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post #61 of 158 Old 05-04-2014, 11:51 PM - Thread Starter
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Quote:
Originally Posted by Petden View Post

I would say port velocity is a little high the reason I say this is because the um 18 can reach out probably close to 30mm of excursion and handle quite a bit more power. As you start adding more power that port velocity will most likely be in the 20's and has the potential to be audible.

This is not an UM18-22 driver. As I wrote Xmax=22mm and I'm using it all. smile.gif
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post #62 of 158 Old 05-05-2014, 12:21 AM
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Is it the 18ho. I think it was measured usable out to 22mm.
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post #63 of 158 Old 05-05-2014, 01:20 AM - Thread Starter
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It's not an 18" driver. But good try though smile.gif
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post #64 of 158 Old 05-05-2014, 07:27 AM
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Is it the original Scan Speak driver you wanted to use? That would be funny :) 

 

It seriously doesn't need a HP? I've never seen a ported sub not need a high pass. I guess it is tuned really low though. Cool stuff. That looks great.

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post #65 of 158 Old 05-05-2014, 07:56 AM - Thread Starter
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Originally Posted by TheGiantPeach View Post

Is it the original Scan Speak driver you wanted to use? That would be funny smile.gif 

It seriously doesn't need a HP? I've never seen a ported sub not need a high pass. I guess it is tuned really low though. Cool stuff. That looks great.

Nope. It's the RE Audio MX12 D1. Look for yourself. It's possible I've missed something...

REAudioMX12vented.zip 1k .zip file

One major obstacle is the port. Where the hell am I going to find a tube with exactly 140mm diameter and 1082.4mm length? I'm also afraid is a little to long...

If it was not for the port(s) I would go for a vented box all day long because it goes lower and the SPL is about the same but I hesitate.
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post #66 of 158 Old 05-05-2014, 11:00 AM
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Quote:
Originally Posted by cochinada View Post

Nope. It's the RE Audio MX12 D1. Look for yourself. It's possible I've missed something...

REAudioMX12vented.zip 1k .zip file

One major obstacle is the port. Where the hell am I going to find a tube with exactly 140mm diameter and 1082.4mm length? I'm also afraid is a little to long...

If it was not for the port(s) I would go for a vented box all day long because it goes lower and the SPL is about the same but I hesitate.
If it isn't 140mm, you adjust the length to get the proper Fb. As for length, get it too long and cut to length.
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post #67 of 158 Old 05-05-2014, 12:24 PM
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Quote:
Originally Posted by cochinada View Post


Nope. It's the RE Audio MX12 D1. Look for yourself. It's possible I've missed something...

REAudioMX12vented.zip 1k .zip file

One major obstacle is the port. Where the hell am I going to find a tube with exactly 140mm diameter and 1082.4mm length? I'm also afraid is a little to long...

If it was not for the port(s) I would go for a vented box all day long because it goes lower and the SPL is about the same but I hesitate.

 

It's true that you don't NEED a HP, but you might as well add one at 8hz. It will lower the excursion down around 10hz and let you give it more power. See?

 

It does pretty much nothing to the overall frequency response, and it gives you another 2 or so dB of output.

 

As far as ports go, if I were you I would do a slot port, since you're tuning so low and the port will have to be long. You can do 90 degree bends in slot ports much easier than with round ports. For my sub, I did dual 4 inch round ports with flares on both ends and it was a huge pain to do the 90 degree bends. I'll probably do slots from now on even though they aren't as sexy as having flared ports on your baffle :)

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post #68 of 158 Old 05-05-2014, 02:15 PM - Thread Starter
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Quote:
Originally Posted by TheGiantPeach View Post

It's true that you don't NEED a HP, but you might as well add one at 8hz. It will lower the excursion down around 10hz and let you give it more power. See?





It does pretty much nothing to the overall frequency response, and it gives you another 2 or so dB of output.

As far as ports go, if I were you I would do a slot port, since you're tuning so low and the port will have to be long. You can do 90 degree bends in slot ports much easier than with round ports. For my sub, I did dual 4 inch round ports with flares on both ends and it was a huge pain to do the 90 degree bends. I'll probably do slots from now on even though they aren't as sexy as having flared ports on your baffle smile.gif

Nice suggestion! But +2dB is a little optimistic though because more than 120W and the air velocity rises above 19m/s. 120'W was the most I could apply with a HP Butterworth 2nd order at 8Hz.
About the slot ports, don't forget I'm building a cylinder so there are no straight sides to serve as a guide. My cylinder will have about 1600mm high so there is no need to bend the port at least.
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Originally Posted by rlj5242 View Post

If it isn't 140mm, you adjust the length to get the proper Fb. As for length, get it too long and cut to length.

Assuming I can calculate the new port using some tool (flareit ?) what about the new air speed? To be on the safe side it's best to increase the diameter rather than reduce it or is it?
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post #69 of 158 Old 05-05-2014, 02:34 PM
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Quote:
Originally Posted by cochinada View Post

Assuming I can calculate the new port using some tool (flareit ?) what about the new air speed? To be on the safe side it's best to increase the diameter rather than reduce it or is it?
I use PSP's tool http://www.psp-inc.com/tools.html

If you go with a larger diameter, you will not have an air speed issue.
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post #70 of 158 Old 05-05-2014, 03:56 PM
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Originally Posted by cochinada View Post


Nice suggestion! But +2dB is a little optimistic though because more than 120W and the air velocity rises above 19m/s. 120'W was the most I could apply with a HP Butterworth 2nd order at 8Hz.
About the slot ports, don't forget I'm building a cylinder so there are no straight sides to serve as a guide. My cylinder will have about 1600mm high so there is no need to bend the port at least.
Assuming I can calculate the new port using some tool (flareit ?) what about the new air speed? To be on the safe side it's best to increase the diameter rather than reduce it or is it?

Oh right cylinder subs! Sorry I forgot. 

 

You can just change the port diameter right there in winISD and it will adjust your air velocity to reflect your changes.

 

Also, if you're considering minidsp, you can do up to an 8th order BW, which gives you a steeper filter and doesn't affect the frequencies above it as much. Dont know if you're thinking about minidsp, but if you are, a steeper filter makes a big difference.

 

I don't know what common sizes of pvc they have there but 6 inches (153mm) looks really good. It would be 1292mm long and you could push 150 watts before hitting 19m/s (assuming a HP).

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post #71 of 158 Old 05-05-2014, 11:53 PM - Thread Starter
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Originally Posted by TheGiantPeach View Post

You can just change the port diameter right there in winISD and it will adjust your air velocity to reflect your changes.

Indeed! I never thought this field was editable.

Quote:
Originally Posted by TheGiantPeach View Post

Also, if you're considering minidsp, you can do up to an 8th order BW, which gives you a steeper filter and doesn't affect the frequencies above it as much. Dont know if you're thinking about minidsp, but if you are, a steeper filter makes a big difference.

I'm thinking that if I go for a vented box I won't be needing an LT so, if with the iNuke3000DSP it's possible to define let's say 3 or more EQ filters together with a HP with enough accuracy as allowing 1Hz and 0.5dB steps and even better decimal changes in Q, I guess I can save a hundred Euro and skip the miniDSP. I believe you have an iNuke right? Can you tell me if these things are all possible?

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I don't know what common sizes of pvc they have there but 6 inches (153mm) looks really good. It would be 1292mm long and you could push 150 watts before hitting 19m/s (assuming a HP).

Well me neither as I never purchased one but I reckon that it's not going to be easy to find one longer than 1292mm.
I could push 140W maximum as more than that and the cone excursion at 10Hz goes beyond 22mm. With a HP (Butterwoth, n=2, fc=8,00Hz).

But there is another trade-off as the 1st port resonance lowers dangerously from 158.75Hz to 132.95Hz. eek.gif
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post #72 of 158 Old 05-06-2014, 02:31 AM - Thread Starter
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This one from Parts-Express is the right diameter but this observation ruins everything: "Create a port up to 17" long".
How come 17" is the limit? Why? Mine needs to have more than 50" long!!! eek.gif
How am I gonna do this?

Now I see that this thing comes as a mounting kit so if I can find a pvc tube long enough of the same diameter it should be fine to mount the ends. Am I thinking correctly or is this to big to be practical?
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post #73 of 158 Old 05-06-2014, 04:42 AM - Thread Starter
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OK, now I've narrowed my choices.

I'm reduced to 1 closed sub-woofer and 7 vented ones. 36 others were eliminated in the process, either because comparing with the chosen ones they perform worse or simply because they are too expensive.

These are my candidates in alphabetical order:

Dayton Audio RSS390HF-4
Dayton Audio UM12-22
Dayton Audio UM15-22
Dayton Audio UM18-22
Sundown X-15 D2
Sundown X-18 D2 (closed box)
RE Audio MX12 D1
RE Audio SXX12

So, as you can see I have a selection of 12", 15" and 18" drivers. The cabinet volume will be 230l and the tuning at 13Hz.
As to be expected it's easier to get more oomph with the big woofers although the smaller ones can be pushed lower in the spectrum.
My target was always to beat two SVS PC13-Ultra subs hands down for about half the price.
I will not quite succeed on the budget however as I will exceed it a little but if the result is as expected than I'll be more than happy.

All this being said I've made my choice already and it's a surprising one or perhaps not smile.gif
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post #74 of 158 Old 05-06-2014, 05:07 AM
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You could exceed the SVS subs with either duel Dayton UM18's or even UM15's! Only problem, and as I have already mentioned, the UM18 is not currently available. I am not familiar with those other drivers you mentioned. Why are you considering the HO18 from Dayton? What ever you go with, I would definitely go with a vented enclosure!
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post #75 of 158 Old 05-06-2014, 06:02 AM
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Originally Posted by cochinada View Post


Indeed! I never thought this field was editable.
I'm thinking that if I go for a vented box I won't be needing an LT so, if with the iNuke3000DSP it's possible to define let's say 3 or more EQ filters together with a HP with enough accuracy as allowing 1Hz and 0.5dB steps and even better decimal changes in Q, I guess I can save a hundred Euro and skip the miniDSP. I believe you have an iNuke right? Can you tell me if these things are all possible?
Well me neither as I never purchased one but I reckon that it's not going to be easy to find one longer than 1292mm.
I could push 140W maximum as more than that and the cone excursion at 10Hz goes beyond 22mm. With a HP (Butterwoth, n=2, fc=8,00Hz).

But there is another trade-off as the 1st port resonance lowers dangerously from 158.75Hz to 132.95Hz. eek.gif

 

I don't have an iNuke, I have a non dsp-Behringer amp and a minidsp, so I don't know exactly what those amps are capable of. I can tell you for sure that minidsp can do those things lol.

 

It's pretty easy over here to find 2.5 meter long pvc at home improvement stores. That would probably be your best bet for simplicity. I did almost exactly what you're talking about with the precision ports from parts express. I used a pvc 90 degree bend and all my other parts were precision port. I was able to find pvc that was pretty close, but it wasn't perfect, so I had to wrap tape around the outside of the precision port tubes to get them to fit tight. If you could find long enough pvc, it would probably be easier and a lot cheaper to make your port that way. 

 

I'll admit I don't know much about port resonances. You could shorten the port and keep your tune the same if you made your enclosures bigger, but I don't think you're able to do that. 

 

I don't have any experience with those drivers except for my um12, but unless they model better than the mx12, that one looks really good for your goals.

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post #76 of 158 Old 05-06-2014, 07:09 AM - Thread Starter
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Originally Posted by Martycool007 View Post

You could exceed the SVS subs with either duel Dayton UM18's or even UM15's! Only problem, and as I have already mentioned, the UM18 is not currently available. I am not familiar with those other drivers you mentioned. Why are you considering the HO18 from Dayton? What ever you go with, I would definitely go with a vented enclosure!

Do you mean the RSS390HF-4? Because it is the second less expensive project on my list and modelled at 103,3 dB @ 15 Hz which is also F3. The UM18-22 by the way reached the highest SPL with 106.668 dB @ 15H z with F3=14.83 Hz. The smaller UM15-22 was almost identical only loosing some punch at frequencies above 20 Hz but because it is cheaper it has an edge. But none of these were my choice.

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I don't have an iNuke, I have a non dsp-Behringer amp and a minidsp, so I don't know exactly what those amps are capable of. I can tell you for sure that minidsp can do those things lol.

Good to hear that because it seems that I'm also going to buy a miniDSP.

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It's pretty easy over here to find 2.5 meter long pvc at home improvement stores. That would probably be your best bet for simplicity. I did almost exactly what you're talking about with the precision ports from parts express. I used a pvc 90 degree bend and all my other parts were precision port. I was able to find pvc that was pretty close, but it wasn't perfect, so I had to wrap tape around the outside of the precision port tubes to get them to fit tight. If you could find long enough pvc, it would probably be easier and a lot cheaper to make your port that way. 

I'll admit I don't know much about port resonances. You could shorten the port and keep your tune the same if you made your enclosures bigger, but I don't think you're able to do that. 

I would have to shop around to see if I could find this. Anyway the assembling and mounting of this huge port inside the cabinet would be a challenge and we also have to consider lots of potential issues such as the resonance and air speed, not to mention the cabinet itself with the cut-off for the port.

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I don't have any experience with those drivers except for my um12, but unless they model better than the mx12, that one looks really good for your goals.

I have to admit that the MX12 D1 on this cabinet is the one that goes lower with F3=11.83 Hz and with 104.812 dB @ 15 Hz came in a respectable 4th position. It was though the 3rd more expensive of the list. Anyway there is always some trade-off not only on the modelling but ultimately on the final choice as if I went for deeper response I would have to sacrifice SPL and vice versa so perhaps the answer was on the middle.

With that being said I've opted for the only closed box on my list. Yes, I'm talking about the Sundown X-18 D2 (or D4). I know it doesn't go as low as the MX12 D1 or the X-15 D2 vented or the UM12-22 or even the RE Audio SXX12 at the same SPL but let me tell you having pondering all pros and cons why I chose this.

1. with a miniDSP I can model whatever LT I wish. For instance I can go as lower as F3=10.41 Hz with 101.279 dB @ 15 Hz or F3=15.14 Hz with 103.968 @ 15 Hz. That gives me the flexibility to tune it according to my taste any day I like which is something that wouldn't be possible with a vented one or at least it would be much more difficult and for sure not so flexible.

2. it hasn't the issues and all the hassle attached to this port thing.

3. the cabinet will be easier to build.

And ultimately I believe that with any LT from 10 Hz to 15 Hz it will beat the SVS hands down.

Your comments are most welcome smile.gif
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post #77 of 158 Old 05-06-2014, 07:35 AM
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Cool that's awesome that you've made up your mind. It will be a lot easier to build and not have to mess with a port. 

 

If you haven't already, you should model any LT's you might be planning to make sure they don't cause excursion past xmax, require more power than your amp can provide, etc.

 

Could you post the winisd project file for this model? I'd like to check it out and play around with it since I've never built a sealed sub. 

 

Just out of curiosity, what level do you normally watch movies at?

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post #78 of 158 Old 05-06-2014, 07:52 AM - Thread Starter
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Originally Posted by TheGiantPeach View Post

Cool that's awesome that you've made up your mind. It will be a lot easier to build and not have to mess with a port. 

If you haven't already, you should model any LT's you might be planning to make sure they don't cause excursion past xmax, require more power than your amp can provide, etc.

Could you post the winisd project file for this model? I'd like to check it out and play around with it since I've never built a sealed sub. 

Just out of curiosity, what level do you normally watch movies at?

Thanks! Yes I've already modelled these 4 different LT's and they all use the same amplifier apparent power as I had to adjust at the same time the level of the system input to not overcome the Xmax.
By all means here it is:

Closed.zip 4k .zip file

Tell me if it's OK. smile.gif

About the level I'm not sure but I'm not deaf and my girlfriend doesn't like it very loud also. At the moment I still have an old Meridian 861 and depending on the DVD it can be anything between 65 to 80 more or less.
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post #79 of 158 Old 05-06-2014, 08:10 AM
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Thanks! Yes I've already modelled these 4 different LT's and they all use the same amplifier apparent power as I had to adjust at the same time the level of the system input to not overcome the Xmax.
By all means here it is:

Closed.zip 4k .zip file

Tell me if it's OK. smile.gif

About the level I'm not sure but I'm not deaf and my girlfriend doesn't like it very loud also. At the moment I still have an old Meridian 861 and depending on the DVD it can be anything between 65 to 80 more or less.

 

Looks pretty good as long as you're okay with it requiring that much power. Your LT makes the response much much better, but it takes a 42 watt input signal and requires more than 1000 watts! Everything else looks good though. Have you figured out what amps you want to power these with? 

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post #80 of 158 Old 05-06-2014, 08:16 AM - Thread Starter
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Yes. It has to be an iNuke6000 (no need for DSP) with 2120W RMS @ 4Ohm and a miniDSP for the LT.
I read somewhere that Behringer announces the power figures not in RMS but in peak value so that's why I got this value of 2120.

I still have to decide which is better: the X-18 D2 or D4, the difference being on the impedance only.
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post #81 of 158 Old 05-06-2014, 08:29 AM
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Yes. It has to be an iNuke6000 (no need for DSP) with 2120W RMS @ 4Ohm and a miniDSP for the LT.
I read somewhere that Behringer announces the power figures not in RMS but in peak value so that's why I got this value of 2120.

I still have to decide which is better: the X-18 D2 or D4, the difference being on the impedance only.

 

This bench test found the iNuke 6000 was good for 1800 watts per channel x 2 channels at 4ohms. So you might even want to consider a bigger amp, or two 1500 watt amps or something. 

 

If the only difference between those subs is the impedance, then you probably want the D2, it's a dual voice coil, so you would wire the voice coils in series for a total impedance of 4ohms. 

 

Unless you wanted to run both of your subs on one amp channel. Then you could get the D4, wire the voice coils in parallel for a total of 2 ohms per driver, and then wire both subs in series for 4 ohms total.

 

Just depends on how you want to do it. 

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post #82 of 158 Old 05-06-2014, 08:40 AM - Thread Starter
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Originally Posted by TheGiantPeach View Post

This bench test found the iNuke 6000 was good for 1800 watts per channel x 2 channels at 4ohms. So you might even want to consider a bigger amp, or two 1500 watt amps or something.

You got me confused. I will only need about 1360W per channel so I guess 1800 is more than enough. smile.gif

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If the only difference between those subs is the impedance, then you probably want the D2, it's a dual voice coil, so you would wire the voice coils in series for a total impedance of 4ohms.

Unless you wanted to run both of your subs on one amp channel. Then you could get the D4, wire the voice coils in parallel for a total of 2 ohms per driver, and then wire both subs in series for 4 ohms total.

Just depends on how you want to do it.

I will have two separate channels, one for each sub-woofer. My processor will have 8.2 outputs.

Question: you connect your miniDSB to the sub-woofer output of the AV receiver/processor, then to the Behringer and finally to the sub-woofer, right?
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post #83 of 158 Old 05-06-2014, 08:50 PM
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with the inuke 6000, you want 4 ohms net per channel.

if the svs uses the same driver as the ultra and the same amp, it will probably have similar performance. that performance is roughly modeled by the red line.

the blue line is the sundown x with 1500 watts in 8 cubic feet (~240l or so) which pushes the driver to xmax (no inductance effects shown).



so around the tuning frequency of the ported sub, it is tough to beat it with a sealed sub. for that reason, the ported sub might be best for most folks.

to the extent that you want frequencies less than 15hz, the sealed will have more. in either case, that's quite a bit of bass, so you'll be quite happy.

like i mentioned earlier though, you will have some room gain so won't need all the eq that you keep adding in to make the curve flat. ;-)
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post #84 of 158 Old 05-06-2014, 11:43 PM - Thread Starter
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The PC13-Ultra has a 13,5" driver according to the information on the SVS site. I will have an 18". So here I guess I have an advantage at least theoretically.

I didn't use much if any equalization this time. Only an LT tuned to a custom frequency. smile.gif

The room gain will be the icing on the cake and perhaps I can use an LT with an Fp higher which will also give me more SPL.

By the way, since mine will be a down firing sub-woofer what space do you recommend I keep between the driver and the floor? This Sundown X-18 has about two inches of rubber standing out of the profile...

Someone told me that for the SVS PC13-Ultra "It's around an inch to an inch and a quarter." That little? For sure the minimum in the Sundown X-18 is two inches just to clear that huge rubber lip it has.




Thanks!
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post #85 of 158 Old 05-07-2014, 09:17 AM
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You got me confused. I will only need about 1360W per channel so I guess 1800 is more than enough. smile.gif
I will have two separate channels, one for each sub-woofer. My processor will have 8.2 outputs.

Question: you connect your miniDSB to the sub-woofer output of the AV receiver/processor, then to the Behringer and finally to the sub-woofer, right?

 

Correct. You just get terminal blocks on the minidsp, so you can choose how to wire it. I wired a female rca to each input and a female balanced trs cable to each output. So I can just plug the rca from the receiver into it and then a trs cable from it to the amp. You will want the balanced version of the 2x4 minidsp. And since you're ordering from them already, grab their UMIK-1 measurement mic if you have a little extra money. Each mic is measured and each gets a calibration file so it's dead accurate. Then you can measure what your subs are actually doing in your room and make pretty graphs in REW :)  It helps with setting up EQs and compensating from room effects. 

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post #86 of 158 Old 05-07-2014, 09:34 AM - Thread Starter
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Correct. You just get terminal blocks on the minidsp, so you can choose how to wire it. I wired a female rca to each input and a female balanced trs cable to each output. So I can just plug the rca from the receiver into it and then a trs cable from it to the amp. You will want the balanced version of the 2x4 minidsp. And since you're ordering from them already, grab their UMIK-1 measurement mic if you have a little extra money. Each mic is measured and each gets a calibration file so it's dead accurate. Then you can measure what your subs are actually doing in your room and make pretty graphs in REW smile.gif  It helps with setting up EQs and compensating from room effects. 


Errr why will I want the balanced version?
I'm on a tight budget right now and I have to save all I can as I already ordered the drivers. But my new receiver comes with a good mic they say.
Any hunch about the distance from the floor? I think an up firing sub-woofer would be awkward...
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post #87 of 158 Old 05-07-2014, 09:44 AM
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Errr why will I want the balanced version?
I'm on a tight budget right now and I have to save all I can as I already ordered the drivers. But my new receiver comes with a good mic they say.
Any hunch about the distance from the floor? I think an up firing sub-woofer would be awkward...

 

The balanced one has higher voltage outputs, and pro amps tend to need higher voltage inputs. I originally had mine hooked up with just rca (unbalanced) from minidsp to my amp, and i had the amp turned up all the way and it wasn't even close to enough gain. 

 

What receiver are you getting? If you're getting one with Audyseey SubEQ, and you aren't going to need a high pass, you could probably skip the minidsp for now and add it later if you want more control. 

 

I don't know about the distance from the floor. I would guess that as long as the area between the sub and the floor is greater than the surface area of the speaker, you would be okay.

So something like (pi * diameter of speaker * distance from floor) needs to be more than (pi * radius of speaker squared).

But that's just a guess... and that's assuming you have room on all sides of the sub and it's not pushed right up to a wall. 

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post #88 of 158 Old 05-07-2014, 10:26 AM - Thread Starter
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The balanced one has higher voltage outputs, and pro amps tend to need higher voltage inputs. I originally had mine hooked up with just rca (unbalanced) from minidsp to my amp, and i had the amp turned up all the way and it wasn't even close to enough gain. 

What receiver are you getting? If you're getting one with Audyseey SubEQ, and you aren't going to need a high pass, you could probably skip the minidsp for now and add it later if you want more control. 

I don't know about the distance from the floor. I would guess that as long as the area between the sub and the floor is greater than the surface area of the speaker, you would be okay.
So something like (pi * diameter of speaker * distance from floor) needs to be more than (pi * radius of speaker squared).
But that's just a guess... and that's assuming you have room on all sides of the sub and it's not pushed right up to a wall. 

An Anthem AVM 50v 3D with ANTHEM ROOM CORRECTION (ARC).
How can I skip the miniDSP? What about the LT?

What a strange formula! Manipulating it a little bit,

since diameter of speaker = 2 x radius of speaker then...

2 x pi x radius of speaker x distance from floor > pi x radius of speaker squared or...

2 x distance from floor > radius of speaker

and finally...

distance from floor > radius of speaker / 2

which gives...

distance from floor > 213mm eek.gifeek.gifeek.gif

This is much more than the distance on the SVS apparently...
The subs will be placed like on the picture I posted earlier, so not much room at all.
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post #89 of 158 Old 05-07-2014, 10:45 AM
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Oh right I forgot about the LT you were planning. Just trying to save you some money initially. 

 

Yeah I just kinda made up that formula because I don't you don't want to restrict airflow from the driver, same as you don't want to restrict it from the ports. Your 18 inch has much more surface area than the svs driver, so I guess that makes sense. You're going to be moving a ton of air, especially since you're going to have such low frequency response.

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post #90 of 158 Old 05-07-2014, 11:13 AM - Thread Starter
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Yes that makes sense but this poses some engineering problems as I would have to raise it significantly which means some feet about 220mm x 35mm.
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