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Discussion Starter · #1 ·
Summer project, I am thinking about building 2 devastators fatboy v1

I have PMes a few people about the drivers,
I understand the Eminence driver is the better overall driver, BUT at what point ?

1000w
1500w
2000w
Or are they so close ill never tell the difference

If anyone has any experience with both please share your feedback.

Being in Canada the BC 21DS115 is 750$ CND funds - back in stock in 4 weeks

The Eminence is 1k CND FUNDS - no stock and no eta .

I am thinking of using 2 crown xls 2502 bridged ,

Jeremy
 

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Summer project, I am thinking about building 2 devastators fatboy v1

I have PMes a few people about the drivers,
I understand the Eminence driver is the better overall driver, BUT at what point ?

1000w
1500w
2000w
Or are they so close ill never tell the difference

If anyone has any experience with both please share your feedback.

Being in Canada the BC 21DS115 is 750$ CND funds - back in stock in 4 weeks

The Eminence is 1k CND FUNDS - no stock and no eta .

I am thinking of using 2 crown xls 2502 bridged ,

Jeremy
Have you checked with kevin at GSGAD? They do offer better pricing than advertised MSRP if you reach out to them.

I just bought two NSWs and just got two 2502s to power them in a finalizer v4.

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Summer project, I am thinking about building 2 devastators fatboy v1

I have PMes a few people about the drivers,
I understand the Eminence driver is the better overall driver, BUT at what point ?

1000w
1500w
2000w
Or are they so close ill never tell the difference
Are you trying to choose between drivers on power handling alone?:cautious: Sims/models, which take application/enclosure into account, would be the proper method to choose between drivers IMHO.
 

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The NSW is better in every way over the DS, it is also more expensive.


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My guess is the low end at about 2000W is where you are are going to benefit from the NSW the most. I highly recommend @Red Five 's HornResp devastator tutorial so you can do the sims yourself and you can compare the curves of the different devastator designs pretty easily if so desired. Looked a little intimidating to me at first but it's actually pretty straight forward.

 

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Discussion Starter · #6 ·
My guess is the low end at about 2000W is where you are are going to benefit from the NSW the most. I highly recommend @Red Five 's HornResp devastator tutorial so you can do the sims yourself and you can compare the curves of the different devastator designs pretty easily if so desired. Looked a little intimidating to me at first but it's actually pretty straight forward.

Thank you I will do it
Are you trying to choose between drivers on power handling alone?:cautious: Sims/models, which take application/enclosure into account, would be the proper method to choose between drivers IMHO.
No not just power handling, I will do the Sims and compare,

Looking for feed back on the drivers and peoples experience,

One conversation I had , now this was a lavoce 21 vs Eminence 21, they felt it took 2000w for the Eminence to start pulling ahead,
 

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One conversation I had , now this was a lavoce 21 vs Eminence 21, they felt it took 2000w for the Eminence to start pulling ahead,
Yes, but what enclosure was being used?
The Eminence 21 would no doubt be the driver of choice if you look to achieve the the most SPL in the ULF region. But not because of power handling alone, it has more xmax as well.
Let's say you built an enclosure which requires only 1000w to reach the Eminence 21's xmax limit, then what would there be to gain by feeding it 2000w?
 

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Discussion Starter · #8 ·
Yes, but what enclosure was being used?
The Eminence 21 would no doubt be the driver of choice if you look to achieve the the most SPL in the ULF region. But not because of power handling alone, it has more xmax as well.
Let's say you built an enclosure which requires only 1000w to reach the Eminence 21's xmax limit, then what would there be to gain by feeding it 2000w?
Devastator fatboy v1 x2 19hz tune, looking at to build is summer,

The fatboy v1 can work with both BC or Eminence,

There's 1000w & 2000w model with the Eminence,
 

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I understand the Eminence driver is the better overall driver, BUT at what point ?

1000w
1500w
2000w
Or are they so close ill never tell the difference

If anyone has any experience with both please share your feedback.
I don't have experience with either driver, but I can tell you that box models are usually pretty accurate.

The "why" is fairly complicated actually, and the simulators factor a lot of that stuff in. But in simpleton terms it basically comes down to:
cone area, driver efficiency, power handling, and xmax and xmech.
(and applied-power)

Generically speaking, for frequencies below 40hz they will mostly be limited by excursion and less by power. (Power is required to have excursion though...)
Above 40hz it will mostly be limited by power-handling, drive level and amplifier beefiness. (The more, the better in terms of SPL.)

One thing that simulators don't model is distortion and heat.
Distortion increases will both excursion and heat.
Heat and excursion are caused by power.
There is also mechanical distortion from moving parts (the magnetic force rapidly approaches zero once the coil leave the gap, while the surround and spider become increasingly more taught, a bad combo in terms of sound quality.) It happens to just about all drivers.

The solution to the power/heat/excursion problem is to add more cones/boxes/amps. This distributes the power and heat and excursion over more components, reducing stress/strain.

Generically speaking, you can consider a 2x increase in power to increase the heat 4-8x, and the excursion to increase by 1.4x. Pushed too far and something will bottom and/or release the magic smoke, burnt slinky and deformed cones are the result.

The best way to "get louder" is to add.
A doubling is 6db louder, 3db from doubling the total-system power and 3db for "free" by adding twice as many cones (assumes box-space also).

The worst way to "get louder" is to buy a more expensive driver and give it even-more power. That's usually a losing battle. The only exception is if you are constrained by space or constrained to a single driver and amp, or if you just want to use the best drivers and/or possibly add more of them down the road.

If you want lots of 1-30hz the best option is generally a 24-36inch subwoofer with as much xmax as you can get your hands on (and multiples of those.)
If you want lots of 30-300hz, then stick to pro-woofers.

The NSW-21 is a a good all-around-er, it has decent excursion, power-handling, coil size and cone size (and box size.)
Nothing will really beat it above 30hz and only the largest woofers on the planet would beat it in the infrasonic region (assuming an equal number of drivers and cost no-object).

However if you compare say my 16 PA-460's, even quad NSW-21's would be strained to out-mid it for the same price point of $1400. That's just the law of big numbers at play. 16kW burst 8kW RMS and 98db/w/m x16 into 4071sq-inches of cone area is serious-business no matter how it's computed... ;) But yes it isn't a 1-20hz monster. (That's what the array of beefier ULF woofers are for... ;)) But yes I'll admit "not everyone" wants 32 subwoofers and 100kW in their room either.

Just know that there are many ways to skin this SQ/SPL cat, there is no "right or wrong" answer.
Everyone has different aesthetical tastes, objectives, space and budget...
If every human or system was the same, life would be boring!
 

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In real world use the B&C and Eminence are pretty close. The eminence is a better driver but if you're doing your designs right, you may never see it. What I mean by that is leave margin in the table on your designs, and it's NEVER bad to have more cone area, coils, and box volume. This is such an understated thing. It's so important. You can have a MUCH lower quality driver, and if you have enough of them, the high dollar drivers won't touch them. In this regard subwoofers are simple and easy. I feel like most people on this forum would do well do follow BTH's model (well, part of it anyway) and just use 8 PA460's per enclosure. Have 2-4 of them, DSP the snot out of them, and never look back. For me? I'm going with 8 LaVoces and using them with PR's. It's my best compromise on room size, output, distortion, cone area, etc. etc.
 

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If they could port the PA-460's to 15-25hz they might "do okay" as the only subwoofer type in the room.

However if you don't have the space for that, the NSW-21's would be the better deal because it would be more compact and you'd get more 15-30hz out of the system due to the much much higher xmech/xmax. Depending on your needs/demands of both mid-bass and infrasonics, you might even be able "get away" without needing any ULF drivers at all.

With only 8 PA-460's porteds, you might still be left wanting more 15-25hz... (Depends on the person/room. Hard to say with certainty!)

Some members here have 12 FTW-21's or 32 SI-18's and STILL want more ULF. The only saying is "never enough infrasonics". But with mid-bass "most people" would find say 130db a reasonable amount (which 4 NSW-21's or 8 PA-460's should be able hit). i.e. the threshold of ear-damage\pain above 40hz.

Where as in the 1-20hz region the threshold of ear-damage/pain is closer to 150-170db.

(At the golden seat of course, i.e. not @ 1m only... Unless it's placed nearfield that is!)

If you look at data-bass for example the pro 21's modelled there have almost the same ULF output under 10% THD as the LMS-18 has.

The SHS-24 or SAB-24 would have substantially more ULF than either because those are 50mm+ xmax ony-way drivers (with a 24inch diameter), even the lesser SI-24 would be more ULF than either.
The right tool for the right job. The pro-woofers are chest-kick kings and the ULF drivers are earthquake simulator kings.

A system should really have both to have the best of both worlds. Although with enough of either you could eventually achieve the goal (just less efficiently and more expensively)

I have no desire for more mid or chest-kick than what 16 PA-460's provide because it can drown out a pair of 108/db/w/m SEOS's (even when given driven at full 120w rms power above 1khz), at any distance. So there is no possible/reasonble way to use their full output without it sounding absurd. They just coast along even at +130db @ 10ft. They also hide behind my LR's nicely, consuming only 4sqft of floor space in each front corner.
It worked for me, but it might not work in other peoples room.
The WAF factor of my system like: negative infinity though. (WAF's + 194db continuous, don't mix... hehe! ;))

Other people may need to have the more-compact NSW-21 type solution. Ya know, before she complains of the many-multiple black fridge-sized boxes in the house\room\living space etc etc etc.
The thermal heat will kick in sooner, but that's unlikely to be encountered, unless you are an extreme-basshead like me. I happen to listen to music for 4-8hours continuous at full volume, not everyone needs that much coil-area or total-summed efficiency to take all the heat away. Most people are... "more reasonable"... hehe! ;)
 

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Discussion Starter · #13 ·
I reached out to John ( Redfive ) and asked him the question,

Eminence vs BC , 21" Drivers in the fatboy v1
This is our conversation
 

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Discussion Starter · #14 ·
Eminence vs BC
1000W
1500W
2000W

Max SPL graphs at 2000 watts might make the most sense....

-John
 

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Discussion Starter · #16 ·
21DS115-4 2000 watts max excursion 20mm


3119709


The DS motor is really driving hard into the resonance.
 

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Discussion Starter · #17 ·
They look the same, maybe the DS has a little bump at port tune , might be working a little harder but that would just be burst 2000w
 

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Discussion Starter · #18 ·
Considering the price delta, the NSW is a hard sell here. The DS is not hitting 20mm, so it should not be breaking up too hard yet. The NSW is guaranteed clean at that power, but how often are you going to hit that power without marital issues?

-John
 

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Discussion Starter · #19 ·
Big thanks to John again for all the help,

For me and what I will be doing there is no need to spend extra on the Eminence driver,
 

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Too bad you aren't in the US. Parts Express has an open box DS115 for $479. I don't think PE accepts woofers in return that have been mounted so it should be a safe buy.

 
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