stevie

Evaluating (or designing) a speaker cab by measuring it is infinitely more complex than micing up a cab for recording or sound reinforcement. You need a calibrated mic for a start. There's a whole battery of measurements you need to carry out using specialist software. Done properly, however, you can form a reasonably accurate idea of how a speaker will perform (although your ears will always be the final arbiter). To measure a loudspeaker, you need to place the mic in what is termed the "far field" - or between 4 and 6 feet for the Monaco or similar cab. Any closer than this and the two drivers are not fully integrated. I've found measuring on the tweeter axis to be the most useful position. To remove the impact of the room in the absence of an anechoic chamber, the test tones from the speaker have to be "gated" in software. Unfortunately, this useful technique doesn't allow measurement at low frequencies. So, the low frequency response has to be checked separately using either near-field or ground plane measurements. The two measurements are then adjusted for level and spliced together to create a full-range response. If you're a stickler, you also measure and splice the response of the port. This gives you the frequency response on axis, and you've only just started.😀

@Wolverinebass has a point. Half of the sound is coming from the bass driver and half from the horn. So, how do you mic up? I made some quick measurements on a Monaco cab with the mic pointed at the horn. The top one (black) is relatively close, maybe about 30cm. The measurement looks quite clean but there's a distinct dip between 600Hz and 2kHz, which will affect the sound - it's two octaves. This is because the mic is well off axis in relation to the bass driver. The red measurement is from about one metre. You can see that the dip caused by the bass driver has more or less filled in. However, at that distance, room effects are going to be noticable. In this measurement, you can see the change between 200 and 600Hz caused by room reflections. So, measuring at 1 metre is more accurate but the sound is likely to be affected by room reflections or other noises (instruments). The logical conclusion would be to position the mic in between both drivers, which should allow the mic to be positioned closer. I'm so used to measuring on the tweeter axis that I didn't consider it at the time, but I can take a measurement in between the drivers is anyone would like to see it. I do agree with @matybigfro, however. The design goal of the Monaco (and other LFSys speakers) is to reproduce the sound from the amp as accurately as possible. It makes a lot more sense to DI.

I'd be happy to post a link once I've tidied it up. It needs a good editing.

There's a relationship between cabinet size and sensitivity: all things being equal, a larger cab will be more sensitive than a smaller one. In my experience, the Goodwood is louder than the BF One10, but because it uses neodymium drivers, weighs about the same. I have a smaller cab in the works that is currently undergoing field testing. That could be a contender for your project, @funkle, and I could include you as one of the field testers if you like.

Yes, that's the experience most people have. Odd, isn't it? The orientation of the horn is one aspect. Another is that the compression driver takes over from below 2kHz, which means you get a controlled dispersion throughout the range of bass guitar frequencies - no matter where you're standing. I've written a short article for @Sean and will probably post it on the website once I get some explanatory diagrams done. I already have some frequency response curves that show what is going on.

Sure, no problem. PM on its way.

I can explain why this is happening and why LFSys cabs have been designed specifically to fix this problem. But I'm sure someone else who's not as heavily invested in LFSys will explain.

That's always good to know.😀

Here's a BMW 330 convertible with two Monza cabs. The BMW has a 210-litre boot.

Thanks for the recommendations, guys. I can confirm that the Monaco handles a B string with ease. In fact, all the LFSys cabs do - even the modest Goodwood. Unsurprisingly, the more expensive cabinets go louder - so the Monaco would be the top choice if it fits in the boot. However, it's not simply a matter of whether it will fit; it's whether you can get it in and out. The handle on all LFSys cabs is at the top. So, if you place the cab in the boot sideways, you'll need enough space on both sides to put your hands in to lift it out (if you follow me). If the Monaco proves to be too big, the Monza is almost certainly going to fit. The MX5 has a 130-litre boot. Here's a photo of two Monzas in a Honda Jazz, with a 300-litre boot just over twice as big. As you can see, there's plenty of space left over.

I can paint the baffle any colour you like as long as it's British Racing Green. 😀 Only joking.... if you want a different coloured baffle, you just need to give me the paint reference (RAL number ideally). There's no extra charge.

The wood looks nice. I'd expect a stained finish to look good.

You just beat me to @BigRedX. Absolutely right.

You can't complain about that.

It's even worse. The E112 contains higher spec components than the K12 - larger voice coils in both the LF and HF drivers. I'd guess an honest power rating for the K12 would be 300 watts. Problem is, if they published the honest rating, nobody would buy them because the competition are pulling the same trick. 😀