BillFitzmaurice.info

hey guys, I've been trying to track down the charts for the sb850 for a while now. reason is I've got a friend who wants to know "how loud its gonna be" at our show on the 23rd, specifically in comparison to a venue that employs 4x sb850s (in a 1k person room, lincoln theater raleigh).

I was going to do a trace of the chart and draw out a quick 1w/1m graph of six t48s vs 4 sb850, however after tracking down the graph for the sb850 (took a bit of work surprisingly, I find its about 4 db lower than the graph on the product page.... is that because its a whole space measurment and bill adjusted it to be a half space measurement for an apples to apples comparison to a single t48 (which was measured in half space?)?

also, just how many dbs would I add for 4x eaw sb850 anyways? I was just gonna draw a line in the middle of the 4 cab/ 8 cab line on the t48 multiples post int he spl chart section. this isnt a end all be all piece of paper, just a basic representation to get a point across.

The following statements are a summation of spl charts and basic acoustic knowledge, I just want to make clear that I'm not pretending to have personal experience playing at these levels but am doing this as an academic exercise:

One thing you have to keep in mind is that 6 T48's will gain some frequency extension when clustered whereas the SB850 won't. A single T48 seems to be the equal based on the charts he provided and yes afaik every graph that bill posts is normalized to 1w/1m half-space. With 6 of the T48's you'll be getting rather close to the graph of 8 T48's on the SPL charts page. Thus, if I had to guesstimate you'll have 107 dB sensitivity at 30 Hz (up to 112 dB at 45 Hz) (picking a line between 4 and 8 T48's). Also, keep in mind that you can play your T48's as loud as you damn well please as long as you're limiter is properly setup (with sub audible distortion), I'm guessing that the EAW's you'd have to baby/set conservatively because you may or may not have a voltage limit for those cabs. All in all, let's say you push 55 volts through each of them on the highest peaks (which drivers are you using in the T48s?), you'd have around 136 dB at your high pass point (35 hz). Now, that means 118 dB 25 feet away, all clean. AKA, super fricking loud. Of course where the cab is more sensitive you'll get even more spl.

Grain of salt: power compression/power headroom could make the numbers slightly lower.

However, I'd go on a limb and say that the T48 system will have at least double the capacity and 4 times the sound quality at max volume compared to the SB850's.

*edit, i just saw that you did what I did (for the T48's) and looked between the lines.

Quadrupling the cabs gives a theoretical 12 dB, and the only way to calculate max realizable spl would be to know the power handling (and hi-pass value) of the SB850. If they can handle 700 watts per cab than you could add ~28 dB to the trace.

You could use your subjective experience with your 4 T48 (are you using those?) to instill some fear/excitement as to the level of bass.

Just tell them it will be about the same or a little louder....I like to under-promise and over-deliver.

I've been saying a little louder, only trying to get graphs as some intro audio kids asked me for some lol. I eq my titans down above 50hz anyways, so I'd probably pick with the sensitivity for 6 at 50 hz as my *sensitivity value* for the stack.

we have to keep in mind the SB850 takes about 1000 watts (in that regard they would not need to be baby sat that much), and that will make up for the 2 extra cabs I'll be toting.

sine143 wrote:I've been saying a little louder, only trying to get graphs as some intro audio kids asked me for some lol. I eq my titans down above 50hz anyways, so I'd probably pick with the sensitivity for 6 at 50 hz as my *sensitivity value* for the stack.

we have to keep in mind the SB850 takes about 1000 watts (in that regard they would not need to be baby sat that much), and that will make up for the 2 extra cabs I'll be toting.

1000 watts with what hi pass? IME any non-horn I've heard becomes significantly distorted starting at half of its power rating.

MissileCrisis wrote:

sine143 wrote:I've been saying a little louder, only trying to get graphs as some intro audio kids asked me for some lol. I eq my titans down above 50hz anyways, so I'd probably pick with the sensitivity for 6 at 50 hz as my *sensitivity value* for the stack.

we have to keep in mind the SB850 takes about 1000 watts (in that regard they would not need to be baby sat that much), and that will make up for the 2 extra cabs I'll be toting.

1000 watts with what hi pass? IME any non-horn I've heard becomes significantly distorted starting at half of its power rating.

It's 1000 watts per speaker - 2000 watts per cab. Not sure what subs you've heard, but this isn't some piece of junk from Guitar Center - subs like this will take the power - I've had some experience with the JBL 728s - they are loud, clean and will take every bit of 2000 watts per cab. I'd bet these EAWs are no different.

agreed, the sb850s are beefy for sure. only downside is the venue that employs them hates electronic music, and the engineer is VERY liable to cram a compressor down their throat and walk away

That's why I said ime. I haven't had the honor of using real pro gear. I'm sure they are wonderful products. Thank you for correcting me .