Subwoofers upgrade on the brain

[---k---]

Hi All,
It has been a loong time. When I moved 6-years ago, I gave away my big ported subwoofer box and swore off ever carrying one of those down into a basement again. The plan was to finish out a basement with projector, wall, and IB. But, life got in the way and never got around to it. Most of my gear sat boxed up in basement. But, I recently got the Khans setup and paired it with a new 77" OLED and some nice recliners. The family is really enjoying it.

For subs, I'm using a pair of circa 2004 SoundSplinter RL-p15 D2 subs in sealed ~93L boxes. One on each side of the tv. I set them up / EQ using only Audyssey x32 on my old Onkyo receiver. I haven't run any tests or measurements, besides watching a bunch of Disney and Pixar movies. But, to my ears, they sound pretty good in my concrete basement. I'm confident that I'm getting pretty good gain down low.

But, upgrade-itist has gotten ahold of me. I think I just want someone new, because new has to be better, right??? Then, I saw that PE is selling the Ultimax 18 paired with a 4cuft box. It's basically the same size as I have now, which appeals to me. I'm getting old, lazy, and time limited. So the fast build of a pre-built has a lot of appeal. Looked perfect.

But, when I model it, I scratching my head thinking I must be doing something wrong. This is powered by my old Behringer EP-2500, which has 650W per channel (so each sub would get its own channel).


I expected a more gain going from a 15" to and 18"... it is about 2db between 20hz and 30hz. And this graph shows my current 15" out performing the Ultimax 18" from 50hz up.

So, it has me wondering if this would be an upgrade at all. But, I also wonder about tech and quality. Has things changed in the last 15 years that would make a current Ultimax better than a 15-year-old Sound Splinter RL-15? Looking around on the internet, there are various opinions of both the Ultimax. I've seen lots of rave reviews, but other say it isn't musical, lacks punch, it is poor for mid-bass being defined as above 50hz.

My Soundsplinters were designed with XBL way back when.

And then there are the crazies that recommend cheaper drivers in big ported or horns and swear they'll have less distortion, because they aren't driven hard. I don't know what to make of that. I have a hard time believing it. I'd like to be able to evaluate it, but I don't think I'm willing to build live with that big of boxes. Sonotube is the only ported option I'll consider again.

I'd really appreciate if someone can tell me if my model is wrong. Am I missing something? Will new Ultimax be better than my 15-year-old RL-P15? Any other good options for big subs. Mostly for movies. I cross to the Khans at 50 - 60hz .

Parameters I found on Google for my RL-P15

Soundsplinter RL-p15 D2
Fs	23.43	Hz
Re	3.66	Ohm
Qms	4.03
Qes	0.36
Sd	806.0	cm2
Vas	163.0	l
Xmax peak	24.60	mm
(Le)		mH
(Le2)		mH
(Re2)	0.00	Ohm
Nominal Power	650.0	W

Dayton Ultimax 18-22 18"
Fs	19.50	Hz
Re	4.40	Ohm
Qms	3.82
Qes	0.62
Sd	1219.0	cm2
Vas	212.0	l
Xmax peak	22.00	mm
(Le)	2.22	mH
(Le2)		mH
(Re2)	0.00	Ohm
Nominal Power	650.0	W

thanks.

[Bear]

Looks like the Qts on the 15" is quite a bit lower than the 18". One note about Unibox, other simulators will depress the SPL curve as Qts decreases, but leave the 20Hz intercept the same. Unibox will model increased SPL at the bottom end as Qts decreases (i.e., it's just the rolloff from the "steady state" SPL). If you plug this into WinISD, you might see a bigger difference.

Also note that anything above 80 - 100Hz for either one is illusory. You aren't going to cross either one at 350Hz, so the extra headroom on the 15" is realistically just more room for EQ (e.g., shelving filter).

[CADman_ks]

So, I don't know if this is helpful or not, but here goes...

First off, I don't have any of the speakers or drivers that you've listed. But, I recently did build this PE sub:

https://www.parts-express.com/Dayton-Audio-12-Reference-Series-HO-Subwoofer-and-Cabinet-P-300-7092

with a ho-hum 500W plate amp that was on sale at the time.

This setup is obviously NOT what you're talking about here, with duals, and only 12's, but I have this in a room that is about 17' x 20' and completely open on one 17' end. Maybe I'm getting old, but the bass that this thing puts out is unreal. It puts out bass that you can feel in your chest, it can get the job done. I can't even imagine what two of these could do. I would think that the Ultimax drivers, in ANY size could outrun this setup that I have, because they have a lot bigger XMAX than the driver I used.

Now, for the box. I too, like you, am at a point in my life, where I like to build things, but I don't like to build things. I find myself getting lazy a lot of times, and buying put together kits, and then assembling them. Mind you, I have an AWESOME shop with an AWESOME of tools, and have the ability to make anything that I set my mind too. I was very impressed with the overall quality of the box, and it went together very quickly, tightly, and solid.

Whatever you decide to do, I could definitely recommend one of the knockdown kits. The only issue that I had with the kit was that the driver cutout wasn't quite big enough, like a 1/16" smaller on the radius, so I had to enlarge the hole, but that was easily done with a new router bit, that I now own.

Good luck in whatever you decide to go with!!!

[CADman_ks]

So, I don't know if this is helpful or not, but here goes...

First off, I don't have any of the speakers or drivers that you've listed. But, I recently did build this PE sub:

https://www.parts-express.com/Dayton-Audio-12-Reference-Series-HO-Subwoofer-and-Cabinet-P-300-7092

with a ho-hum 500W plate amp that was on sale at the time.

This setup is obviously NOT what you're talking about here, with duals, and only 12's, but I have this in a room that is about 17' x 20' and completely open on one 17' end. Maybe I'm getting old, but the bass that this thing puts out is unreal. It puts out bass that you can feel in your chest, it can get the job done. I can't even imagine what two of these could do. I would think that the Ultimax drivers, in ANY size could outrun this setup that I have, because they have a lot bigger XMAX than the driver I used.

Now, for the box. I too, like you, am at a point in my life, where I like to build things, but I don't like to build things. I find myself getting lazy a lot of times, and buying put together kits, and then assembling them. Mind you, I have an AWESOME shop with an AWESOME set of tools, and have the ability to make anything that I set my mind too. I was very impressed with the overall quality of the box, and it went together very quickly, tightly, and solid.

Whatever you decide to do, I could definitely recommend one of the knockdown kits. The only issue that I had with the kit was that the driver cutout wasn't quite big enough, like a 1/16" smaller on the radius, so I had to enlarge the hole, but that was easily done with a new router bit, that I now own.

Good luck in whatever you decide to go with!!!

[---k---]

Also note that anything above 80 - 100Hz for either one is illusory. You aren't going to cross either one at 350Hz, so the extra headroom on the 15" is realistically just more room for EQ (e.g., shelving filter).

Yes. Thanks for the reminder. IIRC, when I was first building these way back, ThomasW said something along the lines of we don't care about the models, we care about how much room there is for EQ. He was an early proponent of EQ to fill in.

The Ultimax would definitely have more room for EQ. The RL-P15 was starting to run out of excursion at 650W, but mostly below 20hz... I'm not sure how crazy I'm going to go with EQ. I need to investigate how much boost Audseyy may be giving me, if any or if it is all room gain. Unfortunately, my current receiver is too old to support the app that'd let me see it exactly. I guess I could get out the measurement gear, but I'm not sure anything I have is compatible with the current computers.... Or my time availability.

So, I don't know if this is helpful or not, but here goes...

First off, I don't have any of the speakers or drivers that you've listed. But, I recently did build this PE sub:

https://www.parts-express.com/Dayton-Audio-12-Reference-Series-HO-Subwoofer-and-Cabinet-P-300-7092

with a ho-hum 500W plate amp that was on sale at the time.

This setup is obviously NOT what you're talking about here, with duals, and only 12's, but I have this in a room that is about 17' x 20' and completely open on one 17' end. Maybe I'm getting old, but the bass that this thing puts out is unreal. It puts out bass that you can feel in your chest, it can get the job done. I can't even imagine what two of these could do. I would think that the Ultimax drivers, in ANY size could outrun this setup that I have, because they have a lot bigger XMAX than the driver I used.

Yeah, you're getting old. :P My old room was similar 17'x17' and I can't imagine one little sealed being enough. In my old room, I moved the these RL-p15s from sealed boxes to a big ported to get even more of that earth moving low end. You really don't know what you're missing. But, atlas I must be getting old too, because here I am saying I'm happy enough in an even bigger room back with my two sealed boxes.

A lot of that chest thumping bass is up higher in the bass frequency range, around 50 - 60 hz, where you're current sub likely excels. It is that extended low bass, where your sub is rolling off, that produces more floor floating rumble that the big monsters will give you. FWIW, off the top of my head of demos, see if you can find Finding Dori. There is a scene in it where a little girl taps the glass of the fish tank. With my old ported sub, calibrated correctly so the bass was level with the mains, my whole room felt like it was collapsing in. It really felt like what you'd imagine being inside a fish tank with someone tapping on the glass and the echo coming from all around you... I don't know if this scene is demoing what I'm explaining, but it is something to behold. Super fun if you're into that type of thing.



So, no good answer yet. I saw Jon mention quality of bass from the Ultimax that he's built for friends. I was hoping he might chime in.

I just can't believe the models are that close between a long-throw 15 and long-throw 18".
And
I'm just not sure what other options are out there. The 18" RS HO is interesting, but with it's low xmax, I'd probably want 4 to improve on my current, and that is a lot of box. I've seen people singing praises of an Eminance monster, but it looks like it needs a lot of EQ and is expensive.


I will likely focus on upgrade the receiver next to something that passes 4k, build some Atmos speakers for in the ceiling, then think about subwoofers. Subs are just more fun for me to think about than receivers and ceiling speakers.

[CADman_ks]

...
Yeah, you're getting old. :P My old room was similar 17'x17' and I can't imagine one little sealed being enough. In my old room, I moved the these RL-p15s from sealed boxes to a big ported to get even more of that earth moving low end. You really don't know what you're missing. But, atlas I must be getting old too, because here I am saying I'm happy enough in an even bigger room back with my two sealed boxes.

A lot of that chest thumping bass is up higher in the bass frequency range, around 50 - 60 hz, where you're current sub likely excels. It is that extended low bass, where your sub is rolling off, that produces more floor floating rumble that the big monsters will give you. FWIW, off the top of my head of demos, see if you can find Finding Dori. There is a scene in it where a little girl taps the glass of the fish tank. With my old ported sub, calibrated correctly so the bass was level with the mains, my whole room felt like it was collapsing in. It really felt like what you'd imagine being inside a fish tank with someone tapping on the glass and the echo coming from all around you... I don't know if this scene is demoing what I'm explaining, but it is something to behold. Super fun if you're into that type of thing.

...

That would be an interesting test, Finding Dori, and I'm sure that you're right that my sub is NOT producing that floor shaking bass that you're talking about, as for your chest, it feels like you're being hit.

For me, however, the struggle is real. Not with me, but the dear wife. She wouldn't let us listen to the SuperBowl with the sub on, because it was too much, and there wasn't ANYTHING going on there. My kids came to my rescue, and we got to leave the sub on... SMH...

[5th element]

You hit the nail on the head with the 'how much room for EQ' thing. That says the same thing but in a different way to - how do things look if you have unlimited power and run these into Xmax instead? Then you'll see what the Ultimax 18" will give you vs what you have now.

If you really want something that will dig deeper/go louder without the need for EQ, or for additional power, then you're only option is to go vented, or with PRs.

The RL-p15s, with an XBL2 motor, are going to be solid performers there isn't any real reason to replace these. Another option would be to buy some PE boxes and PRs. That will give you real gains down where it counts. What does the performance of the RL-p15 look like in ported/PR boxes?

[Bear]

Yes. Thanks for the reminder. IIRC, when I was first building these way back, ThomasW said something along the lines of we don't care about the models, we care about how much room there is for EQ. He was an early proponent of EQ to fill in.

The Ultimax would definitely have more room for EQ. The RL-P15 was starting to run out of excursion at 650W, but mostly below 20hz... I'm not sure how crazy I'm going to go with EQ. I need to investigate how much boost Audseyy may be giving me, if any or if it is all room gain. Unfortunately, my current receiver is too old to support the app that'd let me see it exactly. I guess I could get out the measurement gear, but I'm not sure anything I have is compatible with the current computers.... Or my time availability.

Instead of holding the box volume constant. Play with the Qts, and let the box volume float. Heavy fill and 711L will get you a Qts of 0.577 (Bessel). The way Unibox will model it, you will see a significantly higher value at 20Hz using 650W of power (~109dB). So, if you compare the drivers with the same Qts, the differences you are expecting will show up. After that, your new best friend is the Linkwitz transform. And a LOT of amplifier power, potentially, depending upon where you want to land (additional power compensates for the missing box volume -- TANSTAAFL).

Unibox will take an LT input, but I've never done that.

[---k---]

You hit the nail on the head with the 'how much room for EQ' thing. That says the same thing but in a different way to - how do things look if you have unlimited power and run these into Xmax instead? Then you'll see what the Ultimax 18" will give you vs what you have now.

Totally. Yesterday, I had played with the model a little to look at 650w vs 1000w. And even played some with EQ circuits. But, I didn't save the graphs and somehow I lost even my driver inputs.... But, then I'd be upgrading the amp too.... Getting expensive.

The RL-p15s, with an XBL2 motor, are going to be solid performers there isn't any real reason to replace these.

I'm not sure if that is what I wanted to hear or not. In some respects, it feels good to have confirmation that there haven't been any big leaps that rendered my 15-year-old drivers outdated junk. But, it's sad because it doesn't leave me with a good excuse to upgrade.

Ports, PR are always options. I've done it. It is fun. I'm getting old and there is something to like about the simplicity of a sealed box. ... I think our hope is after covid, we're going to try and find a contractor to move the laundry area and wall it off... Maybe I should go back to my dream of a big IB at the back of the room.... that of course would be in addition to to big subs up front.

[Steve Manning]

Hey Ryan, don't know if you have ever seen this idea, https://www.theabsolutesound.com/art...bwoofer-system. I've seen multiple subs being recommended by a number of companies to help with room modes and what not.

[Scottg]

You could try actuators in your seats.. I did this for my modest HT setup (..with a mono dipole sub). The combined effect for me is very similar to a real theater (and a large one at that) - it sounds quite different than any typical HT (which is highly pressurized by comparison).

I use 2 of these per recliner for each part of the chair (base and back). It did require modification to do it right though, including "floating" isolation from the floor.

https://www.parts-express.com/Dayton-Audio-BST-1-High-Power-Pro-Tactile-Bass-Shaker-50-Watts-295-244

[kingpin]

Yes. Thanks for the reminder. IIRC, when I was first building these way back, ThomasW said something along the lines of we don't care about the models, we care about how much room there is for EQ. He was an early proponent of EQ to fill in.

The Ultimax would definitely have more room for EQ. The RL-P15 was starting to run out of excursion at 650W, but mostly below 20hz... I'm not sure how crazy I'm going to go with EQ. I need to investigate how much boost Audseyy may be giving me, if any or if it is all room gain. Unfortunately, my current receiver is too old to support the app that'd let me see it exactly. I guess I could get out the measurement gear, but I'm not sure anything I have is compatible with the current computers.... Or my time availability.




Yeah, you're getting old. :P My old room was similar 17'x17' and I can't imagine one little sealed being enough. In my old room, I moved the these RL-p15s from sealed boxes to a big ported to get even more of that earth moving low end. You really don't know what you're missing. But, atlas I must be getting old too, because here I am saying I'm happy enough in an even bigger room back with my two sealed boxes.

A lot of that chest thumping bass is up higher in the bass frequency range, around 50 - 60 hz, where you're current sub likely excels. It is that extended low bass, where your sub is rolling off, that produces more floor floating rumble that the big monsters will give you. FWIW, off the top of my head of demos, see if you can find Finding Dori. There is a scene in it where a little girl taps the glass of the fish tank. With my old ported sub, calibrated correctly so the bass was level with the mains, my whole room felt like it was collapsing in. It really felt like what you'd imagine being inside a fish tank with someone tapping on the glass and the echo coming from all around you... I don't know if this scene is demoing what I'm explaining, but it is something to behold. Super fun if you're into that type of thing.



So, no good answer yet. I saw Jon mention quality of bass from the Ultimax that he's built for friends. I was hoping he might chime in.

I just can't believe the models are that close between a long-throw 15 and long-throw 18".
And
I'm just not sure what other options are out there. The 18" RS HO is interesting, but with it's low xmax, I'd probably want 4 to improve on my current, and that is a lot of box. I've seen people singing praises of an Eminance monster, but it looks like it needs a lot of EQ and is expensive.


I will likely focus on upgrade the receiver next to something that passes 4k, build some Atmos speakers for in the ceiling, then think about subwoofers. Subs are just more fun for me to think about than receivers and ceiling speakers.

First time I heard that on my pair of 18" IXL's I almost shat myself when they started clanging.
Now with my dual 21's it's my favourite scene to demo. Now everyone else shats themselves and I sit here laughing.
I agree about the house carnage. There is a crack in my wall from the ceiling that I swear wasn't there originally.

[rick844]

I went with a GSG audio roundover marty cube setup with the 18" Dayton ho sub. Just one of these with a crown 1500 and it is more than enough low end to shake stuff in other rooms and yet has the chest punch i wanted. The HO 18" subwoofer really does well in the higher freq. And only gives up just a little on the low end. Highly recommend this setup.