-yeah, this was the last one. 
I'd probably get a cat (Blue Russian or Siamese) if it weren't that one of my family had allergies to cat hair.
I wanted another Border Collie (the only breed I've had good luck with), but ended-up with an Alaskan Husky - and knew (and said) it was a mistake (overall), but the rest of the family wanted him..
On the "plus" side the car that hit it must have been doing quite a bit more than the posted limit (30 mph) in our neighborhood: hit it HARD (brutal damage) and mercifully was most assuredly a quick death. It's also not the first time that's happened on the road next to us (about 14 years ago - same thing happened).
Oh well, back to working on the HT.. (..I'm thinking about adding a dipole subwoofer.)
I'd probably get a cat (Blue Russian or Siamese) if it weren't that one of my family had allergies to cat hair.
I wanted another Border Collie (the only breed I've had good luck with), but ended-up with an Alaskan Husky - and knew (and said) it was a mistake (overall), but the rest of the family wanted him..
On the "plus" side the car that hit it must have been doing quite a bit more than the posted limit (30 mph) in our neighborhood: hit it HARD (brutal damage) and mercifully was most assuredly a quick death. It's also not the first time that's happened on the road next to us (about 14 years ago - same thing happened).
Oh well, back to working on the HT.. (..I'm thinking about adding a dipole subwoofer.)
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That seem to be like a big Luxurious home theater, movies and massages at the same time-yeah I'm still not sure what was up with the amp, but it seems to be working now. So that's good.
Turns-out the front "legs" of the platform (for the bass shaker) I built for each of the HT chairs was screwing-up the power-recline. "Mostly" fixed one (hack-job - literally), and now have several more to go.
..and a few minutes ago my dog was run-over (..got out while cleaning-up the mess on the HT side of the house), so that's not so great.
For me, a less than satisfactory weekend..
I'm hoping yours went a LOT better!
Ho Damn, sorry man, did your dog survived ?
Yeah for me it's Ok
I Read some more about REW and doing some more measurements, found out that nobody recommend to even try to run the it to get an accurate SPL level from driver, said it should be around 75db.
I tried using some cardboard to see if it made a difference and end up thinking that it's useless, lots of repeating patterns in the measurements probably due to resonances, but I did get a shape that match a bit better the graph from Timothy for the FF85WK
Was planing Saturday to buy some "wood" for the IEC baffle at a shop I found online but found out that it only open in weekdays... so I have to find a way to manage a visit but my work hours is identical tho them...
Also working a bit on the roof of a ruined house I have, it's my path to the calvary, it will probably still be a ruin at the end of my life.
Yeah dogs are like that, I had one when he wanted to bite he always aimed the testicles, could not leave it free a moment.
-yeah, this was the last one.
I'd probably get a cat (Blue Russian or Siamese) if it weren't that one of my family had allergies to cat hair.
I wanted another Border Collie (the only breed I've had good luck with), but ended-up with an Alaskan Husky - and knew (and said) it was a mistake (overall), but the rest of the family wanted him..
On the "plus" side the car that hit it must have been doing quite a bit more than the posted limit (30 mph) in our neighborhood: hit it HARD (brutal damage) and mercifully was most assuredly a quick death. It's also not the first time that's happened on the road next to us (about 14 years ago - same thing happened).
Oh well, back to working on the HT.. (..I'm thinking about adding a dipole subwoofer.)
Ho so he didn't survive, that's sad to hear.
The two dogs I had where German Shepherd and the two had a painful death, I don't think I'll have a dog again.
Dipole Subwoofer, didn't think that was even a thing, but I have read about isobaric though
The only subwoofer I ever did was a 12" closed and slanted, sounded great in my car, with the delay I really couldn't believe it was in my trunk.
I still have the driver (Infinity Perfect 12) but the suspensions and spider are sagging from years of storage
That seem to be like a big Luxurious home theater, movies and massages at the same time
I Read some more about REW and doing some more measurements, found out that nobody recommend to even try to run the it to get an accurate SPL level from driver, said it should be around 75db.
I tried using some cardboard to see if it made a difference and end up thinking that it's useless, lots of repeating patterns in the measurements probably due to resonances, but I did get a shape that match a bit better the graph from Timothy for the FF85WK
Was planing Saturday to buy some "wood" for the IEC baffle at a shop I found online but found out that it only open in weekdays... so I have to find a way to manage a visit but my work hours is identical tho them...
Also working a bit on the roof of a ruined house I have, it's my path to the calvary, it will probably still be a ruin at the end of my life.
The HT is only a 5-chair "affair" (2 in the front row and 3 in the back).. but the screen is about 8' by 13', and the front row will be about 9' away from the screen: sort of a mini "iMAX".
I still haven't gotten into fixing any of the other chairs yet..The dipole subwoofer would just be to "fill-in" some of that missing low-freq. "hall-sound" that the bass-shakers don't provide (and that I didn't account for originally). The overall design is quite unusual in that it was specifically designed so that there was very little sound-leakage into other parts of the house. Even small transmission-line subwoofer(s) that would typically be more practical for this situation, can wind-up pumping in really nauseating bass several rooms away (in effect generating another very long transmission line in the house). A dipole is also a *cheap solution if you get the right driver: weak motor (high Qe), large surface area and decent excursion, enough baffle and floor-loaded.
*..and I've been trying to spend as little as possible while still having a pretty-good result. (Got the power-recliners for $300 each on sale around Christmas.)
A cardboard setup should still have a wood connection point ("mini"-baffle) for the driver, and the cardboard should have tape (lossy) attached to that "mini-baffle. Of course the "mini-baffle" also needs chamfering at the rear for each driver (more so for the midrange than the midbass). You *might* be able to "get-away" with just using the driver and tape connection, but that's not something I've ever tried.
An entire home can be a daunting process even with subcontractors; I live in one and it's still far (cosmetically-interior) from finished.
(..I actually did the framing on that portion of the house (1100 sq feet 13'-high walls, not including its own 2-car garage) where the HT/Exercise-room/Craft-room is.)
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Wow that screen size seem quiet big compared to the distance, but you know when I am at the cinema (very rare) I always go in the last 10 rowsThe HT is only a 5-chair "affair" (2 in the front row and 3 in the back).. but the screen is about 8' by 13', and the front row will be about 9' away from the screen: sort of a mini "iMAX".
The dipole subwoofer would just be to "fill-in" some of that missing low-freq. "hall-sound" that the bass-shakers don't provide (and that I didn't account for originally). The overall design is quite unusual in that it was specifically designed so that there was very little sound-leakage into other parts of the house. Even small transmission-line subwoofer(s) that would typically be more practical for this situation, can wind-up pumping in really nauseating bass several rooms away (in effect generating another very long transmission line in the house). A dipole is also a *cheap solution if you get the right driver: weak motor (high Qe), large surface area and decent excursion, enough baffle and floor-loaded.
*..and I've been trying to spend as little as possible while still having a pretty-good result. (Got the power-recliners for $300 each on sale around Christmas.)
Yes in that case a sort of dipole make sense to me, less work than a transmission line cabinet, and you seem to have enough on your plate at the moment.
That sub bass travel really far indeed, it's the the only frequencies I get when a a young guy decide to share his taste of music driving slowly in the street...(notice how I am contained)
You must have nice movie night with the family in there, with popcorn that always fall in the tiniest crack of the seat
It's an excellent price for you power seats, a year ago I bought a Sofa 3 seats with two powered recliner and a longer seating, cost me an arm and a leg and I nearly never use it, only my ex did.
A cardboard setup should still have a wood connection point ("mini"-baffle) for the driver, and the cardboard should have tape (lossy) attached to that "mini-baffle. Of course the "mini-baffle" also needs chamfering at the rear for each driver (more so for the midrange than the midbass). You *might* be able to "get-away" with just using the driver and tape connection, but that's not something I've ever tried.
I have tried to keep as leaks to the front as limited as possible and placed them on a dense foam mat surrounded by that form egg-crate but I still feel like there is something amiss in the measurement, obviously I have repeating patterns that I attribute to the close surrounding, maybe the Mic Stand, Floor, cardboard not rigid enough, not sure I can get better with cardboard, here are the measurements, the green is the previous Fostex without cardboard, the two others are new.
[EDIT] Don't mind on the left when it is written 6.5LF I forgot to change the name to AXP-08)
[/QUOTE]An entire home can be a daunting process even with subcontractors; I live in one and it's still far (cosmetically-interior) from finished.
That's a lot of framing already, so is it a wood structure for the wall or only between floors ?
If it's only cosmetic it's not an a problem, well at least for me
I would be happy If this was what's remaining to do In mine
It is not that I am whining about it, but it's a series of bad choices that put me in the hole with that house, I assume but I completely underestimated the amount of work and overestimated the amount of will I had to rebuild that house with a full time job with nearly no help or support
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-it's wood framing 1x10 on "slab" (concrete), no second floor on that portion of the home. I'm to far south in the US for a basement.
(..keeping my fingers crossed) hoping you've figured-out the problems with the measurements.
I'm just about done with the chairs, though I ran into yet more problems that required additional modification to the bases I made for them. Just got the drivers for the dipole sub (waiting on the inductor for the eq./low-pass), and also got a sample pack of carpet tiles for the seating area (that will also be on a platform that conceals the subwoofer and adds-in two more bass-shakers for shaking the "floor"/carpet-platform). So my free-time is pretty much non-existent.
I've been taking some crappy pic.s as I go, at some point I might create a thread on it (and the troubles it's caused me).
(..keeping my fingers crossed) hoping you've figured-out the problems with the measurements.
I'm just about done with the chairs, though I ran into yet more problems that required additional modification to the bases I made for them. Just got the drivers for the dipole sub (waiting on the inductor for the eq./low-pass), and also got a sample pack of carpet tiles for the seating area (that will also be on a platform that conceals the subwoofer and adds-in two more bass-shakers for shaking the "floor"/carpet-platform). So my free-time is pretty much non-existent.
I've been taking some crappy pic.s as I go, at some point I might create a thread on it (and the troubles it's caused me).
In Belgium it is quiet rare to do wood framing for exterior walls, most construction are done with hollow bricks of concrete or clay, I suppose wood is more expensive here.
Fingers & Toes
I am not 100% sure yet about the measurements issue but I feel I may be onto something that does not feel right.
I have made a carboard box for the Fostex to test in a completely different setup (besides carboard resonant frequency) and the issue was the same.
But I can see that most of the peaks and dips I have are suspiciously at the exact opposite of the sound-card calibration curve (ragged black one) I can only show it on an individual measurement but it match many peaks and dips.
I have to investigate that further to see if that isn't just the compensation REW is doing to my measurement, and if the calibration is correct.
Even crappy It's good that you have pics anyway, because I have some difficulties picturing how you conceal a dipole sub with carpet
You know the saying that goes a bit like that: A picture is worth a thousand words
So the bass shakers are bolted to a wooden base that the seats are on ?
And the two additional In the floor at the feet of the seats ?
Out of curiosity what is the sub driver you chose ?
It's good to be busy, we need that to evade boredom. I wish you and your family to have great satisfaction once it's done, I'm sure it isn't just to watch Laurel & Hardy movies
Yup, looks like a calibration problem. I don't think that's a problem I ever personally encountered (..well, other than system audio levels changing).
(..it was 2x6 not 1x10 , and in certain load areas doubled-up side-by-side). Wood framing is common in the US unless you go past 3 stories. Interior>Sheet Rock (Gypsum panel)> 2x4 framing with fiberglass in-fill> foam panel> moisture barrier > Vinyl/Wood cladding or Brick. (..typical US new home construction.)
2 bass shakers attached via panels placed onto the frame of each chair, one for the back of the chair and one for the bottom of the chair (and the bottom panel has its own "legs" to somewhat isolate the chair from the floor).
There will be a two-level platform for all 5 chairs: 2 front chairs at floor level (raised about 1" off of the floor) and 3 rear chairs raised about 6-7" from the 2 front chairs. One bass shaker attached to the first row near-floor platform, and one attached to the raised rear platform. Subs hidden under the rear platform. Haven't started on any of that yet.
Cheap-@ss drivers for dipole use (that have a high Qe ..despite the datasheet's wildly-off number; scroll through user reviews):
https://www.newark.com/mcm-audio-select/55-2974/15-woofer-with-poly-conerubber/dp/80R7013
BTW, a proper dipole subwoofer would probably be 8 of these wired in series/parallel - but in my application they won't be at the average level, rather they are just for lower level low freq. effects to add that sense of space (.."hall sound") at an overall lower sp-level. Most of the bass response is derived from the bass-shakers and a bit of the high-pass roll-off from the other 7 system channels.
I don't think that's a problem I ever personally encountered (..well, other than system audio levels changing). (..it was 2x6 not 1x10
, and in certain load areas doubled-up side-by-side). Wood framing is common in the US unless you go past 3 stories. Interior>Sheet Rock (Gypsum panel)> 2x4 framing with fiberglass in-fill> foam panel> moisture barrier > Vinyl/Wood cladding or Brick. (..typical US new home construction.)2 bass shakers attached via panels placed onto the frame of each chair, one for the back of the chair and one for the bottom of the chair (and the bottom panel has its own "legs" to somewhat isolate the chair from the floor).
There will be a two-level platform for all 5 chairs: 2 front chairs at floor level (raised about 1" off of the floor) and 3 rear chairs raised about 6-7" from the 2 front chairs. One bass shaker attached to the first row near-floor platform, and one attached to the raised rear platform. Subs hidden under the rear platform. Haven't started on any of that yet.
Cheap-@ss drivers for dipole use (that have a high Qe ..despite the datasheet's wildly-off number; scroll through user reviews):
https://www.newark.com/mcm-audio-select/55-2974/15-woofer-with-poly-conerubber/dp/80R7013
BTW, a proper dipole subwoofer would probably be 8 of these wired in series/parallel - but in my application they won't be at the average level, rather they are just for lower level low freq. effects to add that sense of space (.."hall sound") at an overall lower sp-level. Most of the bass response is derived from the bass-shakers and a bit of the high-pass roll-off from the other 7 system channels.
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Yes you use an USB microphone if I remember well, easier to work with. I don't know what I was thinking when I decided to go for an XLR...
Besides the wood it's basically the same other materials here what kind of wood is used for the structure in general? autoclave douglas ?
With all that shaking on the seats you have to desolidarize the feet from the floor with silent-blocks or something or it's just bolted to in ?
Wow a 15" at that price, and 92db how is that even possible! I have seen the wall of text review, very nice of him to include all that information
8x15" yeah never in my life that will ever happen, I'm not that crazy (even if I had the space)
Besides the wood it's basically the same other materials here what kind of wood is used for the structure in general? autoclave douglas ?
With all that shaking on the seats you have to desolidarize the feet from the floor with silent-blocks or something or it's just bolted to in ?
Wow a 15" at that price, and 92db how is that even possible! I have seen the wall of text review, very nice of him to include all that information
8x15" yeah never in my life that will ever happen, I'm not that crazy (even if I had the space)
Nope, no USB mic.. A USB mic. is particularly useful in several respects, but NOT with respect to testing Harmonic Distortion (..which is something I became more interested in as time progressed). I probably will get one though, my spl-meter isn't great and that USB mic. UMIK-1 has a nice calibration file with sensitivity. That's still subject to the OS settings though.. Cross Spectrum sells a standard Dayton *EMM-6 with sensitivity that can be determined with their check values when putting in a certain spl from the soundcard-mic.out with a measured voltage-out from the mic.. (..but I still have a LOT of other projects to finish before then, including the computer build for that system - which will be based on virtual machines on-top of KVM-Qemu on a Linux machine run in system memory.)
*I've got 2 of these and one Behringer (..plus a mic. that came with Loudspeaker Lab that I purchase around 2001.) None are really good for close-mic measurements though (close to overload and adding a bit of distortion with non-linear testing), and all have high self-noise. I've not used any of this stuff in almost 5 years (including my DATS).
2x6 Pressure-treated Pine, with some real nasty chemicals in it. (..and the termites around here will still eat it.)
The isolation is actually more complicated than the feet alone (and I took pic.s of that), but these are the feet I use:
Everbilt 1 in. Black Rubber Leg Tips (4 per Pack)-49128 - The Home Depot
In particular the 1" diameter dowel-"legs" are just a bit shorter than the depth of those feet - this makes the primary connection point (between platform and feet) the top of the black rubber feet. Gives a real nice "cushioned" feel when you get in the chair as the rubber feet just slightly "buckle".
-yeah, I'm a real cheap b@stard! (..lol.) I've not taken them out of their boxes yet though, but I'm hoping they are ok. (..in fact, so far everything purchased for this has been good except for one of the mounting pieces for the screen.. oh, and one really cheap projector mount that wasn't worth the metal it was constructed of - spent 4-times as much on a new one that's excellent.)
BTW, the bass-shakers make a HUGE difference to the level of "involvement" of action sequences.
..I thought that I just finished up the chairs today, but after viewing part of Iron Man (for the umpteenth time), I've got one more chair to work on just a bit more.
*I've got 2 of these and one Behringer (..plus a mic. that came with Loudspeaker Lab that I purchase around 2001.) None are really good for close-mic measurements though (close to overload and adding a bit of distortion with non-linear testing), and all have high self-noise. I've not used any of this stuff in almost 5 years (including my DATS).
2x6 Pressure-treated Pine, with some real nasty chemicals in it. (..and the termites around here will still eat it.)
The isolation is actually more complicated than the feet alone (and I took pic.s of that), but these are the feet I use:
Everbilt 1 in. Black Rubber Leg Tips (4 per Pack)-49128 - The Home Depot
In particular the 1" diameter dowel-"legs" are just a bit shorter than the depth of those feet - this makes the primary connection point (between platform and feet) the top of the black rubber feet. Gives a real nice "cushioned" feel when you get in the chair as the rubber feet just slightly "buckle".
-yeah, I'm a real cheap b@stard! (..lol.) I've not taken them out of their boxes yet though, but I'm hoping they are ok. (..in fact, so far everything purchased for this has been good except for one of the mounting pieces for the screen.. oh, and one really cheap projector mount that wasn't worth the metal it was constructed of - spent 4-times as much on a new one that's excellent.)
BTW, the bass-shakers make a HUGE difference to the level of "involvement" of action sequences.
..I thought that I just finished up the chairs today, but after viewing part of Iron Man (for the umpteenth time), I've got one more chair to work on just a bit more.
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USB mics are also not recommended for producing measurement data for crossover simulation with VituixCAD or LspCAD or compatible without calculation of sound path length inside radiator and around box edges because timing difference between output (excitation) and input (measurement) signal does not stay constant so difference of phase responses to different off-axis angles and distances (~acoustic centers) is wrong by default.
Acoustic reference (radiator hanging on mic boom) is not convenient and support not usually available in measurement programs.
I've already been in contact with tech support of miniDSP that they should design "Umik-2"; with internal 2-channel sound card, internal loop back for timing reference and output connector(s). More motivating feedback might be needed because the first response was not promising. Focus is probably somewhere else than speaker engineering.
When I searched online to decide which microphone to buy I had seen that Cross Spectrum Labs but I rejected that option because of that added cost of delivery for an EMM6 premium plus ($137 total) and the difficulty of RMA from oversea. I also did think about just taking a cheap non calibrated mic but the cost difference wasn't that big and thought that would probably be the only one I will ever need
The main reason that I knew for not wanting an USB mic is that I didn't like to have that kind of fragile connector.
At my level I think the microphone I have will suffice
Any specific reason you want to use a VM for this besides having multiples OS's ?
Fortunately we don't have the termites here, we as human often eat chemically treated food, the termites just make do like us, leave them a stack of untreated woods around to make a diversion ?
So you have added other means of vibration isolation than the rubber feets ?
Cheap B@stard is a good trait to have when you don't have a unlimited stack of $
I think I have tried once a sort of bass shaker experience in an amusement park a long time ago, and I have the tramway that pass in the street that shake the apartment.
I would be love to watch Baraka or Samsara in a good HT with bass shakers and see if they are useful in that case.
Well, I think the calibration is ok now the curves look much more like I believe they should, it's still not very optimal because using a cardboard box (same size as the one planned) and the horizontal directivity are aproximated by eye.
I think it give me a good base to improve now, what does it look like to you Scott ?
[EDIT] Damn! I just noticed that I had Equalizer APO activated that whole time, ho well at least I noticed, will have to hone a bit my procedure
I think it give me a good base to improve now, what does it look like to you Scott ?
[EDIT] Damn! I just noticed that I had Equalizer APO activated that whole time, ho well at least I noticed, will have to hone a bit my procedure
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I knew about the phase problems as well.. and a lot of measurement software doesn't allow for actually measuring acoustic phase (..it's all derived).
(..my older Soundeasy didn't ..though I think it does now.) I'm one of those weirdos that likes near 1st order over 2 octaves (though you move the mic. much and the result changes), so I was (several years after 2000) looking for an acoustic phase solution that didn't cost huge amounts of money. Yeah, I don't think miniDSP cares about loudspeaker development that much. Of course it could just be a supply-chain thing for them: it's what they can get that will sell and make them a profit while adding some value to their line-up. The sensitivity measurement was one of those things they could add value to (..too bad the capsule isn't terribly stable over time depending on environment/conditions).
Who knows, in the next day or so they might get another pestering request!That is the correct without equalizer on
It still looks "off".
I was expecting something more linear (..like Tim's measurements).
Ironically the "dip" at 2.2-2.6 doesn't bother me that much, but rather that it doesn't "recover" to nearly the *same spl by 3.3 kHz. I'm also expecting that the response much below 900 Hz is less accurate, so I discount that result.
To give more context to how I view it: it looks like the target average usable spl is what you see at 3 kHz on this graph (more than -2db than what I was expecting).
IF it's correct, then we will have to look to more "robust" traditional tweeter solutions OR loose more efficiency.
*narrow band dips are often perceptually inconsequential (and can even be beneficial in some circumstances), but the result you have hear is to wide-band and will easily be audible unless eq.ed or designed with a different sort of accompanying tweeter.
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One of things I want is related to measuring loudspeakers.
I specifically want a few "fixed" (not updated) OS's with software.
1 VM (Windows): DATS (pass-through to that USB).
1 VM (Linux): REW (pass-through to another USB to another audio adapter).
1 VM (Windows): SoundEasy (pass-through to my PCI-based Echo Layla 3G), along with some other modeling software (probably VituixCAD)
. For the most part though it's SoundEasy for further development AFTER modeling - where you adjust crossover values digitally to get the right sound before finalizing the design and moving-onto crossover components."pass-through" in this instance means that only that particular VM "sees" the device it has assigned to it.
I've already got the hardware for this, it just a matter of remastering (the way I want it) a Linux VM server and then configuring each VM. Unfortunately I've not spent enough time, (even having started and stopped this multiple times within the past 2 years
), with this and I have *way* to many projects going right now. (..I've finished the chairs and now I've moved-onto "helping" my dad clean-out his garage for Father's Day.. and by "helping" I mean doing all the work.) Yes. Rubber feet > pegs > board > 1/4" isolation felt > shaker board attached to chair frame. (..though to be more correct above the shaker board is just about the opposite of that with bolts connecting the whole "sandwich" together.. but the bolts don't touch the shaker board: the holes for the shaker board are wider than the bolts that pass-through it to connect to the up-and-down "sandwich".)