Hi Kees,
Thanks for the feedback. I was concerned that Hornresp would not be able to correctly model the acoustical impedance loading the down-firing diaphragm. What value are you using for the Ang parameter?
I can't see why there should be a problem.
Kind regards,
David
Thanks for the feedback. I was concerned that Hornresp would not be able to correctly model the acoustical impedance loading the down-firing diaphragm. What value are you using for the Ang parameter?
I can't see why there should be a problem.
Kind regards,
David
Hi Greebster,
Sorry to learn of your misfortune. I suspect that the book was packed and shipped in good condition, but suffered at the hands of a courier somewhere along the way. Like Mark, my copy arrived in absolutely perfect condition from England.
Kind regards,
David
Hi mark100,
Reverse the sequence of events. Rather than setting the filters and then trying to use the Maximum SPL tool, use the Maximum SPL tool first and then set the filters. The Active and Equaliser filters can be used, but not the Passive or Le Cléac'h options.
Kind regards,
David
Hi Bill,
It's an issue not just confined to Hornresp
.Trying to exactly match an oblate spheroidal waveguide segment to a Le Cléac'h segment is a bit like juggling six balls in the air together - not that easy to do.
Getting the Obl mouth area to equal the Lec throat area, the Obl mouth Fta to equal the Lec throat Fta and the Obl mouth radius of curvature to equal the Lec throat radius of curvature all together, is effectively impossible to do.
Kind regards,
David
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Hi David, papasteack, and nc535,
Thank you for your replies. I think I've been doing everything OK, and now see how to get the information I've been looking for.
David, I was doing as you say, running the Max SPL tool first, and then setting filters in the Filter Wizard.
After that I was rerunning Max SPL to see if it incorporated the effects of the filters. The rerun of Max SPL appears to default back to unfiltered output.
All I really was looking for was the effect on displacement, given the filters used.
And I now see there is a displacement view selection in the filter wizard...which only makes it easier... perfect.
I'm working on frequency specific limiting, to limit only the frequency region of excess displacement. I can handle driver power limiting easily enough with RMS and peak limiting in my processor.
I'd like not to pull down the entire sub output to address displacement limitations at particular frequencies.
It's a fun processing attempt, using essentially parametric-width notch filters along with a sidechain limiting trigger ....
...and is very much being aided by Hornresp
Thank you for your replies. I think I've been doing everything OK, and now see how to get the information I've been looking for.
David, I was doing as you say, running the Max SPL tool first, and then setting filters in the Filter Wizard.
After that I was rerunning Max SPL to see if it incorporated the effects of the filters. The rerun of Max SPL appears to default back to unfiltered output.
All I really was looking for was the effect on displacement, given the filters used.
And I now see there is a displacement view selection in the filter wizard...which only makes it easier... perfect.
I'm working on frequency specific limiting, to limit only the frequency region of excess displacement. I can handle driver power limiting easily enough with RMS and peak limiting in my processor.
I'd like not to pull down the entire sub output to address displacement limitations at particular frequencies.
It's a fun processing attempt, using essentially parametric-width notch filters along with a sidechain limiting trigger ....
...and is very much being aided by Hornresp
Consider this ....
Solve for a set of Salmon family horn parameters using the 1st. and 2nd. derivatives of both segments. This will establish the connection point. Then apply the Le Cléac'h method to the Salmon segment to complete the horn mouth. The error at the junction, if any, should be unmeasurable, or certainly within manufacturing tolerances. WHG
Hi Bill,
It's an issue not just confined to Hornresp
Trying to exactly match an oblate spheroidal waveguide segment to a Le Cléac'h segment is a bit like juggling six balls in the air together - not that easy to do.
Getting the Obl mouth area to equal the Lec throat area, the Obl mouth Fta to equal the Lec throat Fta and the Obl mouth radius of curvature to equal the Lec throat radius of curvature all together, is effectively impossible to do.
Kind regards,
David
Solve for a set of Salmon family horn parameters using the 1st. and 2nd. derivatives of both segments. This will establish the connection point. Then apply the Le Cléac'h method to the Salmon segment to complete the horn mouth. The error at the junction, if any, should be unmeasurable, or certainly within manufacturing tolerances. WHG
Dear David, I wonder if there is a way to model these loudspeakers in Hornresp: 34c9 a MDD full range speakers.
There are 9 tubes with different lengths. I am sure it would be too much work to include this kind of model in Hornresp directly - but there might be a trick. I wonder what would be the correct way to create a new driver, which would correspond to 1/9 of the speaker used, then run the simulation 9 times with different tube lengths and then combine the responses in an external program. Intuitively, I would use 1/9 of the Sd - but how would the other parameters scale? Or is this idea way off?
There are 9 tubes with different lengths. I am sure it would be too much work to include this kind of model in Hornresp directly - but there might be a trick. I wonder what would be the correct way to create a new driver, which would correspond to 1/9 of the speaker used, then run the simulation 9 times with different tube lengths and then combine the responses in an external program. Intuitively, I would use 1/9 of the Sd - but how would the other parameters scale? Or is this idea way off?
Hi mark100,
This is intentional - to save me having to do a lot more work
.Kind regards,
David
Hi Bill,
But what about for an OS waveguide, which was the original requirement?
Kind regards,
David
Hi pelanj,
I can't think of an accurate way to model the MMD system in Hornresp. I am surprised that it seems to perform reasonably well. I would have expected it to have a highly "coloured" output - more like a multi-resonant musical instrument, than a hi-fidelity loudspeaker
.Perhaps it works a bit like a log-periodic antenna?
Kind regards,
David
Hi pelanj,
If you would like to experiment along these lines, the Resize Wizard in Hornresp could be used to re-scale the driver parameter values. Another approach could be to use the Multiple Driver Equivalent option in the Loudspeaker Configuration tool. Not sure how valid either of these approaches would be, however
.Kind regards,
David
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Really sorry to see the book arrive in such a beat-up condition
To be honest, I'm not sure if they do. We've had several returns/refunds due to Amazon's poor packaging. We're actually considering finding other retailers and stop selling through Amazon due to that.
The annoying thing is that since I sell the books through Fulfilment by Amazon, I have no control over packaging and shipping, and in addition all the refunds and returns go straight out of my pocket. Amazon has no loss from this.
I would recommend that people buy the book through Lean Business Audio instead (link on the info page in my signature). The shipping is a little more expensive, but it's faster than Amazon and I know it is well packed.
To be honest, I'm not sure if they do. We've had several returns/refunds due to Amazon's poor packaging. We're actually considering finding other retailers and stop selling through Amazon due to that.
The annoying thing is that since I sell the books through Fulfilment by Amazon, I have no control over packaging and shipping, and in addition all the refunds and returns go straight out of my pocket. Amazon has no loss from this.
I would recommend that people buy the book through Lean Business Audio instead (link on the info page in my signature). The shipping is a little more expensive, but it's faster than Amazon and I know it is well packed.
Thanks. I am traveling next week, so I should have some time for tests. I tried to split into 4 as beginning and the impedance plot, when added, is actually quite similar, to what I measure. I think it is not worth of too much effort. For the subwoofer I think I can do with just one tube. Most probably, it is going to be some form of folded TL with EQ.
I think the key lies in the resonance spread. It is funny, but the speakers measure quite flat in a large area of the room.
I think the key lies in the resonance spread. It is funny, but the speakers measure quite flat in a large area of the room.
The sooner the better it would seem.
It is unbelievable that they cannot be held to account for the damage.
Equate the Derivatives ...
of BOTH the Freehafer and Salmon horn segment formula.
This should yield a pair of curves that match at their junction where Rf = Rs
You can also do horn mouths using a Tractrix and Other Curves as well.
If you are willing to incorporate this functionally into your program, I will provide the math and spreadsheet that demonstrates this capability. WHG
of BOTH the Freehafer and Salmon horn segment formula.
This should yield a pair of curves that match at their junction where Rf = Rs
You can also do horn mouths using a Tractrix and Other Curves as well.
If you are willing to incorporate this functionally into your program, I will provide the math and spreadsheet that demonstrates this capability. WHG
Thanks Bjorn and Thomas for publishing this book. I just received mine and it looks wonderful. I might skip over an equation or two
I ordered my from Amazon (warnings came too late for me) so I would also recommend the alternate supplier. The UK warehouse fell short of adequate packaging and the intermediate couriers had to tape the box back together. All is good in the end.
Hi Bill,
Yes please!
A spreadsheet that can generate a chart showing an OS waveguide seamlessly transitioning to a 180 degree Le Cléac'h profile mouth termination, would be really excellent.
Thanks and kind regards,
David