[MtBiker77]

I am looking for subs that will work well for home use in very small sealed cabinets with reasonable amounts of EQ. Ideally, I would find a shallow 10" driver that I can mount on either side of a speaker cabinet (bipolar) with a TM on top (3way active loudspeaker). Any subs outside of car audio with the cojones to get to 20Hz with or without EQ seem to be rather deep. Once you account for countersinking and venting out the pole, even a relatively shallow 5" mounting depth turns out to require a 13" wide cabinet.


Besides mounting depth, I'm struggling with small cabinets in general. For reference, a pair of Scanspeak 23W/4557 in 30 liters (total) sealed has an f3 around 35Hz which means minimal EQ. It's hard to find a low VAS, low Fs, highish Qts (SPL be damned) driver. Despite the fact that my present DIY speakers have lasted me 11 years, I still like the idea of buying parts that will still be available years later.


Ideas?

 

[brandonnash]

Despite your need for shallow driver depth the audiopulse line from parts express might work. Low fs on most of them, requires small enclosures, great sound quality too.

 

[tvrgeek]

oxymoron: good, small

Granted some are better than others, but current materials and engineering point the way to fairly large boxes and large cone total areas. I have never seen anything under about 2 cu ft that I can begin to call quality, and at that size, are limited in output and range. My view. Others may view differently. (Sunfire, Bose....). I don't see the big need to get carried away with giant subs as seem popular here. The few I have heard did not impress my. Maybe I heard the wrong ones. A couple of 60 to 80L in a room do fine for me.

 

[mjaudio]

I second that Audiopulse recommendation. I picked up a pair of 12" Axis when they were on sale for about 40% off which happens from time to time. I popped one into a 1.4 cu ft test box I had in the garage to try out and that little sucker pounds. They do need some power though and I was pushing it with a bridged QSC 2502.


For a small box the performance exceeded my expectations and I use 18" Mal-X's in my main system so I expect a lot.

 

[MtBiker77]

I was looking at this from the perspective of having a smallish driver in a small box, in which case the output would be limited and useless to anyone on this forum outside of a tiny room. This is the problem in that subs are designed under the assumption that you will only have one of them, so it's rare to come across the parameters necessary for a small(ish) driver to reach 20Hz. However, since I am going stereo and had originally thought bipolar (for force cancellation), I would quadruple my output instantly, and end up with something satisfactory in my existing room. I have an NHT1259 in a 2.1 system that has been adequate thus far, so all I need to do is match or exceed it's output. As a lesser consideration, since I would be moving from a 2 way + sub to a pair of 3 ways, the crossover point to the (sub)woofer would likely move somewhere north of 100Hz.


The Audiopulse LM10D2 in just 30 liters with "only" 500W is giving me an F3 of 31Hz sealed (meaning minimal EQ) and a max SPL of 107dB, which is dead on what I model for my NHT with its existing 150W amp (107dB, 27Hz Fs). Then +6dB for the second channel and I come out ahead. Even with the regular sticker price, it's still cheaper than a quad of the Scanspeaks. I know the selling point of LMS is linearizing BL over the entire range of excursion, but if you don't use 100% of your xmax, then is it detrimental?

 

[LTD02]



Quote:
Originally Posted by MtBiker77 /forum/post/16828532


I am looking for subs that will work well for home use in very small sealed cabinets with reasonable amounts of EQ. Ideally, I would find a shallow 10" driver that I can mount on either side of a speaker cabinet (bipolar) with a TM on top (3way active loudspeaker). Any subs outside of car audio with the cojones to get to 20Hz with or without EQ seem to be rather deep. Once you account for countersinking and venting out the pole, even a relatively shallow 5" mounting depth turns out to require a 13" wide cabinet.


Besides mounting depth, I'm struggling with small cabinets in general. For reference, a pair of Scanspeak 23W/4557 in 30 liters (total) sealed has an f3 around 35Hz which means minimal EQ. It's hard to find a low VAS, low Fs, highish Qts (SPL be damned) driver. Despite the fact that my present DIY speakers have lasted me 11 years, I still like the idea of buying parts that will still be available years later.


Ideas?

you lost me at "spl be damned".


just put a big lump of clay on any driver and you can lower its f3 down to whatever level you want.


if you really believe in "spl be damned".


in my humble estimation, that is goofy. i think efficiency is one of the most important aspects of speaker performance.


i'll be curious to see with what you end up.

 

[Looneybomber]

The old TC-sounds OEM-10 liked a Small box. Two, sealed would work great in 1.25-1.5ft no problem. There's also a pair on ebay right now, but the guy is asking 500/pr. I think they sold for 160/each back in the day. However, they are deep.


To reduce cabinet size in half, you can mount any driver isobarically, meaning if you wanted a pair of drivers, you'd instead need four. In the process, you'll lose 3db of output.

 

[MtBiker77]



Quote:
Originally Posted by LTD02 /forum/post/16829560


you lost me at "spl be damned".

My observation and assumption is that


low f3 + small box = low VAS + low Fs + highish Qts = low efficiency


which is a trade-off I am willing to make only because I am crossing over actively.

Quote:
Originally Posted by LTD02 /forum/post/16829560


just put a big lump of clay on any driver and you can lower its f3 down to whatever level you want.

I would prefer not to re-manufacture any driver parameters.

Quote:
Originally Posted by LTD02 /forum/post/16829560


i think efficiency is one of the most important aspects of speaker performance.

I disagree about the ranking of driver efficiency, and I'm not sure I would want to put a Lambda driver in a small sealed enclosure and find out what happens to the cone (and otherwise low distortion motor) when I apply obscene amounts of EQ to force the alignment I want. It just sounds like a bad idea and not one I would consider without the insistence of people who have successfully done such things.


So, LTD02, given my current constraints (and I will clarify if asked), what would you recommend?

 

[brandonnash]

It sounds like the level of knowledge you have you are big into quality sound. You can get what you want done, but try to remember that old saying "extension, spl, and small enclosure. Pick two." you can keep some of that with eq, but you run into distortions sometimes in the obscene level when trying to push a driver with extra eq. You also have to think about what 10-12 db of boost would require from an amp and also there is the possibility of running past your driver's thermal limits while eq'ing it that much.


I probably missed it, but why are you wanting such a small enclosure? Do you not have the room for say a 5 cubic foot enclosure?

 

[MtBiker77]



Quote:
Originally Posted by brandonnash /forum/post/16830052


I probably missed it, but why are you wanting such a small enclosure? Do you not have the room for say a 5 cubic foot enclosure?

Honestly, I don't understand when people have multiple 15" or 18" subs with 20+ mm of xmax in massive enclosures unless they have gigantic rooms and watch action movies when their wives are out of the house--both of which I can appreciate and we should probably become friends. I would like to have huge cabinets, large diameter drivers, and use a tiny fraction of my xmax, but I'm also married, and I live in a townhouse. Plus, my subs in this case are going to be the bottom end of some 3way speakers, so the footprint is going to have to be small, and depending on the final design, the volume will be some iteration of comparatively tiny. If this venture is very successful, it would be nice to ditch a HT sub entirely and let my processor mix the sub channel back into the mains...


To address the adage, I would trade sensitivity and max SPL for extension and a small enclosure. Sensitivity can be overcome with Wattage, and max SPL only needs to meet/exceed what I have now. I agree that 10-12dB of boost is excessive and I don't want to consider it unless someone tells me "I did it in such and such scenario and it works great." So, if I can get an uncorrected f3 anywhere near 30Hz then I may only need 3-4dB of boost at 20Hz if I force a corrected alignment closer to Qtc 0.5 and -6dB at 20Hz.

 

[Jay1]

How about the HI-VI SP10 . It will give you an F3 of 43hz in a box as small as 17L (.6 ft3)

 

[djarchow]

Not sure if they meet your requirements for shallow, but the 12" Rythmik Audio Servo subs have an f3 of 14 Hz in an 18" cube. They will not play super loud, but they do sound very good.


Reards,


Dennis

 

[LHD21]



Quote:
Originally Posted by MtBiker77 /forum/post/16830531


Honestly, I don't understand when people have multiple 15" or 18" subs with 20+ mm of xmax in massive enclosures unless they have gigantic rooms and watch action movies when their wives are out of the house--both of which I can appreciate and we should probably become friends. I would like to have huge cabinets, large diameter drivers, and use a tiny fraction of my xmax, but I'm also married, and I live in a townhouse.

I dont know of anyone here who isnt using a good majority of their drivers excursion except maybe bossabass or MKtheater. I know both of my 18" builds put me at a couple of mm from xmax under nearly max load. Bossabass said his subs are amp limited and I've never modeled one to see how the excursion plots.

 

[vasyachkin]



Quote:
Originally Posted by MtBiker77 /forum/post/16828532


a pair of Scanspeak 23W/4557 in 30 liters (total) sealed has an f3 around 35Hz which means minimal EQ. It's hard to find a low VAS, low Fs, highish Qts (SPL be damned) driver.

...

Quote:
Originally Posted by MtBiker77 /forum/post/16828532


Ideas?

yes i have an idea for you. forget about small sub with no EQ. that's the stupidest thing you can do.


either you do a big sub or you use a lot of EQ.


and scan speak is not a subwoofer. its a tweeter tuned for bass. scan speak doesn't make woofers let alone subwoofers. they make excellent tweeters though.

 

[brandonnash]



Quote:
Originally Posted by vasyachkin /forum/post/16835341









and scan speak is not a subwoofer. its a tweeter tuned for bass.

Disagreements aside, that is funny. Made me chuckle.

 

[penngray]



Quote:
Originally Posted by MtBiker77 /forum/post/16830531


Honestly, I don't understand when people have multiple 15" or 18" subs with 20+ mm of xmax in massive enclosures unless they have gigantic rooms and watch action movies when their wives are out of the house--both of which I can appreciate and we should probably become friends. I would like to have huge cabinets, large diameter drivers, and use a tiny fraction of my xmax, but I'm also married, and I live in a townhouse. Plus, my subs in this case are going to be the bottom end of some 3way speakers, so the footprint is going to have to be small, and depending on the final design, the volume will be some iteration of comparatively tiny. If this venture is very successful, it would be nice to ditch a HT sub entirely and let my processor mix the sub channel back into the mains...


To address the adage, I would trade sensitivity and max SPL for extension and a small enclosure. Sensitivity can be overcome with Wattage, and max SPL only needs to meet/exceed what I have now. I agree that 10-12dB of boost is excessive and I don't want to consider it unless someone tells me "I did it in such and such scenario and it works great." So, if I can get an uncorrected f3 anywhere near 30Hz then I may only need 3-4dB of boost at 20Hz if I force a corrected alignment closer to Qtc 0.5 and -6dB at 20Hz.

IB designs have zero boxes in the room...100% WAF.


Custom HT room has speakers subs behind false walls or built right into the walls, therefore the 11 cuft boxes are hidden.


Have have both but I also have fairly large house and a monster family room. I have been married 14 years, my custom HT room is what my wife calls the MAN ROOM

There are many ways to build and hide great sub systems. You have compromises so you need to prioritize them to get a solution.


Last thing, sensitivity does not mean poor SQ.

 

[rlhowell]

Maybe you could try another approach and hide the sub in a piece of furniture, as I am doing. I am going with a chest. I already have an end table and want more.


I find chest are low and blend in well with 3" feet and sub and amp on the bottom. Build a cheap plywood mockup of 2 cf , paint it black and see what it does to your married life. SWMBO will put plants, or her pocketbook on it and smile. I have a set of plans for a nice chest I have been considering for years and measured it the other day and found it had 8 cf gross, 36x25x20 on 5" legs.


Just a thought. Good luck


Bob

 

[mjaudio]

This thread had me thinking about the Audiopulse Axis 12's I have again so I popped 1 back in the 1.4 cu ft test box I have to listen to it.


My room is big so for now I am using the Mal-X and 4 10" NHT drivers until I can build some more. I first tried out the Mal-X by-itself before the Audiopulse so I could do a mini comparison, I know it's not a fair comparison.


Both were driven by a bridged QSC PLX-2502 and eq'ed with a SMS-1. The AP Axis was placed right on top of the Mal-X.

You would think the Mal-X would destroy the 12" Axis and for shear SPL and low end it is noticeably better but the Axis is like a pissed off Chihuahua going after the Mal-X. I actually had to get up and look at how the excursion on the Axis was just going crazy while playing the "Seek and Destroy" chapter from LF or DH Blu-ray. It wasn't playing effortlessly like the Mal-X but it was throwing some serious punches.


My room is hard to energize since it is big and open so I am still shocked at how well the AP Axis 12" does in here by-itself. I also have a TC-3000 15" which is the 12" big brother but it needs so much power that the 12" is easier to drive in my room without distorting.


I should really find some time to build proper enclosures for both and flex the walls with the 12" Axis and 18" Mal-X

 

[MtBiker77]

I have pretty much abandoned the idea of using bipolar subs, with multiple smaller diameter drivers per channel. There just aren't (m)any good options. High quality subs and woofers just don't have much overlap, and certainly not in small drivers meant for small boxes from manufacturers who are cash flow positive. I wanted bipoles just for vibration cancellation, but if I can decouple the mid and woofer cabinets in some way, or separate them entirely, then that would open up a couple of new options. I have a ton of renderings of ideas already, but I'll probably just start a build thread when I figure out what I'm doing.

 

[Montekay]



Quote:
Originally Posted by MtBiker77 /forum/post/16874063


I have pretty much abandoned the idea of using bipolar subs, with multiple smaller diameter drivers per channel. There just aren't (m)any good options. High quality subs and woofers just don't have much overlap, and certainly not in small drivers meant for small boxes from manufacturers who are cash flow positive. I wanted bipoles just for vibration cancellation, but if I can decouple the mid and woofer cabinets in some way, or separate them entirely, then that would open up a couple of new options. I have a ton of renderings of ideas already, but I'll probably just start a build thread when I figure out what I'm doing.

The 6.5" Tang Band from PE pn# 264-832 will require EQ but that's ok because you can use a lot of them in a relatively small box which gives you a lot of voice coils to share the load. They have high excursion capability, low noise, and low distortion. You could for example use two in front and two in back of the baffle and keep a narrow footprint while still having significant output capability. These are what I would use if I wanted to make a compact sealed sub. The more of them you use the less power required and the more coils to share the load. If you can allow the height to get three in front and three in the rear and then have two of these in the room you should have plenty of output and never worry about power issues.


edit: Oh btw, they also make an 8" version of this same driver but it's really noise and pretty much useless in my opinion. It's too bad TB doesn't investigate this and figure out why the 6.5 is so good and the 8 so bad. If the 8 could be made as good as the 6.5 it would also be a great option.


mk