The 64 bit version works fine on my 64 bit Vista machine which is now Win 7 64 bit.
Need Help Using HolmImpulse
Being pretty new to computer loudspeaker testing (and to speaker testing in general) I have a few questions about HolmImpulse. I’ve had only mixed success with this very intriguing program so far, but I think I still need to refine my testing technique. So, please be patient, but I have a few rookie questions:
1) What is the “flip frequency” that is used to set up the Square noise (MLS) test? I’m just curious about this since the default setting (.900) seems to work. I accidentally changed this to .999 once and the test signal started to sound very peculiar! I’d like to know what I did.
2) Can anyone, in 25 words or less
, explain why and when I should select either logarithmic sine sweep, chirp and/or the square noise as my signal. I have tried all three on numerous occasions, and their results are almost never the same, although they do track to a certain extent in certain frequency ranges, depending on whether I am making near field or far field measurements.
3) I am also curious if there are any guides as to which type of smoothing I should use and when to use them. It seems I can turn a very ragged response into a very smooth response, clearly one can go to far with smoothing, but I don’t have good feel (ok any) for how far is too far.
I haven’t found, yet, answers to these particular questions in Testing Loudspeakers (by Joseph D’Appolito)—great book by the way—so I am appealing to the forum for help.
I would also be interested in hearing from anyone who is using an EMU 0202 USB with HolmImpulse. HolmImpulse always crashes when I close the program and occasionally during program operation. I suspect that the problem is the 0202 since if I don’t go above 44.1 khz I avoid most crashes during operation; I also think its drivers, are generally, pretty flaky. Unfortunately, Creative’s support leaves much to be desired.
TIA
Terry
Being pretty new to computer loudspeaker testing (and to speaker testing in general) I have a few questions about HolmImpulse. I’ve had only mixed success with this very intriguing program so far, but I think I still need to refine my testing technique. So, please be patient, but I have a few rookie questions:
1) What is the “flip frequency” that is used to set up the Square noise (MLS) test? I’m just curious about this since the default setting (.900) seems to work. I accidentally changed this to .999 once and the test signal started to sound very peculiar! I’d like to know what I did.
2) Can anyone, in 25 words or less
, explain why and when I should select either logarithmic sine sweep, chirp and/or the square noise as my signal. I have tried all three on numerous occasions, and their results are almost never the same, although they do track to a certain extent in certain frequency ranges, depending on whether I am making near field or far field measurements.3) I am also curious if there are any guides as to which type of smoothing I should use and when to use them. It seems I can turn a very ragged response into a very smooth response, clearly one can go to far with smoothing, but I don’t have good feel (ok any) for how far is too far.
I haven’t found, yet, answers to these particular questions in Testing Loudspeakers (by Joseph D’Appolito)—great book by the way—so I am appealing to the forum for help.
I would also be interested in hearing from anyone who is using an EMU 0202 USB with HolmImpulse. HolmImpulse always crashes when I close the program and occasionally during program operation. I suspect that the problem is the 0202 since if I don’t go above 44.1 khz I avoid most crashes during operation; I also think its drivers, are generally, pretty flaky. Unfortunately, Creative’s support leaves much to be desired.
TIA
Terry
I think I might be able to answer some, but not all.
Use log sweep if you can. I.E. low noise or close. Use MLS for noisier environments or farther away. Chirp - have not figured that one out yet.....
Smoothing. Anything between 3rd and 12th is useful. 3rd give you a sort of general look at tendencies. That's handy. 6th or 12th shows you more detail, sometimes more than you can do anything about. Unless you have an almost perfect set-up, 12th is a jaggy as you want to go. I usually work in 6th, unless I'm looking for some little detail somewhere.
Can't say about the sound card. I rarely have crashes with my M-Auio USB card, but even its drivers are flaky. HOLM does not seem to care, tho. Maybe stop the audio stream before quitting?
Use log sweep if you can. I.E. low noise or close. Use MLS for noisier environments or farther away. Chirp - have not figured that one out yet.....
Smoothing. Anything between 3rd and 12th is useful. 3rd give you a sort of general look at tendencies. That's handy. 6th or 12th shows you more detail, sometimes more than you can do anything about. Unless you have an almost perfect set-up, 12th is a jaggy as you want to go. I usually work in 6th, unless I'm looking for some little detail somewhere.
Can't say about the sound card. I rarely have crashes with my M-Auio USB card, but even its drivers are flaky. HOLM does not seem to care, tho. Maybe stop the audio stream before quitting?
Need still more help with HolmImpulse
Thank you skeptic43, panomaniac and breez. Another question. I have been measuring near field response in a small, vented speaker that I have built. The nearfield response of the woofer does not show the notch, that a vented speaker should show. The impedance curve I measured with WT3 looks textbook so I can't figure out why the response shows just a small inflection at fb, not at ll what I would have expected from D' Apollito. I figure I must be doing something wrong-but can't quite figure out what. Again any suggestions would be very much appreciated.
Thank you skeptic43, panomaniac and breez. Another question. I have been measuring near field response in a small, vented speaker that I have built. The nearfield response of the woofer does not show the notch, that a vented speaker should show. The impedance curve I measured with WT3 looks textbook so I can't figure out why the response shows just a small inflection at fb, not at ll what I would have expected from D' Apollito. I figure I must be doing something wrong-but can't quite figure out what. Again any suggestions would be very much appreciated.
Attachments
I agree with you ilardi about D' Apollito's testing book. Great detail on how to do the testing but, and a VERY important but - little or nothing about interpreting test results.
D' Apollito did a long series of technical reviews of kit loudspeakers is Speaker Builder / AudioXpress magazines. In the reviews he analyzes his measurements. He found a suppressing number of design faults!
Thanks. However, my point was he should have included that stuff in the book for completeness.
I think it would be difficult to have provide interpretations of all potential issues. But a case in point-in support of skeptic43-is that the book, which I do use and enjoy, doesn't teach the analytic tools that would help me figure out what is going on with the measurements in my post 126. In fact, I have kind of come to the conclusion that it is not my measurement technique but rather mistakes I have made in the design of this particular prototype. But the book didn't point me to that conclusion at all. In defense of the book, however, the author does provide some useful guidance for interpreting impedance curves.
I think that you are right. I bet he planned on doing so, but somewhere along the line he ran out of time or enthusiasm.
Attach the measurement file.zip
Hi, can you attach the measurement as a file.zip
HOLMImpulse > File > Save Measurements
Then I can see your settings
Hi, can you attach the measurement as a file.zip
HOLMImpulse > File > Save Measurements
Then I can see your settings
when i bought his book it wasnt deliverable at first - the reason was: "he writes a new one..."
i asked twice, but nevertheless ordered Testing loudspeakears cause i needed it at this moment.
i´m very happy with this book. the dislikes are the same as from the others, no comparisons. but hey.. revolutions are no childrens birthdays
(holmimpulse is on the way to it btw) maybe with the next book we will get the all inclusive solution.First time post here. I have never measured any speakers before, but would like to just get a Freq. Response Graph for my 3 Way speaker system.
I downloaded the HOLMImpulse software on the recommendation of someone on one of my Audio Forums. I am very Computer Savvy as that was my profession. However, Even though I have been involved with Audio for 30 years, my audio knowledge is probably at the neophyte level compared to all of you here. I have never measured the Freq. Response of my Speakers, but have built some crossovers based on Calculators.
I downloaded the User Guide and was looking for some very basic Instructions on how to use this program. In terms of the hardware that I need to set it up and what functions to run in HOLMImpulse to get some very basic freq. Measurements and start learning from there by doing. Nothing in the User Guide seems to address the basics.
Are there any of these instructions available in text or in help form on the program? I am guessing that I need an External Sound Card, A microphone, some cabling, And my amplifiers, pre-amplifers and my Laptop. I do have an EX-TECH SPL that has some jacks on it, that could be used as a Microphone in some Measuring software (Not sure if HOLMImpulse is one of those) - Recommended Hardware would be a plus as I do not have an external Sound card yet or Microphone etc. I don't mind spending some money on this, as I really would like to be able to do this. Just for my personal Audio Hobby.
Any help from you will be appreciated.
I downloaded the HOLMImpulse software on the recommendation of someone on one of my Audio Forums. I am very Computer Savvy as that was my profession. However, Even though I have been involved with Audio for 30 years, my audio knowledge is probably at the neophyte level compared to all of you here. I have never measured the Freq. Response of my Speakers, but have built some crossovers based on Calculators.
I downloaded the User Guide and was looking for some very basic Instructions on how to use this program. In terms of the hardware that I need to set it up and what functions to run in HOLMImpulse to get some very basic freq. Measurements and start learning from there by doing. Nothing in the User Guide seems to address the basics.
Are there any of these instructions available in text or in help form on the program? I am guessing that I need an External Sound Card, A microphone, some cabling, And my amplifiers, pre-amplifers and my Laptop. I do have an EX-TECH SPL that has some jacks on it, that could be used as a Microphone in some Measuring software (Not sure if HOLMImpulse is one of those) - Recommended Hardware would be a plus as I do not have an external Sound card yet or Microphone etc. I don't mind spending some money on this, as I really would like to be able to do this. Just for my personal Audio Hobby.
Any help from you will be appreciated.
What You Need
You'll find the HOLMImpulse a great software and easy to use once you get it running.
Stuff you need.
That's about it. Of course there are other ways to do it, but this is pretty simple and all off the shelf. Please ask if you have further questions.
You'll find the HOLMImpulse a great software and easy to use once you get it running.
Stuff you need.
- Microphone. Many of use use the Berhinger mic Or the Dayton mic which is pretty much the same thing.
- Mic stand. Find online or at any music shop
- XLR mic cable
- Mic preamp with phantom power.
- Sound card. M-Audio and others make USB and Firewire cards that have the mic preamp and phantom power built in. That's what I use.
- Drivers for the soundcard. If it has ASIO drivers, use those.
That's about it. Of course there are other ways to do it, but this is pretty simple and all off the shelf. Please ask if you have further questions.
Thanks for your reply!
Is USB 2.0 fast enough or should I get a Firewire Connection?
Thanks for your reply!
Is USB 2.0 fast enough or should I get a Firewire Connection?
Holmimpulse works fine even with USB 1.1.
/Andreas
Thanks for all your replies!
I have a question on the microphone. I have an Extech 407727 SPL meter. I have heard that it is possible to use an SPL meter for a Microphone on some measuring software. From the manual:
Analog Output:
A 3.5 mm phono output jack is provided on the meter for connection to external test equipment. An AC rms voltage is provided (0.707v maximum) which is a linearized representation of the analog pointer reading. Connect this output to a datalogger, chart recorder, etc. for datalogging purposes.
I don't mind buying another microphone, if it will work better, but If this will work just as good, I might as well save a few bucks.
As far as the external soundcard, is there a certain desirable model to have? Or doesn't it make much difference? I don't mind spending a few bucks here either, if it makes some sense.
I have a question on the microphone. I have an Extech 407727 SPL meter. I have heard that it is possible to use an SPL meter for a Microphone on some measuring software. From the manual:
Analog Output:
A 3.5 mm phono output jack is provided on the meter for connection to external test equipment. An AC rms voltage is provided (0.707v maximum) which is a linearized representation of the analog pointer reading. Connect this output to a datalogger, chart recorder, etc. for datalogging purposes.
I don't mind buying another microphone, if it will work better, but If this will work just as good, I might as well save a few bucks.
As far as the external soundcard, is there a certain desirable model to have? Or doesn't it make much difference? I don't mind spending a few bucks here either, if it makes some sense.
Thank you Ask. Unfortunately, when I go to save the file I get an "Unhandled Exception..." and the file that is saved has 0 kb. (I also get an unhandled exception whenever I quit the program). I've reinstalled HolmImpulse several times but I still get this whenever I quit the program.
Attached is a text file into which I have pasted the details of the unhandled exception.
Thanks in advance for any suggestions you can provide.
Terry
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