I'm playing with x-over points on a speaker. Here are a few measurements off axis. One horizontally at 60 degrees, and three vertical. The angles were estimated by eye. The thirty and 45 degree horizontal measurements only had mild dips. Actually, the 30 degree measurement looked pretty smooth
My room is bare sheet rock, and has carpet on the floor. I was wondering if the dips might actually be an advantage. So far, I only have one speaker built, and I'm thinking about building the second. I was using this speaker as a center channel. I have several x-overs. This is just one of my considered designs. I'm not sure if I want to attempt an audiophile design with this, or a HT set of mains. I also have some Peerless tweeters with a mild horn, or waveguide that I could use, but I'll have to build two boxes if I go that route.
The on axis isn't shown, but was pretty flat.
My room is bare sheet rock, and has carpet on the floor. I was wondering if the dips might actually be an advantage. So far, I only have one speaker built, and I'm thinking about building the second. I was using this speaker as a center channel. I have several x-overs. This is just one of my considered designs. I'm not sure if I want to attempt an audiophile design with this, or a HT set of mains. I also have some Peerless tweeters with a mild horn, or waveguide that I could use, but I'll have to build two boxes if I go that route.
The on axis isn't shown, but was pretty flat.
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It is difficult to comment sensibly on the information that you have shown. Possibly it doesn't look unreasonable, maybe a bit too much in the 5-6KHz range
If you could provide, more files in the horizontal plane that would help a lot. Manufacturers data sheets give response data for on axis plus 30 degrees , 45 and sometimes 60 degrees in azimuth when measured at 1metre distance.
Measuring at a distance greater than 1 metre can be done, but it is difficult to not pollute the data captured with reflections creeping in to the time window.
If you could provide, more files in the horizontal plane that would help a lot. Manufacturers data sheets give response data for on axis plus 30 degrees , 45 and sometimes 60 degrees in azimuth when measured at 1metre distance.
Measuring at a distance greater than 1 metre can be done, but it is difficult to not pollute the data captured with reflections creeping in to the time window.
Could be, and better if the rest of the treble toward the ceiling is down also..
Putting various files like this into vituixcad, it can show you a guess at the angles in between and calculate averages from what it has.
The tweeter has a good strong off axis. I have, and could use this tweeter..(https://www.parts-express.com/pedocs/specs/264-1386--tymphany-h26tg45-06-spec-sheet.pdf.).. it would reduce some of that 5k energy, but I wonder about the importance. If I loved making boxes, I'd just knock one out, and see.
I understand about making boxes, in that it can become very much a chore. If you are happy with the resulting sound, the jobs done.
Trying the horn loaded tweeter you will still have to blend it in, and adjust L and C components plus some more resistive padding I guess.
Trying the horn loaded tweeter you will still have to blend it in, and adjust L and C components plus some more resistive padding I guess.
I'm trying to decide what I ultimately want from this pair of speakers. There's less work to build one box like this, but the other tweeter might work even better for home theater action movies that get loud. I can cross high, or low. Crossing high is good for the HT, but possibly a compromise for music.
I have already revised the x-over. This one is crossed at 3k. Off-axis looks about the same as the previous that was 4k. Either tweeter can handle 3k easily, even for HT.
Here's the on axis alone. It's gated, but has no smoothing. Then the on axis through 60 degrees are 1/6th smoothing, and on the same graph. The dip around 3k is caused by the mid-bass . Crossing at 3k helped slightly I think. I generally cross below 2k.
Making a new x-over if I switch tweeters is no problem. I'm really just trying to decide which route to take.
I have already revised the x-over. This one is crossed at 3k. Off-axis looks about the same as the previous that was 4k. Either tweeter can handle 3k easily, even for HT.
Here's the on axis alone. It's gated, but has no smoothing. Then the on axis through 60 degrees are 1/6th smoothing, and on the same graph. The dip around 3k is caused by the mid-bass . Crossing at 3k helped slightly I think. I generally cross below 2k.
Making a new x-over if I switch tweeters is no problem. I'm really just trying to decide which route to take.
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Its subtle but I think it looks like it has flatten things just a little bit more.
You understand this stuff well enough, simply from from the graphs you have provided, plus you know that either tweeter can handle 3KHz. It seems like you are getting close to a good design.
I do not know anything about the idea of voicing for HT, but it is a pretty flat response as it is, which should give good voice intelligibility should be high anyway. I don't know if you are bothered by sibilance, but if you are and can hear it you may have to shade back a bit on the level in that area of the frequency band.
You understand this stuff well enough, simply from from the graphs you have provided, plus you know that either tweeter can handle 3KHz. It seems like you are getting close to a good design.
I do not know anything about the idea of voicing for HT, but it is a pretty flat response as it is, which should give good voice intelligibility should be high anyway. I don't know if you are bothered by sibilance, but if you are and can hear it you may have to shade back a bit on the level in that area of the frequency band.
I took a shot at notching the 12k range before posting the measurements, but the filter didn't work as expected for some reason.. I left it as shown for the time being.
The x-over part count is already a bit high, and this is a small 12" tall box with a 6.5" woofer. It would be very crowded with 4 coils to keep spaced apart, and oriented correctly. If I only want it for HT duty, I have a simpler filter, and the response can be flattened out with a couple of small EQ adjustments. I would rather it be all passive so that I can use them for 2-ch with some other better equipment, and no EQ. I have another pair of speakers with a similar potential problem. They currently have EQ from an AVR as part of the x-over. Before I did that, they were totally passive, and I think they sounded better passive, but that may be due to the equipment. . I want either that pair, or this pair to be my 2-ch optimized speaker. The other can be optimized for HT.
A bigger box would make things easier, but I kind of like the small cube like look. In addition, this tweeter can cross below 2k, which should fill the 3k off-axis. It's a relatively expensive tweeter, and if I destroy it watching an action movie, I don't want to buy a new one.
The x-over part count is already a bit high, and this is a small 12" tall box with a 6.5" woofer. It would be very crowded with 4 coils to keep spaced apart, and oriented correctly. If I only want it for HT duty, I have a simpler filter, and the response can be flattened out with a couple of small EQ adjustments. I would rather it be all passive so that I can use them for 2-ch with some other better equipment, and no EQ. I have another pair of speakers with a similar potential problem. They currently have EQ from an AVR as part of the x-over. Before I did that, they were totally passive, and I think they sounded better passive, but that may be due to the equipment. . I want either that pair, or this pair to be my 2-ch optimized speaker. The other can be optimized for HT.
A bigger box would make things easier, but I kind of like the small cube like look. In addition, this tweeter can cross below 2k, which should fill the 3k off-axis. It's a relatively expensive tweeter, and if I destroy it watching an action movie, I don't want to buy a new one.
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Sometimes a simple CR network in parallel with the tweeter can provide a solution in the top octave. It can be a cheap fix.
I connected an LCR, and the entire tweeter response dropped about 5dB. There's a chance that the AVR used for the sweeps, didn't like the load, and tried to protect itself.
I do not know what 1.5uF and 6ohms would do as a starting point?
Worth checking in a sim and also verify overall speaker impedance if that amp went into protect.
Worth checking in a sim and also verify overall speaker impedance if that amp went into protect.
I sometimes do that after I'm done, or close to done with a x-over. This AVR says 8 ohms minimum. I have other amplifiers rated for 4 ohms. I want to be able to use either. I suspect that I'm right around 4 ohms through the midrange currently, due to a shaping LCR that pulls down the 1k range a few dB. I should check before I go much farther.
As long as the dispersion is what you require, EQ is the way to remove this energy. You could change the tweeter but since similar domes in a similar box will have similar dispersion, they will act and sound similar once you EQ them to be the same.
Hi OP!
I have some perspectives which may help you. My experience comes from motion picture equipment design in the past, and living with no center, as well as a 2 and 3-way center I built.
It's important to really understand when and where a center channel speaker adds high value. IMHO that's the same for auditoriums as well as homes. For theaters the key value was in keeping the dialogue centered regardless of the seating position of the patron, which could be up the middle, or far to the sides. Of course in these cases we are talking about tens of feet differences.
For the home listener the value is the same. Whether you are lying down on the couch, grabbing chips from the counter or sitting in the middle the center channel keeps that dialogue and centered effects in the center. This then makes exactly what you want the center to do important. If your listening location is always in either of two recliners right in front of the screen then a center may not even add much. So, if that's not your case, what exactly are your listening angles? For this maybe 30 degrees horizontal is the extreme. The same considerations should be given to vertical listening angles. How wide does it need to be and also whether your prime listening angle will be above the tweeter axis. Your delay and phase considerations should take this into account.
This is important to consider because as part of your decision making is whether to use a 2-way, 3-way or maybe even a woofer-assisted wide band (WAW) design. You can get away with 2-way and lower order filters if you know in advance that your actual listening locations are constrained anyway.
Last tip I have is that higher order filters make off angle nulls less severe, as does using a plate amp with built in DSP capabilities. Having made a few passive speakers successfully and having made a center channel using a Hypex plate amp I can honestly say I don't think I'm ever deliberately making a passive crossover again. Too much effort with too little return. Also, if you want to see a collection of DIY center speakers check out Troels Gravesen's site, which has maybe 6 different center channels with off-axis responses.
I have some perspectives which may help you. My experience comes from motion picture equipment design in the past, and living with no center, as well as a 2 and 3-way center I built.
It's important to really understand when and where a center channel speaker adds high value. IMHO that's the same for auditoriums as well as homes. For theaters the key value was in keeping the dialogue centered regardless of the seating position of the patron, which could be up the middle, or far to the sides. Of course in these cases we are talking about tens of feet differences.
For the home listener the value is the same. Whether you are lying down on the couch, grabbing chips from the counter or sitting in the middle the center channel keeps that dialogue and centered effects in the center. This then makes exactly what you want the center to do important. If your listening location is always in either of two recliners right in front of the screen then a center may not even add much. So, if that's not your case, what exactly are your listening angles? For this maybe 30 degrees horizontal is the extreme. The same considerations should be given to vertical listening angles. How wide does it need to be and also whether your prime listening angle will be above the tweeter axis. Your delay and phase considerations should take this into account.
This is important to consider because as part of your decision making is whether to use a 2-way, 3-way or maybe even a woofer-assisted wide band (WAW) design. You can get away with 2-way and lower order filters if you know in advance that your actual listening locations are constrained anyway.
Last tip I have is that higher order filters make off angle nulls less severe, as does using a plate amp with built in DSP capabilities. Having made a few passive speakers successfully and having made a center channel using a Hypex plate amp I can honestly say I don't think I'm ever deliberately making a passive crossover again. Too much effort with too little return. Also, if you want to see a collection of DIY center speakers check out Troels Gravesen's site, which has maybe 6 different center channels with off-axis responses.
I got curious, so I measured my other "audiophile wannabe" speaker. It's my favorite so far for 2-ch, although this measurement is with the AVR EQ, and I think shortly will be returned to full passive.
I also compared distortion. It's very close, but the one I'm working on is slightly better. This one is a 5.25" 2-way. I believe the off-axis on this one is better.
I also compared distortion. It's very close, but the one I'm working on is slightly better. This one is a 5.25" 2-way. I believe the off-axis on this one is better.
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