True, I've got some time off for the next few weeks so maybe I'll be able to get further than owing it and move onto to making use of it
Not really, I don't intend to use a 2" driver, impedance in the datasheet looks like there are a few lumps under the smoothing though. I'm more inspired by Legis's build using the HF1440 or HF108. A smaller source stops the polar collapsing as badly further off axis.
This ND2080A in 8 ohms version seems top have a good enough high end. But as a 2", I don't know how it could perform off axis and if the horn directivity can deal in the highs with such 2" in spite of a 1"...
But indeed Earl G. is ok with 1" for low crossover in home hifi context. the 1.4" HF1440 measures fine but when I see the flat impedance curve of the ND2080A I was wondering ifi t could be a better candidate.
But indeed Earl G. is ok with 1" for low crossover in home hifi context. the 1.4" HF1440 measures fine but when I see the flat impedance curve of the ND2080A I was wondering ifi t could be a better candidate.
Without something like mabat's ESP or the Klipsch nested plug attachment any 2" driver is going to have the high frequencies drop very quickly off axis. Depending on the use case this may or may not cause a big problem. In the simulations of the more optimised radial horns there was about a 60 degree window of good directivity before the size of the source took over due to the fin arrangement.
It is debateable where a compression driver that has a double or triple peak impedance is worse than some some of the newer designs that have a more direct radiator like impedance, like the ND2080A or the Faital HF108. Having a better and flatter impedance is a good thing in general but if there is no disturbance in the frequency response and the burst decay is clean there doesn't seem much to worry about.
Certainly something aiming to be more coaxial over a wide enough bandwidth is attractive. Is it worth the effort or is it just another different set of compromises, I don't know. Hopefully the slightly more conventional builds will help me to see what I like and don't like about the different approaches. I've got enough drivers now to try most of the approaches I can see value it pursuing.
After you get CNC working, you will need to get a pallet of BB delivered
First you try in simulation. Then filter and build select few. I'm walking that path also but towards a single build.
re' more coaxial
Its not just what sounds the best; also usage model. More coaxial gives you extended vertical listening window. Its also easier to add cardioid to get extended directivity control and placement freedom in a smaller foot print. You might not care about any of that if you have a dedicated listening room.
But it also results in excellent power response and excellent dynamics, which I'm sure you do care about, even though its not the only way to get those features.
First you try in simulation. Then filter and build select few. I'm walking that path also but towards a single build.
re' more coaxial
Its not just what sounds the best; also usage model. More coaxial gives you extended vertical listening window. Its also easier to add cardioid to get extended directivity control and placement freedom in a smaller foot print. You might not care about any of that if you have a dedicated listening room.
But it also results in excellent power response and excellent dynamics, which I'm sure you do care about, even though its not the only way to get those features.
Right after I re-mortgage the house. I will be using MDF for most things at least at the beginning. Quite possibly the only thing made out of birch ply will be the CNC table top
This is the choice of trade offs, none of those things come without a counter argument to choose something else. How and where the speaker will be used is a big part of choosing which way to go for sure.
The 15NBX100 is more of a (sub)woofer than a midwoofer and in practice I have only encountered the NBX in subwoofer applications.
There are 2 (main) issues:
- the heavy cone, heavy motor and suspension > needs lots of power, or rather: it's designed to withstand a lot of power/torture
- Le is high.
Some French DIY folks have tested the NBX and found it to sound muffled above 500Hz, which makes perfect sense, considering the parameters.
The 15NTLW3500 is a midwoofer, but I'd consider it overkill for hifi. It's well known that the best midwoofers for hifi are often the most basic ones.
One example is the Celestion FTR15-3070C, which handles bass and midrange (up to ca. 1200 Hz) equally well. According to 2 leading German DIY magazines it's one of the best measuring and sounding 15s ever, regardless of the price.
It is no coincidence that the response of my own woofers is similar:
Indeed, similar. The 15FH500 is a bit more heavy duty (motor + moving parts) with lower Fs and subsequently higher Xmax and higher Le.
I'd use the Faital below and the Celestion up to 1000Hz as indicated by the first impedance ripples. The Celestion needs a larger cab to go low.
I'd use the Faital below and the Celestion up to 1000Hz as indicated by the first impedance ripples. The Celestion needs a larger cab to go low.
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