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post #1051 of 1743 Old 02-24-2012, 07:15 PM
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cool man. there's a build thread for my sub here: http://forums.klipsch.com/forums/t/159382.aspx
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post #1052 of 1743 Old 02-24-2012, 07:49 PM
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I have done considerable research and it seems like that is the best driver for this enclosure right now.
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post #1053 of 1743 Old 02-24-2012, 08:00 PM
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Originally Posted by thaddeussmith View Post

cool man. there's a build thread for my sub here: http://forums.klipsch.com/forums/t/159382.aspx

I made it through your build thread last night. Excellent!


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Originally Posted by dutchswan0311 View Post

I have done considerable research and it seems like that is the best driver for this enclosure right now.

I'm sure that's what I'll end up going with. Especially after ordering the Bash500. I know I'll still have to worry about excursion but it should help with the thermal over the dvc model a little. The last thing I want to do is burn it up in the first few weeks. I get a little shall we say, greedy when I grab the volume knob.
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post #1054 of 1743 Old 02-24-2012, 10:16 PM - Thread Starter
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Quote:
Originally Posted by ovrrdrive View Post

Ok, I read all 35 pages of this thread to make sure I didn't ask something that was already covered. I have to say this is an amazing community for sure. Thanks lilmike for giving all of this away and everyone else that participated for giving all of the great advice. It's kind of funny that so many have already moved on and I'm just now finding out about this and considering building one. I bought the plans for the THT and after reading them and actually measuring my area there's no way I could fit a cab that wide up there. This one will fit with everything else and work out just great for me. My WAF isn't a problem as I'm already using Cerwin Vega E-715's for mains and this is only a foot or so taller than those are. It will be tight but will work just fine.

That said, lilmike what do you think about using a Titanic 15" and something like an inuke1000dsp to power it?

I only saw that driver mentioned in one other post but he was looking to narrow the cab and you said that driver was ok for his use but I was wondering about it's use in general for a standard size cab. Would there be any increased spl with the extra xmax and the higher wattage or are the gains so negligible that it isn't worth the extra expense?

I could go with the rf390 and a 300-500 watt bash plate just as easily but I was kind of hoping for something major with my first diy. If there aren't any reasons to go like that I will just build as suggested in the first post. The inuke 1000 gives up 300 watts x2 in 4ohm and supposedly 1000 bridged 4ohm mono. I'm sure the bridged rms is closer to 500 and by using the dsp I can save the $125 on a minidsp to use for the hp. Either way I'm sure it will crush the month old Klipsch RW12d I just got. It seems all it did was spark my curiosity in the hobby again and now I'm ready for something more substantial. I got it off the newegg $299 sale though so I'm sure I can unload it without a loss.

Hopefully I can start cutting wood next weekend... Thanks for everything so far and in advance for looking at this combo for me. If it's not worth it, what do you think the best combination is out there right now to use in this?

TIA.

You're welcome.

People move on, sure. Consider - we don't hear much from those that don't though. There will always be those that are looking for more, hope they find it some day, and more importantly, share the recipe with the rest of us.....

As far as the Titanic? It will work fine, probably no real benefit over the RSS390 though. Like dutch pointed out, the driver's behavior in the cabinet sets the power limit, not the driver. I would not be afraid to feed a Titanic 500 watts, more than that might be a stretch though. IMO, that is a pretty tiny spider for a driver with 20 mm xmax..... To be blunt, the DVC is nearly as capable, and is $100 cheaper. I'd run a DVC at 500 watts too, no worries at all.

Inuke 1K needs a fan mod, otherwise it should be a decent little amp, though the DSP does not go below 20 Hz, and a MiniDSP does. Think it is just a software thing - hope that Behringer addresses it someday. Nothing at all wrong with the Oaudio BASH amps.

Best driver??? I dunno. The MFW offered a considerable value while it was available, the 390HF and DVC offer similar performance, but the 390HF reportedly is cleaner, as it has a few refinements in the motor. Both cost more. I have never measured either though. Kicker's new single-coil 2-ohm Comp 15 works too, but at the current street price, I'd take a DVC over it in a heartbeat. The Titanic also works, and offers a little more stroke than the other options. Honestly - when you're looking at that much one-way cone throw(20 mm plus), its well past time to be planning for another cabinet.
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post #1055 of 1743 Old 02-24-2012, 10:18 PM - Thread Starter
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Originally Posted by thaddeussmith View Post

....

lilmike did very well on this one and it is most certainly a keeper.

Thanks. Glad you're enjoying it.
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post #1056 of 1743 Old 02-25-2012, 03:13 AM
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The F20 that I built with dual 10" drivers only needed about 80w to get the max output out of them, due to an xmax of 10mm. You may not need as much power as you think. It's quite easy to model in Hornresp, so that's what I suggest you do for any driver you are considering. Model it in half space and you can then compare the result to what you model in other programs.

F20 puts out nice clean punchy bass. With the drivers I'm using it's limited to about 25 Hz in theory, although with room gain perhaps not so much. I wouldn't use it up higher than say 60 Hz, the main limitation is bandwidth.
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post #1057 of 1743 Old 02-25-2012, 07:46 AM
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Thanks for all of the advice. I went ahead and ordered the RSS390HF and of course the Oaudio Bash 500 plate amp. Everything should start showing up towards the end of the week. Hopefully I'll be pissing off neighbors in a few weeks.
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post #1058 of 1743 Old 02-25-2012, 07:50 PM
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Personally, I'd rather get the DVC and 300w Bash amp and have very similar performance. I'd also be able to buy all the cabinet material and still be under what you'll spend on the RSS390 and 500w Bash amp. Maybe I'm just saying that because it's what I did but that's kinda what the F20 is all about, loud and clean bass at bargain prices.

On a side note, I found my wife playing hide and seek with the dogs...she was hiding inside the mouth of the F20.
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post #1059 of 1743 Old 02-25-2012, 09:01 PM
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Turn it up, let er rip and show the dog what a horn loaded woofer does! ... won't happen again
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post #1060 of 1743 Old 02-25-2012, 09:14 PM
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Quote:
Originally Posted by Danielson99 View Post

Personally, I'd rather get the DVC and 300w Bash amp and have very similar performance. I'd also be able to buy all the cabinet material and still be under what you'll spend on the RSS390 and 500w Bash amp. Maybe I'm just saying that because it's what I did but that's kinda what the F20 is all about, loud and clean bass at bargain prices.

On a side note, I found my wife playing hide and seek with the dogs...she was hiding inside the mouth of the F20.

I thought about that and realized that I wasn't necessarily upgrading this build with the higher end components but I figured I was giving myself a little future proofing with them too. I can always build something else down the road with them if I want to try something different and I figured the DVC and 300 watt combo wouldn't work as well in a different configuration. I started to build a dual 15" sealed cab before I stumbled on the F20 design and changed my mind to do this instead. If I decide to go that route in the future I'd only have to buy another RSS390.

If the F20 produces the way everyone says it will it's still quite a bargain.


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Turn it up, let er rip and show the dog what a horn loaded woofer does! ... won't happen again

I've been wracking my brain all night trying to figure out how his wife fit in the horn on the F20. The dog makes so much more sense!
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post #1061 of 1743 Old 02-25-2012, 09:24 PM
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Quote:
Originally Posted by ovrrdrive View Post

I thought about that and realized that I wasn't necessarily upgrading this build with the higher end components but I figured I was giving myself a little future proofing with them too. I can always build something else down the road with them if I want to try something different and I figured the DVC and 300 watt combo wouldn't work as well in a different configuration. I started to build a dual 15" sealed cab before I stumbled on the F20 design and changed my mind to do this instead. If I decide to go that route in the future I'd only have to buy another RSS390.

If the F20 produces the way everyone says it will it's still quite a bargain.




I've been wracking my brain all night trying to figure out how his wife fit in the horn on the F20. The dog makes so much more sense!

it was my wife, not my dogs

The mouth is 19"x15" and about 2'6" deep. Plenty of space for a 120lb woman. I've fit them into gym bags before...but that's another story.
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post #1062 of 1743 Old 02-26-2012, 08:51 AM
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This is the only modification that I can see will allow for a mouth on the side of the F20 that is of the same dimensions as the original. Does anyone see any issues with this design not working as well as the original design? Feedback is greatly appreciated! If anyone is able to model it, that would be even better (that is not a capability I have).
LL
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post #1063 of 1743 Old 02-26-2012, 10:52 AM - Thread Starter
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Quote:
Originally Posted by dutchswan0311 View Post
This is the only modification that I can see will allow for a mouth on the side of the F20 that is of the same dimensions as the original. Does anyone see any issues with this design not working as well as the original design? Feedback is greatly appreciated! If anyone is able to model it, that would be even better (that is not a capability I have).
Nope, do not do it that way.

Will post a sketchup of what I'd suggest as soon as I can.

And.....moments later.....



All of the updated Sketchup files are in the attached zip.

This will work, but it will be a bit different that what I made, as the horn path is shortened by a foot or so. I am not planning on building one to check it and see if it works OK, but changing the horn length by a foot in the model suggests that things will be fine.

 

Cinema F-20.zip 48.2529296875k . file
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post #1064 of 1743 Old 02-26-2012, 10:53 AM - Thread Starter
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Quote:
Originally Posted by Danielson99 View Post

it was my wife, not my dogs

The mouth is 19"x15" and about 2'6" deep. Plenty of space for a 120lb woman. I've fit them into gym bags before...but that's another story.

Epic!!!
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post #1065 of 1743 Old 02-26-2012, 02:43 PM
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Thanks Mike,

This makes for a nice option, and will likely be what I implement as I only have 26" behind my screen.

Larry
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post #1066 of 1743 Old 02-28-2012, 06:04 PM
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I havnt moved on . I'm still using two F20s and have two more built. I'm just waiting to complete my theater area (money issues). Of course I'm enhancing mine with a 21" infinite baffle maelstrom and a few 18"ers also in IB setup for below 20hz. I plan on going with DR200 speakers for LCR and having everything behind an AT screen
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post #1067 of 1743 Old 02-28-2012, 06:16 PM
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Originally Posted by blackoper View Post

I havnt moved on . I'm still using two F20s and have two more built. I'm just waiting to complete my theater area (money issues). Of course I'm enhancing mine with a 21" infinite baffle maelstrom and a few 18"ers also in IB setup for below 20hz. I plan on going with DR200 speakers for LCR and having everything behind an AT screen

Now THAT should be epic, with those covering your low end duty. The midbass output of these is undeniable. I hope you have good plans on how to integrate all these different types of drivers...?

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I'm using minidsp's to integrate. The IB subs only kick in at 20hz and lower as I didn't need any other sound areas filled in. The multiple f20s work great at everything else and are nice and flat after eq. I'll see how four do corner loaded when I get theater room completed
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post #1069 of 1743 Old 03-02-2012, 05:46 AM
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What do you guys think about using these to set the high and low pass settings for the F20? (or high/low passing things in general?)

http://www.parts-express.com/pe/show...number=266-252

http://www.parts-express.com/pe/show...number=266-246
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post #1070 of 1743 Old 03-02-2012, 05:54 AM
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The F20 will only need highpass if driven VERY HARD. 17-20Hz LR4 highpass should work well. I am not a fan of the FMODs for your application. Something like MiniDSP would be much better, and will have XLR outs for the pro amps you intend to drive.

JSS
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Originally Posted by maxmercy View Post

The F20 will only need highpass if driven VERY HARD. 17-20Hz LR4 highpass should work well. I am not a fan of the FMODs for your application. Something like MiniDSP would be much better, and will have XLR outs for the pro amps you intend to drive.

JSS

Thanks....I will take a look at the miniDSP.
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post #1072 of 1743 Old 03-02-2012, 08:17 AM
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Quote:
Originally Posted by Danielson99 View Post

it was my wife, not my dogs

The mouth is 19"x15" and about 2'6" deep. Plenty of space for a 120lb woman. I've fit them into gym bags before...but that's another story.

Awesome visual, and so true! It made me think of one of my friends from college. She and her twin sister like doing odd things at my house, and one of the funniest was getting inside this ugly hexagonal table I used to have.



One could easily fit in the mouth of an F-20, no doubt. Speaking of, those gals live in the SE corner of SD, a couple hours drive from central Iowa, and their family owns a vineyard. I see a lot in common with dutchswan, and I'm foreseeing a road trip to a dinner theater in our future.
LL
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post #1073 of 1743 Old 03-02-2012, 09:15 AM
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Awesome visual, and so true! It made me think of one of my friends from college. She and her twin sister like doing odd things at my house, and one of the funniest was getting inside this ugly hexagonal table I used to have.

One could easily fit in the mouth of an F-20, no doubt. Speaking of, those gals live in the SE corner of SD, a couple hours drive from central Iowa, and their family owns a vineyard. I see a lot in common with dutchswan, and I'm foreseeing a road trip to a dinner theater in our future.

My grandma had the same table!!!

I think I somehow ended up with it in my house.

Matt

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I'm trying to imagine just how much larger that table would need to be for me to fit inside of it. Let's just say I'd need several more sheets of plywood. 5x5 if available.

Btw, I start cutting wood in the morning for the F20.
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Quote:
Originally Posted by blackoper View Post

I havnt moved on . I'm still using two F20s and have two more built. I'm just waiting to complete my theater area (money issues). Of course I'm enhancing mine with a 21" infinite baffle maelstrom and a few 18"ers also in IB setup for below 20hz. I plan on going with DR200 speakers for LCR and having everything behind an AT screen

Just remember in my room my AVR set the crossover of the DR-200's to 150hz and I don't know how smooth the response is on the F-20 for those frequencies. I never used a HP filter with mine because I could get 110 dB's at 10hz with them and that was enough with any movie. Of course I used 4 of them so with one or 2 I would high pass them or don't run them at reference. For very high output from 20hz and above these are the clear winner for bang for buck!

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I never used a HP filter with mine because I could get 110 dB's at 10hz

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post #1077 of 1743 Old 03-02-2012, 07:41 PM
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@lilmike

I decided to fork over the money and build the rest of the F20s out of 5' x 5' Baltic Birch. I was happy to see that you had a cut schematic for plywood of those dimensions. After I made a few cuts, I remembered that this BB is 18mm, which is 11/16; a full 1/16 less in thickness than the 3/4" plywood the instructions call for. I immediately started doing math to see if your 5x5 cut sheet has accounted for this difference in thickness. It appears you did attempt to account for it, but if my math is correct, your measurements are not. Below I have put together some numbers:

Panel 6 should be 1/16" longer than the 44 3/8 the 3/4" ply calls for. This would be 44 7/16. You have this listed as 44 3/4, which my math says is a full 5/16" too long. Can you advise?

Panel 10 should be 1/8" longer than the 58 1/2 the 3/4" ply calls for. This would be 58 5/8". You have this listed as 58 3/4, which my math says is a full 1/8" too long. Can you advise?

Panel 4 should be 1/16" longer to account for the fact that Panel 6 is less that thickness, assuming panel 9's less thickness is oriented to the chamber (making the chamber 1/6" bigger on that side). This one is probably nitpicking, since the corners of panels 4 & 9 probably don't need to match up perfectly, as the interior space is unaffected by the 1/16" difference.

Panel 5 should be either 1/16" longer (if panels 3 & 9 split the difference of the 1/8" gap they create together). If panels 3 & 9 are put to the outer boundaries of their 3/4" counterparts, then it would be 1/8" longer. My math says that the instructions are basically correct.

I am mostly concerned about having gaps and my sub not being sealed. Since I have already cut into my BB sheets, I will finish this sub with that wood. My last two F20s I will just use normal 7ply 3/4" birch to make my life easier. :-|

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post #1078 of 1743 Old 03-03-2012, 10:45 AM - Thread Starter
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Quote:
Originally Posted by dutchswan0311 View Post

@lilmike

I decided to fork over the money and build the rest of the F20s out of 5' x 5' Baltic Birch. I was happy to see that you had a cut schematic for plywood of those dimensions. After I made a few cuts, I remembered that this BB is 18mm, which is 11/16; a full 1/16 less in thickness than the 3/4" plywood the instructions call for. I immediately started doing math to see if your 5x5 cut sheet has accounted for this difference in thickness. It appears you did attempt to account for it, but if my math is correct, your measurements are not. Below I have put together some numbers:

Panel 6 should be 1/16" longer than the 44 3/8 the 3/4" ply calls for. This would be 44 7/16. You have this listed as 44 3/4, which my math says is a full 5/16" too long. Can you advise?

Panel 10 should be 1/8" longer than the 58 1/2 the 3/4" ply calls for. This would be 58 5/8". You have this listed as 58 3/4, which my math says is a full 1/8" too long. Can you advise?

Panel 4 should be 1/16" longer to account for the fact that Panel 6 is less that thickness, assuming panel 9's less thickness is oriented to the chamber (making the chamber 1/6" bigger on that side). This one is probably nitpicking, since the corners of panels 4 & 9 probably don't need to match up perfectly, as the interior space is unaffected by the 1/16" difference.

Panel 5 should be either 1/16" longer (if panels 3 & 9 split the difference of the 1/8" gap they create together). If panels 3 & 9 are put to the outer boundaries of their 3/4" counterparts, then it would be 1/8" longer. My math says that the instructions are basically correct.

I am mostly concerned about having gaps and my sub not being sealed. Since I have already cut into my BB sheets, I will finish this sub with that wood. My last two F20s I will just use normal 7ply 3/4" birch to make my life easier. :-|


Normal 3/4 ply isn't 3/4 either...

You can certainly do things that way, or, you can keep the internal path the same, lose the extra mm or two on the outside.

Either approach works, you're talking an 1/8" in 5 feet, when dealing with wavelengths that are closer to 50 feet. As long at things are sealed, it will work fine.
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post #1079 of 1743 Old 03-03-2012, 02:11 PM
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My issues with the 1/8" were that it, in addition to the 36mm of wood that the top and bottom panels make up, made the top stick up 1/8" higher than the side panels. That just sounds like a lot of sanding. I am sure it would sound the same, but aesthetically it makes sense to cut it so everything is flush. Not saying anything against you Mike; this is one of the best threads out there. I just found things easier with the 3/4 " x 8 x 4 stuff.
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post #1080 of 1743 Old 03-03-2012, 02:48 PM
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Originally Posted by dutchswan0311 View Post

My issues with the 1/8" were that it, in addition to the 36mm of wood that the top and bottom panels make up, made the top stick up 1/8" higher than the side panels. That just sounds like a lot of sanding. I am sure it would sound the same, but aesthetically it makes sense to cut it so everything is flush. Not saying anything against you Mike; this is one of the best threads out there. I just found things easier with the 3/4 " x 8 x 4 stuff.

Flush trim bit......
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