# 1x 21" sub Cerwin Vega CVA 121 or 2x 18" sub JBL PRX 618S ?



## AndreaT (Jan 17, 2012)

Dear Folks, I'm going to buy 1 or 2 new subs for my home stereo system.
I would like to have deep bass as in live-event.
For budget issue, I can just buy 1 very big 21" CVA or 2 smaller 18" JBL.

The Cerving Vega CVA 121 is rated -3dB @ 35Hz, while
the JBL PRX 618S is rated -3dB @ 50Hz.

Anybody can tell me if is better to use only 1 sub going down to 35Hz or 2 subs together but capable only to go down to 50Hz?

By physic I would be tend to say that the 18" JBL, even if used paired, cannot match the deep bass of the 21" CVA... but I am not an expert of sound system.

Thanks in advance for your comments.
Kind regards, Andrea.


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## tesseract (Aug 9, 2010)

You can do much better for your money than the Cerwin Vega or JBL. Those woofers are meant for public address sound reinforcement in large rooms, or even outdoors. They give up the lowest frequencies for efficiency. It isn't necessary to make this compromise in your own home.

Consider the internet direct business model, it gives the biggest bang for your buck. Here are a few in your price range, and you can even double them up, two subs is ideal.

Epik Empire

Chase VS-18.1

SVS PB12-NSD

Hsu VTF-15H


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## AndreaT (Jan 17, 2012)

Dear Tesseract, thanks a lot for your highlights!
Regards, Andrea


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## ISLAND1000 (May 2, 2007)

tesseract said:


> You can do much better for your money than the Cerwin Vega or JBL. Those woofers are meant for public address sound reinforcement in large rooms, or even outdoors. They give up the lowest frequencies for efficiency. It isn't necessary to make this compromise in your own home.
> 
> Consider the internet direct business model, it gives the biggest bang for your buck. Here are a few in your price range, and you can even double them up, two subs is ideal.
> 
> ...


Do those manufacturers ship to Italy?


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## tesseract (Aug 9, 2010)

ISLAND1000 said:


> Do those manufacturers ship to Italy?


A quick phone call by Andrea will tell. If not, we'll have to dig a little deeper.


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## DESCypher (Jan 27, 2012)

tesseract said:


> You can do much better for your money than the Cerwin Vega or JBL. Those woofers are meant for public address sound reinforcement in large rooms, or even outdoors. They give up the lowest frequencies for efficiency. It isn't necessary to make this compromise in your own home.
> 
> Consider the internet direct business model, it gives the biggest bang for your buck. Here are a few in your price range, and you can even double them up, two subs is ideal.
> 
> ...


I'm also looking for a sub. Could you order your recommendation in the order of your preference for me? I heard the SVS PB12 is awesome and I'm currently looking to purchase them. I may even buy them tonight before I go to bed.


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## tesseract (Aug 9, 2010)

DESCypher said:


> I'm also looking for a sub. Could you order your recommendation in the order of your preference for me? I heard the SVS PB12 is awesome and I'm currently looking to purchase them. I may even buy them tonight before I go to bed.


Sorry for the delay, I was out of town with limited web access. Understand that all four subs are great values and have received a lot of positive attention. I have only heard the Chase VS-18.1 and the Hsu VTF 15, but will rank and give reasons why. 

1. Performance for the price goes to the VS-18.1.

2. The VTF 15 is very flexible (ported or sealed tuning) and has decent output.

3. The Empire is best suited to sealed rooms which limits flexibility. If your room is sealed, it moves up to tie the #2 ranking. I am partial to sealed subs in sealed rooms.

4. The PB12 is the smallest sub of the group. It is still a good value for the money and was mentioned because of the OP's location in Italy. I wanted to give him several options for overseas shipping as I am unsure who, if any of these, will ship that far.


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## DESCypher (Jan 27, 2012)

Thanks; when you say sealed room you're talking about a HT room that doesn't have an opening to another room at all right? Mine does a little but it's a small space and all doors are closed and enclosed. The HT room is 11'x22 with a slight opening to the side. I saw on the shootout that the Empire did really well next to the 18.1; I think came in third and they said it worked well with placement and was flexible. I don't want anything really big due to the size of the room so the PB12 or the Empire sounds good to me thus far.

Thoughts?


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## tesseract (Aug 9, 2010)

If you can seal the room by closing doors and since size is a concern, I would consider dual small sealed subs. The Empire or the 18.1 will be able to take advantage of the room's gain, therefore digging deeper than a ported sub, which is limited by it's port tuning. After port tune, response drops off rapidly.


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## DESCypher (Jan 27, 2012)

OK yes the room can be sealed. Looks like both are recommended and the price is good. The empire seems to be.the smallest of the two but the 18.1 can do too.


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## DESCypher (Jan 27, 2012)

I also plan on two but one first. I will be putting them in the cornets diagonal if each.


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## tesseract (Aug 9, 2010)

Sounds like a good plan. Dual subs placed at opposite sides of the room near (but not all the way in) the corners works well for many people.

Consider also: Mid wall, left and right sides. Or mid wall front and back.


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## AndreaT (Jan 17, 2012)

Dear Friends, ... most of the listed don't ship to Italy.... well, don't ship abroad US in general.
So, I am going to buy two Behringer B1800D.
Then, I will correct its response using Thuneau Frequency Allocator.
Thanks all for the comments.
Kind regards, Andrea


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## ISLAND1000 (May 2, 2007)

Those will be powerful subs. Good luck with your choice. Please report back after you have them in your system and playing. We need a full report.


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## AndreaT (Jan 17, 2012)

Hi Island1000, this morning I got my new Behringer B1800D-PRO.
I already installed it... but it will take me some time to measure it and tune-up.
I will be back to you by the end of this week.
I will do also a comparison with my current Klipsch RW12.
Let's stay tuned...
Regards, Andrea


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## ISLAND1000 (May 2, 2007)

Excellent! You work fast.
If you can post some pictures of the Behringer subs that would really be good.
Tell more about the Thuneau Frequency Allocator.


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## AndreaT (Jan 17, 2012)

Hi Island1000, 

I completed my installation, replacing the current sub Klipsch RW-12 with the Behringer B1800D-PRO.

Originally I planned to buy and install 2 subs, but... when my wife show the first B1800D-PRO in our living-room... she minaced me to divorce!
So, I had to accept a compromise: just one, not two.

Anyway, the sound pressure is impressive and because I cut it at 50Hz, it doesn't affect significantly the stereo image.

Stated this, let me go to the measurements.

The Behringer B1800D-PRO, as is, is not really capable to operate correctly below 45Hz alone (see response below, taken at 30 cm).
The Klipsch RW-12 is a lot more linear down to 30Hz.









However, the impressive power of the B1800D-PRO (1400W) and the 18" woofer make the equalization an easy and perfect job anyone can do... if you are using the Thuneau Frequency Allocator (see final response below).









Thuneau Frequency Allocator has built-in also a Phase Administrator, so that I could perfectly match the absolute system phase, correcting the sub delay due to its placement about 1 m in the back (respect to the main speakers front: I am using a pair of Martin Logan Sequel II, fully digital x-overed, and having the cells driven by the ARC 100.2 and the woofers by the ML #334).

I don't want to make free advertisment, but I consider correct to notify you that without this Thuneau Frequency Allocator the job would be very hard for me and, because I am not a professional audio-engineer, probably impossible.

Let's stay tuned.
Regards,
Andrea


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## msciandra35 (Aug 23, 2013)

I have a Cerwin Vega cva 121 on the right side of my living room and a Definitive Technology subwoofer on the left side of the living room 
I use 26 foot subwoofer cables it sounds good 

Note that JBL JUST CAME OUT WITH A JBL PRX 718 XLF THAT HAS 1,500 
WHO CARES IF THESE SUBS ARE MADE FOR A CUB OR LARGE PLACES

To be honest I think allot of the subwoofers at many stores are over priced and why by one that is just ok when you could have people over that go holly this is awesome and wow watching a movies is even better. :yikes::T


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## ISLAND1000 (May 2, 2007)

Andrea the graph results looks good. Are you satisfied? Is the wife satisfied? If so, we're good to go even if 10Hz @ 100db isn't a part of the systems reproductive capability.
I'd take the Behringer and the Thuneau over the Klipsch.


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## ISLAND1000 (May 2, 2007)

I think the JBL PRO subs are awesome! They do their jobs exceptionally well.
And it's true, a Cerwin Vega 121 cva paired with a Def Tech sub make a powerful duo.


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## ISLAND1000 (May 2, 2007)

I'm currently using 2 RCF 21s in a sealed box plus a LMS 5400 18 in another sealed box.
My Home Theater gets filled with very good LF stuff.


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## tesseract (Aug 9, 2010)

msciandra35 said:


> I have a Cerwin Vega cva 121 on the right side of my living room and a Definitive Technology subwoofer on the left side of the living room
> I use 26 foot subwoofer cables it sounds good
> 
> Note that JBL JUST CAME OUT WITH A JBL PRX 718 XLF THAT HAS 1,500
> ...


Most club subs don't do well below 40 Hz. One can run into problems trying to EQ below that. If you have the amp power to back the EQ, it can easily drive the sub into xmech. If you do not have the power, clipping occurs.

That said, there are some good pro sound subs that will work fine, and JBL is a good place to look for them.


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