[Teeeejay]

I'm looking to build dual 18s for my living room to replace my single Bic F12. The Bic F12 cannot do the lows as well as I want, and I'd like at least 2 subs to help with nulls. My current thought is to do UM18s or Lavoce SAF 184.03 for the build on a NX6000D. I'm not super interested in the VBSS since it doesn't dig as deep as I'd like.

One thing that I'm having trouble understanding for my specific scenario is how room gain might affect my system. I understand how room gain works (I've been a car audio guy for a while now). My living room is about 13x20 with a vaulted ceiling (8ft on the low end and 12ft on the high end). One of the smaller side walls opens up to the kitchen, but the rest of the room is enclosed.

My understanding is that the open wall will almost entirely eliminate room gain. The wall that my couch sits against is essentially a 48 foot wall since it runs the length of the house, and the open wall means my space is roughly 1500 ft^2 as far as the subs would be concerned. So no gain till ~12Hz. I just didn't know if the two parallel walls of the living room would lead to any gain.

If my understanding is correct, I think I'm going to build two Johnnysubs to help reinforce the lows. Mini marty would be a bit big for my space. If I can except some amount of room gain, I would probably go sealed since I know the ULF potential is better with DSP... Or maybe Johnnys with future plans for a BOSS platform.

Either way, I'm sure I'll be smitten with any setup since I'll have ~4.5x the surface area of the BIC, so output should be substantially better.

 

[Eskimo1]

I'm NO expert, but here's an idea: Take your current sub outside, run a sweep. Then bring it back inside, run another sweep. I'd think that should help show you what kind of room gain you're getting?

 

[Teeeejay]

I'm NO expert, but here's an idea: Take your current sub outside, run a sweep. Then bring it back inside, run another sweep. I'd think that should help show you what kind of room gain you're getting?

Not a bad idea honestly. I still have to get myself a UMIK (right now Audyssey does everything) so that could be a fun little exercise to learn how to use the thing.

How do you like your ported LaVoce? Are they able to hit the lows well? Modeling them in WinISD looks promising but I know they don't quite get the excursion of the UM18s.

 

[Chris Popovich]

LaVoce 214.50 and UM18 are essentially equal on the bottom end as far as displacement goes, with the LaVoce having tons more output in the upper bass. I'd assume the 18" version is bested by the UM18 down low displacement wise and again beats it in the upper bass. IMO you'll really need something more than Audyssey to maximize a pro driver as they need signal shaping in most rooms (in addition to room correction). Minidsp is the cheap & effective go-to, if you don't get one of the DSP amps.

Chris

 

[Teeeejay]

LaVoce and UM18 are essentially equal on the bottom end as far as displacement goes, with the LaVoce having tons more output in the upper bass. IMO you'll really need something more than Audyssey to maximize a pro driver as they need signal shaping in most rooms (in addition to room correction). Minidsp is the cheap & effective go-to, if you don't get one of the DSP amps.

Chris

Thanks for the insight. My plan is to get a NX6000D, so no worries with the DSP. I'm just using Audyssey now because it's better than nothing, and my AVR has XT32 which does a pretty good job.

I think I'm leaning more towards the LaVoce. I don't see as much info about it on the forums since it seems to be a relatively new driver, but it's cheaper than the UM18 and it seems output is overall better, and it seems to be a better performer in smaller boxes (martycube, johnny, etc). From my modeling, I'm seeing that the LaVoce is worse on output from 20Hz to about 33Hz, but only by at worst a little under 1db. Midbass output looks to be insanely better too.

This is my WinISD model, just want to post it here to see if it looks right. Green is the LaVoce, red is the UM18. 7.5 cubes, tuned to 18.5Hz.

 

[Eskimo1]

Not a bad idea honestly. I still have to get myself a UMIK (right now Audyssey does everything) so that could be a fun little exercise to learn how to use the thing.

How do you like your ported LaVoce? Are they able to hit the lows well? Modeling them in WinISD looks promising but I know they don't quite get the excursion of the UM18s.

My response is very good down to the tuning point. Impact is impressive. with the 6000 amp, I can't hurt 'em.

 

[Teeeejay]

My response is very good down to the tuning point. Impact is impressive. with the 6000 amp, I can't hurt 'em.

Good stuff. Comparing the Johnny and Mini Marty in WinISD... I might just have to go for the mini. The response is tons better. Lucky for me I have no WAF to deal with, but I also don't want my living room to be too overtaken by subs with something like a Devastator or Full Marty, haha.

 

[Vergiliusm]

Lucky for me I have no WAF to deal with, but I also don't want my living room to be too overtaken by subs with something like a Devastator or Full Marty, haha.

Where's the fun in that? Take advantage of the circumstances. Some of us aren't so lucky, and are limited to 3-4 cube(internal)boxes due to WAF.

 

[Teeeejay]

Where's the fun in that? Take advantage of the circumstances. Some of us aren't so lucky, and are limited to 3-4 cube(internal)boxes due to WAF.

I suppose you're right. The full marty is only 8 inches taller than the mini, and who cares about vertical space anyway? I've already scope creeped myself out of doing sealed 18s so may as well go all out. Lmao

 

[Eskimo1]

I suppose you're right. The full marty is only 8 inches taller than the mini, and who cares about vertical space anyway? I've already scope creeped myself out of doing sealed 18s so may as well go all out. Lmao

I did the mini's only because I was buying 4 at a time, and wanted to use the rears as end tables.

 

[Teeeejay]

I did the mini's only because I was buying 4 at a time, and wanted to use the rears as end tables.

Fair enough. I think the full Martys will be kind of silly in my living room, but fuggit, one day when I have a dedicated theater they'll be awesome.

 

[noah katz]

I just didn't know if the two parallel walls of the living room would lead to any gain.

I think room gain is more a function of the enclosed volume seen by the subs.
The walls will give you some nice modes though

Take your current sub outside, run a sweep. Then bring it back inside, run another sweep.

A close-mic measurement of the sub might get close to that.


As for lack of a mic, how about do some Audyssey runs and compare the "before".

 

[Chris Popovich]

Minor correction; the SAN214.50 is roughly equal to the UM18 down low and beats it above, the 214.50 is the 21" version, not sure about 18". I'd probably still go LaVoce but run a couple more of 'em.

 

[Teeeejay]

Minor correction; the SAN214.50 is roughly equal to the UM18 down low and beats it above, the 214.50 is the 21" version, not sure about 18". I'd probably still go LaVoce but run a couple more of 'em.

Haha, reading this forum is dangerous. Originally I thought I'd be happy with something like a single VBSS and now here I am........ Then I see some of these guys running like 16 sealed subs and getting flat to 1Hz. Insanity.

I need to start picking cheaper hobbies... my other big hobbies are cars and computers.

 

[Chris Popovich]

Yeah. I get it. Started out wanting dual 18's because I was tired of overdriving my subs. Skipping writing about a few middle steps I took, now I'm looking at 8 21" drivers with 8 21" passive radiators in my music only system in the living room with ~8800 watts if I can pull it from the wall. What I'm doing could be done much cheaper but not anywhere near as awesome. If you want the tortured logic path, it goes like this:

1: I want high output clean deep bass.
2: I regularly listen to music that has infrasonic content at high levels.
3: I regularly employ a subharmonic synthesizer on some of the music that doesn't have infrasonic content, and it makes it have infrasonic content
4: I want high output capability at the listening position(s)
5: I want low distortion at the listening position when pushing things.
6: I want to smooth room modes effectively. This means multiple subs.
7: I am limited on max current able to be pulled from wall so need some sensitivity

Anyway that lead me down the road.

So IMO try to look forward a bit. If you're inclined to overdo stuff (don't have to admit it out loud mind you), then perhaps starting with something that may be a touch less optimal by itself but will play into a modular build over time will make more sense.

 

[Teeeejay]

Yeah. I get it. Started out wanting dual 18's because I was tired of overdriving my subs. Skipping writing about a few middle steps I took, now I'm looking at 8 21" drivers with 8 21" passive radiators in my music only system in the living room with ~8800 watts if I can pull it from the wall. What I'm doing could be done much cheaper but not anywhere near as awesome. If you want the tortured logic path, it goes like this:

1: I want high output clean deep bass.
2: I regularly listen to music that has infrasonic content at high levels.
3: I regularly employ a subharmonic synthesizer on some of the music that doesn't have infrasonic content, and it makes it have infrasonic content
4: I want high output capability at the listening position(s)
5: I want low distortion at the listening position when pushing things.
6: I want to smooth room modes effectively. This means multiple subs.
7: I am limited on max current able to be pulled from wall so need some sensitivity

Anyway that lead me down the road.

So IMO try to look forward a bit. If you're inclined to overdo stuff (don't have to admit it out loud mind you), then perhaps starting with something that may be a touch less optimal by itself but will play into a modular build over time will make more sense.

I definitely can be the type to overdo things. My Jeep and Subaru both got the "overdone" treatment. My original thought was to just do two sealed UM18s. Nice, easy setup. Can still hit the lows with some DSP. Easy to blend more subs later if I want to make subwoofer end tables or something to fire into the sofa and smooth the room nodes better.

Then I kept reading and saw info about the LaVoce subs and how they seem to have similar performance with more midbass. So then I started thinking about going ported to raise the low end to balance out the big increase in midbass... and now we're here lol.

I'm sure this will all lead to me DIYing speakers too. Right now I have cheaper speakers (Fluance SX-6) but they sound decent compared to the Bic F12. But I'm sure with a sub upgrade I'll start to realize how lacking they are.

I'm basically stuck in a great vacillation. Haha.

 

[Teeeejay]

I guess I should clarify in all this sub talk, my living room TV is used 75% for gaming, 20% movies, and maybe 5% music, but only sometimes and it's when I'm in the kitchen cooking and I'm the only one home (a few friends rent bedrooms from me). So powerful midbass isn't super important, though a lot of the games I play are JRPGs with great soundtracks so I don't want music to sound like total crap. That's why to me the LaVoce seems like a great setup. Midbass isn't as strong as VBSS and lows aren't as strong as a UM18, but I can get somewhere in the middle I think and be really happy.

 

[Chris Popovich]

I'm not sure the midbass with LaVoce wouldn't be superior. The PA460 is a great value but not what I'd call a high performance woofer.

 

[Teeeejay]

I'm not sure the midbass with LaVoce wouldn't be superior. The PA460 is a great value but not what I'd call a high performance woofer.

You might be right. I'll have to check my WinISD model again. I suppose the appeal of the VBSS is that it's so cheap that you can cheaply run 4+, vs a better woofer you might want to limit yourself to 2 or 1.