Combo! Sealed Sub below Mains

**ironglen** · **10-09-09, 03:29 AM**

So, this is my thread over in diy speakers. I need help with the sub portion as I know very little about sealed subs. The ED driver is recommended for 1.0-1.2 sealed or 1.5-1.8 ported, so I'm thinking I could use a sealed 0.9 ft^3 net; plus I don't have/want another hpf to set separately from the hpf on my LLT Mal-X. The concerns on my last post 10/09 are in addition to the fact that the driver depth is a deep 5.75", so with .75" mdf, the driver would be 5" deep and the cab width would have 6" depth, is this problematic for sealed? I intend to have another .75" mdf trim along the bottom edge side of the tower, but it was primarily prevent side-tipping of the tower, however I could extend the trim to the same height as the opposite side sub baffle (~14"), if it would help.

The depth of the sub and possible need to eq it to balance the tritrix above it are my primary concerns. I'd really like to integrate these...

**Moonfly** · **10-09-09, 11:23 AM**

It sounds to me like your trying to build something like these speakers here. Its obviously something that works so there should be no concern that way.

It looks as though an external crossover might be the way forward, and you could use separate speaker terminals on the cabinet purely for the sub. I dont think there will be any problems with what your envisioning going of the speaker in my link, and I think using them for a little inspiration may prove worthwhile. If your serious about the bass driver being for sub bass though, fit the driver on the side and find a good 10" one like the XTZ, then simply produce only sub bass with this. Sub bass is omnidirectional, so the side mounting then is no longer an issue.

IMO, anything less than a 10" driver is simply a mid-bass driver and not a true sub.

**ironglen** · **10-09-09, 03:20 PM**

Thanks for the encouragement- I was planning on side-mounting as the front is only 7" wide while the sides are 14.25" deep. My biggest concern is needing to eq the 12" to boost the low end as it looks pretty anemic without something in the way of 5db boost @30hz, with low Q (~1) so it affects a wider range down low. I guess an eq for these mains would be highly desirable/needed. I'm also not sure about that shallow depth...Any others' help appreciated.

**Mike P.** · **10-09-09, 07:00 PM**

Quote:

The ED driver is recommended for 1.0-1.2 sealed or 1.5-1.8 ported, so I'm thinking I could use a sealed 0.9 ft^3 net;

Which ED sub and what was the Q when you modeled it in .9 cu. ft.?

**ironglen** · **10-09-09, 08:03 PM**

Hi Mike, uh, I don't remember, I think .707. It is the ED E3.12 driver, and the ED specs recommend a 1.0-1.2 ft^3 sealed or 1.5-1.8 ported, so I figured sealed make more sense as the volume is tight, with the enclosure being narrow.
My 'mains' (in-ceiling 6.5"s) do ok for ht, but music kinda sucks as I have to use surround to even obtain respectable volumes (and I don't really like the sound very often). I got the idea to build my own from the tritrix, and most diy'ers highly recommend going with a proven design, though I would really like to use the modeling software for speakers and make my own. I have to admit what they say makes sense, however, I figured the lower cost designs would be weak on overall spl, especially lows, so I'm looking at integrating a bass driver that side-fires below the mains. I had the plans drawn up for two 'ingenious' sonosubs (unique baseplate mounting

), but since I don't know how to integrate subs together, I figure my sound would benefit most from improved mains, so I'm considering this. I could even pick up a couple inexpensive 10"s and use them instead. I figured since the tritrix was short, it would be a two-bird, one-stone kind of deal. Or should I just slightly extend the height leaving an empty speaker base and mount my xovers there? I just don't to build these and wish I'd gone bigger/more powerful. What do you think?

**Mike P.** · **10-10-09, 12:30 AM**

E.D. recommendations for box size is for car audio. Box size for your application will depend on what yo are trying to accomplish. How low do you want them to go and how high will they be crossed over to the mains?

Be aware that building crossovers is part science and part art. It usually takes tweaking to get a design to sound right. There are crossover design programs available that will state what components and values you will need to get you in the ball park. Doing it right means measuring the response and making any nessecary changes to make it smooth. You have to be willing to put in the time and effort.

**ironglen** · **10-10-09, 12:55 AM**

Thanks for the very important point- I'm sure the car guys emphasize spl over freq response. I figured I'd use a standard 80hz crossover since my preamp can do either digital or analog 80hz subout. I imagine I'd want to be able to play with authority to 30hz, since I'll definitely be sending sub 60-70hz material to my Mal-x during ht use. What I'd like to do is be able to play this pair in stereo for music only, perhaps without firing up the Mal-X and associated amp, that is, if this pair can really shine, otherwise that point is moot.

What do you think about all of this? The other concern I have is whether the gain adjustment on the amp will suffice for blending the high/mid and sub/woofer. Do you think I should just scrap this idea and build my sonosubs for now? After all, I don't have a huge house to just be placing boxes and tubes everywhere!

I have a couple amps that I could use which pretty much determine which one I would use with either ported or sealed: an svs 500w mono with built-in hpf @ 12,16,20, or 24hz that I could series wire the pair for 500w@4ohms, OR a samson 285w x2@4ohms each, no hpf (actually planned to use this for the mains somehow). So, I have options. Obviously, I want to optimize the bass output if using these ED drivers and have a set of real mains that look good and sound even better.

**Mike P.** · **10-10-09, 02:57 AM**

The SVS amp won't be an option for a pair of these subs. The coils are D2, you can wire them together for 2 ohms or 8 ohms, but not 4 ohms.

This is with 285 watts, no HPF is required since Xmax isn't reached until 5 hz. It wouldn't take much to build a pair of tubes and see how they sound with the speakers you have now, maybe it's enough.

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**ironglen** · **10-10-09, 03:29 AM**

My mistake. svs amp is out (now I remember why I originally picked up the samson 550: sonosubs build)

Which speaker are you referring to Mike? The overhead in-ceiling L-R are the ones I really want to 'replace', particularly for 2 channel audio, but I'm wanting to make sure they can handle the full range, thus the attempt to incorporate the ED 12"ers into the design.

I've been playing with winisd, but the sealed roll-off is so much more dramatic than the ported models I've been playing with, so I'm kind of in left field. Is eq'ing always needed to flatten the response or do most people's rooms provide the gain?

The tritrix in a smaller sealed/ported configuration should output ~104db, so should my complimentary woofer output similar spl? The ED may output too much for the tritrix uppers, I'm afraid. Do you think I should look at smaller, less powerful 6.5" to 10" drivers for this task?

**Mike P.** · **10-10-09, 03:42 AM**

You already have the ED subs, there's nothing saying you have to overpower the tritrix uppers, turn down the ED's to balance it out.

**ironglen** · **10-10-09, 03:52 AM**

Quite true. Another member pointed out this design which I think looks quite nice and would try to emulate. Do you think the short depth would be a problem with the driver, being sealed? I'm sure that quality construction and some bracing on the longer panels will be of benefit, but...?

Do you think this is a good use of the drivers? I tried to think up a way to use bookshelf-type mid/highs with a sonosub design I worked up, but it was going to place the mid/highs too elevated adn would require so much modeling/trial and error it was frightening

**Mike P.** · **10-10-09, 08:05 AM**

As long as there's a couple of inches of room behind the sub for the pole vent they should be ok. It might be better to ask ED support to make sure of the mimimun clearance required.

**evilskillit** · **10-10-09, 02:28 PM**

How much space could you get in the bottom if you build the Tritrix bookshelf enclosure on top instead of the transmission line? I would imagine if you did that you could get more like 1.5-3 cu ft in the bottom. Especially if you're willing to make the sub portion of the cabinet slightly wider or deeper than the upper speaker part? Basically you'd have bookshelf speakers with subwoofers as speaker stands, except you can build them all into one enclosure instead of 2 separates. This is often referred to as the Bookshelf / Bassbin configuration.

**SQCherokee** · **10-10-09, 02:52 PM**

I have found that modeling software can give you a good idea on enclosure size to build, however most manufactuers can give you the best idea for what size to use. The range of 1.0-1.2 sealed can actualy make a huge difference in SQ. May sound great at 1.2 then just get loud and boomy at 1.2.

ED can probably give you the best recomendation.

**Moonfly** · **10-10-09, 05:03 PM**

Quote:

evilskillit wrote:

How much space could you get in the bottom if you build the Tritrix bookshelf enclosure on top instead of the transmission line? I would imagine if you did that you could get more like 1.5-3 cu ft in the bottom. Especially if you're willing to make the sub portion of the cabinet slightly wider or deeper than the upper speaker part? Basically you'd have bookshelf speakers with subwoofers as speaker stands, except you can build them all into one enclosure instead of 2 separates. This is often referred to as the Bookshelf / Bassbin configuration.

Referring back to the link I originally posted back in post #2, the same company also do the same thing. You can see the example here, using these and these, and IMO would probably be the best way for the OP the achieve his goals.

I also think they look very slick, as long as you have the room required. My original link would of course be the size compromise option, so take your pick really. Also keep in mind your system would basically have 2 subs, so even 10" drivers will perform above expectations as you'll have two, including the desirable +6db and non locatable bass benefits.

**evilskillit** · **10-10-09, 05:37 PM**

Using my amazing paintbrush skills I have drawn a crude picture that represents what I'm talking about with the bookshelf enclosure inside of a large sub enclosure.

**Moonfly** · **10-10-09, 06:08 PM**

Using my amazing copy and pasting skills, here is a picture of this kind of thing in reality

:

I must confess the DIY build will hold a large amount of interest for me and I'll follow it closely

. Regarding the port, I would choose which way it fires to suit your room best, and perhaps place it at the bottom of the box, but thats just my personal preference. The idea evil puts forward will certainly maximise cabinet size with minimum impact on the overall cabinet.

**ironglen** · **10-10-09, 06:53 PM**

Ok, you guys are showing me some nice stuff and stimulating ideas. As much as I like that xtz speaker, I'm revisiting the idea of using my sonotube to now be used to build the upper and lower chambers-which I previously thought would look ridiculous and be top-heavy with a box mounted over a cylinder. But now, I'm seriously considering a smaller mid/high sealed cylinder mounted over a larger sub ported cylinder. Do any of you guys know/think placing the tritrix drivers on the front of a cylinder would have adverse effects? Of course, there would be a narrow (7-8")flat baffle to which the drivers would be mounted, but a curved side would be, 'around the corner', so to speak. Reason I ask is I have sonotube that is 14.5" diameter by 50" tall that I am now considering creating two cylinders, a smaller sealed one with the tritrix drivers mounted above the top of the other cylinder. The lower one would hold a downfiring 12", with the top cylinder a few inches above the ported topcap, kind of in place of a top plate. It would meet waf as it would match my large sono, however, I'm not sure how carpeting the top cylinder would affect sound, if any. The 7"-8" wide driver baffle would be painted mdf/plywood and the driver holes are rather small through the cylinder, so I think this will work.e painted mdf/plywood and the driver holes are rather small through the cylinder, so I think this will work.

**Moonfly** · **10-10-09, 07:09 PM**

Sounds perfectly workable, although I cant think of any examples of that exact design off the top of my head. I cant think of any downside to what your thinking, other than perhaps how the port of the sub might affect the main speaker. Thats one for the more advanced to answer though.

It'll sure look funky though, and be a unique design you can call your own and show off

**evilskillit** · **10-11-09, 12:43 AM**

Yeah. I was using my "amazing paintbrush skills" to get my point across about being able to nest the smaller speaker cabinet inside of a larger one, making 2 speakers look like one big cabinet and increasing the depth behind the upper to make a large cavity for the subwoofer to be in.

As far as the round tube to put the Tritrix in, I assume you're talking about something like this? Except maybe flat on the front?

The front baffle width is important, if you change that it will affect how the speakers sound. However, if the internal volume is about right, and the front baffle width is right then theoretically it will be better than a box, since round enclosures have less standing waves. Tho in reality there doesn't seem to be any measurable difference.

If you search for curved diy speaker or curved back enclosure you can find tons of designs where people make speakers with round backs using various methods, usually stacked laminte plywood cut on a CNC machine, which looks great but is expensive and labor intense.

Here is another design that someone took that was based on a square box and made it into a rounded enclosure.
http://www.audiojunkies.com/blog/863...d-diy-speakers

**ironglen** · **10-11-09, 02:24 AM**

You and I are thinking alike

I liked your enclosure inside an enclosure idea.

That speaker is you show is similar to what I'm thinking, only upright with down-firing sub with upward facing sub-port. The upper 'mini'-cylinder would house the MTM or TM on a flat baffle, as in your example.

Now, I'm looking at whether I should use the tritrix, or a different proven design. I am finding that the long-ish baffle of the tritrix MTM design uses about twice the frontal area for the required volume (~.7ft^3 or 20L) because the resultant cylinder after accounting for drivers, port, baffle, is likely around 1.0ft^3 (30L), or double the optimal volume for the ported design.

Any ideas on another low-cost, yet competent proven design/kit? Perhaps using a dual 4" driver MTM, or 5.25" or 6.5" TM configuration? It only has to be flat to 80hz, but should handle 100wrms @8ohms, or even greater @4ohms input.

**evilskillit** · **10-11-09, 02:47 AM**

There are a ton of great designs out there. There aren't a ton that fit your criteria but there are quite a few.

The Zaph ZA5.2 would work.
http://www.madisound.com/catalog/pro...oducts_id=8648

Roman's Microbe would work if you ported it, sealed it barely hits 80hz. I'm using microbes that were redesigned to use a vifa XT25 tweeter and they sound incredible.
http://www.rjbaudio.com/Microbe%20SE/microbe%20SE.html

The Modula MT is a great design, but substantially more expensive than some of the others in your group.
http://htguide.com/forum/showthread.php4?t=13154

The RS150MTM or Lineup MTM would work.
http://www.htguide.com/forum/showthread.php4?t=28655

And there is The Girl From Ipanema
http://undefinition.googlepages.com/...irlfromipanema

These are all going to have superior highs and mids compared to the Tritrix kit, and are smaller. However as for sheer output volume and price, none of them are going to touch the Tritrix in that respect, 2x 5.5 woofers are just going to be able to push more air than 1 5 or 6 inch woofer, and all these designs are over $120. But they're smaller and sound better.

Edit* GR Research AV1C would also be a candidate. I don't know about their tweeters but the woofer used in this unit is supposed to be a great driver.
http://www.gr-research.com/index.asp...ROD&ProdID=135

**ironglen** · **10-11-09, 03:16 AM**

You're helping me a whole lot-I found the zaph, but not the others- the power handling may not be there on some of these, but should be fine for ht use crossed at 80hz, then, if I power it up for 2ch, I can move it from 80hz up to 100-150hz as the subs will be in stereo emanating from each speaker. If I can get into one of these for under $200 and have a marked sound improvement, I'll be golden. I'll look these over...

**ironglen** · **10-12-09, 02:07 PM**

I've been modeling mids in sealed enclosures along with the ED 12" driver, and the dayton 5.25" haven't handled the rated 30wrms as stated-more like 35wrms input as a pair. Doesn't winisd use rms for input power calculations?

A pair of peerless 5.25's with 5mm xmax modeled with 110w input vs the dayton's 2.5mm modeled with 30w input-and the spl output of the peerless' was much more in-line with the spl output of the ED 12" with 175wrms input. Obviously this is a big difference, and consequently has me worried about using the dayton's...

Since my preamp will handle the 12" to 5.25 xover duties, I'm thinking about these bargain peerless' mids again, possibly with the same dayton tweeter and maybe trying to learn the xover modeling software.

**evilskillit** · **10-12-09, 04:02 PM**

That is possible, and if you pull it off, more power to you

Another thing you could look into is putting the Tritrix in a small box that is ported with a port tuning around 80hz to take advantage of the lowpass filter. Try playing with the porting of the dayton drivers, move it around 50-80hz and see how it affects the power handling. Put on a LPF and see what that does for you.

The excursion down to 80hz should be substantially reduced, increasing power handling, and excursion below 80hz wouldn't be much of an issue due to the sub/mid crossover.

Just dinking around with Winisd I put them in a 9 litre box tuned to 76hz and you can apply 30 watts without exceeding excursion till below 70hz, and peak output is over 105db.

You could use a 3" round 8" long port. Tho the first port resonance shows up at 850hz, don't know if that would be a problem or not... Anyways you see where I'm going with this.

Something to consider. If you really want to get into designing your own speakers you should. It seems awesome, I'd like to try it some day. However if you're trying to build something better than the Tritrix for not much more, by the time you buy a microphone, get some books, other measurement hardware, buy drivers, build prototype baffles, build prototype crossovers, possibly scrap those, buy more and do it again you'll have spent several hundred dollars plus your time. At that point you could have just built a pair of Natalie Ps, or Mini-Statements, or Dayton RS TMWW or Kahnspires. All large loud, powerful full range floor standing speakers that can be built for less than $600 on average, which is probably what you'd end up with sunk into designing your first set of 2 way speakers.

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