Nearfield bass cabinet with multiple woofers for HT - AVS Forum | Home Theater Discussions And Reviews
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post #1 of 108 Old 11-25-2016, 09:57 PM - Thread Starter
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Nearfield bass cabinet with 2 PA380s and 1 Ultimax 18

I'm planning on building a cabinet and disguising it as a piece of buffet/server/sideboard furniture in our living room with fake drawers and cabinet doors. It will sit behind the couch with the subwoofers and the ports firing into the back of the couch.



Here's an example of something like what I want. Overall dimensions 20Wx30Hx70L (inches).




This will give me a roughly 20ft2/550l of volume. Don't want it too much bigger, but could go to 80L and/or 22W to add 5ft2 or so.



My goal is to have solid low-bass and good mid-bass, 50/50 movies & music. It will be my primary source for LFE, I don't plan on having any other subs in the room for now. Currently I have a 15" ported Def Tech and a Def Tech Supercube Reference 14" 1000 watts with dual passive radiators. These have a lot of bass down to about 20hz, but I want more and I want more punch in the mid-bass which my system is lacking.
I would love to have significant Tactile Response across the bass frequencies. In a previous setup, I had really good TR in the mid-bass and I've really been missing it (I had a pair of JBL S312s and a Klipsch RSW-10d).

Our living room is about 10x20x8 with an opening to the dining room (12x12) which has an open doorway to the kitchen and a small 6 foot hallway. Not too big, but pretty open. The floor is suspended and has carpet. I've had subs on the front wall before and they seem boomy up there, that's the main reason I moved them nearfield behind the couch.

So I've read the VBSS thread and the Nearfield MBM thread and others. I really like the idea of one or two mid bass cabinets. Additionally I really want to combine all the sub cabinets into one piece of furniture. Basically I'd like a large ported volume for low freqs and one or two smaller ported volumes for mid bass punch and TR. I like the PA460 and the Ultimax 18.
My plan for the Ultimax 18 is a Marty sized volume (11ft2) or larger tuned to 16-18hz (Q1 - this should be better than my two Def Techs. Does that seem like a reasonable expectation?)

Like I said I really like the PA460, BUT for my plans I am leaning towards a pair of PA380s. My mean reasoning is that I want to spread out the mid bass punch across the cabinet since it will be sitting behind the couch, that way all seats will have comparable TR. So, to get to the meat of the post, here is one way I pictured the layout. I like having the two MBMs higher up at chest level and balanced so the cab is symmetrical.



I initially imagined the UM18 laying flat on the bottom of the cab downfiring, since the cab will have 3-4" feet on the bottom. But if I can I think I would prefer the driver on the back, also firing into the couch. So, all the ports and all the drivers on the back side of the cabinet is what I'm thinking right now. I drew the sketches with round ports, but I'd be just fine with slot ports too (in fact I drew a few sketches with square ports) and I really want to keep it symmetrical.

I think the PA380s (each) would work in a volume anywhere from 1-3ft2 and tuned somewhere around 40-60hz. That should leave me about 11-15ft2 for the large volume for the UM18. This should offer significant extension and good low frequency output. (Q2 - I'm worried about the PA380s overpowering the UM18)



The iNuke 3000DSP is my first choice for amp. Should be enough power, and I'll need the DSP for all the crossovers and tuning. UM18 wired for 4 Ohms on one channel and the PA380s in parallel for 4 Ohms on the other channel.

I'm pretty excited, haven't bought any parts yet, just getting my ducks in a row about what I want.
So, any suggestions or recommendations are certainly welcome. (especially on Q1 and Q2 in the text above)
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Last edited by Brazle; 11-25-2016 at 10:14 PM.
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post #2 of 108 Old 11-25-2016, 10:02 PM - Thread Starter
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Here are a few of the other design ideas I had while putting my ideas together:

I thought I wanted sealed on the bottom and was looking at the 1260s and other 12" options for the MBM.
Spoiler!

In early designs I was leaving room in the top 6" for the amp, I wanted a separate cabinet space there to hide the amp. But I got worried it would overheat and when I turned to a ported volume for the low frequencies I needed more space in the cabinet.
Spoiler!

Played with the idea of 3 VBSS cabinets, or two tuned low and two with smaller drivers for MBMs.
Spoiler!

Making room for the Marty volume, and I wanted everything firing into the back of the couch. Couple of ideas to optimize TR from ports and drivers.
Spoiler!

Just a few final tweaks and ideas for a UM18, a PA460 and two PA380s.
Spoiler!
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HT setup: Vizio 50" 4K | Xbox & PS3 | Pioneer Elite VSX-94TX | Bose 701 towers (V1) | JBL S Center | Def Tech Reference SuperCube & DIY Nearfield cabinet ported UM18 dual ported PA380 ULF+MBM

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post #3 of 108 Old 11-26-2016, 04:42 AM
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I'm excited about this project. Looks very interesting. When I was deciding on a nearfield MBM, I was looking at the PA460, PA380 and PA310. Here are the dimensions that I was looking at:




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post #4 of 108 Old 11-26-2016, 05:01 AM
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Subscribed - I have a similar setup and just started looking into options for the same.

However it doesn't look like I will be going as elaborate as you. I was initially thinking a couple of sealed UM-18's (each in its own box) and buy/build a table or fake cabinet to camouflage the subs. That will allow me some other placement options in the future.

However I really like what you are going for. Keep us posted!

I turn the sharpness on my TV all the way up, because that's how I like my picture... real sharp.
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post #5 of 108 Old 11-26-2016, 08:42 PM - Thread Starter
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Quote:
Originally Posted by Steve Kuester View Post
I was initially thinking a couple of sealed UM-18's (each in its own box) and buy/build a table or fake cabinet to camouflage the subs. That will allow me some other placement options in the future.

However I really like what you are going for. Keep us posted!
Thanks Steve! It seems like the UM18s would be great in a sealed box too. Those would be easier to place around the room.

Quote:
Originally Posted by VicTorious1 View Post
I'm excited about this project. Looks very interesting. When I was deciding on a nearfield MBM, I was looking at the PA460, PA380 and PA310. Here are the dimensions that I was looking at:
Hey Vic, hope you get your issues with your MBMs figured out soon. I'm curious about the Tune Frequencies you listed for the 460, 380 and 310 models. They seem lower than I would expect for an MBM. Did you choose those tunes because they modeled better with lower tunes or is there another reason?

HT setup: Vizio 50" 4K | Xbox & PS3 | Pioneer Elite VSX-94TX | Bose 701 towers (V1) | JBL S Center | Def Tech Reference SuperCube & DIY Nearfield cabinet ported UM18 dual ported PA380 ULF+MBM
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post #6 of 108 Old 11-26-2016, 10:29 PM - Thread Starter
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I just ordered a NU6000DSP! They are only $339 on Amazon right now. Couldn't pass up that deal.
FYI, the inuke 3000DSP is on sale right now too for $239 I believe.
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post #7 of 108 Old 11-27-2016, 12:24 AM
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Quote:
Originally Posted by Brazle View Post
Hey Vic, hope you get your issues with your MBMs figured out soon. I'm curious about the Tune Frequencies you listed for the 460, 380 and 310 models. They seem lower than I would expect for an MBM. Did you choose those tunes because they modeled better with lower tunes or is there another reason?
Thanks, Brazle. Still troubleshooting my MBMs. I might swap out this 1000dsp for a 3000dsp. The tune frequencies I listed above are slightly lower than how those sized boxes were actually modeling. For the 460, with that sized box and vent length, I believe the tune is right around 40hz. I think there is a similar bump in the actual tuning frequency numbers for the other subs as well.
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post #8 of 108 Old 11-27-2016, 09:41 AM
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I have a 9cuft ottoman in from of my living room seating right now with a sealed downfiring 18" driver that's a mid bass monster! Best thing I ever added as there's little to no room mode excitation as it's in the middle of the room. The foam and upholstered cover never gives up what's inside! I laminated the original 1/2 plywood with another 1/2 of lite poplar ply with green glue and added some bracing and a 3/4" baffle board.
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post #9 of 108 Old 11-27-2016, 10:49 AM
 
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With that much cab size you could do a Tuba HT low profile, saving you a lot of $$$ on drivers and amps. Here's a build thread:
https://community.klipsch.com/index....-build-thread/
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post #10 of 108 Old 11-27-2016, 11:38 AM - Thread Starter
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Quote:
Originally Posted by mayhem13 View Post
I have a 9cuft ottoman in from of my living room seating right now with a sealed downfiring 18" driver that's a mid bass monster! ... I laminated the original 1/2 plywood with another 1/2 of lite poplar ply with green glue and added some bracing and a 3/4" baffle board.
That sounds like a cool piece. So is this your only source of LF or do you have other subs? What kind of driver are you using? I'd love to finish mine similar to yours. Do you have any pics or a build thread?

Quote:
Originally Posted by Bill Fitzmaurice View Post
With that much cab size you could do a Tuba HT low profile, saving you a lot of $$$ on drivers and amps. Here's a build thread:
https://community.klipsch.com/index....-build-thread/
Thanks for the suggestion, I did read a lot about horns vs ported vs sealed designs. I sort of ended up on ported because I was worried about difficulty with the horns and worried about spending $$ on amps for sealed. But in the thread you posted the guy says:
"Building this sub is not hard, follow the assembly instructions in order and it will go very smooth. The plans are well thought out and have plenty of pic's. Bill does a great job of explaining everything step by step. If you are limited in tools use the jig plans he has,it will be very helpful. A+ on plans!!"

So, maybe I'll take another look at the horns. I know they can get more output with less amp and less driver, I guess I saw some wavy Freq Responses and the boxes look complex, so that scared me off a bit.

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post #11 of 108 Old 11-28-2016, 06:20 PM - Thread Starter
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One day shipping on amps from parts-express! Yes please and thank you.
Got my 6000 in only 42 hours after placing the order with free shipping. Now I get to play around with it, even though I don't have a box and I don't have any sub drivers.

Well, I guess I'll just have to hook them up to my mains and see how they do. They're Bose 701 towers .... always done pretty well from a receiver, but maybe I'll get a little more out of them with a separate amp. Around 8 Ohms if I recall correctly, 200-400watts or whatever.
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post #12 of 108 Old 11-28-2016, 07:43 PM
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Very cool look forward to this build.

@3ll3d00d is building something similar where he has one cab, but multiple tunes for ulf and midbass
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post #13 of 108 Old 11-29-2016, 02:26 AM
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my design is in Ported NF UXL-18 Build (thread title is a bit misleading)

it's a 6th order bandpass, really it's an experiment for trying to maximise TR alone
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post #14 of 108 Old 11-30-2016, 11:23 AM - Thread Starter
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Quote:
Originally Posted by 3ll3d00d View Post
my design is in Ported NF UXL-18 Build (thread title is a bit misleading)

it's a 6th order bandpass, really it's an experiment for trying to maximise TR alone
Yea, I saw your thread that looks like a really cool design. I hope it works out the way you've designed it. Max TR would be great :-)
@derrickdj1 's Bumbuster looks pretty good too. Might be pretty close to what I'm designing - UM18 in a plus sized Marty for more extension. At least for my ULFs.

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post #15 of 108 Old 11-30-2016, 01:54 PM
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I have a large sectional couch and it is the only nearfield sub for me. Behind the couch it looks like a sofa table and does not look odd.
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post #16 of 108 Old 12-04-2016, 11:38 PM - Thread Starter
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Just started playing around in SketchUp this weekend and made a rough model of my cabinet. Just guessing on the ports and stuff, just throwing them where and how it looked good. Obviously it's a cutaway so the top and back of the box (actually it will be the front of the cabinet) are not drawn here so you can see the inside.







Any objections to the slight T-shape of the big ported volume the UM18 will be in?

Then I went over to my brother-in-law's house to look at some wood planks I had helped him get. He had glued them together for a desk for his mom, but she wanted a different desktop, so this was unused. He even cut it to the length I'm designing :-) We're just going to cut it down the middle so it's 70"x24" and then plane it, sand it and finish it. That'll be the cabinet top. And that gives me the basic dimensions of the box: 68"x22"x25" with 4" feet on the bottom and the slab on top with about 1" overhang.

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HT setup: Vizio 50" 4K | Xbox & PS3 | Pioneer Elite VSX-94TX | Bose 701 towers (V1) | JBL S Center | Def Tech Reference SuperCube & DIY Nearfield cabinet ported UM18 dual ported PA380 ULF+MBM

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post #17 of 108 Old 12-15-2016, 07:55 AM - Thread Starter
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I'm still playing around with dimensions for my cabinet. And I've got my first PA380 coming in today (hopefully). I'm curious how these drivers will sound in different cabinets so I've started building an MBM test box to put the PA380 in to try various tunes and see which I want to go with.
Basically I will change the volume of the box and the length of the ports to adjust the tune, see how close those are to the WinISD predictions and see if the give me the sound I'm looking for. Midbass punch mostly. How much of the interior volume needs to be dedicated to the MBMs will determine the design of the rest of the box, so I need to this before I can finish the rest of the design of the box. Ideally the UM18 would have as much volume as possible, so that's what I'm aiming for. If the MBMs need 3cu ft, so be it, but if they do just fine with 1.5 cu ft, then that gives me extra volume for the UM18/ULF part of the cabinet.

First test box will be ~3 cu ft, with two triangle 5"x5" ports, 5" long. Then I can just close one of the ports to change the tune from ~52Hz to ~37Hz. :-) I'm pretty excited just to see what it does.

Here's the design:


And here are my cuts - first time using a router I borrowed from a friend, pretty cool, but kind of scary too when that thing spins up.




And all the cut pieces ready to glue together tomorrow


Now I just need to go to Harbor Freight and get some long clamps and maybe a couple more router bits like a round off.
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post #18 of 108 Old 12-16-2016, 07:06 PM - Thread Starter
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Got a few pieces glued together:


And I got to play with my roundover bit. Very fun!


Also, got my first driver in. Dayton PA380. Gonna do some tests with this one before I order any more and before I finish my total cabinet design.
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post #19 of 108 Old 12-16-2016, 11:41 PM
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Interested to see how this turns out. Looks like something that might work behind my parents couch as a console table.
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post #20 of 108 Old 12-17-2016, 11:11 AM
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This going to be a really large cabinet. I think my 48 X 32 X 18 is a bit large. This should be interesting with the MBM built into the same cabinet. It may be a challenge getting everything tuned. Keep the pic's coming!

I opted for wheels on the cabinet for easy moving. They can be put far enough under the box so, not to take away aesthetics.
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post #21 of 108 Old 12-22-2016, 07:22 PM - Thread Starter
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Final composition of the first test box.



I'm using the PA380 driver.
http://www.parts-express.com/dayton-...oofer--295-034
I'm hoping to get some solid mid-bass action like others have been getting with the PA460s, just in a smaller package.



It's nothing fancy and for right now it's just a test box as I plan the design of my full cabinet which will house both LFE and MBM enclosures. I'm starting with a ~3 cubic foot box with dual triangular ports. Their total length is 5". They are right sided triangles with both right sides' lengths 5". If I'm not mistaken the cross sectional area of each port is 12.5 sq in. (5"x5" / 2 right?). The length of the port is from outer face to inner edge of the port. The three edges on the face and the one edge on the inside are all rounded over with 1/2" roundover.



My intentions are to compare various cabinet volumes and see if I could get away with a smaller volume for the pair of MBMs to make more volume for the LFE cabinet with UM18.
I believe the port will have some extension on the inside due to it sharing two of the interior walls of the box.
With both vents open WinISD says the box tune should be 52.7Hz. If I close one vent, WinISD says the box tune becomes 37.3Hz. I'm taking those as approximates an wanted to do my own testing and measurements to see which configuration I prefer.
3 Cu feet is what I've got now, ideally I'd go smaller like 1-2 cu ft. If I just cut it down to 1.5 cu ft I can use one port for a 53Hz tune (both ports open brings it up to 75Hz). again, this is just for testing.
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post #22 of 108 Old 12-22-2016, 11:42 PM - Thread Starter
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I did some fun tests today with my first setup of the MBM positioned near the place where the final cabinet will be. Directly behind the couch (MLP), halfway up covering lower back up to shoulders.
Click here to read my post on the The VibSensor Accelerometer Test Thread

Here's a comparison shot of the VS acceleration results showing how much the MBM adds in Tactile Response from 40Hz on up.

Before (no MBM)


After (with MBM high gain)


Note the huge increases between 40 and 100Hz for all three axes of acceleration. This thing comes on strong! Two should do just fine.

This was lots of fun and more importantly really felt great. The more I played with it, they more I felt the TR increase at the frequency ranges I was looking for. I've been missing a certain punch and I think mid-bass is the answer. Today was a good taste of what should be more satisfying mid-bass punch.
I spent some time trying PEQs to even/flatten out the response. I used an SPL meter just to make simple changes and then evaluated each one. My top scene that I'm trying to improve is the light cycle scene in Tron. Toward the end there is a five second shot where the music beats should hit as hard as punches. It's when the 2 good guys come up on either side of a bad guy and trap him between them and squeeze together to take him out. It's pretty short, but it's powerful. It's also probably low-mid-bass. BUT without the mid-bass punch it falls flat.
I also used the Terminator Salvation intro to gauge my progress and I think I still have a ways to go.
But, progress has been made and it feels good!

We're about to go on vacation for 2 weeks, so I really wanted to get something like this done before we leave. Now it may be some time before I can make progress. Thanks for the encouragement everyone. (and yes, @derrickdj1 it's going to be a pretty big cabinet :-)
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post #23 of 108 Old 01-20-2017, 01:26 PM
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NICE!

Planning something close to this myself.......will be taking notes !

Link to budget Home Theater build

http://www.avsforum.com/forum/19-ded...i-version.html
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post #24 of 108 Old 01-29-2017, 11:54 AM
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Hey, I was going to mention in our PM to check out the PA385 if you haven't but I figured I would post it here incase anyone else was looking at the two. In the future, if the PA380s are not enough it looks like you can get a good increase in output from the PA385 vs 380 in the same box and tune. They need more power though to do it and twice the price.

I use the max SPL chart to compare them, I think it is a little more accurate. It takes into account Xmax limits as far as I know which will be the drawback of the PA380.
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post #25 of 108 Old 01-29-2017, 06:15 PM - Thread Starter
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Quote:
Originally Posted by bscool View Post
Hey, I was going to mention in our PM to check out the PA385 if you haven't but I figured I would post it here incase anyone else was looking at the two. In the future, if the PA380s are not enough it looks like you can get a good increase in output from the PA385 vs 380 in the same box and tune. They need more power though to do it and twice the price.

I use the max SPL chart to compare them, I think it is a little more accurate. It takes into account Xmax limits as far as I know which will be the drawback of the PA380.

Hey @bscool ,
Thanks for sharing. I'll have to model the 385 and see how it looks, but yes I had picked the 380 due to price. I would be interested to know if there would be a significant upgrade in SQL going from the 380 to the 385. I just read the distortion can be pretty high on the 380. Hopefully I'll be using it in a higher frequency range where the distortion will be lower. Probably high pass it at 40Hz at least. Don't think I'll be getting anywhere near Xmax so I don't think I should be worried about distortion.

Update on my end:
#1 Ordered a UMIK-1 that should be here soon. Want to use it to try out the PA380 in different configurations. And also for room correction obviously.

#2 Got to spend a little time with just the PA380 running Saturday. I wasn't impressed at first, but maybe it's loosened up now. Felt more full and solid and smooth. With the 53Hz tune (both ports open) in ~3 cuft I had good output down to 40Hz. dB dropped off below 50Hz though. dB dropped a lot below 40Hz and port noise was severe below 35Hz. Again I would be using a 40Hz High Pass, so most of that is inconsequential.

I'm getting more and more confident that this setup will do exactly what I'm looking for.

HT setup: Vizio 50" 4K | Xbox & PS3 | Pioneer Elite VSX-94TX | Bose 701 towers (V1) | JBL S Center | Def Tech Reference SuperCube & DIY Nearfield cabinet ported UM18 dual ported PA380 ULF+MBM
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post #26 of 108 Old 01-29-2017, 07:03 PM
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Honestly, I don't know, I had been just going by modeling in WINISD and going by the assumption that the better-known brands would have good SQ so I just looked at how they compared for frequency response and max SPL. But now after starting to read and trying to learn more about what T/S parameters actually mean and tell you about a driver and how those T/S are derived, it is a freakin mess lol. It depends how the manufacturers T/S parameters were derived and if they are even accurate.

And also from modeling subs, I can see that just because a sub might not look the best in WINISD it might actually be one of the better soundings in real listening. An example is the LAB 15 it isn't the best modeling 15" sub in WINISD but in real life listening to me it is one of the best sounding subs I have heard myself.

http://www.diymobileaudio.com/forum/...-first%2A.html

I started reading these sections at the link today and my brain is in overload. A lot to take in. As for the 380 vs 385 I am assuming since they are both Dayton drivers and the one is twice the price of the other and has twice the excursion and they also had it Klippel verified that would be a better quality driver all around. I need to learn more about all of this.

1. First, read how to interpret the frequency response graphs:

How to interpret frequency response data

2. Next read how to interpret energy storage and why it's important:

Transient response and stored energy

3. Next read how to interpret distortion graphs and why it's important:

How to interpret distortion plots

4. Next read how to interpret a Klippel measurement and why it's important:

What to look for in a Klippel measurement

5. And it never hurts to understand what T/S parameters do for you:

T/S parameters... what are they good for?


This link has some interesting info too. My brain can't take it all in right now but it is on my to-read and understand list.

http://www.diymobileaudio.com/forum/...-analyzer.html

Last edited by bscool; 01-29-2017 at 07:14 PM.
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post #27 of 108 Old 01-30-2017, 01:25 PM - Thread Starter
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Got my UMIK-1 in today! Got it faster than expected, it wasn't supposed to ship out till today. Might do a little measuring today if I have time. Wife just left, I need to shower and I was planning to continue Dark Souls 3, but the mic is calling me...

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post #28 of 108 Old 02-04-2017, 11:42 AM - Thread Starter
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More updates!

1. Ordered my UM18 today (thanks @eng-399 for sharing the coupons!)

2. I've been getting to know REW and the UMIK-1 a bit this week. I'm pretty excited, I got some great numbers and graphs. Tons o' fun.

Set up in Main Listening Position:


First up just a couple of frequency response curves from my very first set of runs:
Red was first with L&R running full range (apparently I had left the bass boost at +2 at the receiver).
Blue was next with the subs and LR crossed over at 100Hz.



I know there's a lot going on here, but these are completely preliminary (with 1/6 smoothing, not L and R separate then averaged - I learned later that would have been better). Some pretty obvious ~50Hz mode boosting and lots of room gain below that. Also cancellation or something between 50 and 100 with subs and fronts. Weird. (gain on my MBM is set pretty low for these runs)

3. My next test was to see what my MBM is helping or hurting with. I did about 8 runs with the MBM set to various gain settings. This graph shows the two curves that mattered most to me.
Red is with the MBM off (gain set to 0)
Gold is with the MBM turned up to 75% (15 out of 20 notches on the iNuke)



Nice. I was worried I had set the MBM too high but it turns out I was much too low. I kept it around 6-9 notches on the iNuke so 30-40%. You can see matching to the subs required 15 notches - 75% gain on the iNuke.

4. Last but not least was to do the FR test of the MBM (one of the main reasons I broke down and got the UMIK)
A. First I tried an in-room FR with just the MBM at 1m distance on the floor in the living room (lots of boundaries and room modes) this is about the least useful graph I produced today. (I want to do another indoor test with the mic close the sub instead of 1m away to see how close I get to my outdoor graphs below - problem is you've got the port and the driver and averaging the two)
Update - did the indoor test with the mic and the graph is nowhere near the outdoor graph. :-(



B. Last I ran the MBM outdoors (ground plane). Here's the setup:



I built this box (~3 cu ft) with two ports with the intention to test and compare the two setups (high tune and low tune). According to WinISD: two ports = 54Hz tune, one port = 38Hz. Of course they are triangular ports so they will extend along two boundaries inside the cabinet which would drop the tune somewhat, so two ports = 49-54Hz, one port = 34-38Hz. There isn't much excursion around tune, so it was hard to tell by looking at minimum excursion what the tune was.

Update - I used the current measurements to find port tunes. Two ports = 46.5Hz, one port = 35Hz. Lower than I expected for sure. No problem.
So here are the two graphs overlayed:
Green = low tune ~35Hz with one port open (5"x5" triangle, length 5")
Blue = high tune ~46.5Hz with two ports open (two 5"x5" triangles, lengths 5")



I think his is the most valuable graph I got from my time today.

Here are the graphs from WinISD for comparison:



Next up I'll be cutting down my MBM box from 3 cuft to 2 or 1.5 cubic feet to do another response test for comparison (I thought about just throwing a bunch of 2x4s into the box to cut down the volume for testing, so I might do that).
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post #29 of 108 Old 02-04-2017, 12:03 PM - Thread Starter
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Also, shout-out and huge thanks to @jevansoh and @AustinJerry (and others) for the REW thread and setup instructions to get REW running smoothly!
Simplified REW Setup and Use (USB Mic & HDMI Connection) Including Measurement Techniques and How To Interpret Graphs

HT setup: Vizio 50" 4K | Xbox & PS3 | Pioneer Elite VSX-94TX | Bose 701 towers (V1) | JBL S Center | Def Tech Reference SuperCube & DIY Nearfield cabinet ported UM18 dual ported PA380 ULF+MBM
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post #30 of 108 Old 02-04-2017, 01:32 PM
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Quote:
Originally Posted by Brazle View Post
I'm planning on building a cabinet and disguising it as a piece of buffet/server/sideboard furniture in our living room with fake drawers and cabinet doors. It will sit behind the couch with the subwoofers and the ports firing into the back of the couch.
Very bad idea as this will most likely change the behavior in unforeseeable ways. If you want to have the full benefits of a real near field setup you should do something like this:

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