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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => LAB Subwoofer Forum => Topic started by: John Wilson on February 17, 2020, 03:42:07 PM

Title: FBT VHA 118SA-?????
Post by: John Wilson on February 17, 2020, 03:42:07 PM
Does anyone own/use this particular sub-woofer?  Do the published performance numbers seem realistic/achievable?   Thanks for any and all answers.  Click on specifiche in the link. 


http://www.fbt.it/-/horizon-vha-118sa
Title: Re: FBT VHA 118SA-?????
Post by: David Morison on February 17, 2020, 05:51:50 PM
Does anyone own/use this particular sub-woofer?  Do the published performance numbers seem realistic/achievable?   Thanks for any and all answers.  Click on specifiche in the link. 


http://www.fbt.it/-/horizon-vha-118sa

It won't achieve that max SPL, for any decent length of time if fed with a signal covering it's full intended bandwidth.
It might manage it if fed only certain frequencies, but even then, it'd probably exhibit unreasonably high distortion and possibly shorten the driver's useable lifespan in the process.
Title: Re: FBT VHA 118SA-?????
Post by: Jeffrey Knorr - JRKLabs.com on February 18, 2020, 10:48:57 AM
Does anyone own/use this particular sub-woofer?  Do the published performance numbers seem realistic/achievable?   Thanks for any and all answers.  Click on specifiche in the link. 


http://www.fbt.it/-/horizon-vha-118sa

I generally like FBT products but that has to be over rated by at least 6 dB.

Jeff
Title: Re: FBT VHA 118SA-?????
Post by: Chris Grimshaw on February 19, 2020, 11:43:53 AM
https://www.prosoundweb.com/spec-wars-looking-inside-loudspeaker-spl-specifications/

Those SPL ratings are likely a WLS rating (When Lightning Strikes).

Chris
Title: Re: FBT VHA 118SA-?????
Post by: Caleb Dueck on February 19, 2020, 02:13:42 PM
Do the published performance numbers seem realistic/achievable?   Thanks for any and all answers.

Specs that look too good to be true - are.
The lower the product price - the more 'off' the specs typically are. 

Hopefully that 95% answered this and a few hundred other questions all at once :)

To further elaborate - if you outline what SPL and frequency response you truly need, and then compare the true cost of subs/amps required to hit that target - you'll find that more/cheaper gear typically costs more than fewer/better gear, whatever that gear is.  Especially when you factor in the incremental upgrade cycles (IE watching your money walk away many more times than necessary) and the future expansion costs (IE, how much cost to add 5dB, to add 10dB, etc). 
Title: Re: FBT VHA 118SA-?????
Post by: Luke Geis on February 19, 2020, 09:24:39 PM
I don't know, but the spec seems at least half plausible. They say half-space, so the 143 peak spl is +6db of what it would actually be. The amp says it is 5000 watts! That being the case, that means to achieve an actual 137db peak SPL ( 143db minus 6db=137db ) the speaker would have to have a sensitivity of 100db. For subs, a 100db sensitivity isn't too hard to fathom. I think it would realistically produce somewhere between 130db and 134db in the real world. The spec they show is plausible though.
Title: Re: FBT VHA 118SA-?????
Post by: John Wilson on February 21, 2020, 10:21:55 AM
The amp says it is 5000 watts!

The amp is 2500 watts RMS
Title: Re: FBT VHA 118SA-?????
Post by: Luke Geis on February 21, 2020, 04:23:11 PM
5000 watts peak, 2500 RMS, tater tots or potatoes.


If it was still only 2500 watts it would still be within 3db. of stated specs. I still think the numbers are plausible, not probable; as I said, real-world, I would bet on closer to somewhere between 130-134db actual output. Peak, RMS, or however you want to put it.
Title: Re: FBT VHA 118SA-?????
Post by: John Wilson on February 21, 2020, 10:51:27 PM
5000 watts peak, 2500 RMS, tater tots or potatoes.


If it was still only 2500 watts it would still be within 3db. of stated specs. I still think the numbers are plausible, not probable; as I said, real-world, I would bet on closer to somewhere between 130-134db actual output. Peak, RMS, or however you want to put it.

Cool.  Thanks for your input sir.