Compact Power Subs for Stick mains

M

Matt Vivlamore

Senior
Jan 11, 2011
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Southern MD, USA
www.meerkatsound.com
With my Speaker on Stick thread (Link: http://soundforums.net/varsity/8766-speaker-stick-build-large-budget.html) going and being more geared towards Mains... I have settled on purchasing the Fulcrum FA22ac tops in the near future, so now its time to look at subs that would be a good match to the tops and fit my needs. I am trying to sell my SRX/NL4 rig to switch over to a PowerCon Rig at the same time.

For the past 5 or more years I have been using the SRX718s and they are enough on 98% of the gigs which I supply FOH sound. I have grown to love the scalability of having the single 18s, I can bring in 1, 2 or 4 depending on my needs for the show that I am doing; crowd size can range from 75-650 people.

Here is a list of my 'WANTS' and/or 'Must Haves':
- Compact box; think SRX sized.
- Lighter weight; ideally under 100# (single person lift)
- Power Con out (so I can jump power up to the main)
- Pole Mount; M20 is first choice
- 4 wheels on the back
- equivalent or better than the SRX718s/IT8000 combo
- easy on the Power/Amp draw; we ask for 3x 20amp circuits for Audio/Lighting/Band, but sometimes only given 1 Edison outlet.

I would like to have the following, but won't be a deal breaker:
- Network (Cat#)
- AES (digital audio)

I don't care how good it may be, I do NOT want:
- Dual 18s or refrigerator size speakers;
- IEC power plugs; to much risk with plug falling and or pulled out
- tilt back wheels; can't stack anything on top
- future product; must be in production now.


So what is out there and what is worth looking at?
 
Re: Compact Power Subs for Stick mains

List to be updated as new products come out...

Brand - Model
dB Technologies DVA S10DP
dB Technologies DVA S1518N
dB Technologies DVA S1521N
EAW NTS250
Fulcrum TS215ac
JBL VPSB7118DP
JBL VRX918sp
L-acoustics SB15P
Meyer 500-HP
QSC KLA181
RCF NX S21-A
RCF NX S25-A
RCF Sub 8004-AS
RCF Sub 8005-AS
RCF TTS18-A
Turbosound NuQ115B-AN
Turbosound NuQ118B-AN
 
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Re: Compact Power Subs for Stick mains

Hi Matt,

My admittedly biased opinion is that you've made a good choice ;-) I wouldn't normally promote a product on the forum, but I think (hope - Bennett?) in this case it is warranted; the subwoofer "mate" to the FA22ac, TS215ac, was just posted to our website yesterday, so you probably would not know it existed. We've actually sold a number already, but we were waiting to iron out a few details with the caster board and software control before posting it.

http://fulcrum-acoustic.com/assets/pdf/Spec Sheets/Prod Spec, TS215ac v2.pdf

The only deviation from your wish list is that the wheels are on a removable face-mounted caster board.

David Gunness
Fulcrum Acoustic
 
Re: Compact Power Subs for Stick mains

David Gunness said:
Hi Matt,

My admittedly biased opinion is that you've made a good choice ;-) I wouldn't normally promote a product on the forum, but I think (hope - Bennett?) in this case it is warranted; the subwoofer "mate" to the FA22ac, TS215ac, was just posted to our website yesterday, so you probably would not know it existed. We've actually sold a number already, but we were waiting to iron out a few details with the caster board and software control before posting it.

http://fulcrum-acoustic.com/assets/pdf/Spec Sheets/Prod Spec, TS215ac v2.pdf

The only deviation from your wish list is that the wheels are on a removable face-mounted caster board.

David Gunness
Fulcrum Acoustic
Click to expand...

David, Thanks for taking your time. I did see the V1 spec sheet a couple months ago and just been waiting on it to be released. And I heard that the local dealer has one in route for a few people to check out. The fun question, will a TS215ac be able to hold its ground with the FA22ac on larger shows.

Now that you pointed the caster board out, I do see on the spec sheet that the caster board does have latches (good thing).
 
Re: Compact Power Subs for Stick mains

Matt Vivlamore said:
The fun question, will a TS215ac be able to hold its ground with the FA22ac on larger shows.
Click to expand...

In terms of output, I would think of the TS215ac more like a conventional double 18. For a "normal" band mix, it will definitely keep up. If you're doing EDM with the subs cranked up, it would probably take two per side.

Dave
 
Re: Compact Power Subs for Stick mains

David Gunness said:
In terms of output, I would think of the TS215ac more like a conventional double 18. For a "normal" band mix, it will definitely keep up. If you're doing EDM with the subs cranked up, it would probably take two per side.

Dave
Click to expand...

that's good to know... yea no EDM. The band plays anything from Jazz to current Top 40.
 
Re: Compact Power Subs for Stick mains

Given appropriate performance levels, I always prefer matching brands especially when the processing is designed to work together. This is especially true of powered speakers.

In addition, the aesthetics of a matching set is also important in the wedding settings this system will mostly be used for.

Personally, if my budget allowed, I would not be shopping much more.

Sent from my DROID RAZR HD
 
Re: Compact Power Subs for Stick mains

David Gunness said:
In terms of output, I would think of the TS215ac more like a conventional double 18. For a "normal" band mix, it will definitely keep up. If you're doing EDM with the subs cranked up, it would probably take two per side.

Dave
Click to expand...
Dave,

According to the spec sheet, more like a double 21 ;^).
What I don't understand is how a sub with 3 dB less equalized sensitivity ends up having 2 dB more maximum peak SPL using 1000 watts less.

Perhaps the 3000 watt amps you use have a magic 12,000 watt peak output :^).

Nice work on these subs, got to hear a bunch of TS221 at idle while we attempted to tune a system while a plumber worked on a baptismal pool problem..

Art
 

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Re: Compact Power Subs for Stick mains

Art Welter said:
Dave,

According to the spec sheet, more like a double 21 ;^).
What I don't understand is how a sub with 3 dB less equalized sensitivity ends up having 2 dB more maximum peak SPL using 1000 watts less.

Perhaps the 3000 watt amps you use have a magic 12,000 watt peak output :^).

Nice work on these subs, got to hear a bunch of TS221 at idle while we attempted to tune a system while a plumber worked on a baptismal pool problem..

Art
Click to expand...

We determined that too many people were comparing our "continuous" specs with other companies' "peak" specs (like you just did, jokingly I'm sure), so we finally broke down and started adding peak SPL to our spec sheets. <sigh> Can we move on to another topic now?

Dave
 
Re: Compact Power Subs for Stick mains

David Gunness said:
We determined that too many people were comparing our "continuous" specs with other companies' "peak" specs (like you just did, jokingly I'm sure), so we finally broke down and started adding peak SPL to our spec sheets. <sigh> Can we move on to another topic now?
Click to expand...
Dave,

Another topic, like what ever happened to the old Dave I knew who used to put realistic specifications on EV and EAW subs ;^)?
I understand the game of adding ridiculous peak SPL figures for non-powered cabinets, but I don't understand why you would put a peak SPL rating on your TS215 that would require almost 5 times the amplifier power you use in the sub.

Going with your nominal sensitivity of 102 dB (which appears only in the upper range of the TS215's pass band) and 3200 watts of power, we'll keep it simple:
1 watt = 102 dB
10 watts =112 dB
100 watts = 122 dB
1000 watts = 132 dB
2000 watts = 135 dB
4000 watts = 138 dB, oops, amp ran out of power 800 watts ago..
8000 watts = 141 dB
16,000 watts = 144 dB, one dB more than the claimed "143 dB peak" rating.

Same goes for the "Equalized Maximum Peak SPL", which also would require nearly 16,000 watts to achieve, even if we entirely ignore power compression and excursion issues.

OK, now on to the topic of your choice :^).

Art
 

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Re: Compact Power Subs for Stick mains

Could it be by chance that the spec of 3000W of the amp is an RMS spec, and can produce more power for "peak" moments? Thats a big jump though.
 
Re: Compact Power Subs for Stick mains

Art,

as a manufacturer i am totally on Daves side here.

People that know what to look out for in the spec, will have all the data they need.
But majority of customers have no clue about what anything means and they just look at the numbers.

With the competition out there that is putting all kind of magical figures in their spec (sadly some of them are very big and very respected companies that have started this stupid spec war game), you are left with no option but to join the game. Or your product will look inferior on paper.

Thats the reality.

Ill give you a challenge. Try to calculate how Lacoustics came to the SPL figure for the Kara line array. Double 8 inch reflex box of 450W that can do 139db. Yeah right.
 
Re: Compact Power Subs for Stick mains

OK, here we go. Once more into the breach. The reason I hate this is that in the process of explaining how our industry does specs, it appears that I am justifying practices that I actually don't agree with.

One of the reasons I don't like peak SPL specs is that "SPL", at least in textbooks, is defined as the RMS sound pressure (referenced to 2x10-5 pascals). So theoretically, there is no such thing as "peak SPL". OK, maybe that's too pedantic: we could interpret it as "peak sound pressure, expressed in units of SPL". Let's go with that.

The point is that "Peak SPL" as it is treated in the professional loudspeaker industry, is peak pressure, not "highest reading of an SPL meter" (SPL meters only measure RMS; even if there is a peak hold function, it is the "highest rms reading observed", and that includes the selected averaging time). Anyway, peak pressure is calculated using the peak voltage of the amplifier. With non-powered systems, the assumption is that a user will supply an amplifier with twice the power rating of the loudspeaker, and that the peak voltage of the amplifier is 3 dB higher than that, because amplifiers are rated with sine waves. Hence, the peak pressure should be 6 dB higher than the maximum continuous SPL.

Keep in mind that maximum continuous SPL is a survival rating, not a useability rating. Of course what would be more useful is "maximum useable SPL", but that would be signal dependent and would have to be subjectively determined. So we're stuck with a calculated value that serves only as a point of comparison: "This one's red line is 2 dB higher than this one's red line."

As for the TS215ac, here is the math (with one more significant figure than the whole numbers on the spec sheet):
Equalized Sensitivity: 99.2 dB
Maximum Peak Voltage of the Amplifiers: 150 V
"Peak Power" into 2 ohms (actually two channels driving 4 ohms each): 11,250 W
Peak Power, expressed in decibels: 40.5 dB
99.2 dB + 40.5 dB = 139.7 dB, which rounds to 140 dB

Dave
 
Re: Compact Power Subs for Stick mains

David Gunness said:
OK, here we go. Once more into the breach. The reason I hate this is that in the process of explaining how our industry does specs, it appears that I am justifying practices that I actually don't agree with.

Hence, the peak pressure should be 6 dB higher than the maximum continuous SPL.

Keep in mind that maximum continuous SPL is a survival rating, not a useability rating. Of course what would be more useful is "maximum useable SPL", but that would be signal dependent and would have to be subjectively determined.
Click to expand...
Dave,

Thanks for the detailed explanation.

I found the Mackie HD1521 specifications to be useful and accurate, and did not have any subjective problem running music or pink noise to verify the accuracy.
I wish more manufacturers would include the "measured SPL" as well as all the unachievable theoretical values. By the way, if you were responsible for the DSP on the HD1521, congratulations, it sounded (and measured) better than I thought possible.

Art
 

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Re: Compact Power Subs for Stick mains

Someone post a list price for this unit please. I just got a pair of FA22ac and am seriously considering these.
Thanks,
BJ
 
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