jdubs said:
Yes, the waveguides are always installed as they are cast into the baffle.
I'm just finishing up a pair for photographs now. Attached you will find a data sheet on the performance. They are very good given the size and cost. I think these will be a big seller.
Harper data sheet
So will a 6" be next?
so as a bit of anecdotal affirmation to the quality of these speakers, I had a family member over who is a bit more involved in the audio industry than I. He mostly does graphic and visual development work, but because of his talent and interest in music, has had numerous commissions to write music for websites, commercials, etc. While I can't say that he has quite the appreciation for good sound that I do, he has certainly heard enough live music and reproduced music, as well as made enough music to know what it should and should not sound like. His initial remark sounded like a complaint, he found them very boring. As he went on with his description, I realized what he meant to say was neutral. he meant they simply seemed to not be there, their sound didn't call attention to itself, the music just seemed to emanate from a space somewhere around the location of the speakers.
He also asked me to turn off the center channel as he wanted to hear how good a job they did imaging without it. He was shocked to find out it wasn't on. In fact, he was so shocked he had to walk up to the center to confirm this was the case. This particular situation has happened with numerous guests listening to my speakers.
The final compliment he paid is a testament to how well the waveguide and controlled directivity approach is working at "widening" my sweet spot, rather than narrowing it, as some people seem to think is the case. My brother was initially sitting in the middle, the best seat in the house if you will. He then moved to the two side sitting positions and noted that while the presentation was not quite so surreal, it still maintained proper image height and specificity, and the image really didn't shift. He also noted that the sound wasn't dull at these angles, as he had expected.
So in case anyone is considering these speakers but has reservations due to imaging, center image, or the width of the sweet spot, please have no worries. I feel it's really inaccurate to assume that by controlling the directivity you have narrowed the listening window. My experience has been the opposite, and I do believe that the data supports this quite well.
so as a bit of anecdotal affirmation to the quality of these speakers, I had a family member over who is a bit more involved in the audio industry than I. He mostly does graphic and visual development work, but because of his talent and interest in music, has had numerous commissions to write music for websites, commercials, etc. While I can't say that he has quite the appreciation for good sound that I do, he has certainly heard enough live music and reproduced music, as well as made enough music to know what it should and should not sound like. His initial remark sounded like a complaint, he found them very boring. As he went on with his description, I realized what he meant to say was neutral. he meant they simply seemed to not be there, their sound didn't call attention to itself, the music just seemed to emanate from a space somewhere around the location of the speakers.
He also asked me to turn off the center channel as he wanted to hear how good a job they did imaging without it. He was shocked to find out it wasn't on. In fact, he was so shocked he had to walk up to the center to confirm this was the case. This particular situation has happened with numerous guests listening to my speakers.
The final compliment he paid is a testament to how well the waveguide and controlled directivity approach is working at "widening" my sweet spot, rather than narrowing it, as some people seem to think is the case. My brother was initially sitting in the middle, the best seat in the house if you will. He then moved to the two side sitting positions and noted that while the presentation was not quite so surreal, it still maintained proper image height and specificity, and the image really didn't shift. He also noted that the sound wasn't dull at these angles, as he had expected.
So in case anyone is considering these speakers but has reservations due to imaging, center image, or the width of the sweet spot, please have no worries. I feel it's really inaccurate to assume that by controlling the directivity you have narrowed the listening window. My experience has been the opposite, and I do believe that the data supports this quite well.
Are you talking about crossing the speakers' main axis in front of the listening position? With that kind of setup, center phantom images are much more stable when moving to the left or the right but I also experience a narrower sound stage. I now use a toe-in of 15° which "opens up" the sides - much better localisation and widened sound stage. Sound reproduction is all about trade-offs.
Best, Markus
Markus, that "broad peak" is less than 1 dB and is in fact in the driver, which has a continuously rising output with frequency. It probably appears more like a peak than it is because of the "hole" just before it, which again is in the driver, I believe. I will admit to becoming somewhat concerned about this hole since it appears in all the systems at just about the same frequency even though all the drivers are different. Since it is in the nearfield measurement, it is not diffraction or reflection, however, it could be a resonance in the stand. I am looking into this. However, we had these same kinds of holes in Thailand and the stand there was completely different. Further when we asked B&C about it they commented that they don't see it, but yet when they did a nearfield in the same way that we did our results were exactly the same and the hole was there. I believe that it is a spider resonace and appears at about the same frequency for all the woofers since the spiders are all quite similar. But it does seem to go away at far field distances. Far field seems to smooth out a lot of problems that I see in my measurements.
As to the 15 degree toe-in versus 22.5, your room is so small and you sit so close that this could be the difference that you see. Matt and I both have much bigger rooms and distances and find the same 22 degree angles work the best.
As to the 15 degree toe-in versus 22.5, your room is so small and you sit so close that this could be the difference that you see. Matt and I both have much bigger rooms and distances and find the same 22 degree angles work the best.
Yes, as Dr. Geddes said, i'm using a 22 degree toe in. I'm not finding quite the trade off you mentioned, but my speakers are pretty far apart due to the 84" width of my screen. They are about 90" apart and roughly 170" from the listening position. My listening positions are roughly 30" from the rear wall, which is closer than I would like it, but is as good as I could get. I'd prefer to be in excess of 100" from the rear wall. However I am in excess of 100" to the right nearest wall. The left wall is strange, it has a fireplace which meets the back and side wall at something like a 30-40 degree angle, which makes a portion of it closer to me than the rear wall and has caused some strange reflection/diffraction issues. This is one thing I hope to fix with further room treatment, but a redesign of the fireplace mantle went a pretty long way, as did a mix of absorption and diffusion devices (far more diffusion than absorption).
Speaking of room acoustics, a project I've been planning and partly completed is a rear and side wall diffusion device which utilizes a media/book case with a rear panel that forces the books to stick out at precise quadratic positions. I utilized a quadratic diffuser formula to calculate the correct dimensions, spacing, etc., then scaled that to books and dvd's I have. I read about someone else doing something similar and just the idea a little further by applying correct mathematics to the situation. The biggest problem I'm yet to overcome is that if I treat each shelf as it's own diffuser, the low end of the diffusion is limited. However, I suspect that it functions as more of a whole than this would allow, but probably not the same as if it were one big unit. For instance, the individual "recesses" are not as tall since they are divided by the shelf.
Dr. Geddes, I'm awaiting this sub line. My current solutions are getting me by, and I probably due have better bass than quite a few people who are plenty content, but measurements have left me dissatisfied. My next big sound expenditure will be to improve the low end through a mixture of two of your "subs" and some room rearranging. I'm probably going to utilize my biggest current subwoofer as my ULF in the corner. I suppose I could stack the other one on top since I have it, but really, that single sub is capable of well in excess of 115db's at 20hz, and I don't listen at such levels hardly at all. It's the range above 50hz that needs work right now.
Speaking of room acoustics, a project I've been planning and partly completed is a rear and side wall diffusion device which utilizes a media/book case with a rear panel that forces the books to stick out at precise quadratic positions. I utilized a quadratic diffuser formula to calculate the correct dimensions, spacing, etc., then scaled that to books and dvd's I have. I read about someone else doing something similar and just the idea a little further by applying correct mathematics to the situation. The biggest problem I'm yet to overcome is that if I treat each shelf as it's own diffuser, the low end of the diffusion is limited. However, I suspect that it functions as more of a whole than this would allow, but probably not the same as if it were one big unit. For instance, the individual "recesses" are not as tall since they are divided by the shelf.
Dr. Geddes, I'm awaiting this sub line. My current solutions are getting me by, and I probably due have better bass than quite a few people who are plenty content, but measurements have left me dissatisfied. My next big sound expenditure will be to improve the low end through a mixture of two of your "subs" and some room rearranging. I'm probably going to utilize my biggest current subwoofer as my ULF in the corner. I suppose I could stack the other one on top since I have it, but really, that single sub is capable of well in excess of 115db's at 20hz, and I don't listen at such levels hardly at all. It's the range above 50hz that needs work right now.
gedlee said:
Your diagram is somewhat hard to read because of its unusual gradation and missing labeling (is the frequency response smoothed?). We see 5° increments, right? So yellow is 15° and purple/blue 20° (the recommended listening axis). Between 150Hz and 900Hz the amplitude rises more than 2.5dB for 15° and 4dB for 20°. This should be audible as strong coloration because the peak is very wide (more than 2 octaves). I'm referring to http://www.gedlee.com/downloads/harper_h.pdf
gedlee said:
Maybe I wasn't very clear, I do not toe-in 45° but 15°. The speakers 0° axis crosses behind the listening position. How far are you and Matt from your speakers?
Best, Markus
pjpoes said:
pjpoes, when you toe in 22° then you end up listening on the speakers' 8° axis!? Earl's recommendation is more like this:
An externally hosted image should be here but it was not working when we last tested it.
Best, Markus
Markus
The lines are every 7.5 degrees and the red lines are at +-2 dB. They are smoothed to 1/6 oct. Relative to 0 dB there are no variations greater than 1 dB below 1 kHz. and relative to -2 dB /decade falloff of the HF response above that (which I use as a target) there are no more than +-1 dB variation at 22.5 degrees from 150 Hz to 15 kHz.
If you pick the reference point at a flat -2 dB then its different. Peaks and dips are all relative.
And remember this is a Harper NOT and Abbey.
The lines are every 7.5 degrees and the red lines are at +-2 dB. They are smoothed to 1/6 oct. Relative to 0 dB there are no variations greater than 1 dB below 1 kHz. and relative to -2 dB /decade falloff of the HF response above that (which I use as a target) there are no more than +-1 dB variation at 22.5 degrees from 150 Hz to 15 kHz.
If you pick the reference point at a flat -2 dB then its different. Peaks and dips are all relative.
And remember this is a Harper NOT and Abbey.
Earl,
so yellow is 22.5°? Tried to match the red lines to the dB scale: it doesn't correspond with the labeling of the y-axis. Would you be so kind to post a frequency response curve that matches the labeling? Otherwise it's hard to evaluate your data.
Looks like the Harper will sound highly colored due to the two large peaks from 150Hz-900Hz and 1kHz-3kHz? An additional plot of the listening axis with 1/3 octave smoothing might be more adequate to show how flat the Harpers really are.
Why do you want to have a HF falloff? We're looking at anechoic data and not a room response curve that matches some kind of "house curve" one might want to achieve?
Best, Markus
so yellow is 22.5°? Tried to match the red lines to the dB scale: it doesn't correspond with the labeling of the y-axis. Would you be so kind to post a frequency response curve that matches the labeling? Otherwise it's hard to evaluate your data.
Looks like the Harper will sound highly colored due to the two large peaks from 150Hz-900Hz and 1kHz-3kHz? An additional plot of the listening axis with 1/3 octave smoothing might be more adequate to show how flat the Harpers really are.
Why do you want to have a HF falloff? We're looking at anechoic data and not a room response curve that matches some kind of "house curve" one might want to achieve?
Best, Markus
gedlee said:
(...2 pages back)
There is a BW 60-130Hz (-6dB) on AI website. It is a mistake, isn't it? Seems to me little bit on high side. Even if I mentally add room mode contribution I cannot expect adequate in-room response below say mid 40's.
40-90Hz BW with few dB loss in sensitivity seems to me more usable solution.
It's not meant as a true subwoofer in the sense most are used to. It's meant as a bass augmentation woofer to handle the area of greatest modal density in the room. If you read the various discussions of Dr. Geddes method, he recommends multiple subwoofers in the range between 50 and say 150hz, with a single subwoofer to handle the very low frequencies below 50hz.
I believe that the reason behind Dr. Geddes choice of initial offering here is that lots of perfectly acceptable subwoofers exist, but few if any higher range subwoofers exist. HSU does offer a sort of BB subwoofer, but other than that, few exist. You could go with a pro audio subwoofer, but then in many cases the size is large, the finish is wrong, and typically cost more than what Dr. Geddes seems to be offering.
I believe that the reason behind Dr. Geddes choice of initial offering here is that lots of perfectly acceptable subwoofers exist, but few if any higher range subwoofers exist. HSU does offer a sort of BB subwoofer, but other than that, few exist. You could go with a pro audio subwoofer, but then in many cases the size is large, the finish is wrong, and typically cost more than what Dr. Geddes seems to be offering.
markus76 said:
I plotted two lines, one at -2 dB and the other at +2 dB. Thats whats on the graph.
I used to do all the systems flat, they always sounded bright. This, of course, is going to be the case because the power response of a CD speaker at the HFs is well above that of any piston speaker. This situation is also discussed at Etymotic Research site about EQing insert earphones. When the eardrum pressure response is flat, they will sound bright. Mead claims this is due to the EQ of most recordings which are adjusted to compensate for the power response falloff of most speakers.
Your speakers are flat, so if you like it that way fine. But most everyone will say that flat is slightly bright.
gedlee said:
The shape of your pixels might be different from mine
This is what I see:An externally hosted image should be here but it was not working when we last tested it.
gedlee said:
Sounding speakers is a dangerous thing to do because you assume that a) every speaker used in mixing/mastering is a piston speaker and you assume that b) the end users room acoustics is known.
You somehow undermine your own CD approach: Why use CD at all when it only sounds "right" if the power response is similar to that of a piston speaker?
Best, Markus
Markus
Thats what I see too, I don't see your point. Are you saying that the -2 dB line is a fraction too low? By what a tenth of a dB!?
You are preaching to the choir about voicing speakers being dangerous and why. But there is no doubt about the "brightness" issue, I've lived with this for years and almost everyone finds the same thing. I used to say to turn down the trebble a little bit unit the sound is more nuetral, but so many people don't have trebble controls and want it done in the crossover.
Thats what I see too, I don't see your point. Are you saying that the -2 dB line is a fraction too low? By what a tenth of a dB!?
You are preaching to the choir about voicing speakers being dangerous and why. But there is no doubt about the "brightness" issue, I've lived with this for years and almost everyone finds the same thing. I used to say to turn down the trebble a little bit unit the sound is more nuetral, but so many people don't have trebble controls and want it done in the crossover.
1+1 is 2. It should be trivial for you to match labeling and curves in a simple frequency plot. You make your data look imprecise. People might draw the conclusion that the data itself is imprecise. Who knows?
Don't you think the broad peak centered around 500Hz is audible?
Another questions has been left unanswered: how far from the speakers is the listening position in your home theater?
Best, Markus
Don't you think the broad peak centered around 500Hz is audible?
Another questions has been left unanswered: how far from the speakers is the listening position in your home theater?
Best, Markus
Markus
I have no idea what you are talking about in the plots. I even checked the locations for the + and - 2 dB lines and they are very close to where they should be, maybe a couple of tenths of a dB off, nothing noteworthy. I simply don't understand your issue here.
No I don't think that "broad peak" would be all that audible, but the real point is that there isn't anything that can reasonably be done about it. What small speakers like this never have colorations!!
I do think that the peak at 3 kHz may be a bit too large, maybe 1 dB or so, and this can be lowered since this is possible in the crossover, but the LF drivers response is not alterable by the crossover in any reasonable way.
Just go active, I guess, and fix everything. This would only DOUBLE the cost of the system!
My real concern with the Harpers is how well they will work as surrounds. They are not so good on axis so I guess that they should be placed so that the listeners are slightly off axis - not always easy with surrounds.
Personally, I'd love to see you actually design and build a loudspeaker system within a fixed budget so that I could nit-pick it to death like you do to mine. It's so easy to be critical about something that you have never done yourself.
I sit back about 12 feet. The speakers cross about four-six feet in front of the lsiteners.
I have no idea what you are talking about in the plots. I even checked the locations for the + and - 2 dB lines and they are very close to where they should be, maybe a couple of tenths of a dB off, nothing noteworthy. I simply don't understand your issue here.
No I don't think that "broad peak" would be all that audible, but the real point is that there isn't anything that can reasonably be done about it. What small speakers like this never have colorations!!
I do think that the peak at 3 kHz may be a bit too large, maybe 1 dB or so, and this can be lowered since this is possible in the crossover, but the LF drivers response is not alterable by the crossover in any reasonable way.
Just go active, I guess, and fix everything. This would only DOUBLE the cost of the system!
My real concern with the Harpers is how well they will work as surrounds. They are not so good on axis so I guess that they should be placed so that the listeners are slightly off axis - not always easy with surrounds.
Personally, I'd love to see you actually design and build a loudspeaker system within a fixed budget so that I could nit-pick it to death like you do to mine. It's so easy to be critical about something that you have never done yourself.
I sit back about 12 feet. The speakers cross about four-six feet in front of the lsiteners.
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