How do we export .FRD files from HOLM?
Nevermind, I just need to export the txt file and rename it FRD
Nevermind, I just need to export the txt file and rename it FRD
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Right. But you may want to scale it up by 80-90dB before you export. Depends on where you are going with it.
Yeah, you can add up to 99dB in the options window of each measurement (A, B, C). The graph will go right off the chart, but it exports fine. Put it back after you export to see it again on the HOLM chart.
Who was it that figured that one out? It's back in the thread somewhere. Major kudos to him!
Who was it that figured that one out? It's back in the thread somewhere. Major kudos to him!
HOLMImpulse and EMU-0404 Calibration
I am using trying the software for a few weeks, and liked it very much. I have tried with several sound cards but an external one seems the best.
Is there anybody tried sound card calibration for EMU 0404?
I'm using Behringer ECM8000 connected to EMU0404 and doubtful about loopback connection.
Should I disconnect the mike and connect a cable between input and output of the sound card? Is that enough?
Thanks.
I am using trying the software for a few weeks, and liked it very much. I have tried with several sound cards but an external one seems the best.
Is there anybody tried sound card calibration for EMU 0404?
I'm using Behringer ECM8000 connected to EMU0404 and doubtful about loopback connection.
Should I disconnect the mike and connect a cable between input and output of the sound card? Is that enough?
Thanks.
Setting voltage to speaker
I will be using the software shortly, but how do you set the output to 2.83 volts since I don't see a place to calibrate the voltage. Or does it do it automatically when doing the calibration. I will be using this jig
http://www.diyaudio.com/forums/mult...device-arta-speaker-workshop-holmimpulse.html. So what steps are needed in getting things set for measurements.
Thanks
I will be using the software shortly, but how do you set the output to 2.83 volts since I don't see a place to calibrate the voltage. Or does it do it automatically when doing the calibration. I will be using this jig
http://www.diyaudio.com/forums/mult...device-arta-speaker-workshop-holmimpulse.html. So what steps are needed in getting things set for measurements.
Thanks
Since Holm does not know the gain of anything following it or input to it, it cannot know what 2.83 volts will be nor what the SPL is. You will need an SPL meter to calibrate it if you want absolute levels.
gnal: You want to do a loop from output to input to calibrate. If you can use the mic input, you should. I can do so on my M-Audio card by using the "Pad" on the mic input to bring down the level. I use a 1/4" to XLR cable for this.
McMahon. Not likely your soundcard will output 2.83 volts. And it wouldn't drive the speakers anyway. So... You set the output level of HOLM to -3dB or -6dB and then adjust your amplifier to give you 2.83 volts, or whatever you want. I don't worry about that, I just set the MLS signal (like pink) to give me ~84dB as measured with the Radio Shack SPL meter. That's a good measurement point for me.
McMahon. Not likely your soundcard will output 2.83 volts. And it wouldn't drive the speakers anyway. So... You set the output level of HOLM to -3dB or -6dB and then adjust your amplifier to give you 2.83 volts, or whatever you want. I don't worry about that, I just set the MLS signal (like pink) to give me ~84dB as measured with the Radio Shack SPL meter. That's a good measurement point for me.
Ditto - absolute calibration of level is too hard to setup and unnecessary. I do it just once for a speaker system to note the system sensitivity using a SLM. Everything else is simply done in relative terms - don't change any gains outside of Holm and everything stays calibrated to each other.
And I ditto your ditto!
It's all pretty easy to use.
Earl, do you use any particular SPL, or just whatever is convenient? I went from "whatever" to trying to keep things at about 84dB. This seemed like a good average listening level for me, so the system is working in its normal range. Not sure how much it matters, as long as S/N is good and it's not overdriving.
Your thoughts?
It's all pretty easy to use.
Earl, do you use any particular SPL, or just whatever is convenient? I went from "whatever" to trying to keep things at about 84dB. This seemed like a good average listening level for me, so the system is working in its normal range. Not sure how much it matters, as long as S/N is good and it's not overdriving.
Your thoughts?
The higher the SPL the better the SNR, but too high and nonlinear effects creep in and then the SNR goes down. 84 dB seems way too low for me. I'm more like 90-100 dB, but then efficiency enters into this equation. My speakers are still loafing at those levels, yours probably not.
Really? I'd think there would be a significant difference tripling the distance. Very small room?
Horns. 😉 Room volume somewhere around 4000 cubic feet. Mid size.
Yeah Earl, I've often run hotter, like the 90-100dB range. That's about a watt, RMS. Just can't decide if one is better than the other. I do wear ear muffs at the higher ranges, tho! Gets darn annoying without.
Yeah Earl, I've often run hotter, like the 90-100dB range. That's about a watt, RMS. Just can't decide if one is better than the other. I do wear ear muffs at the higher ranges, tho! Gets darn annoying without.
So when measuring higher sensitivity designs we should keep it around 100dB to get the most accurate readings?
