Subwoofer output css sdx

[Stones]

Hello,
I have recently added two css sdx 12” subwoofers up front each with its own crown xls 2002 bridged ( 2100 watts ) and two css sdx 10” in rear powered by a behringer km 1700 ( about 400 watts per ch.) all In sealed enclosures built to spec.
My front speakers are 3 Boston acoustic vr m90’s and both My side and rear surrounds are Boston vr m60.
The bostons are powered by a Yamaha rxv 2700. With a mini dsp HD.
My room is L shaped. The main part 14 x 18 with a 9x 10 making up the smaller part of the L shaped room.
My question .
I assumed I would get more volume out of my subs . I have to turn the gain down through my reciever on all my speaker to -4 to level match my subs.
If I turn the the gain on my crowns past 3 o’clock I get clipping and my subs can bottom out .
I do have the output gain sat on my mini dsp Hd set so that at max volume on avr ( I limit it to -10) with Jurassic park scene I use to test limits I don’t go into the red with the gain.
I love my set up and I think the css sdx subs sound great but I feel like I am doing something wrong and my output is suffering .
Are my expectations to high?
I bought the crowns because they claim 2100 watts and my subs are 1000 watts rms so I thought I would have plenty of headroom but I seem to be at the limits . I do have my crown amp sensitivity set to the lowest option .
Also the two sdx 10” running off the 400 watt behringer are only a couple of db below the 12” sdx running off the 2100 watt crown.
Just doesn’t seem right.

 

[TLS Guy]

Hello,
I have recently added two css sdx 12” subwoofers up front each with its own crown xls 2002 bridged ( 2100 watts ) and two css sdx 10” in rear powered by a behringer km 1700 ( about 400 watts per ch.) all In sealed enclosures built to spec.
My front speakers are 3 Boston acoustic vr m90’s and both My side and rear surrounds are Boston vr m60.
The bostons are powered by a Yamaha rxv 2700. With a mini dsp HD.
My room is L shaped. The main part 14 x 18 with a 9x 10 making up the smaller part of the L shaped room.
My question .
I assumed I would get more volume out of my subs . I have to turn the gain down through my reciever on all my speaker to -4 to level match my subs.
If I turn the the gain on my crowns past 3 o’clock I get clipping and my subs can bottom out .
I do have the output gain sat on my mini dsp Hd set so that at max volume on avr ( I limit it to -10) with Jurassic park scene I use to test limits I don’t go into the red with the gain.
I love my set up and I think the css sdx subs sound great but I feel like I am doing something wrong and my output is suffering .
Are my expectations to high?
I bought the crowns because they claim 2100 watts and my subs are 1000 watts rms so I thought I would have plenty of headroom but I seem to be at the limits . I do have my crown amp sensitivity set to the lowest option .
Also the two sdx 10” running off the 400 watt behringer are only a couple of db below the 12” sdx running off the 2100 watt crown.
Just doesn’t seem right.

We are missing vital information from your post. That is, what enclosure are those sub drivers in? Your Yamaha has enough voltage from the sub out to drive those amps.

So I have to conclude that either those sub drivers are in the wrong box, or that you have them in a sealed box, but have not provided the requisite 12 db per octave boost below F3, and the high pass filter at xmax to prevent over excursion is they are in the optimal sealed box.

The 12" drivers are capable of an F3 of 24 Hz in a ported box, but 45 Hz in a sealed box without appropriate Eq. I have not modeled those drivers, but that is the info from the spec. sheet. If you just threw those drivers in any old box that is your problem. Sub design is an art that has to be learned. Other speakers are even tougher.

So you have only provided details on the sub driver, and that is not even really half of the sub equation.

 

[lovinthehd]

Is it the same kit as in this article ? https://www.audioholics.com/subwoofer-reviews/css-sdx12

 

[Stones]

We are missing vital information from your post. That is, what enclosure are those sub drivers in? Your Yamaha has enough voltage from the sub out to drive those amps.

So I have to conclude that either those sub drivers are in the wrong box, or that you have them in a sealed box, but have not provided the requisite 12 db per octave boost below F3, and the high pass filter at xmax to prevent over excursion is they are in the optimal sealed box.

The 12" drivers are capable of an F3 of 24 Hz in a ported box, but 45 Hz in a sealed box without appropriate Eq. I have not modeled those drivers, but that is the info from the spec. sheet. If you just threw those drivers in any old box that is your problem. Sub design is an art that has to be learned. Other speakers are even tougher.

So you have only provided details on the sub driver, and that is not even really half of the sub equation.

Thanks for responding.
The 12” sdx are in a 1.2 Cu ft. Sealed boxes. and the 10” sdx’s are in a .75 cu ft. Sealed boxes. I chose the sizes from the css recommendations for a qtc of .707 for the 12” and added foam board to the 10” to get .75 cu ft. For the 10” because I found the css recommendation of 1. Cu ft for the 10” to big and the 10” would bottom out.
I set my high pass for 27 hz for the 12” and 28hz for the 10”. The 12” have a 5db boost at 30hz and the 10” have a 2.5 hz boost at 30 hz. Per css recommendations , but lowered the boost on the 10” to protect woofer.
The rest of the eq remains flat.
I chose theses numbers both from the audiobook s article about the css 12” and from calling and speaking to someone at css.
They actually recommend a high pass at 25 hz but I moved it up for added protection.
Thanks again

 

[Stones]

Thanks for responding.
The 12” sdx are in a 1.2 Cu ft. Sealed boxes. and the 10” sdx’s are in a .75 cu ft. Sealed boxes. I chose the sizes from the css recommendations for a qtc of .707 for the 12” and added foam board to the 10” to get .75 cu ft. For the 10” because I found the css recommendation of 1. Cu ft for the 10” to big and the 10” would bottom out.
I set my high pass for 27 hz for the 12” and 28hz for the 10”. The 12” have a 5db boost at 30hz and the 10” have a 2.5 hz boost at 30 hz. Per css recommendations , but lowered the boost on the 10” to protect woofer.
The rest of the eq remains flat.
I chose theses numbers both from the audiobook s article about the css 12” and from calling and speaking to someone at css.
They actually recommend a high pass at 25 hz but I moved it up for added protection.
Thanks again

Output Volts from mini dsp Hd is 2 v but if I set sub amps at 1.4 v input I get almost no volume so I have switched the amps to .75 input volts . And made sure the input and output on the mini dsp doesnt get into the Red on clip meters. The amp clip meters never get to red .
Avr output is 2 v and I have it set to 0 db gain on the Yamaha receiver.

thanks

 

[Stones]

Is it the same kit as in this article ? https://www.audioholics.com/subwoofer-reviews/css-sdx12

I did not get the kits but I built the box’s to the same dimensions as the kit

 

[TLS Guy]

I did not get the kits but I built the box’s to the same dimensions as the kit

Well, you should have come here first. Those drivers have far less than ideal Thiele/Small parameters for a sealed design and will not work well in such an application. You have inadequate Eq, but I suspect the drivers will not tolerate more. Sealed enclosures are very inefficient as you have found out.

So you need to get your tool kit out, and build ported boxes for those drivers. If you want I can design optimal ported enclosures for you.

With the further information I can see why you have the problem you have, which is exactly what you would be predicted.

 

[Stones]

Well, you should have come here first. Those drivers have far less than ideal Thiele/Small parameters for a sealed design and will not work well in such an application. You have inadequate Eq, but I suspect the drivers will not tolerate more. Sealed enclosures are very inefficient as you have found out.

So you need to get your tool kit out, and build ported boxes for those drivers. If you want I can design optimal ported enclosures for you.

With the further information I can see why you have the problem you have, which is exactly what you would be predicted.

A box design would be great and much appreciated if you have the time. The reason I did not go with a ported box is css advised not to use a port but to use there passive radiators and those are a $100 each and each box needs 2 . So for me that would be another $800. I enjoy building boxes but ported boxes are more complicated to design correctly and I was not sure how to use winsid so I went with the easier design thinking with enough power and 4 woofers I could overcome the inefficient design .

thanks again for your response .

 

[TLS Guy]

A box design would be great and much appreciated if you have the time. The reason I did not go with a ported box is css advised not to use a port but to use there passive radiators and those are a $100 each and each box needs 2 . So for me that would be another $800. I enjoy building boxes but ported boxes are more complicated to design correctly and I was not sure how to use winsid so I went with the easier design thinking with enough power and 4 woofers I could overcome the inefficient design .

thanks again for your response .

It will be my pleasure to assist you. I have a bit going on with the Memorial weekend and some other issues. But I will get to it and send you pdfs. of what I consider to be the optimal design.

A ported enclosure will be just as good as a passive radiator, unless the model shows the port has to be so long, there will be an audible port resonance. I am hoping they just wanted to sell you all those passive radiators, but we will see. The other issue is, you get more low bass from a ported speakers as the roll off is 24db per octave versus 36db per octave for the passive radiator.

 

[Stones]

It will be my pleasure to assist you. I have a bit going on with the Memorial weekend and some other issues. But I will get to it and send you pdfs. of what I consider to be the optimal design.

A ported enclosure will be just as good as a passive radiator, unless the model shows the port has to be so long, there will be an audible port resonance. I am hoping they just wanted to sell you all those passive radiators, but we will see. The other issue is, you get more low bass from a ported speakers as the roll off is 24db per octave versus 36db per octave for the passive radiator.

Thank you ,
No rush

 

[MrBoat]

Have you tried the sub crawl by any chance just to get a feel for the room overall with regard to bass? Not that it works for multiple subs, but a single sub can still tell a lot about the room. All of the bass in my L shaped room ended up at the front door and kitchen.

Worst acoustic space I ever lived with was L shaped. Either way, it took a lot of moving speakers around to find the best places and none of them allowed for normal furniture arrangements to fit with it.

 

[Stones]

Have you tried the sub crawl by any chance just to get a feel for the room overall with regard to bass? Not that it works for multiple subs, but a single sub can still tell a lot about the room. All of the bass in my L shaped room ended up at the front door and kitchen.

Worst acoustic space I ever lived with was L shaped. Either way, it took a lot of moving speakers around to find the best places and none of them allowed for normal furniture arrangements to fit with it.

I suspect my room has a lot to do with my problem. I went back and adjusted the phase of my subs last night . When I first did my REW room adjustment it showed my rear subs should be out of phase with my front subs and the rest of my speakers. But I must have never tried all subs out of phase . It made a big difference . I also lowered the 30hz boost and raised the 75hz and I am much happier with the results. The sub volume is still a little lower than I expected but as you mentioned L shaped rooms can have a negative effect on bass response . Might try to convince the wife that we should put a wall up and make a big closet .

thanks for your help

 

[mtrycrafts]

A box design would be great and much appreciated if you have the time. The reason I did not go with a ported box is css advised not to use a port but to use there passive radiators and those are a $100 each and each box needs 2 . So for me that would be another $800. ...

There is a saying for this: pay now or pay later with hefty interest.

 

[diwit]

Hello,
I have recently added two css sdx 12” subwoofers up front each with its own crown xls 2002 bridged ( 2100 watts ) and two css sdx 10” in rear powered by a behringer km 1700 ( about 400 watts per ch.) all In sealed enclosures built to spec.
My front speakers are 3 Boston acoustic vr m90’s and both My side and rear surrounds are Boston vr m60.
The bostons are powered by a Yamaha rxv 2700. With a mini dsp HD.
My room is L shaped. The main part 14 x 18 with a 9x 10 making up the smaller part of the L shaped room.
My question .
I assumed I would get more volume out of my subs . I have to turn the gain down through my reciever on all my speaker to -4 to level match my subs.
If I turn the the gain on my crowns past 3 o’clock I get clipping and my subs can bottom out .
I do have the output gain sat on my mini dsp Hd set so that at max volume on avr ( I limit it to -10) with Jurassic park scene I use to test limits I don’t go into the red with the gain.
I love my set up and I think the css sdx subs sound great but I feel like I am doing something wrong and my output is suffering .
Are my expectations to high?
I bought the crowns because they claim 2100 watts and my subs are 1000 watts rms so I thought I would have plenty of headroom but I seem to be at the limits of epoxy flooring phoenix. I do have my crown amp sensitivity set to the lowest option .
Also the two sdx 10” running off the 400 watt behringer are only a couple of db below the 12” sdx running off the 2100 watt crown.
Just doesn’t seem right.

It sounds like you have put together an impressive audio setup with multiple subwoofers and speakers. However, there are a few factors that could be contributing to the limitations you're experiencing in terms of volume and performance. Here are some considerations to keep in mind:

1. Room Acoustics: The acoustic properties of your room can significantly impact the performance and perceived volume of your audio system. Factors like room size, shape, and the presence of acoustic treatments or sound-absorbing materials can affect bass response and overall sound quality. It's worth assessing the acoustic characteristics of your room and considering any improvements that could be made.
2. Subwoofer Placement: Subwoofer placement is crucial for achieving optimal performance. Experiment with different locations within your room to find the positions that provide the best bass response and integration with your main speakers. Subwoofer placement guides and tools, such as subwoofer crawl, can help you determine the most effective positioning.
3. Subwoofer Integration: It's important to ensure proper integration and crossover settings between your subwoofers and main speakers. Using a calibration tool like the MiniDSP HD can help you set up appropriate crossover frequencies and adjust phase alignment to achieve a smooth and cohesive sound blend between the subs and the main speakers.
4. Power Handling: While the Crown XLS 2002 amplifiers claim to provide high power output, it's crucial to remember that power ratings alone do not guarantee optimal performance. The efficiency of your subwoofers, the impedance load they present, and the power delivered by the amplifiers all play a role in the actual performance. Make sure you are using appropriate gain settings, and monitor for any signs of distortion or clipping.
5. Personal Expectations: It's possible that your expectations regarding the volume and output capabilities of your system might be set too high. The perception of volume can be influenced by various factors, including room size, listening distance, and personal preferences. It's essential to consider what levels are realistic and enjoyable for your listening environment.

If you have already addressed these considerations and still feel like your system is not performing as expected, it may be beneficial to consult with an audio professional or an experienced home theater enthusiast who can provide personalized advice based on their expertise. They may be able to assess your setup in person and offer recommendations specific to your room and equipment.

Remember that audio performance is a complex interplay of various factors, and achieving the perfect balance requires patience, experimentation, and adjustments based on your specific environment and preferences.

 

[Stones]

It sounds like you have put together an impressive audio setup with multiple subwoofers and speakers. However, there are a few factors that could be contributing to the limitations you're experiencing in terms of volume and performance. Here are some considerations to keep in mind:

1. Room Acoustics: The acoustic properties of your room can significantly impact the performance and perceived volume of your audio system. Factors like room size, shape, and the presence of acoustic treatments or sound-absorbing materials can affect bass response and overall sound quality. It's worth assessing the acoustic characteristics of your room and considering any improvements that could be made.
2. Subwoofer Placement: Subwoofer placement is crucial for achieving optimal performance. Experiment with different locations within your room to find the positions that provide the best bass response and integration with your main speakers. Subwoofer placement guides and tools, such as subwoofer crawl, can help you determine the most effective positioning.
3. Subwoofer Integration: It's important to ensure proper integration and crossover settings between your subwoofers and main speakers. Using a calibration tool like the MiniDSP HD can help you set up appropriate crossover frequencies and adjust phase alignment to achieve a smooth and cohesive sound blend between the subs and the main speakers.
4. Power Handling: While the Crown XLS 2002 amplifiers claim to provide high power output, it's crucial to remember that power ratings alone do not guarantee optimal performance. The efficiency of your subwoofers, the impedance load they present, and the power delivered by the amplifiers all play a role in the actual performance. Make sure you are using appropriate gain settings, and monitor for any signs of distortion or clipping.
5. Personal Expectations: It's possible that your expectations regarding the volume and output capabilities of your system might be set too high. The perception of volume can be influenced by various factors, including room size, listening distance, and personal preferences. It's essential to consider what levels are realistic and enjoyable for your listening environment.

If you have already addressed these considerations and still feel like your system is not performing as expected, it may be beneficial to consult with an audio professional or an experienced home theater enthusiast who can provide personalized advice based on their expertise. They may be able to assess your setup in person and offer recommendations specific to your room and equipment.

Remember that audio performance is a complex interplay of various factors, and achieving the perfect balance requires patience, experimentation, and adjustments based on your specific environment and preferences.

I believe it’s a combination of 1,3,5 in your response . I made a few more adjustment and it has made a big improvement . It can be frustration sometimes because I know it is more likely my lack of knowledge than it is my equipment . I just need to remember its a hobby and that’s part of the fun.
I will start to educate myself on room improvements and see if I can make changes.

Thanks , I really appreciate everyone taking the time to help.

 

[Stones]

There is a saying for this: pay now or pay later with hefty interest.

Haha , very true. After the credit cards cool off I will probably be getting passive resistors

 

[TLS Guy]

Haha , very true. After the credit cards cool off I will probably be getting passive resistors

As promised I have modelled your drivers.

The first point I would make, is that the size of the box is critical to maximize output. Otherwise you reach xmax at a lower power or limit bass output.

These drivers are only suitable for closed box alignment. For ported, the ports are far too long and you will have port resonance. For passive radiator the device has impossible parameters.

I can see why you are having the problems you have. These drivers are actually not all that powerful in the sub range and become power limited. When a manufacturer quotes a power they generally do not state at what frequencies they will take that power. You will see what I am talking about in the attached graph models.

You can see that both drivers require a 12db per octave boost below 50 Hz. You can see that the drivers need protection high passing at 25 Hz or thereabouts.

Now we get to the thorny issue of power handling. The max output of the 12" at 25 Hz is 103db and for the 10" it is 100db.

Now maximum power handling. The 12" can handle 150 watts at 25 Hz before exceeding xmax and getting distressed. The 10" unit can handle just 30 watts at 25 Hz before distress. It actually needs high passing at 30 or 35 Hz. To be honest that driver is pretty useless as a sub driver.

The motor systems of those drivers are not among the best designs. You can see that by the humped response. So the motor systems would benefit from shorting rings.

I return to this point often and that is, that driver selection is always the first step in any speaker build. You have to set your goals and then model drivers until you find one or a number that can fulfil your design goals. If this is omitted, then you will almost certainly be in for a disappointment.

Frankly I would not select either of those drivers for any sub project I was involved with. I really can not sugar cote that news, and in any event that would not be helpful.

 

[Stones]

As promised I have modelled your drivers.

The first point I would make, is that the size of the box is critical to maximize output. Otherwise you reach xmax at a lower power or limit bass output.

These drivers are only suitable for closed box alignment. For ported, the ports are far too long and you will have port resonance. For passive radiator the device has impossible parameters.

I can see why you are having the problems you have. These drivers are actually not all that powerful in the sub range and become power limited. When a manufacturer quotes a power they generally do not state at what frequencies they will take that power. You will see what I am talking about in the attached graph models.

You can see that both drivers require a 12db per octave boost below 50 Hz. You can see that the drivers need protection high passing at 25 Hz or thereabouts.

Now we get to the thorny issue of power handling. The max output of the 12" at 25 Hz is 103db and for the 10" it is 100db.

Now maximum power handling. The 12" can handle 150 watts at 25 Hz before exceeding xmax and getting distressed. The 10" unit can handle just 30 watts at 25 Hz before distress. It actually needs high passing at 30 or 35 Hz. To be honest that driver is pretty useless as a sub driver.

The motor systems of those drivers are not among the best designs. You can see that by the humped response. So the motor systems would benefit from shorting rings.

I return to this point often and that is, that driver selection is always the first step in any speaker build. You have to set your goals and then model drivers until you find one or a number that can fulfil your design goals. If this is omitted, then you will almost certainly be in for a disappointment.

Frankly I would not select either of those drivers for any sub project I was involved with. I really can not sugar cote that news, and in any event that would not be helpful.

Thanks ,
interesting results
I did do a fair amount of research before I bought them including a article from audioholics . This is from their article

“The measured performance of the CSS SDX12 subwoofer is excellent when you consider its price and size. There are other 12” subwoofers that will outperform the SDX12 in pure output, they will typically be more expensive or ported. The deep bass output of this subwoofer is impressive when compared to the commercial competition. There are very few twelve-inch sealed subwoofers that can achieve this level. Further, moving up to the larger dual passive radiator kit is likely to gain 6-9 dB of additional output below 40hz. Hopefully we can test this in the future. “

after reading a bit more on my problem I used REW again and found the my phasing was off and it made a huge difference . I gained another 3-4 db and I was able to turn down amp gain and it dramatically improved my overall sound.

Thank you for your interest/help

Link to article if your interested.

Creative Sound Solutions SDX12 12" Sealed Subwoofer DIY Kit Review

We built and tested the Creative Sound Solutions SDX12 Subwoofer kit. Does the DIY 12" sealed subwoofer kit buy you more performance than commercial offerings? Read on to find out.

www.audioholics.com

 

[TLS Guy]

Thanks ,
interesting results
I did do a fair amount of research before I bought them including a article from audioholics . This is from their article

“The measured performance of the CSS SDX12 subwoofer is excellent when you consider its price and size. There are other 12” subwoofers that will outperform the SDX12 in pure output, they will typically be more expensive or ported. The deep bass output of this subwoofer is impressive when compared to the commercial competition. There are very few twelve-inch sealed subwoofers that can achieve this level. Further, moving up to the larger dual passive radiator kit is likely to gain 6-9 dB of additional output below 40hz. Hopefully we can test this in the future. “

after reading a bit more on my problem I used REW again and found the my phasing was off and it made a huge difference . I gained another 3-4 db and I was able to turn down amp gain and it dramatically improved my overall sound.

Thank you for your interest/help

Link to article if your interested.

Creative Sound Solutions SDX12 12" Sealed Subwoofer DIY Kit Review

We built and tested the Creative Sound Solutions SDX12 Subwoofer kit. Does the DIY 12" sealed subwoofer kit buy you more performance than commercial offerings? Read on to find out.

www.audioholics.com

I guess for the price is somewhat operative here.

However, from an engineering standpoint a sealed sub is an awful idea.

The reason being is that a loudspeaker cone is an absolutely atrocious coupler to air. That is why you have the pretty much useless response before Eq. The only advantage of a sealed design is domestic harmony, after that it ALL downhill.

Loudspeakers for good bass reproduction need an acoustic transformer. That mean a pipe, horn or Helmholtz resonator. Of which the former two are the most efficient, but the least conducive to domestic harmony.

The ported enclosure is a Helmholtz resonator. In the operative FR the cone of the driver almost stops still and the bass is efficiently produced via the port. Below F3 the driver quickly decouples from the box.

Specialized pipes, known as transmission lines can be designed that give broader, more efficient low Q support, which is my favored approach.

Horns are highly efficient, but complex and large.

You just have to consider musical instruments. Pipe organs, flutes and woodwinds like the oboes and clarinets can fill concert halls from the vibrations of small reeds or passage of air over a ledge. The most powerful instruments like horns, trumpets and trombones can blast you out of your seat just from the vibrations of human lips.

The bottom line is that the closed box loudspeaker, seemingly simple is from an acoustic point of view a very bad idea, and expensive to execute properly. It is highly wasteful of resources. It takes massive expensive motor systems and monstrous amounts of power to execute properly.

In your situation the 12" drivers are doing the majority of the lifting, and I have to say that the 10" drivers are contributing next to nothing to the table. For future reference using different drivers like you have is not a sound acoustic plan.

 

[Stones]

I guess for the price is somewhat operative here.

However, from an engineering standpoint a sealed sub is an awful idea.

The reason being is that a loudspeaker cone is an absolutely atrocious coupler to air. That is why you have the pretty much useless response before Eq. The only advantage of a sealed design is domestic harmony, after that it ALL downhill.

Loudspeakers for good bass reproduction need an acoustic transformer. That mean a pipe, horn or Helmholtz resonator. Of which the former two are the most efficient, but the least conducive to domestic harmony.

The ported enclosure is a Helmholtz resonator. In the operative FR the cone of the driver almost stops still and the bass is efficiently produced via the port. Below F3 the driver quickly decouples from the box.

Specialized pipes, known as transmission lines can be designed that give broader, more efficient low Q support, which is my favored approach.

Horns are highly efficient, but complex and large.

You just have to consider musical instruments. Pipe organs, flutes and woodwinds like the oboes and clarinets can fill concert halls from the vibrations of small reeds or passage of air over a ledge. The most powerful instruments like horns, trumpets and trombones can blast you out of your seat just from the vibrations of human lips.

The bottom line is that the closed box loudspeaker, seemingly simple is from an acoustic point of view a very bad idea, and expensive to execute properly. It is highly wasteful of resources. It takes massive expensive motor systems and monstrous amounts of power to execute properly.

In your situation the 12" drivers are doing the majority of the lifting, and I have to say that the 10" drivers are contributing next to nothing to the table. For future reference using different drivers like you have is not a sound acoustic plan.

In hindsight I’m sure I could have got similar results for less money. But these subs do sound really good just not as efficient as ported options you mentioned . I had to spend $650 on each amp to get acceptable spl levels.
That said I am very happy with the end result after my adjustments to phase. The 10” subs actually make a big difference in REW both in spl and smoothing out bass response . Probably not most cost effective way to go but I already had a amp and boxes for them .
Live and learn .

thanks for all your help