Shootout: KF650e vs DX1565

Silas Pradetto

Graduate Student
Well this was fun, and loud. Since I acquired a pile of KF650s and own a pile of Fulcrum DX1565s, I figured I'd do a quick shootout to see how loud they got.

First up, we have the old school KF650e with a single 15" woofer, a 10" horn loaded mid, and a 2" horn loaded HF. All pretty standard components. As seen in the other thread, I was biamping the speaker undergoing testing with a Crown IT5000HD with my custom IIR presets and the recommended high pass of 80Hz. The KF650 weighs about 150 pounds and is not pole mountable, making it relatively difficult to deploy, especially as one person.

Second up, we have the Fulcrum DX1565. This is the new kid on the block, with a 15" woofer and a 15" coax driver with 1.5" exit HF horn. The Fulcrums were running the provided FIR presets, also with an 80Hz high-pass. The DX15 series weighs about 90 pounds and is pole mountable, meaning I can do a show myself without a problem. I routinely stack and unstack these on stands with no help.

First impressions: playing a variety of music switching back and forth quickly, the KF650 sounded much more mid-heavy than the DX. By mid-heavy I'm talking in the 600-1k range. With the KF I was not really able to EQ out the sound. The overall SPL from the boxes sounded similar when driven with the same signal and the output meters being in the same position on the amps - so the sensitivity is pretty similar, and so is the power handling. Both can handle the IT5000HD @ clip without any trouble, at least with 6dB crest factor Smaart-generated pink noise.

Controls: to try to get things to be consistent during measurements, I placed an Audix TM1 equidistant from each box, with both boxes situated side-by-side pointed at the mic. Both boxes remained plugged into their respective amps during testing as to not interfere with the other speaker's measurements (an unplugged speaker can affect a speaker next to it in funny ways). My measurement environment was not great, it was just in the driveway outside my shop area. There were some reflections from a nearby trailer, but nothing too bad, at least not that would affect these results too much. The mic was placed about 25 feet from the stack and the mains were sitting on top of one of my SRX728S subs. See pictures for placement specifics:
2012-07-04_14-52-48_932.jpg2012-07-04_14-53-03_567.jpg2012-07-04_14-53-14_290.jpg

So, to do a max output measurement, I had to see how loud each box would go when playing pink noise. The IT5000HD might have been slightly underpowered for this, as neither box hit limit before the amp clipped. Here is the picture of both boxes relating their maximum outputs:
kf650 vs dx1565 MAX SPL with IT5000HD.jpg
I bet you can guess which box is which - before each measurement was taken, I ran 'AutoSm' to get things as close as possible. The KF650e has a TON of phase wrap versus the DX1565. The KF650e seemed to have a tad bit more output above about 3k, but that may have been a result of EQ choices in their DSP settings. The DX1565 has a ton more output below 200Hz due to the double 15s going all the way down.

Here are pictures of the amps when they were at their maximum outputs. Due to the nature of pink noise, it's a dynamic stimulus, and the instant I took these screenshots the DX1565 (right amp) was reading a higher level than the KF650e (left amp). Both measurements, though, were taken just as the amp hit clip, as indicated by the big red clip light at the top:
dx1565 at clip.jpgkf650 at clip.jpg

Thoughts:
The KF650 is 60 pounds heavier and not pole-mountable, but is just about as loud. With a larger amplifier, the difference between the boxes may have been more apparent, but on paper and in reality, the main portion of the outputs of these cabinets are within about 2dB of each other. The Fulcrum box definitely wins below 200Hz, and blows away the KF650 when using the Full Range presets, which run both boxes down to 45Hz or so.

Also, the sound quality difference between the two is staggering. Even though the magnitude traces are pretty close, they sound so different. If the KF650 was running the Gunness FIR presets I bet it would sound vastly better.

Overall, I like both boxes, but I'm sticking to my DX1565s for now.
 
Re: Shootout: KF650e vs DX1565

It's great that you're able to find a winning solution that excels, AND fits your needs personally. I find too often that people settle on things like this, or just trudge along using what they've always used when they have many other, and better, options out there.

Just because I don't know, what's the price point difference between the two?
 
Re: Shootout: KF650e vs DX1565

My experience with KF650s is that the horns outrun the cones with a single box, but when you have multiple boxes this effect is reduced thanks to coupling between the boxes. But that doesn't really matter since I don't think I've ever seen a KF650 used by itself. I don't suppose you compared 2 boxes per side?
 
Re: Shootout: KF650e vs DX1565

My experience with KF650s is that the horns outrun the cones with a single box, but when you have multiple boxes this effect is reduced thanks to coupling between the boxes. But that doesn't really matter since I don't think I've ever seen a KF650 used by itself. I don't suppose you compared 2 boxes per side?

No need. Of course, when running multiple boxes of anything, the LF is usually not directional enough to be restricted to the box's rated coverage pattern, meaning it definitely will couple with nearby boxes, to a point. In the case of the 650, I agree, that running multiple boxes would increase output below 200Hz. In this particular measurement case, however, I could have simply added EQ to fix that, since there was plenty of headroom available on channel 1 of the amp. My goal was to measure with stock/factory presets, not something that I created or modified.
 
Re: Shootout: KF650e vs DX1565

How did you determine "maximum output"? was it the point of power compression or sound quality or distortion or some other way?

Hi Ivan, this is a very good question and I didn't really answer it in my OP. In this particular case, maximum output is more closely related to 'maximum overall sensitivity'. Here's why:

The amplifiers used to power these boxes for this demo provide 1250 watts into an 8 ohm nominal load. I did not impedance sweep the boxes to determine exactly how much power was being used under the measurement conditions. The thought process that went into these measurements was like this - both the LF sides of things were rated at less continuous wattage than the amplifier can deliver. The Fulcrum is rated 700W and the KF650 rated 1000W on the LF side. Both the MF/HF sides are rated less than the amplifier output as well - Fulcrum being 350W and the KF650 being 400W. I set the limiters on the amp to these values, based on the voltage formula. When taking the measurements, my goal was to measure in the same way that Fulcrum does, "increasing output until any one subsection of the box is driven to full rated power." However, the amp didn't provide enough voltage/wattage to actually comply with this requirement, meaning the amp clipped before any subsection was driven to full rated power. With a 6dB crest factor pink noise stimulus, I'd need 6dB above rated power of each passband to get to this point, so I'd need an amp capable of 2800 or 4000 watts at 8 ohms on the LF, and 1400 or 1600 watts at 8 ohms for the HF sides of things. In this case I only had 1250 available, so I pretty much expected the amp to run out of headroom first.

The difference between 1250 and 1600 or 1400 watts is very minimal - about 1dB. Since both boxes ran out of headroom on their MF/HF bands far before the LF bands, just due to the way 'flat' needs to be EQ'd, the fact that the LF sections had a ton of headroom didn't really matter. So both boxes were driven to within 1dB of their maximum output when the amp clipped.

Hopefully that answers the question - when the boxes were driven to amp clipping with pink noise, things still sounded good; nothing sounded like it would explode. I was wearing ear muffs so my ear certainly wasn't distorting. Under an actual music program things may have ended up differently, but the measurements I took matched well with the paper specs of both boxes. Fulcrum says 131dB continuous for the DX1565, and EAW claims 139dB peak for the MF of the 650, so removing 6dB for their continuous spec, they'd be 131 vs 133dB. Seems to match up pretty well.
 
Re: Shootout: KF650e vs DX1565

Just because I don't know, what's the price point difference between the two?

Hey John, the KF650e is no longer available new, but used prices seem to be in the $1500 per box range. The Fulcrum DX1565 portable version runs considerably more, at about $3400 MSRP. Plus for the Fulcrum you need a processor or amp capable of FIR/Level 1 settings to make it worthwhile. Once outfitted with IT5000HD amps, my rig is running more than $5000 per box.
 
Re: Shootout: KF650e vs DX1565

Hi Ivan, this is a very good question and I didn't really answer it in my OP. In this particular case, maximum output is more closely related to 'maximum overall sensitivity'. Here's why:

.

Thanks for saying how you did it. Very often "how loud" a loduspeaker is a highly debated item. Whenever any two devices (be it loudspeakers-amps mics etc) are compared-there will always be "arm chair" people who are quick to jump on and state what the poster did "wrong". HOWEVER-THEY were not there-and it is real easy to "second guess" what another person did. Anybody who has ever done this realizes it is not as easy as it may seem. The more "even" the test can be-the more meaningful the results.

There is "how loud" a loudspeaker can possibly make some sort of "noise", and then there is how loud a loudspeaker can get-and still sound good or at least listenable.

These are numbers/specs that are often hard to come by-at least accurately or comparitively.

It is good to see that some thought went into the whole process. It brings a lot more validity to the comparisom.

And having measurements under the same conditions is also a good thing. While they may not directly compare to other measurements-they are comparable to the particular loudspeakers in the comparisom.
 
Re: Shootout: KF650e vs DX1565

Also, the sound quality difference between the two is staggering. Even though the magnitude traces are pretty close, they sound so different. If the KF650 was running the Gunness FIR presets I bet it would sound vastly better.

Overall, I like both boxes, but I'm sticking to my DX1565s for now.

Hey Silas,
Yep, as a former 650 owner, the difference between them before and after the Gunness Focusing is very substantial. When I added the 8800 to my rig it took them from good to great. I can remember back as a kid when I was just getting started in learning about live sound, I thought that you could just match EQ and boxes would sound roughly the same. I quickly learned otherwise (but I wish that were true, it would make things a lot easier and cheaper!...... :)

For strong output and sound quality, I'm not sure that there is a better bang for the buck than a used KF650 rig with the 8800 processor. The Fulcrum stuff is outstanding pro gear (I may be mixing a show on some DX's soon!) but as you mention, around 5K per box once you consider processing.

I miss the 650 rig, but don't miss lugging those boxes by myself on 1 man shows, I can do without a hernia.

Nice review. The Fulcrum stuff is serious kit.
 
Re: Shootout: KF650e vs DX1565

A triamped 650 has a good bit more get up and go too. A UX8800 driven rig with Crown MA power is pretty serious!



Evan

+1 to Evans and Jeff’s comments.

I also don’t think you are making a useful comparison – the 650e is an old box. It could be used full range but it was really a mid/hi cabinet needing a sub to take advantage of its output capabilities.

The newer “Gunness Focused” 650z run tri-amped, crossed over to a good double 18 at about 100 – 120 Hz will make a lot of good quality noise, and throw a resonable distance.

The compromises in the DX1565 design are different – it will make more bass but will not go as loud used as a mid/high cabinet compared to a tri amped 650z.

So it depends on what you need...
 
Re: Shootout: KF650e vs DX1565

+1 to Evans and Jeff’s comments.

I also don’t think you are making a useful comparison – the 650e is an old box. It could be used full range but it was really a mid/hi cabinet needing a sub to take advantage of its output capabilities.

The newer “Gunness Focused” 650z run tri-amped, crossed over to a good double 18 at about 100 – 120 Hz will make a lot of good quality noise, and throw a resonable distance.

The compromises in the DX1565 design are different – it will make more bass but will not go as loud used as a mid/high cabinet compared to a tri amped 650z.

So it depends on what you need...

Hi Peter,

I was using the high-pass specified by EAW for integration with their own SB series subwoofers, so I would argue that it was being measured exactly as the manufacturer intended it to be used. Regardless of the high pass, the MF/HF ran out of gas considerably before the LF did, so lowering or raising the high pass would not have affected anything.

I completely agree that triamping this box and applying Gunness Focusing would likely increase MF/HF output by a bit, but by how much? I was already hitting the MF/HF with 1250 watts, and ignoring losses in the passive crossover, that's quite a bit of power. Is a real-world user going to hit that MF or HF with any more power than that?

And 'throw' doesn't exist. With the exception of a proper line source, the inverse-square law applies: what is louder at the source will be louder far away. Period.
 
Re: Shootout: KF650e vs DX1565

Hi Peter,

I was using the high-pass specified by EAW for integration with their own SB series subwoofers, so I would argue that it was being measured exactly as the manufacturer intended it to be used. Regardless of the high pass, the MF/HF ran out of gas considerably before the LF did, so lowering or raising the high pass would not have affected anything.

I completely agree that triamping this box and applying Gunness Focusing would likely increase MF/HF output by a bit, but by how much? I was already hitting the MF/HF with 1250 watts, and ignoring losses in the passive crossover, that's quite a bit of power. Is a real-world user going to hit that MF or HF with any more power than that?

And 'throw' doesn't exist. With the exception of a proper line source, the inverse-square law applies: what is louder at the source will be louder far away. Period.


Hi Silas,

I usually ran both my 650e’s and 650z’s 3-way active. In 2-way mode, they generally did not have the output I needed. As a guess, I got about 6dB more in 3-way mode.

In 3-way mode with one or two boxes, the lows always ran out first. With six boxes a side the HF was the first to run out. I was using a QSC - PL1.8 on the HF and occasionally it would clip (450W into 8 ohms)

The “Z” versions goes noticeably louder, not far behind an 850. The mids are 109 dB/w/m for the 650z compared to 107 dB/w/m for the 650e and the Z takes a bit more power. The HF diver also does a bit better 110 dB/w/m compared to 107 dB/w/m. The trick to get maximum SPL out of the Z’s was to take the load off the 15 by crossing over to the sub a bit higher – 110 Hz – 120Hz.

Throw --- I will argue that throw does exist but its not related to the inverse square law that everyone seems to take about on this board. People talk about throw because for some reason they perceive some speakers throw more than others do. The question is - what are they talking about? What is it they perceive? I think throw is more about about articulation and clarity at distance than SPL. At say, 300 to 400 ft some speakers will sound clearer and more "in your face" than others.

I attended a shoot out the other day – 8 boxes of db Technologies DVA T12, Nexo Geo 12s and EAW KF730. The T12’s were clear and articulate to about 300ft. The Nexo and EAW had similar clarity but only to about 200ft. The boxes were all at the same SPL level measured at 100ft i.e. the T12s threw 50% further than the Nexo or EAW.

Gunness Focuing (GF) improves clarity: - the frequency, phase and impulse responses are all improved, so it also improves the throw of a speaker, but there is a small price, GF seems costs a small amount of output capacity. It can use quite a bit of energy correcting stuff especially in the VHF area. In some cases (e.g. EAW KF730) there is something like 24dB of boost and cut in the HF driver. That uses amplifier power and adds a little more stress to the mechanical components…. but the sound quality is excellent!

Inside a venue, if you can keep the sound away from the walls and ceiling you will reduce the amount of reverberant energy at the back of the room and the system will be clearer and more "in your face" - the system will be perceived to have better throw.
 
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Re: Shootout: KF650e vs DX1565



In 3-way mode with one or two boxes, the lows always ran out first. With six boxes a side the HF was the first to run out. I was using a QSC - PL1.8 on the HF and occasionally it would clip (450W into 8 ohms)

While we're discussing it, do you happen to know how the limiter behaves in the UX with 650e's? What I mean is if you added more power to the LF (or elsewhere), would it allow short peaks of higher voltage or does it limit quickly to keep the long term power down? I've grown accustomed to having a lot of control over limiting in the Itechs and I'm probably over-thinking this.

What, in your experience, is the best way to size amplifiers to have enough headroom but not be wasting money on amplifier power that the DSP is throttling back?

PS - it sounds like DB has a real winner there!
 
Re: Shootout: KF650e vs DX1565

While we're discussing it, do you happen to know how the limiter behaves in the UX with 650e's? What I mean is if you added more power to the LF (or elsewhere), would it allow short peaks of higher voltage or does it limit quickly to keep the long term power down? I've grown accustomed to having a lot of control over limiting in the Itechs and I'm probably over-thinking this.

What, in your experience, is the best way to size amplifiers to have enough headroom but not be wasting money on amplifier power that the DSP is throttling back?

PS - it sounds like DB has a real winner there!

The limiters in the UX do not give you control of any of the settings. You enter the gain and output power of the amplifier into the UX. From there the UX calculates the rest. If the amplifier is not big enough to take advantage ofthe speakers maximum capabilities the UX will determine the best compromise and prevent the amplifier from clipping.
On the boxes that I have heard using the UX - 650z,730,750,850z, not the 650e, to my ear EAW did a good job of the limiter settings.
 
Re: Shootout: KF650e vs DX1565

The limiters in the UX do not give you control of any of the settings. You enter the gain and output power of the amplifier into the UX. From there the UX calculates the rest. If the amplifier is not big enough to take advantage ofthe speakers maximum capabilities the UX will determine the best compromise and prevent the amplifier from clipping.
On the boxes that I have heard using the UX - 650z,730,750,850z, not the 650e, to my ear EAW did a good job of the limiter settings.

Thanks Peter,

I knew the UX doesn't allow any control of the limiter settings, but I guess what I was hoping to figure out was where and how the limiters are actually kicking in. In reality it's probably not an issue because amplifier power is cheap enough that I'll have more than enough on hand either way.
 
Re: Shootout: KF650e vs DX1565

And 'throw' doesn't exist. With the exception of a proper line source, the inverse-square law applies: what is louder at the source will be louder far away. Period.

The inverse-square law applies to all finite sources, but only in the far field (i.e. when you are far enough away for the source to be well approximated as a point). For a properly long line array, that should be beyond your listening area, so the array can be treated as a line source, yes. But large "point source" arrays may have large enough emitting area that they need to be treated as the area sources they are, which have *no* decrease in output with an increase in distance. This is one of the reasons that larger loudspeaker cabinets aren't measured at 1m.