12" JBL speaker $29 on black friday at Bestbuy - Page 73 - AVS Forum | Home Theater Discussions And Reviews
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post #2161 of 2328 Old 06-07-2019, 08:49 AM
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I was able to figure out the what, just not the how/why.

Did you really need to quote that entire post in your reply?
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post #2162 of 2328 Old 06-07-2019, 12:05 PM
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Quote:
Originally Posted by DaleNixon View Post
&#115 = s

...and it all makes sense.
Hahaha. Yes it does. I don't know why I didn't see that before. I wonder why the 's' got munged.

Back on topic, I've decided I want more of these JBLs. I want to do 18 of them nearfield. Just waiting on Bestbuy to give me the good word....
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post #2163 of 2328 Old 06-07-2019, 12:35 PM
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It's been $65 there for a (relatively) long time, as a "sale" price. We may not see $30 again.
Two left here:
https://www.caraudioco.com/products/...4&currency=USD
Otherwise $50 at Sonic.
Michael

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post #2164 of 2328 Old 06-07-2019, 02:13 PM
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Quote:
Originally Posted by LastButNotLeast View Post
It's been $65 there for a (relatively) long time, as a "sale" price. We may not see $30 again.
Two left here:
https://www.caraudioco.com/products/...4&currency=USD
Otherwise $50 at Sonic.
Michael
Thanks Michael!

Looks like they only have 2 left at caraudioco.

Walmart has the CS1214 for $49.95
Walmart CS1214

I'm not ready to make sawdust yet so I'll take the risk (of the price going up) and wait them out.
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post #2165 of 2328 Old 06-07-2019, 05:04 PM
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I think I’m going to get 8 more (for 24 total ) during the next sale.

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post #2166 of 2328 Old 06-08-2019, 09:37 AM
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I'm about 1/2 way through reading this thread now and its been very informative. I was trying to avoid asking any more questions until I made it all the way through, but figured -- why not ask as I'm chugging along.

So, I got my MDF from Home Depot and it got cut wrong, but it actually works out because I prefer the redesign it forced me to do. Based on the attached image, would you recommend having bracing? I read somewhere that you should for anything 12"+, but I was thinking maybe I can get away without it.

I'll likely be going with a 3000DSP for 8 total speakers, if this factors in. By the way, I read someone estimated spending about $200 for a 3000DSP, but I haven't had any luck finding anything in that ballpark (closer to the $300 range). What's the strategy for getting the best price on these?

I'm in a part of the the thread where REW is being discussed and I have what is likely a dumb question. Can a calibration mic that comes with a receiver be used to setup subs? I guessing not perfectly, but could it be used to tweak and compare settings changes?

@trilkb , I'm thinking of following your lead and use binding posts for connections. I saw the way you connected the wiring externally, but was wondering how you connected internally to the sub.
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post #2167 of 2328 Old 06-08-2019, 03:56 PM
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You mean more bracing than the diagram already shows, or the brace that's in the diagram? If it were me, I WOULD put the brace that's in the diagram in, I would not likely add more than that.

Chris
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post #2168 of 2328 Old 06-08-2019, 04:41 PM
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Quote:
Originally Posted by rocCity View Post
I'm about 1/2 way through reading this thread now and its been very informative. I was trying to avoid asking any more questions until I made it all the way through, but figured -- why not ask as I'm chugging along.

So, I got my MDF from Home Depot and it got cut wrong, but it actually works out because I prefer the redesign it forced me to do. Based on the attached image, would you recommend having bracing? I read somewhere that you should for anything 12"+, but I was thinking maybe I can get away without it.

I'll likely be going with a 3000DSP for 8 total speakers, if this factors in. By the way, I read someone estimated spending about $200 for a 3000DSP, but I haven't had any luck finding anything in that ballpark (closer to the $300 range). What's the strategy for getting the best price on these?

I'm in a part of the the thread where REW is being discussed and I have what is likely a dumb question. Can a calibration mic that comes with a receiver be used to setup subs? I guessing not perfectly, but could it be used to tweak and compare settings changes?

@trilkb , I'm thinking of following your lead and use binding posts for connections. I saw the way you connected the wiring externally, but was wondering how you connected internally to the sub.
Well, it's probably fine, but I'd put something side-to-side and top-to-bottom. For the back, I'd probably glue a piece against the back running top-to-bottom or side-to-side. Could be overkill, but it doesn't cost anything.

I think I've read about someone using their calibration AVR's mic but it's analog and you'd need to go through a USB audio interface, and, it's not calibrated. The USB UMIK mics are really a good deal for $100 (and they are calibrated).

Nothing magic about finding a 3000 on the cheap. I've stuck to the 6000's since starting the DIY thing (I have two 6000D's) so I haven't paid much attention to the prices of the 3000's. Just keep checking the 'bay and the retailers.

PS> Window bracing in the middle would cover the side-to-side and top-to-bottom.
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post #2169 of 2328 Old 06-10-2019, 08:08 AM
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Quote:
Originally Posted by rocCity View Post
I'm about 1/2 way through reading this thread now and its been very informative. I was trying to avoid asking any more questions until I made it all the way through, but figured -- why not ask as I'm chugging along.

So, I got my MDF from Home Depot and it got cut wrong, but it actually works out because I prefer the redesign it forced me to do. Based on the attached image, would you recommend having bracing? I read somewhere that you should for anything 12"+, but I was thinking maybe I can get away without it.

I'll likely be going with a 3000DSP for 8 total speakers, if this factors in. By the way, I read someone estimated spending about $200 for a 3000DSP, but I haven't had any luck finding anything in that ballpark (closer to the $300 range). What's the strategy for getting the best price on these?

I'm in a part of the the thread where REW is being discussed and I have what is likely a dumb question. Can a calibration mic that comes with a receiver be used to setup subs? I guessing not perfectly, but could it be used to tweak and compare settings changes?

@trilkb , I'm thinking of following your lead and use binding posts for connections. I saw the way you connected the wiring externally, but was wondering how you connected internally to the sub.
I just drilled a 1/4 hole to go to the other side of the cabinet to wire them in series.

- 6 BA CR6 array center channel, QSC AD-S82 L/R, 4 jbl 8330a surr , 8 jbl 12" subs w/Inuke 6000. JVC rs420, Denon x4000, Sony x800 -
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post #2170 of 2328 Old 06-10-2019, 03:59 PM
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I think I’m going to get 8 more (for 24 total ) during the next sale.



Any idea when the next sale will be? Please let me know when they are on sale again. I might jump on this wagon.
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post #2171 of 2328 Old 06-10-2019, 06:16 PM
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Hey guys, I've been slowly coming to terms with the project and balancing a very busy work life (odd shifts too, don't get me started on my lack of sleep health) and hit up a couple car audio sub box makers for some quotes. It's too early to tell what's what, but I asked for:

-3/4" mdf
-double thick front panel for flush mounting
-quad holes
-minimal bracing
-no terminals
-no carpet
-dimensions I came up with for my purposes are 57.5" x 16" x 20", which gives a little under 2 cuft per JBL after braces and driver displacement.

Quotes have been all over the place. As ridiculous as $1400 for 4 of them, as low as $80 each. I'll keep you guys posted.
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post #2172 of 2328 Old 06-10-2019, 07:07 PM
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I'm sure you've seen the big brother to the ones I used:
https://www.ebay.com/itm/HD12-4HOLE-...7eb511bd8f8682
Michael
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post #2173 of 2328 Old 06-10-2019, 07:58 PM
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Yes, and while I like how it looks, objectively I don't like 'er so much. The construction is okay, but the specs are a lie. 1.6 cuft is external dimension volume per sub. Internal is 1.25 or so, which IMO is not enough to eq the snot out of these best. My computer setup uses that same box, it's "ok" as it's still 4 12's in a nearfield setup but I'm not impressed. An extra half a cubic foot makes a significant difference. Bummer since it's cheap and already available.

Chris
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post #2174 of 2328 Old 06-11-2019, 01:19 AM
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Here is a screenshot of the first 4 JBL on the left side wall in front of the MLP. Will get the other 4 (right wall) setup this week. I am so fascinated by them that I consider selling my Klipsch Ultra KW120 subwoofers and get 4 more JBL under the screen. Will then have 12 JBLs. :-)
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post #2175 of 2328 Old 06-11-2019, 04:34 AM
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Quote:
Originally Posted by Nima View Post
Here is a screenshot of the first 4 JBL on the left side wall in front of the MLP. Will get the other 4 (right wall) setup this week. I am so fascinated by them that I consider selling my Klipsch Ultra KW120 subwoofers and get 4 more JBL under the screen. Will then have 12 JBLs. :-)
What kind of EQ do you use with them to get that? Those are digging pretty deep.
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post #2176 of 2328 Old 06-11-2019, 05:29 AM
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I just reduced the higher frequencies around 40 and 70hz which were also heavily exaggerated by room modes and put a LS of 10db at around 20Hz.

I used REW AutoEQ, lowered the target setting to 85 and put in the LS manually.

My room is fully treated with bass traps and accoustic panels.
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post #2177 of 2328 Old 06-11-2019, 07:56 AM
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Quote:
Originally Posted by Chris Popovich View Post
Yes, and while I like how it looks, objectively I don't like 'er so much. The construction is okay, but the specs are a lie. 1.6 cuft is external dimension volume per sub. Internal is 1.25 or so, which IMO is not enough to eq the snot out of these best. My computer setup uses that same box, it's "ok" as it's still 4 12's in a nearfield setup but I'm not impressed. An extra half a cubic foot makes a significant difference. Bummer since it's cheap and already available.

Chris
That's disappointing. I didn't do the math on the dimensions to confirm it, but when they list "airspace" on the specs, it certainly implies that they are giving the internal dimensions. The internal after doing the math (before the sub is added to reduce it) is just over 1.3 cubic feet if I did my math correctly. What will an extra half cubic foot bring to the table?

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post #2178 of 2328 Old 06-11-2019, 10:44 AM
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Originally Posted by Chris Popovich View Post
An extra half a cubic foot makes a significant difference.
How about adding a couple of these?
https://www.amazon.com/Pipemans-Inst...gateway&sr=8-5

Michael
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post #2179 of 2328 Old 06-11-2019, 10:50 AM
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Quote:
Originally Posted by LastButNotLeast View Post
How about adding a couple of these?
https://www.amazon.com/Pipemans-Inst...gateway&sr=8-5

Michael
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post #2180 of 2328 Old 06-11-2019, 02:26 PM
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Quote:
Originally Posted by Chris Popovich View Post
Yes, and while I like how it looks, objectively I don't like 'er so much. The construction is okay, but the specs are a lie. 1.6 cuft is external dimension volume per sub. Internal is 1.25 or so, which IMO is not enough to eq the snot out of these best. My computer setup uses that same box, it's "ok" as it's still 4 12's in a nearfield setup but I'm not impressed. An extra half a cubic foot makes a significant difference. Bummer since it's cheap and already available.

Chris
This is interesting to hear because the winisd modeling just doesn't show this... Going by modeling, 2cu is under 1db higher than 1.25cu
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post #2181 of 2328 Old 06-11-2019, 03:55 PM
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Holy shit, my eyes hurt.

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post #2182 of 2328 Old 06-11-2019, 06:10 PM
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Quote:
Originally Posted by Nima View Post
Here is a screenshot of the first 4 JBL on the left side wall in front of the MLP. Will get the other 4 (right wall) setup this week. I am so fascinated by them that I consider selling my Klipsch Ultra KW120 subwoofers and get 4 more JBL under the screen. Will then have 12 JBLs. :-)
WOW! kw120 is $3k?! Sell that biotch, or biotch's!

12 subs give you more coverage over all of your seats anyways. Pretty awesome that you think 4 gives it a run, I have 8 and am super happy with them.
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post #2183 of 2328 Old 06-11-2019, 06:25 PM
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Holy shit, my eyes hurt.
They're still working on it:
https://www.avsforum.com/forum/43-fo...l#post58168828
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post #2184 of 2328 Old 06-11-2019, 06:46 PM
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Guys the sims are sims. Do not take them to the bank until you've run the real thing in real space.

Sim wise it's not a huge deal, but remember these are budget drivers. What I have personally observed is that my 4 sealed/stuffed 1.25 cuft JBL's used for my computer system distort on loud low frequencies FAR earlier on the SPL spectrum than the same in ~1.6 cuft enclosures. Let's think about it; smaller box, more boost, more power, more heat, more air non-linearities, more reliance on the cheap motor..... anyone surprised at more distortion? To me that's expected when you spend some time thinking about it.

If you have enough of them I don't think it matters, but I don't like these drivers as much in 1.25 cuft as I do in 1.5cuft+, and they probably stop being worth their space (IMO) above 2 cuft unless you just have mountains of available volume.

Note that I DO use a subharmonic synth, and that adds significantly to the 15-35hz content, so this is going to be more obvious to me than you guys (most likely).
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I'm disappointed in myself for not doing the calculations to figure out, before I purchased and used them, that the QPOWER HD 12 four hole boxes are smaller than advertised. I just assumed 1.6 cubic feet of "airspace" meant the interior measurement. My incorrect assumption about the size is why I picked them. In any event, I've been kicking around in my head some ideas to add more cubic feet.

First, I thought about building up the front of the box. However, I'd have to add four inches to the front to get each enclosure up to 1.6 cubic feet. That seems like more trouble than just starting over and building new boxes from scratch.

Second, in theory, I could modify these four box enclosures into two box enclosures. I could cut out two of the braces on the inside, creating two enclosures that are twice as large instead of four small ones. Then I could attach a new face board over the top of the existing front of the cabinet to seal off two of the round holes. That would give me 2.6 cubic feet per box, which may be too much (is it?), but I could add some of my scrap 2x4s as extra bracing to shrink it down to 2.0 or less. In addition to the work making modifications, another downside is that I'd be kicking half of my subs out of their new homes, so I'd have to buy more cabinets and modify them too.

We promptly went on vacation when I finished the project, so I really don't know how well they're going to work "as is." I'll play around with them for a while before deciding whether to change anything. Still, it's annoying me that I bought smaller sub boxes than I had intended.
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post #2186 of 2328 Old 06-11-2019, 07:54 PM
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Thanx. I purposely typed out the symbols s instead of typing the letter s because I didn't actually want to curse on the forum. Just make a joke that the post above mine was painful to look at. When I got e-mail notification of you quoting me, the symbols were replaced with the letter s. Oh well, hope my suspension isn't too long.

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post #2187 of 2328 Old 06-11-2019, 08:00 PM
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Actually, that info may help with the diagnosis. I'd suggest adding it to the thread linked above.
Michael

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post #2188 of 2328 Old 06-11-2019, 10:11 PM
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Quote:
Originally Posted by Blue View Post
I'm disappointed in myself for not doing the calculations to figure out, before I purchased and used them, that the QPOWER HD 12 four hole boxes are smaller than advertised. I just assumed 1.6 cubic feet of "airspace" meant the interior measurement. My incorrect assumption about the size is why I picked them. In any event, I've been kicking around in my head some ideas to add more cubic feet.

First, I thought about building up the front of the box. However, I'd have to add four inches to the front to get each enclosure up to 1.6 cubic feet. That seems like more trouble than just starting over and building new boxes from scratch.

Second, in theory, I could modify these four box enclosures into two box enclosures. I could cut out two of the braces on the inside, creating two enclosures that are twice as large instead of four small ones. Then I could attach a new face board over the top of the existing front of the cabinet to seal off two of the round holes. That would give me 2.6 cubic feet per box, which may be too much (is it?), but I could add some of my scrap 2x4s as extra bracing to shrink it down to 2.0 or less. In addition to the work making modifications, another downside is that I'd be kicking half of my subs out of their new homes, so I'd have to buy more cabinets and modify them too.

We promptly went on vacation when I finished the project, so I really don't know how well they're going to work "as is." I'll play around with them for a while before deciding whether to change anything. Still, it's annoying me that I bought smaller sub boxes than I had intended.

It is irritating. Lesson learned for me too. Definitely try them out before you worry too much. You have a bunch, if I recall correctly. If they play loud, low, and clean enough.... why bother with a change? My situation is a little different, and on the computer system I *only* have 4 of them so it's not that hard for me to max them out using the other subharmonic synth with the 15hz high pass. Understand this can add 15dB to power requirements, easily, which is another world full of low frequency info. For the main system, this is why I'm making my boxes bigger.

Let's say you're not happy with them though. You have choices. I'd probably just add another glob or two of JBL's and not worry. I probably wouldn't give them 2.5 cuft each, nothing wrong with that but that space adds up quick. If you do go that route, I wouldn't decrease internal volume, worst case you'll need to add a high pass, but that's no big deal.


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post #2189 of 2328 Old 06-12-2019, 03:11 AM
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I got my second array setup and spent a lot of time moving the 4 dual JBL boxes around at the sidewalls. I even went so far and stacked 2 boxes (4 JBL) on top of each other.

In the end I choose the configuration in which all of the 8 JBL reacted the best to Global EQ. I created a EQ list using REW and AutoEQ and imported it into Input 1 on the 2x4HD.


After that I loaded up Dirac and let it correct this EQ response. I will post pictures shortly.

Dirac on its own was not able to correct the JBLs as I would have liked, I think since they require a more brute force approach (but they take a beating).
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post #2190 of 2328 Old 06-12-2019, 03:26 AM
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Pictures:

1. 8 JBL (4 on each side wall in front of MLP) RAW

2. AutoEQ und Boost into MiniDSP

3. After Dirac
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Last edited by Nima; 06-12-2019 at 03:39 AM.
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