RBH Sound 21" Monster 4kwatt Sub First to Meet our Maximus Bassaholic Rating!

[highfigh]

Forget about the 8 Hz fundamental as there is no CD containing it. I don't think that you would find a CD or any other audio medium with such low frequency. There are not many CDs with 32' stop recordings. I have one CD which has some 32' stop passages, especially on track No. 17 (Shostakovich's Credo) :

Amazon.com

Be careful with driving your speakers below their cabinet tuning frequency. Below that point, the drivers are no longer controlled by any air pressure within their box, and it's rather easy to get their cones move beyond their xmax.

You would need good subs such as the Dayton RSS390HF-4s that I'm using in my three front cabinets. Their cabinets are tuned to 16 Hz and I can get an F3 at 20 Hz without any EQ.

Not new to this- Red book audio range is 20Hz-20KHz- not going to play lower or higher. I know signal below the tuning frequency can easily damage them- that's the reason I don' play EDM, movies with stupidly low bass, etc. I use no EQ. If I needed to reproduce special effects realistically and hit the super low frequencies, my system would be designed to do that. It's not- I use it for general audio from TV/movies/video sources and mainly, for music.

As I have posted several times before, I don't need subs. I really don't need to hear such low bass because it annoys me, I heard enough when I worked in car audio and I'm not sure anything would sound as good as I remember my EVs and if I were to find something that good, I wouldn't want to spend that much money. Also, I hear it from two streets away during Summer when the car wash has a crowd. It's not that I see no value in reaching for new lows (sounds like the motto in 'Dodgeball, The Movie') but I don't need it for myself.

 

[Movie2099]

Hello All,

Great to see all the interest regarding our new subwoofer. I have a few comments regarding some of what has been discussed. This subwoofer is not any more dangerous to own or operate than any other high output sub on the market. The subwoofer has a grill option to protect against accidental or purposeful contact with the driver. Yes, the driver is tremendously powerful, but not to the point of causing some type of bass explosion resulting in destruction of the subwoofer that would potentially cause bodily harm or injury as some have insinuated. There have been hundreds of hours of extreme SPL testing performed with this subwoofer while developing the driver and enclosure. Several drivers and a single test enclosure have sustained minor damage in the process, which resulted in further improvements to the driver and enclosure, but sadly nothing as dramatic as what has been discussed. If the subwoofer was capable of explosive destruction, it would make my job incredibly exciting! Just like car crash testing, it is my job to test this product to the point of failure to find out what the subwoofer's limits are. I can definitively tell you, that is not an easy task to perform with this sub using our 4000W+ capable amplifier. I have yet to burn up a voice coil on this driver even when the subwoofer has been continuously pushed over and over again during extreme testing that an end user of the subwoofer would likely never be able to replicate even if they were purposely trying to burn it up. Also, there are no power handling problems at all using neodymium magnets in this open motor structure . Yes, large ceramic magnets used in a motor structure are capable of dissipating more heat, however, because of the enclosed nature of ceramic motor structures (how they cover the voice coil bellow the top plate all the way to the back plate) , they need to be able to dissipate more heat due to being subjected to more heat from the voice coil. The open motor structure our driver uses does not require substantial heat dissipation by the magnets and is ultimately capable of higher sustained voice coil temperatures (thermal power handling).

Why use a sealed design over a vented design for the subwoofer? Read Matt's explanation posted above. He explains it very well. Sealed subs are inherently more effective at producing extreme low frequency (infrasonic) output in reasonably sized enclosures. For those that are interested in a vented version of the 21" sub, we can produce a vented version of this subwoofer which requires a 19 cubic ft enclosure (Fb=16Hz), but is capable of producing 125dB@20Hz and 113dB@16Hz, passing CEA2010 distortion levels. At 12Hz and below the sealed 21-FS/R has more output in a much more reasonably sized 6 cubic ft enclosure.

Regarding how the 21-FS/R performs/sounds, I look forward (like all of you) to reading Gene's opinions in his review. All I can say from my perspective as the engineer behind the product, is this; I have heard a number of very good subwoofer systems from various manufacturers over the 30 years I have worked in the industry, but as of yet, I have never heard/experienced another subwoofer quite like this.

Shane Rich
Technical Director
RBH Sound

The 80 SUB PRO simply the best Subwoofer

The 80 SUB PRO PASSIVE SEALED

www.aia-cinema.com

Ascendo line one! haha. Have you been able to experience this bad boy?

 

[William Lemmerhirt]

@Shane Rich
I am working under the assumption that sealed subs being so much better at deep deep bass as you mentioned is simply due to the size of this particular sub, and other 21-24” ones. I agree that in theory this is true,(due to the shallow roll off)but in practice, with more modest sized sealed subs, even if they can produce spl in the,say, 10hz range it’s well below the threshold of useful output making it moot. One example, I saw a system with four sb1000’s by svs. It was flat to 10hz, but it’s output was in that range was less than 100db. My comparison is obviously apples and oranges as far as size and quality of components.
But generally speaking I believe sealed subs are chock full of compromise, and unless you’re going to use multiple large sealed subs, ported wins the day.
Point being for more casual readers who might read this and think sealed are better, it should be pointed out that there are many more factors involved.

 

[William Lemmerhirt]

And as far as high spl single digit performance? Anyone saying it’s not worth chasing just doesn’t appreciate the “wobble”.

 

[TLS Guy]

And as far as high spl single digit performance? Anyone saying it’s not worth chasing just doesn’t appreciate the “wobble”.

I get plenty of wobble, but I don't need 4KW to do get it! My bass amps barely break a sweat. I work with the laws of physics and don't fight them. That way they work for me and not against me.

 

[William Lemmerhirt]

I get plenty of wobble, but I don't need 4KW to do get it! My bass amps barely break a sweat. I work with the laws of physics and don't fight them. That way they work for me and not against me.

So we agree then?
I’ve never heard this new subwoofer, so I can’t comment on it directly. But we’re in the same camp as far as ported vs sealed. Generally speaking.

 

[TLS Guy]

So we agree then?
I’ve never heard this new subwoofer, so I can’t comment on it directly. But we’re in the same camp as far as ported vs sealed. Generally speaking.

I'm using TLs

 

[William Lemmerhirt]

I'm using TLs

Yes. I know you are.

 

[Goliath]

Would be interesting to compare the Deep Sea Sound Mariana 24SC 24" subwoofer to the RHB model.

 

[jeffca]

This is a product that doesn’t need to exist.

First off, one giant subwoofer is a stupid design decision for any system.

Next is the price: $10K? You can buy a dozen Rythmik servo subs for less and those 12 will destroy this box.

Finally, what does this behemoth weigh? 300lbs?

If you purchase this subwoofer, you are proving that you are a dolt.

 

[Movie2099]

This is a product that doesn’t need to exist.

First off, one giant subwoofer is a stupid design decision for any system.

Next is the price: $10K? You can buy a dozen Rythmik servo subs for less and those 12 will destroy this box.

Finally, what does this behemoth weigh? 300lbs?

If you purchase this subwoofer, you are proving that you are a dolt.

So if I purchase 4 of them, does that make me a 4xDolt? A Super Dolt? Ultra Mega Dolt?

 

[Danzilla31]

This is a product that doesn’t need to exist.

First off, one giant subwoofer is a stupid design decision for any system.

Next is the price: $10K? You can buy a dozen Rythmik servo subs for less and those 12 will destroy this box.

Finally, what does this behemoth weigh? 300lbs?

If you purchase this subwoofer, you are proving that you are a dolt.

Or your proving that your rich

 

[AcuDefTechGuy]

This is a product that doesn’t need to exist.

First off, one giant subwoofer is a stupid design decision for any system.

Next is the price: $10K? You can buy a dozen Rythmik servo subs for less and those 12 will destroy this box.

Finally, what does this behemoth weigh? 300lbs?

If you purchase this subwoofer, you are proving that you are a dolt.

Is that like saying "If you buy a $110K Lexus, you're stupid because you could have gotten a much cheaper vehicle"?

And people who buy $20K+ speakers are also stupid because they should have gotten $2K speakers?

And you think you are smarter than they are since you are calling them stupid?

I mean, personally, I think 21" and 330 LBS is too much for me. But there is a system for everyone.

@Shane Rich, do you have any plans for an 18" Sub (18N-SF/R) that weighs 100 LBS ?

 

[shadyJ]

This is a product that doesn’t need to exist.

First off, one giant subwoofer is a stupid design decision for any system.

Next is the price: $10K? You can buy a dozen Rythmik servo subs for less and those 12 will destroy this box.

Finally, what does this behemoth weigh? 300lbs?

If you purchase this subwoofer, you are proving that you are a dolt.

For the same price as those dozen Rythmik subs, you could buy two dozen BIC subs that will destroy them. Looks like you would be a dolt for buying Rythmik.

 

[Movie2099]

For the same price as those dozen Rythmik subs, you could buy two dozen BIC subs that will destroy them. Looks like you would be a dolt for buying Rythmik.

For the same price as those two Dozen BIC subs you could buy a crap ton of Boones farm wine. Look who would be the dolt for purchasing the BIC subs!

 

[William Lemmerhirt]

For the same price as those two Dozen BIC subs you could by a crap ton of Boones farm wine. Look who would be the dolt for purchasing the BIC subs!

Lmao!

 

[lovinthehd]

Then again some wealthy "audiophiles" spend more on a pair of speaker cables than one of these subs....

 

[Nondemo01]

I don't know why some audiophiles/readers spend so much time attacking product posts, reviews, and previews because of price or "this would destroy that if you bought 100 of them...". 90% of the population use the TV speakers, 8% use a sound bar, and probably 2% actually use a "home theater" system. How about just be happy we can read reviews of these niche products? Jeez.

 

[AMLOR]

Curious as to whether you awarded the Maximus rating or if it's just preliminary? Seems like JL still would need to test, correct?

The Monoprice M-215 shows similar performance and would probably qualify for Maximus too. I hope you all can test both. I think I remember reading that JL didn't want to deal with the size of these mega-subs. I'm particularly interested to know which one performs better in terms of distortion. I'm thinking that the smaller pair of 15" diaphragms is likely to distort less than the single carbon fiber 21"?

 

[gene]

This is a product that doesn’t need to exist.

First off, one giant subwoofer is a stupid design decision for any system.

Next is the price: $10K? You can buy a dozen Rythmik servo subs for less and those 12 will destroy this box.

Finally, what does this behemoth weigh? 300lbs?

If you purchase this subwoofer, you are proving that you are a dolt.

You gotta be a dolt if you don’t go the BIC option.