Hi all,
I've been working on many aspects of a new home theater setup and in the process have built a Full marty sub with an UM18-22.
I thought I'd go big as I could fit it in one corner of the room.
Upon testing, I don't think the corner is ideal, lots of nulls in the room, it's certainly powerful at certain frequencies at certain locations but I'd like to put some
more effort in and I think i'll go dual subs to help even things out.
If I go dual subs, I can't fit another full marty, so its either duall marty cubes, or i'm considering a sealed option.
I have the whole front wall I could use to position those subs, they will fit height wise to go anywhere along there.
I'm not completely sold on ported, as I probably use the system for maybe 70/30 music/movies.
If it's more for music, should I look more towards 2 x sealed subs for the SQ?
Current setup is NX6000D amp, minidsp 2x4hd.
Thanks heaps!
I've been working on many aspects of a new home theater setup and in the process have built a Full marty sub with an UM18-22.
I thought I'd go big as I could fit it in one corner of the room.
Upon testing, I don't think the corner is ideal, lots of nulls in the room, it's certainly powerful at certain frequencies at certain locations but I'd like to put some
more effort in and I think i'll go dual subs to help even things out.
If I go dual subs, I can't fit another full marty, so its either duall marty cubes, or i'm considering a sealed option.
I have the whole front wall I could use to position those subs, they will fit height wise to go anywhere along there.
I'm not completely sold on ported, as I probably use the system for maybe 70/30 music/movies.
If it's more for music, should I look more towards 2 x sealed subs for the SQ?
Current setup is NX6000D amp, minidsp 2x4hd.
Thanks heaps!
Greets!
Right, we normally want the speakers, listening position (LP and with tall speakers, ear height) at an odd harmonic in 3D.
It's a personal call like vented; for instance my corner loaded subs are tuned to ~14 Hz for the few pipe organ CDs that have some low B content and low enough for HT that in theory is limited to 20 Hz, yet many movies go much lower and probably the best reason overall to go sealed.
You're welcome!
Right, we normally want the speakers, listening position (LP and with tall speakers, ear height) at an odd harmonic in 3D.
It's a personal call like vented; for instance my corner loaded subs are tuned to ~14 Hz for the few pipe organ CDs that have some low B content and low enough for HT that in theory is limited to 20 Hz, yet many movies go much lower and probably the best reason overall to go sealed.
You're welcome!
https://www.parts-express.com/pedocs/specs/295-518--dayton-audio-um18-22-spec-sheet.pdf
what do you like these in now that the TS parameters have kind of sh!t the bed ( recently updated by Dayton ). I measured more like 31 hz Fs warm and decenty broke in on mine 🥲
what do you like these in now that the TS parameters have kind of sh!t the bed ( recently updated by Dayton ). I measured more like 31 hz Fs warm and decenty broke in on mine 🥲
Attachments
$%&#@! manufacturers that don't broadcast a revision and assign a revision suffix.
That said, their identical to ones I have from much earlier.............
That said, their identical to ones I have from much earlier.............
Yeah I have fallen victim to that. I Went with a full marty and the UM18-22 as it seems to be well regarded.
I have the newer specced version.
Don't know which way to go now.
I have the newer specced version.
Don't know which way to go now.
Old parameters: https://masori.de/products/ultimax-um18-22
fs is not everything. Dayton has stiffened the suspension (Vas: 212 --> 145 L) and made the cone lighter (mms: 655 --> 532 g). The motor strength has just decreased a little (BL: 23.8 --> 21.1 Tm).
Try modelling woofers with the different sets of TS parameters, to see how much the sound output really changes. Measure the parameters of your own woofer and model that one as well.
fs is not everything. Dayton has stiffened the suspension (Vas: 212 --> 145 L) and made the cone lighter (mms: 655 --> 532 g). The motor strength has just decreased a little (BL: 23.8 --> 21.1 Tm).
Try modelling woofers with the different sets of TS parameters, to see how much the sound output really changes. Measure the parameters of your own woofer and model that one as well.
Yep, 1x sub in a corner can be pretty uneven.
My recommendation would be to purchase either a USB measurement mic, or an audio interface and regular measurement mic, so you can figure out what's going on and optimise placement.
When considering real-world acoustics, the room will have time-based problems far in excess of what occurs in ported vs sealed. ie, once you've EQ'd them, the major difference will be cabinet size vs harmonic distortion, and whether you're happy to live with the fixed LF limit that ported boxes impose.
In a domestic situation, I typically go for sealed cabinets. A well-designed HiFi system won't be run hard enough for harmonic distortion to be a huge issue, but the compact size and continuous LF extension are both a bonus in that application.
Chris
2 sealed subs up front…….at least one in the back behind or beside the LP. Low pass the one closest to the LP the highest……low pass the fronts lower as fortification/overlapp. Oh…..you’ll need lots of power and for the front subs, fire them in to the enclosure, keep the magnet end out…..avoids thermal compression. This was suggested to me just recently so I tried it with an RSS390……..the Ashley amp clipped before the driver gave in……it actually made a significant improvement.
For music.
single 18 can work. kinda
Rather have sealed.
Depending on listening levels.
For music you always adjust bass levels with EQ anyways.
For movies.
Rarely watch.
Older movies. Its fine.
New movies, where you have to crank the volume
to hear dialog.
Then BLAM loud sound effects all rumble.
I ran 2x subs when I was more into movies.
So when the big BLAM or loud rumbles carried.
2x 12" was fine.
Little more cone/xmax to handle the wide dynamics.
and not flutter with the rumbling effects they use.
for rock or jazz dont really need sub.
For hard hitting electronic.
Id go back to my theatre setup with 2x 12"
But for people just watching movies.
Single 18" with 2 inches of travel.
Sure, actually rather just throw it in the corner actually.
The dayton is more than good for home use.
single 18 can work. kinda
Rather have sealed.
Depending on listening levels.
For music you always adjust bass levels with EQ anyways.
For movies.
Rarely watch.
Older movies. Its fine.
New movies, where you have to crank the volume
to hear dialog.
Then BLAM loud sound effects all rumble.
I ran 2x subs when I was more into movies.
So when the big BLAM or loud rumbles carried.
2x 12" was fine.
Little more cone/xmax to handle the wide dynamics.
and not flutter with the rumbling effects they use.
for rock or jazz dont really need sub.
For hard hitting electronic.
Id go back to my theatre setup with 2x 12"
But for people just watching movies.
Single 18" with 2 inches of travel.
Sure, actually rather just throw it in the corner actually.
The dayton is more than good for home use.
Well I decided to do some experimenting and i'm going to try both.
Ordered another UM18-22.
Built one sealed box and have it up and running, had already built one full marty and currently building another.
Then i'll build the 2nd sealed box.
So I guess I'll do some testing and see what i come up with 🙂
Ordered another UM18-22.
Built one sealed box and have it up and running, had already built one full marty and currently building another.
Then i'll build the 2nd sealed box.
So I guess I'll do some testing and see what i come up with 🙂
I recently fell over these data, because I had the old ones in my simulation. The new UM18-22 is a completely different driver.
Like they made the magnet gap an inch wide in the later production. The new one is on the "don't use it vented and closed only for a boom-boom system" list.
They practically made a very interesting driver a useless heap of metall. An 18" with TSP of 0.70 and an Fs in the 30's is a faulty construction with such a huge mms.
Sure, it will still move a lot of air, but not in a way someone would want it to. Did I get something wrong?
Like they made the magnet gap an inch wide in the later production. The new one is on the "don't use it vented and closed only for a boom-boom system" list.
They practically made a very interesting driver a useless heap of metall. An 18" with TSP of 0.70 and an Fs in the 30's is a faulty construction with such a huge mms.
Sure, it will still move a lot of air, but not in a way someone would want it to. Did I get something wrong?
I did find a write up by the guys at parts express as they got a few questions regarding this.
See below.
They don't seem greatly concerned.
https://techtalk.parts-express.com/...cabs-for-um18-22-t-s-parameters-way-off/page2
See below.
They don't seem greatly concerned.
https://techtalk.parts-express.com/...cabs-for-um18-22-t-s-parameters-way-off/page2
That dialog is ridiculous.
Low Fs ond low Qts are essential for the constuction of a vented cabinet. For buying or not buying a chassis. The Supermoderator basically said that in the oppinion of PE technical data don't matter. May it be 50% more here or 70% less there. Gives you an idea how they run their quality control...
Just like selling the same known to be faulty build plate amps over years.
With the sub chassis, the producer went for cheaper magnet material and larger VC gap to save on production cost. If you have a larger gap, you can use a cheaper/ worse build voice coil cone assembly and have less waste. Probaply because PE demanded lower wholesale prices...
Low Fs ond low Qts are essential for the constuction of a vented cabinet. For buying or not buying a chassis. The Supermoderator basically said that in the oppinion of PE technical data don't matter. May it be 50% more here or 70% less there. Gives you an idea how they run their quality control...
Just like selling the same known to be faulty build plate amps over years.
With the sub chassis, the producer went for cheaper magnet material and larger VC gap to save on production cost. If you have a larger gap, you can use a cheaper/ worse build voice coil cone assembly and have less waste. Probaply because PE demanded lower wholesale prices...
FWIW/YMMV, here in the USA, mobile audio increasingly 'drives' the market in general and specifically subwoofers.
Are you sure these Dayton's are really made in the US?
Maybe as a free air car sub for a school bus?
Anyway, a Qts of 0.70 or higher, as seen on some private measurements, makes a once 0.5 Qts driver unusable for vented cabinets.
In a simulation this may not be that easy to see, but the construction will not function as simulated and change parameters with power level.
For an open baffle it has a much too heavy cone.
It may be not that critical in the US, as it is offered at a quite low retail price of 300$. Now imagine you spent 600$ for it, like in Europe... that hurts.
I had this chassis on the list for a project. About 5dB less in a critical region, aside from the mentioned "doesn't work for vented" problem.
Maybe as a free air car sub for a school bus?
Anyway, a Qts of 0.70 or higher, as seen on some private measurements, makes a once 0.5 Qts driver unusable for vented cabinets.
In a simulation this may not be that easy to see, but the construction will not function as simulated and change parameters with power level.
For an open baffle it has a much too heavy cone.
It may be not that critical in the US, as it is offered at a quite low retail price of 300$. Now imagine you spent 600$ for it, like in Europe... that hurts.
I had this chassis on the list for a project. About 5dB less in a critical region, aside from the mentioned "doesn't work for vented" problem.
Well I've bought two of these at $700aud each. Originally not knowing about the spec changes. Funnily enough, the website even still lists the old specs. So I prob have a case for refunds etc, lot of stuffing around getting it back to them though.
I had asked a few questions on the AVS forum, where the MartySub main thread is, one of the more experienced guys said basically to just run with it.
I'm a bit of an amateur so its hard to know what to do. I thought I was doing the right thing by going big with the full marty, but the UM18-22 is really the only good driver I can source easily is Australia.
I had asked a few questions on the AVS forum, where the MartySub main thread is, one of the more experienced guys said basically to just run with it.
I'm a bit of an amateur so its hard to know what to do. I thought I was doing the right thing by going big with the full marty, but the UM18-22 is really the only good driver I can source easily is Australia.
It depends. If you run it closed in a large enclosure, have plenty of power and DSP it, that should not be much of a problem.
If you need the extra dB of a vented cabinet, you may not get what you build for. You can not exactly predict what it will do.
In general the room is the most important thing with a sub. In most cases you see too much bass at some frequency and have to lower the level. So the lack of some frequency may not exist in the room.
Measure them in room. This is most important thing to do before you decide anything.
If you build for vented, close it completely. The larger vented cabinet may compensate for the higher than promised Qts.
As you have two subs, you should normaly be able to DSP it for a nice response.
I don't know how your consumer laws are, but here, if technical relevant data (they are!) change and the seller is too lazy to correct his offer, you can return them. You don't have to proof that they don't work as a speaker... with more than 10% difference this is not acceptable. Have the PE moderator talk to your seller, as he offered a refund because of this problem.
If you need the extra dB of a vented cabinet, you may not get what you build for. You can not exactly predict what it will do.
In general the room is the most important thing with a sub. In most cases you see too much bass at some frequency and have to lower the level. So the lack of some frequency may not exist in the room.
Measure them in room. This is most important thing to do before you decide anything.
If you build for vented, close it completely. The larger vented cabinet may compensate for the higher than promised Qts.
As you have two subs, you should normaly be able to DSP it for a nice response.
I don't know how your consumer laws are, but here, if technical relevant data (they are!) change and the seller is too lazy to correct his offer, you can return them. You don't have to proof that they don't work as a speaker... with more than 10% difference this is not acceptable. Have the PE moderator talk to your seller, as he offered a refund because of this problem.
I seriously doubt it, but the distributors make the 'call' as to what makes the most $$$.
Not really, my neighborhood is primarily young folks with small 'boom box' fitted cars, trucks, etc., with large subwoofers, many with duals, quads. Factor in they have outdoor parties for every imaginable excuse to have one with trunk lids, doors open........ thankfully the local police quieted them down enough for my neighbors, though they didn't/don't bother me since my house is very well sealed to keep my up to ~120 dBs inside. 😉
Re the rest, 'preaching to the choir'! 😉
@Turbowatch2 In regards to a sealed enclosure, the standard flat packs are 4 cubic feet, what do you consider large in this scenario?
Thanks heaps
Thanks heaps