomieMCT]

mayhem13 wrote:

2 AE 18's weighted to 1600g at 4.2hz-Qmp 67.89 each 1200cm6^2. Check em out boomie-oh xmax is 3" on the PR's

That's 3" point to point - most people would say that's an xmax of about 38mm. I'd have to run the numbers (at home) to see how that matches up.

Could be fun .

[BoomieMCT]

mayhem13 wrote:

2 AE 18's weighted to 1600g at 4.2hz-Qmp 67.89 each 1200cm6^2. Check em out boomie-oh xmax is 3" on the PR's

That's 3" point to point - most people would say that's an xmax of about 38mm. I'd have to run the numbers (at home) to see how that matches up.

Could be fun . Of course at that point you are spending more money on the passive drivers then your actives . . .

[mayhem13]

yeah that's true but the OP seems quire adamant about small footprint. Just as JL gets there with $$$, so will he. BUT if he increased box size to 30" cube, then he could create quite a rumble. He COULD do one of these EV pro designs with 4 drivers and still be under $500 but his amp is too small.

[rodH]

so are you guys saying that the (2) TC/Torrent drivers aren't going to be enough??

[BoomieMCT]

rodH wrote:

so are you guys saying that the (2) TC/Torrent drivers aren't going to be enough??

Depends on personal tastes and how much of a bass-head you are. I have two sealed 12" Titanics in my HT and it is *just right*. My HT is half the volume yours is. It is possible that two Minstrals will work for you but without knowing your tastes and your room who can say?

[BoomieMCT]

BTW for the graphs I made here are the Qtc's assuming "heavy fill";

2x12" Titanic: 0.601
1x15" Titanic: 0.595
2xShiva-X: 0.727
1xTempest-X: 0.846
1xIXL18: 0.604
2xMinstral: 0.607

[rodH]

BoomieMCT wrote:

BTW for the graphs I made here are the Qtc's assuming "heavy fill";

2x12" Titanic: 0.601
1x15" Titanic: 0.595
2xShiva-X: 0.727
1xTempest-X: 0.846
1xIXL18: 0.604
2xMinstral: 0.607

sorry for my ignorance, what does Qtc relate to? and how much is "heavy fill"?? Does this make the box relatively larger or smaller?

[mgboy]

BoomieMCT wrote:

BTW for the graphs I made here are the Qtc's assuming "heavy fill";

2x12" Titanic: 0.601
1x15" Titanic: 0.595
2xShiva-X: 0.727
1xTempest-X: 0.846
1xIXL18: 0.604
2xMinstral: 0.607

I'd get two of the Shiva's and pump the watts through them, or take a more efficient route and go with the IXL18. I'd take both those options over the others, but that's the my opinion. The Titanic's are good, but over priced, you don't gain anything from going with one tempest over the Shiva's or IXL18, and to mistrals are at the back of the pack.

[a1161979]

rodH wrote:

sorry for my ignorance, what does Qtc relate to? and how much is "heavy fill"?? Does this make the box relatively larger or smaller?

The Q is really the roll of the dox displays, a Q of around .8 will have more response from 35 to 80hz at the loss of low frequency sensitivity, hence some people like to run a Q of .7/.8 for music or lower for Home theater use Im currently planning on building some subs with a Q of .7 for HT use so it will be interesting to see how they perform Id probably aim for a Q of around .6 for home theater or you can do what some recomend (which i am) and build to a Q of .7 then slowly add stuffing to the box which effectivily lowers the Q

Heavy fill is polyfill stuffed into the box almost completly, this make the box appear larger than it really is, for example say a 100L box with a Q 0f .7 or a 150L box with a Q of .6, although not really true providing heavy fill the 100L box could be made to have a smilar response as the 150L box assuming that has no stuffing

[BoomieMCT]

rodH wrote:

sorry for my ignorance, what does Qtc relate to? and how much is "heavy fill"?? Does this make the box relatively larger or smaller?

It's the total system Q.

[rodH]

OK guys. Here is the deal, I have hinted about it in the past, and I know it isn't popular, but the LOOK of the driver actually is something that is very important in this set up. I want something that looks like a more modern driver like the TC, torrent or Rhythmik type of look. I am going to run it without a grill and my would be much more pleased if it had the more modern look of these drivers as it would match the decor in out house a LOT BETTER. She has let me put so many seperate pieces in this system and speakers that I need to value her opinion, the driver will not use a grill and will be visable. I know it may cost a bit more, but is there anything else out there that looks good and performs well?

Are the Torrent drivers so bad that that is the reason no one is considering them?

[mgboy]

rodH wrote:

OK guys. Here is the deal, I have hinted about it in the past, and I know it isn't popular, but the LOOK of the driver actually is something that is very important in this set up. I want something that looks like a more modern driver like the TC, torrent or Rhythmik type of look. I am going to run it without a grill and my would be much more pleased if it had the more modern look of these drivers as it would match the decor in out house a LOT BETTER. She has let me put so many seperate pieces in this system and speakers that I need to value her opinion, the driver will not use a grill and will be visable. I know it may cost a bit more, but is there anything else out there that looks good and performs well?

Are the Torrent drivers so bad that that is the reason no one is considering them?

While I understand that point, many will agree here that looks don't play a big role in how a speaker sounds. =P

That aside, it's not that the Mistral (db500) is bad, just that it won't fill your needs. If you were to get 3 or maybe even 4 of them (they're cheap) then you'd be getting into the "HT Arena."

[mayhem13]

The Dayton RS series have really good looking aluminum cones and are well known for their very low distortion. They make a 15" high output model that uses a very small box. This driver with 2 side firing 15" PRs(also very good looking from acoustic elegance @ $50 each) would make for a nice clean sub and a real performer-2 of these would easily fill your room for around $500.

[rodH]

OK,

Lets take a closer looks at the graphs that were posted here earlier (again, thanks for doing them).

Lets compare and someone tell me if I am looking at them wrong. FIRST, lets get a few things out of the way. I am NOT a HUGE bass head, I prefer "Music" over HT and pure SPL output. The sub is corner loaded and a velodyne SC1250 amplifier (1250w into 8 ohms RMS, and 3000w into 8 ohms peak......at 4 ohms, of course it is more). This sc1250 also has parametric EQ abilities, so I will be flatening out the FR curve using it for room and driver. Also the sub will ONLY be used to freq below 80 hz

so if you compare the graphs, also consider that there is actually 1250w RMS, and 3000w peak (if we are talking 8ohms). Also consider I will be using a PEQ, corner loading, and if heavy fill helps, I will do that too.

So here are the graphs before any of that is considered:

Torrent/TC 12" (x2)=106 dB @ 20 Hz, 118 dB @ 60-70 Hz (12 dB rolloff?)

Dayton Titantic 12" (x2)=106 dB @ 20 Hz, 118 dB @ 60-100 Hz (12 dB rolloff?)

Titantic 15" (X1)=106.5 dB @ 20 Hz, 118.5 dB @ 60-100 Hz (12 dB rolloff?)

Shiva X (x2)=106.5 dB @ 20 Hz, 118 dB @ 60-100 Hz (11.5 dB rolloff?)

Tempest X (x1)=106.5 dB @ 20 Hz, 118 dB @ 50-100 Hz (11.5 dB rolloff?)

IXL 18" (x1)=107.5 dB @ 20 Hz, 117 dB @ 60-100 Hz (9.5-10 dB rolloff?)


I guess I am supposed to look at

1. how flat the curve is

2. How many dB at 20 Hz

3. How many dB at peak

4. Where the Peak is

5. Where the low is

6. How fast it rolls off

If this is true, the graphs don't look that much different to me.

Pure output at 20 Hz, the 18" IXL looks the best, by 1.5 dB (is this really that big of a deal?).....The IXL also looks the flatest with the least roll off, but only by a couple dB, is this really a big deal as well?). It seems like they are all pretty close and I would notice subtle difference in my PEQ, room placement, acoustics and power than I am going to notice at the actual driver.

Please tell me if I am looking at these numbers wrong.

Thanks.

[rodH]

are these any decent on fleabay?



BNIB Pair of Eclipse, TC Sounds TC2+ 12" Subwoofers NR!
Same as Tc-1000, AudioPulse Epic, Aluminum Eclipse Cone Item number: 320235017731

[rodH]

another interesting prospect is the Infinity Perfect 12" VQ. Looks like some people have used them with some success, any opinions of these drivers, there seems to be lot of them on ebay.

[BoomieMCT]

rodH wrote:

Pure output at 20 Hz, the 18" IXL looks the best, by 1.5 dB (is this really that big of a deal?).....The IXL also looks the flatest with the least roll off, but only by a couple dB, is this really a big deal as well?).

The IXL18 only looks the flattest because they didn't publish the Le of their driver. The voice coil inductance of the motor will act like a lowpass. The bigger the Le, the lower this effect will happen. I think I put a note about that below the graph.

[rodH]

anyone have any opinions on the soundsplinter 15"??

http://www.soundsplinter.com/rlp15_s...formation.html

[mayhem13]

The rlp15 is a monster of a sub and will best a F113 in a properly designed PR design with a slightly larger footprint( allowing for the PRs of course). If you can afford one, go for it.