Hello Wise DIYers,
I'm creating a stand mount speaker pretty similar in nature to the Troels Gravesen Faital 3WC Faital-3WC.
However I would like to use the Faital STH-100 horn and compression driver which I have spare already. The system will be fully active with time delays and FIR processing.
The question I ask of you is should I go for a 6" or 8" midwoofer(or something else)? I would like to cross to the STH Horn at around 1.6KHz or above and not more than 300Hz to the 12".
Any advice or suggestions gratefully received.
Alex
I'm creating a stand mount speaker pretty similar in nature to the Troels Gravesen Faital 3WC Faital-3WC.
However I would like to use the Faital STH-100 horn and compression driver which I have spare already. The system will be fully active with time delays and FIR processing.
The question I ask of you is should I go for a 6" or 8" midwoofer(or something else)? I would like to cross to the STH Horn at around 1.6KHz or above and not more than 300Hz to the 12".
Any advice or suggestions gratefully received.
Alex
You can use the same mid as the Troels design quite successfully.
You can use just about any 6-8" prosound midbass with great results in that range since you'll be running active anyways. If you want to get fancy you can go for something with a copper sleeve in the motor or multiple demodulation rings like BMS.
You can use just about any 6-8" prosound midbass with great results in that range since you'll be running active anyways. If you want to get fancy you can go for something with a copper sleeve in the motor or multiple demodulation rings like BMS.
Agreed. Ive got sth100 and it loses vertical directivity above 2khz and it seems like a 6" driver would suit a bit better than 8". Moreover, it is hard to find 8" pro driver
that didn't have crazy impedance plot wiggles in the 500-1k area. I think those are related to cone resonances mostly. For example the 6rs140 looks nicer in this regard than any other 8" pro drivers i've checked. The 8" mid I have has anything both smooth frequency response and haven't got the system sound right yet despite how much equing and supect the mid driver, but it might be due to any number of other problems as well. Anyway, I'm not sure if these observations have much yo do with perceived sound quality though since my limited experience 🙂 I'd buy two different sets and make prototypes to see which one is better. Good luck, have fun!🙂
that didn't have crazy impedance plot wiggles in the 500-1k area. I think those are related to cone resonances mostly. For example the 6rs140 looks nicer in this regard than any other 8" pro drivers i've checked. The 8" mid I have has anything both smooth frequency response and haven't got the system sound right yet despite how much equing and supect the mid driver, but it might be due to any number of other problems as well. Anyway, I'm not sure if these observations have much yo do with perceived sound quality though since my limited experience 🙂 I'd buy two different sets and make prototypes to see which one is better. Good luck, have fun!🙂
This horn looks difficult to work with. My first thoughts were to cross at 5k with a 4" driver, and obviously that wouldn't be making best use of the CD, or of trying to cross low. I suspect you could find a reasonable solution with anything up to a 10" mid with a bit of luck.
That shouldn't make a difference.
Sometimes it does, although not in theory but in practice.
Allen, why do you think that horn is difficult to use? It's because the vertical directivity differs from the horizontal sligthly in areas other than about 5kHz? Is that a big problem? In a normal vertically aligned multiway loudspeaker, the vertical directivity is narrower around the crossover than the drivers itself suggests because of the usual crossover lobing, so the decreased vertical directivity of that horn even can be an advantage to decrease the crossover lobing. Maybe the creator of the horn want an exact response like that for reason.
My vote for a mid driver as the OP's, a 6" maybe a 8" from Faital (why not?). Namely the 6PR160 or 6RS140, from 8" would be the 8PR200 or 210, maybe the 8RS250.
For one thing, H and V meet up there, suggesting a pattern closer to that of a round driver. Secondly, having the pattern go from narrower vertical to wider vertical can lead to unexpected results.
There are often secondary effects, such as a small change in harmonic distortion. I was speaking about the primary condition.
Why we want a closer radiation pattern to the round midrange driver? Even if more drivers have exactly the same radiation pattern, the vertical and horizontal off-axis sum would differ if the acoustical centers of the drivers are in different locations. And other than coax drivers, the centers are in different places. This is especially true if the acoustical centers are more than 1/4 wavelength distance from each other, like in the typical mid-tweeter situations where the 1 wavelength distance can already be said to be good compromise.
There are lots of compromises in audio but the op can make a great set of speakers with his proposed system.
Can cross at 1.6khz to a 6-8" where both driver and horn are have little pattern control or choose to cross a 6" up at/above 2.5khz where both start to narrow.
Like I mentioned, since this is an active system any driver in that size range can be made flat in the passband and crossed with sharp symmetrical linear phase FIR filters. Save a few crossover points in presets and switch them in real time to compare and choose your favorite. Easy.
Can cross at 1.6khz to a 6-8" where both driver and horn are have little pattern control or choose to cross a 6" up at/above 2.5khz where both start to narrow.
Like I mentioned, since this is an active system any driver in that size range can be made flat in the passband and crossed with sharp symmetrical linear phase FIR filters. Save a few crossover points in presets and switch them in real time to compare and choose your favorite. Easy.
Thank you all and good morning from the UK.
I have to admit i had not really given much thought to the vertical pattern of the horn. I have reasonably high ceilings in the room they will go into and a thick rug on the floor.
I had been leaning more towards an eight in my head due to wanting more membrane for lower midbass. Initially I had not wanted to pay up for both a 6" and an eight inch but as @tmuikku suggested I think I will buy one of each especially as this is a learning build with more speakers to follow..
Thanks for all suggestions and will start a build thread including the testing and measuring of the different mids once I get going.
Alex
I have to admit i had not really given much thought to the vertical pattern of the horn. I have reasonably high ceilings in the room they will go into and a thick rug on the floor.
I had been leaning more towards an eight in my head due to wanting more membrane for lower midbass. Initially I had not wanted to pay up for both a 6" and an eight inch but as @tmuikku suggested I think I will buy one of each especially as this is a learning build with more speakers to follow..
Thanks for all suggestions and will start a build thread including the testing and measuring of the different mids once I get going.
Alex