What Type of crossover to use for tuba 30

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Bigrob1234
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What Type of crossover to use for tuba 30

#1 Post by Bigrob1234 »

Hi, I've recently built 2 tuba 30 subwoofers, paired with behringer nx3000D amplifier with all these cool crossover curve options.
I'm not sure what filter I should go with for the high pass filter. Currently I have it set to LR24 for high pass and BUT18 for low pass. Any advice on how to set my filters properly is greatly appreciated!! And if someone wants to explain the differences between all the filter should be much appreciate aswell. I've done some googling but I seem to be more confused now:(

Grant Bunter
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Re: What Type of crossover to use for tuba 30

#2 Post by Grant Bunter »

Hi and welcome :)
Hi, I've recently built 2 tuba 30 subwoofers
Pictures and a build thread, or it didn't happen :)

You haven't given us quite enough info;
What values in Hz did you set each of these settings at?
Also, where is your brick wall limiter?
It's the limiter that's going to protect your investment.

Crossover slopes/filter types:
Don't get too excited about these at this early stage.
It is sufficient to know for now that they cause drop off in response at a predictable rate (because they are expressed as a reduction in dB per octave), yet different slope types have different attributes.

By far and away the best way to get to know slope types is to play with them until you find what suits you sound wise, yet still does the job.

What are you using for tops/mains?
Built:
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" KL3010LF , 2 x 28" 3012LF.
WH8: x 6 with melded array wired series/parallel.
Bunter's Audio and Lighting "like"s would be most appreciated...

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Seth
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Re: What Type of crossover to use for tuba 30

#3 Post by Seth »

Hey Rob, welcome to the forum!

What driver did you use?
How wide did you build your cabs?
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

Bigrob1234
Posts: 33
Joined: Sun Feb 05, 2023 4:56 am

Re: What Type of crossover to use for tuba 30

#4 Post by Bigrob1234 »

Seth wrote: Tue Feb 07, 2023 7:01 pm Hey Rob, welcome to the forum!

What driver did you use?
How wide did you build your cabs?
I built then 24 inches wide (using 23 inch wide internal panels)

I'm using the eminence lab 12 as my drivers

Thank you :D

Bigrob1234
Posts: 33
Joined: Sun Feb 05, 2023 4:56 am

Re: What Type of crossover to use for tuba 30

#5 Post by Bigrob1234 »

Grant Bunter wrote: Mon Feb 06, 2023 4:32 pm Hi and welcome :)
Hi, I've recently built 2 tuba 30 subwoofers
Pictures and a build thread, or it didn't happen :)

You haven't given us quite enough info;
What values in Hz did you set each of these settings at?
Also, where is your brick wall limiter?
It's the limiter that's going to protect your investment.

Crossover slopes/filter types:
Don't get too excited about these at this early stage.
It is sufficient to know for now that they cause drop off in response at a predictable rate (because they are expressed as a reduction in dB per octave), yet different slope types have different attributes.

By far and away the best way to get to know slope types is to play with them until you find what suits you sound wise, yet still does the job.

What are you using for tops/mains?

I'm currently using some older Yamaha BR15 as my tops however, I hope to upgrade these when I can. I've set the crossover to 30 hz as high pass and 80hz for low pass.
I don't have a current limiter in place and the dsp settings are so damn confusing so I'm not sure how to set it.

Also tbh, maybe my ears aren't trained enough but it's hard to notice a difference between the different slope options I have, I've simply gone off someone else's recommendations.
I have also attached some pictures for you 8)
Attachments
20230205_162016.jpg
20230205_162034.jpg

Grant Bunter
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Re: What Type of crossover to use for tuba 30

#6 Post by Grant Bunter »

Bigrob1234 wrote: Thu Feb 09, 2023 12:21 am I've set the crossover to 30 hz as high pass and 80hz for low pass.
The following is directly from my older set of plans:
The Lab 12 also must be limited to 50 volts.
Groups of less than four cabs should be high-passed at 35 Hz. With four cabs or more 30 Hz is acceptable.
You can see it says must be limited, not maybe/should/could/choose to.
These aren't like normal direct radiator cabs. They don't complain when they get near to their operating limit, they just stop working.

Similarly, the high pass must be 35Hz, not 30Hz, because you only have 2 cabs.
Both of these are directly from the man who designed the cabs. Listen to him.
Yes it matters.
Bigrob1234 wrote: Thu Feb 09, 2023 12:21 amI'm currently using some older Yamaha BR15 as my tops however, I hope to upgrade these when I can.
The specs say these cabs are good from 60Hz up, but there isn't an SPL chart in the literature to support that statement.
The Tuba 30 will do 80Hz up to 100Hz much better than the Yammy's will do down to 80 hz or 60Hz.
I would be inclined to suggest using steeper slopes initially (24dB/octave) for the HP for the Yammies.
Either LR or Butterworth.
You do have a crossover for the tops yeah?
Bigrob1234 wrote: Thu Feb 09, 2023 12:21 amI don't have a current limiter in place and the dsp settings are so damn confusing so I'm not sure how to set it.
Please see above.
A quick look at the manual didn't really show me if the limiter was adequate for purpose, so I'll leave that to an Inuke user to answer.
The general answer though is that there a very few DSP amps out there that brick wall limit.
Bigrob1234 wrote: Thu Feb 09, 2023 12:21 amAlso tbh, maybe my ears aren't trained enough but it's hard to notice a difference between the different slope options I have, I've simply gone off someone else's recommendations.
The differences can be subtle, but will be more pronounced when you A/B them with steeper slopes until you can start to recognise differences.
Running sound requires retraining our brains for nearly all of us by and large, it can take some time.
Bigrob1234 wrote: Thu Feb 09, 2023 12:21 amI have also attached some pictures for you 8)
Thank you. The pics aren't for me. They are for anyone else who wants to see what T30's look like. Most people will look through build threads. It may not occur for them to look at a T30/crossover thread.

Having said that, your pics told me something.
They told me that your inclination is to set up aesthetically, not functionally.
To get the best out of your subs, they need to be set up for functionality.
Please read and learn this:
viewtopic.php?t=398
We call it the sub placement sticky.

The reason I recommend this is: your subs have been placed contrary to the prime directive in the sub sticky, so they may be causing cancellations within each other.
Put the subs immediately side by side, and face them at the wall, the mouths about 8 inches from the wall.
You might be quite surprised at the difference.

Just so you know, I'm not picking on you. If someone doesn't tell you you may be doing something incorrectly, you'll never learn.
We all start somewhere...
Built:
DR 250: x 2 melded array, 2x CD horn, March 2012 plans.
T39's: 4 x 20" KL3010LF , 2 x 28" 3012LF.
WH8: x 6 with melded array wired series/parallel.
Bunter's Audio and Lighting "like"s would be most appreciated...

Bigrob1234
Posts: 33
Joined: Sun Feb 05, 2023 4:56 am

Re: What Type of crossover to use for tuba 30

#7 Post by Bigrob1234 »

Grant Bunter wrote: Thu Feb 09, 2023 1:32 am
Bigrob1234 wrote: Thu Feb 09, 2023 12:21 am I've set the crossover to 30 hz as high pass and 80hz for low pass.
The following is directly from my older set of plans:
The Lab 12 also must be limited to 50 volts.
Groups of less than four cabs should be high-passed at 35 Hz. With four cabs or more 30 Hz is acceptable.
You can see it says must be limited, not maybe/should/could/choose to.
These aren't like normal direct radiator cabs. They don't complain when they get near to their operating limit, they just stop working.

Similarly, the high pass must be 35Hz, not 30Hz, because you only have 2 cabs.
Both of these are directly from the man who designed the cabs. Listen to him.
Yes it matters.
Bigrob1234 wrote: Thu Feb 09, 2023 12:21 amI'm currently using some older Yamaha BR15 as my tops however, I hope to upgrade these when I can.
The specs say these cabs are good from 60Hz up, but there isn't an SPL chart in the literature to support that statement.
The Tuba 30 will do 80Hz up to 100Hz much better than the Yammy's will do down to 80 hz or 60Hz.
I would be inclined to suggest using steeper slopes initially (24dB/octave) for the HP for the Yammies.
Either LR or Butterworth.
You do have a crossover for the tops yeah?
Bigrob1234 wrote: Thu Feb 09, 2023 12:21 amI don't have a current limiter in place and the dsp settings are so damn confusing so I'm not sure how to set it.
Please see above.
A quick look at the manual didn't really show me if the limiter was adequate for purpose, so I'll leave that to an Inuke user to answer.
The general answer though is that there a very few DSP amps out there that brick wall limit.
Bigrob1234 wrote: Thu Feb 09, 2023 12:21 amAlso tbh, maybe my ears aren't trained enough but it's hard to notice a difference between the different slope options I have, I've simply gone off someone else's recommendations.
The differences can be subtle, but will be more pronounced when you A/B them with steeper slopes until you can start to recognise differences.
Running sound requires retraining our brains for nearly all of us by and large, it can take some time.
Bigrob1234 wrote: Thu Feb 09, 2023 12:21 amI have also attached some pictures for you 8)
Thank you. The pics aren't for me. They are for anyone else who wants to see what T30's look like. Most people will look through build threads. It may not occur for them to look at a T30/crossover thread.

Having said that, your pics told me something.
They told me that your inclination is to set up aesthetically, not functionally.
To get the best out of your subs, they need to be set up for functionality.
Please read and learn this:
viewtopic.php?t=398
We call it the sub placement sticky.

The reason I recommend this is: your subs have been placed contrary to the prime directive in the sub sticky, so they may be causing cancellations within each other.
Put the subs immediately side by side, and face them at the wall, the mouths about 8 inches from the wall.
You might be quite surprised at the difference.

Just so you know, I'm not picking on you. If someone doesn't tell you you may be doing something incorrectly, you'll never learn.
We all start somewhere...
[/quote


Thank you so much for all the info, I completely agree with all the issues you have mentioned, I do still have a long way to go when it comes to all the knowledge required.

The limiter included with the amp has a threshold, rtime and hold setting. I'm not sure what to do with that but I'll do some more research.

Unfortunately I cannot face the subs against the "wall" behind them as the "wall" is actually just glass sliding doors with curtains infront :(

I'll also change the crossover to 35 hz and I guess do some more experimenting with appropriate filters.

Thanks again!!

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Bill Fitzmaurice
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Re: What Type of crossover to use for tuba 30

#8 Post by Bill Fitzmaurice »

Bigrob1234 wrote: Thu Feb 09, 2023 6:23 am Unfortunately I cannot face the subs against the "wall" behind them as the "wall" is actually just glass sliding doors with curtains infront
Yes, you may. If you think the doors will rattle more that's not the case, the output pattern of any sub is 360 degrees. Aiming them backwards insures that you won't have boundary reflection cancellations, and it acoustically filters above bandwidth content.

Bigrob1234
Posts: 33
Joined: Sun Feb 05, 2023 4:56 am

Re: What Type of crossover to use for tuba 30

#9 Post by Bigrob1234 »

I have another question aswell,

I'm in the middle of setting limiter on my amplifier, I have all levels on mixer set to 0db and amplifier is set to max, I am playing 57 hz tone through the system and using a multimeter to measure voltage. Currently, with a threshold of 0db set on amplifier, multimeter is only reading 47 volts, below the recommended 50 v limit. Does this mean I can blast music through this now at the same settings and my subs will be fine? Thanks

Bruce Weldy
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Re: What Type of crossover to use for tuba 30

#10 Post by Bruce Weldy »

Bigrob1234 wrote: Thu Feb 09, 2023 8:06 am Currently, with a threshold of 0db set on amplifier, multimeter is only reading 47 volts, below the recommended 50 v limit. Does this mean I can blast music through this now at the same settings and my subs will be fine? Thanks
That amp states a rating of 440 watts at 8 ohms. The Lab 12 is a 6 ohm driver - thus the voltage output is 51 volts. And since Behringer is notorious for fudging their output numbers.....I'm surprised you are even getting 47 out of it.

I don't know if you have stated exactly what you are using these for....live sound? DJ? Here's the deal. The voltage limits are there to stop over-excursion of the cone of the driver. Can you run it 30hz? Sure, as long as you don't put much power to it. So, safety is determined by both frequency and power. The high pass and the voltage ratings in the plans ensure that you can hit both without blowing a driver.

So, raise the high-pass and you can give it the full power of the amp....BUT.....you can't be overdriving the input stage of the amp (which is the only way I've ever gotten a Behringer amp to it's stated output) or you can start clipping that amp and invite disaster. My advice would be to limit to about 45 volts, just so you are sure that the limiter will engage if things get pushed to far.

6 - T39 3012LF
4 - OT12 2512
1 - T24
1 - SLA Pro
2 - XF210


"A system with a few knobs set up by someone who knows what they are doing is always better than one with a lot of knobs set up by someone who doesn't."

Bigrob1234
Posts: 33
Joined: Sun Feb 05, 2023 4:56 am

Re: What Type of crossover to use for tuba 30

#11 Post by Bigrob1234 »

Bruce Weldy wrote: Thu Feb 09, 2023 9:22 am
Bigrob1234 wrote: Thu Feb 09, 2023 8:06 am Currently, with a threshold of 0db set on amplifier, multimeter is only reading 47 volts, below the recommended 50 v limit. Does this mean I can blast music through this now at the same settings and my subs will be fine? Thanks
That amp states a rating of 440 watts at 8 ohms. The Lab 12 is a 6 ohm driver - thus the voltage output is 51 volts. And since Behringer is notorious for fudging their output numbers.....I'm surprised you are even getting 47 out of it.

I don't know if you have stated exactly what you are using these for....live sound? DJ? Here's the deal. The voltage limits are there to stop over-excursion of the cone of the driver. Can you run it 30hz? Sure, as long as you don't put much power to it. So, safety is determined by both frequency and power. The high pass and the voltage ratings in the plans ensure that you can hit both without blowing a driver.

So, raise the high-pass and you can give it the full power of the amp....BUT.....you can't be overdriving the input stage of the amp (which is the only way I've ever gotten a Behringer amp to it's stated output) or you can start clipping that amp and invite disaster. My advice would be to limit to about 45 volts, just so you are sure that the limiter will engage if things get pushed to far.

Thank you, I will be playing mostly house/dnb music through it, so lots of heavy bass. Also I'd like to note that the amp limit light illuminates well before it I turn volume up to max, does this just mean the limiter is engaging before max volume is reached or do I have my input levels set too high? Does this mean I should turn down gain on the mixer? Cheers

Bruce Weldy
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Re: What Type of crossover to use for tuba 30

#12 Post by Bruce Weldy »

Bigrob1234 wrote: Fri Feb 10, 2023 3:42 am
Thank you, I will be playing mostly house/dnb music through it, so lots of heavy bass. Also I'd like to note that the amp limit light illuminates well before it I turn volume up to max, does this just mean the limiter is engaging before max volume is reached or do I have my input levels set too high? Does this mean I should turn down gain on the mixer? Cheers
Honestly, you need a bigger amp that will let you run up to the voltage limit without overdriving the amp. I couldn't find anything other than the quick-start guide and that gave no info on the limiter. You could bridge the amp, but then you'd be running a 3 ohm load.....would it damage the amp? Probably not unless you drive it to war volume all the time. But, you would absolutley have to make sure your voltage limit is correct and holding so as not to blow up the drivers. Or, you just build two more cabs if you aren't getting the bottom end that you want.

6 - T39 3012LF
4 - OT12 2512
1 - T24
1 - SLA Pro
2 - XF210


"A system with a few knobs set up by someone who knows what they are doing is always better than one with a lot of knobs set up by someone who doesn't."

Bigrob1234
Posts: 33
Joined: Sun Feb 05, 2023 4:56 am

Re: What Type of crossover to use for tuba 30

#13 Post by Bigrob1234 »

Thank you all very much for all the info you have provided :D

I really do appreciate it and I believe I have most of it figured out now!! Thanks again!

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Seth
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Re: What Type of crossover to use for tuba 30

#14 Post by Seth »

Bigrob1234 wrote: Fri Feb 10, 2023 3:42 am ...the amp limit light illuminates well before it I turn volume up to max... ...do I have my input levels set too high? Does this mean I should turn down gain on the mixer? Cheers
Sounds like a gain structure issue to me. What mixer are you using?
Build in process - 2 WH6, one Alpha 6a loaded, one PRV Audio 6MB250-NDY loaded

Two 2x6 shorty SLA Pro's
One T39, 16", 3012LF loaded
Tall AutoTuba, 20" wide, 2x 8" MCM 55-2421
TruckTuba, 8½" wide, 2x 8" MCM 55-2421

Bigrob1234
Posts: 33
Joined: Sun Feb 05, 2023 4:56 am

Re: What Type of crossover to use for tuba 30

#15 Post by Bigrob1234 »

Seth wrote: Sat Feb 11, 2023 8:10 am
Bigrob1234 wrote: Fri Feb 10, 2023 3:42 am ...the amp limit light illuminates well before it I turn volume up to max... ...do I have my input levels set too high? Does this mean I should turn down gain on the mixer? Cheers
Sounds like a gain structure issue to me. What mixer are you using?
I'm using a Yamaha mg06 mixer, I have my inputs plugged into ch1 and 2 using xlr to rca converter plugs

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