SRX718 to 'what powered/active sub?'

[Matt Vivlamore]

Re: SRX718 to 'what powered/active sub?'

They are essentially the same box. Hence my comment that it is not an upgrade.

I don't need the "performance upgrade"... The "upgrade" in this move is me being able to lose an amp rack and add vesitility to my rigs.

I just need 4 subs that are equal to 4 SRX718s, and I'm pretty stuck at having the PowerCon plug to match the monitors.

 

[Robert Kenton]

Re: SRX718 to 'what powered/active sub?'

According to JBL's spec sheet, the VRX918sp/918s is measured in whole space. Probably because it is flyable. That's just my best guess lol.

sound wise, probably no difference than Matt's set up with Itech amps depending on how well they are filtered and limited. Not doubting Matt's ability to program his amps either. Lol

the SP subs sound great to my aging ears. Not to much out there in its size, weight and cost. Most of the other boxes cost quite a bit more. RCF, DB Technologies and EAW just to name a few.

 

[Art Welter]

Re: SRX718 to 'what powered/active sub?'

I believe this has been discussed before also: JBL rated these in whole space for some reason. They are very good subs for the money, I don't really care what the specs say.

The 718 and 728 are rated in half space.
The 130 dB spec would be at 3200 watts assuming no power compression.
Assuming the VRX918 amp can deliver 1500 watts, and the speaker it uses is similar sensitivity to the 2268 used in the 718, the difference should not be much if the 718 was also powered with a 1500 watt peak amp.

 

[Matt Vivlamore]

Re: SRX718 to 'what powered/active sub?'

I have the Itech RMS limiters set at 800 watts at 8 ohms, per Crown/Harman presets.

 

[Sean Zurbrick]

Re: SRX718 to 'what powered/active sub?'

If you don't need to fly it, there's not really a reason to spend that much more on the 918. For what you've stated your justifications are, the 618S-XLF is perfect, IMO. It's low, it's loud, it's light, it's relatively compact for the performance, and it has the same badge as your tops. You lose an amp rack and get the benefits of DSP.

 

[Matt Vivlamore]

Re: SRX718 to 'what powered/active sub?'

If you don't need to fly it, there's not really a reason to spend that much more on the 918. For what you've stated your justifications are, the 618S-XLF is perfect, IMO. It's low, it's loud, it's light, it's relatively compact for the performance, and it has the same badge as your tops. You lose an amp rack and get the benefits of DSP.

The 618S-XLF has IEC plug and IEC plugs don't mate with PowerCon (wirelooms are built because of monitor set-up).

 

[Sean Zurbrick]

Re: SRX718 to 'what powered/active sub?'

The 618S-XLF has IEC plug and IEC plugs don't mate with PowerCon (wirelooms are built because of monitor set-up).

You can make these easily. I had the same issues with my RCF subs (had Poercon in and out) and RCF tops (IEC). I just chopped off the plug of the IEC and put a gray powercon connector on it. I also lashed the XLR cable to it to make a little snake to connect the tops to the subs. I've been using this for the past 5 yrs.

I wouldn't let the power connector dictate the subs you choose. That said, if you can spend more and don't mind a somewhat boutique brand, at least here in the states, both RCF and FBT have some very nice powered subs. It still contend JBL's seemingly make the most sense.

 

[Matt Vivlamore]

Re: SRX718 to 'what powered/active sub?'

You can make these easily. I had the same issues with my RCF subs (had Poercon in and out) and RCF tops (IEC). I just chopped off the plug of the IEC and put a gray powercon connector on it. I also lashed the XLR cable to it to make a little snake to connect the tops to the subs. I've been using this for the past 5 yrs.

I wouldn't let the power connector dictate the subs you choose. That said, if you can spend more and don't mind a somewhat boutique brand, at least here in the states, both RCF and FBT have some very nice powered subs. It still contend JBL's seemingly make the most sense.

It was easy for you, since your sub had a PowerCon out.

For me, it’s more complicated/cumbersome since the looms have XLR/PowerCon combined. After the Loom, I would need some sort of PowerCon splitter/quad box ($100-150) and then drop 2 IEC cables into the Quad.

 

[Spenser Hamilton]

Re: SRX718 to 'what powered/active sub?'

It was easy for you, since your sub had a PowerCon out.

For me, it’s more complicated/cumbersome since the looms have XLR/PowerCon combined. After the Loom, I would need some sort of PowerCon splitter/quad box ($100-150) and then drop 2 IEC cables into the Quad.

Why can't you remove the power con and install a single 20A edison in it's place? When your running one sub per side, just use a single IEC cable to the sub, when you are running two or more per side, have a short duplex or quad box on hand.

Unless I'm missing something...

 

[Sean Zurbrick]

Re: SRX718 to 'what powered/active sub?'

Just remove the powercon and replace with an IEC like THIS for $20 each. Both types use tension and strain relief to hold the wires on so you'll likely not have to cut or strip the cable at all. You just need a screwdriver and the knowledge of what wire goes where.

 

[Steve Hurt]

Re: SRX718 to 'what powered/active sub?'

The 718 and 728 are rated in half space.

You superimposed the 2268h specs over a JBL SRX718s spec sheet

The graph that is in half space is a 2268h driver in a 8 cu ft sealed enclosure

The 718 is not a sealed box.

 

[Steve Hurt]

Re: SRX718 to 'what powered/active sub?'

The 718 and 728 are rated in half space.

You superimposed the 2268h specs over a JBL SRX718s spec sheet

The graph that is in half space is a 2268h driver in a 8 cu ft sealed enclosure

The 718 is not a sealed box.

 

[Phil Lewandowski]

Re: SRX718 to 'what powered/active sub?'

Unfortunately I got rid of my Growlers too soon as I was planning to directly measure (again) the SRX718 and Growler to hopefully put the "half-space/whole-space" thing to rest. When I did directly measure them back doing the distortion tests a couple years back with the same input voltage I got nearly identical sensitivities, which I took to mean either the SRX718 graph wasn't published in 1/2 space or the Growler sensitivity was a little lower than published (Which I didn't think was the case). I really wanted to send an identical signal through Smaart to them and measure them both one after the other without changing anything and see what Smaart came out with.

All I can say is the SRX718's move a lot of air for their size and are still the best small value sub I've come across. For 90% of the weddings and bar gigs I do 2 of them stacked to one side is plenty with high energy top 40 dance music they do. (And adding a 3rd has covered all but 2 gigs in 4 years.)

It does seem like this was settled above, but the VRX918 is the same sub as the SRX718, just powered. (JBL said that the only difference in the driver was that the 918 has a dual VC instead of a single to suit the power amp module better.)


Take Care,
Phil

 

[Art Welter]

Re: SRX718 to 'what powered/active sub?'

You superimposed the 2268h specs over a JBL SRX718s spec sheet

The graph that is in half space is a 2268h driver in a 8 cu ft sealed enclosure

The 718 is not a sealed box.

Steve,
You are correct, the SRX718 is a ported cabinet, which is why it starts rolling off from it's 95 dB sensitivity at 50 Hz, while the sealed cabinet using the same transducer starts it's less rapid rolloff at around 70 Hz.
The upper sensitivity is the same for either cabinet, the reason I posted the comparison proving the SRX 718 spec sheet is measured in half space (cabinet on the ground as subs are usually used) rather than free space (non-riggable cabinet suspended in the air).

In the half space comparison below of a Lab 2x12

http://soundforums.net/diy-audio/134-free-sub-plan-dual-lab12-front-loaded-welter-systems.html

to a JBL SRX728, which is rated 98 dB sensitivity, note that the 2x12" is within 3 dB of the output at 40 Hz, and 7 dB less at 80 Hz. The 2x12" corresponds well to the Eminence Bass box Pro simulation, which shows the sensitivity of the 2x12" enclosure at around 94-95 dB. The Lab 12 raw driver sensitivity is only 89.2 dB.

Both cabinets used exactly the same pink noise signal through the same BW24 filter set to 25 and 125 Hz, microphone was on the ground at two meters.
The JBL sensitivity is obviously measured in half space, or one would have to conclude my ported cabinet somehow is another 6 dB more sensitive than Eminence says it could be.
Putting the same transducers in a tapped horn twice the size of the ported cabinet does gain 6 dB sensitivity, but that is another story...

Art

 

[Matt Vivlamore]

Re: SRX718 to 'what powered/active sub?'

Why can't you remove the power con and install a single 20A edison in it's place? When your running one sub per side, just use a single IEC cable to the sub, when you are running two or more per side, have a short duplex or quad box on hand.

Unless I'm missing something...

Just remove the powercon and replace with an IEC like THIS for $20 each. Both types use tension and strain relief to hold the wires on so you'll likely not have to cut or strip the cable at all. You just need a screwdriver and the knowledge of what wire goes where.

That is pointless; I would need to carry twice the number of cables or a box full of connectors and swap out.

Yes, I am being stubborn because I ABSOLUTELY HATE IEC connections and I avoid them as often as I can.

 

[Robert Kenton]

Re: SRX718 to 'what powered/active sub?'

That is pointless; I would need to carry twice the number of cables or a box full of connectors and swap out.

Yes, I am being stubborn because I ABSOLUTELY HATE IEC connections and I avoid them as often as I can.

Matt, just wondering where the RCF HD boxes fit in with your rig? I was kinda surprised when I saw that you bought because of this above lol.

 

[Sean Zurbrick]

Re: SRX718 to 'what powered/active sub?'

Hey, I'm just pointing out what's seemingly practical from a financial, performance and brand perspective. If your disdain for IEC connectors means you're throwing out any box that has them, that's fine. Generally speaking you're now looking at more expensive and harder to find and have serviced options. I think the full line of FBT and RCF subs use Powercon, but am not certain. Subs from both brands that I own use them.

Another brand to take a look at would be KV2.

 

[Spenser Hamilton]

Re: SRX718 to 'what powered/active sub?'

That is pointless; I would need to carry twice the number of cables or a box full of connectors and swap out.

Yes, I am being stubborn because I ABSOLUTELY HATE IEC connections and I avoid them as often as I can.

Sorry to have touched a sore spot Matt :lol: I kid.

I don't think it's that bad of a solution, I see a lot of rigs come through our theatre. One thing I've noticed is that any time I see a powered box with Powercon, they are usually converting to IEC as soon as possible.

 

[Matt Vivlamore]

Re: SRX718 to 'what powered/active sub?'

Matt, just wondering where the RCF HD boxes fit in with your rig? I was kinda surprised when I saw that you bought because of this above lol.

Since, I am looking at the single driver sub boxes with PowerCon plugs, they seem to have a PowerCon out which will allow me to loop out the power and into the top. I am not looking to drop a quad behind each stack to plug all the speakers into; I want to be able to loop power up from the subs into the mains with the XLR send is attached.

I haven’t seen an IEC powered sub with an Edison out.

Well, I was going to buy a pair of the DVX D12 for mains, but couldn't swing the money at the moment. So I ended up buying the RCF HD12A as small box speaker to go with the Speaker over Sub/Stick rigs, for the price I paid I couldn't beat it deal. Also, I have built PowerCon-Gray to Edison Outlet jumpers for this to work.

 

[Jay Barracato]

Matt

The 18 inch in jbls VP line is also power con. I am not sure how they price out.