I've just done my first test with the PA loudspeakers I'm building. I only built one to start so I could assess before making the second pair of boxes (one for the tweeter horn one for the mid horn).
I was pleased with the sound so far (more fine tuning to do but I'm in the ballpark just adjusting levels between the drivers), but I'm not sure how to assess what I'm hearing. What should I be listening for in terms of if the enclosure on the mids is too large or small, or not airtight? Distortion? Sound emanating from the back of the box? Is there a reading I can take? Does it effect frequency response?
I'm especially curious if I'm taking full advantage of the horn loading as it's currently configured, but no idea how to assess that.
I was pleased with the sound so far (more fine tuning to do but I'm in the ballpark just adjusting levels between the drivers), but I'm not sure how to assess what I'm hearing. What should I be listening for in terms of if the enclosure on the mids is too large or small, or not airtight? Distortion? Sound emanating from the back of the box? Is there a reading I can take? Does it effect frequency response?
I'm especially curious if I'm taking full advantage of the horn loading as it's currently configured, but no idea how to assess that.
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I'm not sure how I do that, I know a lot about engineering live sound but little about engineering speakers
You'll want to purchase a DATS test setup if this is something you plan on doing more often. It will give you the basic ability to test your drivers and finished cabs comparatively, plus enable you to import and export data to other programs like REW and Vituixcad. A basic measurement mic with calibration file will take you to the next level of designing. It will also come in handy for your live sound work in more than one way.
I actually don't plan to do this again.
I also don't have the kind of specifications to cross reference, as I am using used custom parts from EAW cabinets, not aftermarket parts with detailed datasheets.
I'm also pretty broke, having just bought everything to put the system together, I might pick up one of those impedance meters down the road, but not today.
I'm not dealing with a problem, everything seems OK, so maybe that's that, but if there's any red flags or telltale signs I can pick up with my ear or metering decibels with a frequency sweep or something like that, let me know.
I also don't have the kind of specifications to cross reference, as I am using used custom parts from EAW cabinets, not aftermarket parts with detailed datasheets.
I'm also pretty broke, having just bought everything to put the system together, I might pick up one of those impedance meters down the road, but not today.
I'm not dealing with a problem, everything seems OK, so maybe that's that, but if there's any red flags or telltale signs I can pick up with my ear or metering decibels with a frequency sweep or something like that, let me know.
If doing strictly by ear and already tried different sealed back (compression, i.e. leak free) chamber net volumes for the (presumed) cone driver mid horn and satisfied with its performance at both low and high power volume, then 'it is what it is' otherwise you'll have to ask specific questions related to its performance.
Note that even if the drivers of both horns are actual horn drivers with sealed backs, the horn/box joint should make them sealed with sufficient stuffing and/or sound deadening pads stuck to the horns to quell any horn body/box resonances comb filtering with the horn's output.
Note that even if the drivers of both horns are actual horn drivers with sealed backs, the horn/box joint should make them sealed with sufficient stuffing and/or sound deadening pads stuck to the horns to quell any horn body/box resonances comb filtering with the horn's output.
I have t tried different volumes (yet). the highs are a compression driver so I'm focussed on the mids. The horns are secure and the braces and the cabs are dampened.
There was a clue in something you said I want to follow up on: "low and high powered volume". So comparing those, if there were an issue, would it be a shift in frequency response or efficiency or something else?
A horn can be viewed as an expanding vent, so if the compression ratio (CR) is too high for the desired bandwidth (BW), then just like a too small a vent will begin to distort/'choke' with increasing power, rolling off its LF BW, ergo so goes a horn and quality of overall performance. Cheap PA horn systems pushed to 'talk' over/through a rowdy crowd is an extreme example.
With no measurements, all one can do is start acoustically large and keep adding scrap/whatever to reduce it till the driver doesn't audibly distort at highest power and/or it's audibly beginning to roll off the bass, so you may not be able to use full power without a steep hi-pass and/or a higher cut-off to protect it.