What is the vertical scale?
Can you do screenshots instead of photos ? (press the "print screen" key on the top right side of your keayboard, and then paste into paint brush and save)
http://www.wikihow.com/Take-a-Screenshot-in-Microsoft-Windows
Can you do screenshots instead of photos ? (press the "print screen" key on the top right side of your keayboard, and then paste into paint brush and save)
http://www.wikihow.com/Take-a-Screenshot-in-Microsoft-Windows
I mean that the response will suffer a lot of interference and will make comb filter response, and there for wil not measure constant pore linearity behavior.
He has a hand held unit, afaik? No?
Anyhow Angelo, measure at <1m from each horn, not at 2m.
Imo that is too far away, that will dump in the room too strongly, and floor bounce is
still an issue at that distance...
Why do you not use one of the freeware computer based FFT softwares suggested?
You would get much more useful information.
Does that box you have now give you a "line out" where you can just get the sound from the microphone?
But actually, almost any microphone will get you decent relative results... and again, those Panasonic Electret mics that cost ~1.00USD work just great... imperfect above 10khz... but you don't need perfection yet.
_-_-bear
Anyhow Angelo, measure at <1m from each horn, not at 2m.
Imo that is too far away, that will dump in the room too strongly, and floor bounce is
still an issue at that distance...
Why do you not use one of the freeware computer based FFT softwares suggested?
You would get much more useful information.
Does that box you have now give you a "line out" where you can just get the sound from the microphone?
But actually, almost any microphone will get you decent relative results... and again, those Panasonic Electret mics that cost ~1.00USD work just great... imperfect above 10khz... but you don't need perfection yet.
_-_-bear
Just buy a EMC8000 45 euro is 65 dollar
An externally hosted image should be here but it was not working when we last tested it.
And a 24bit sound-card with phantom supply
An externally hosted image should be here but it was not working when we last tested it.
Or use the soundcard of your pc and only buy a phantom power mic preamp. 33dollar.
http://www.ebay.co.uk/itm/QTX-SOUND-CONDENSER-MICROPHONE-PHANTOM-POWER-SUPPLY-UNI-/270813635501?pt=UK_AudioElectronicsVideo_Video_TelevisionSetTopBoxes&hash=item3f0dc023ad#ht_1321wt_907
And download for free.
http://www.fesb.hr/~mateljan/arta/
So you can do professional measurements for a investment of 98 dollar.
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I don't think the contribution of the coffee table in Angelo's setup is necessarily all that detrimental since it doesn't appear like it is in a position to provide a strong first order reflection from his speakers at the listening position. It may be diffracting as much as reflecting at the listening location in this instance as a result of its edges. Even so, I'm not sure I'd be very comfortable with such a large reflective surface in that particular location.
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I sort of discounted the whole RTA measurements because the system really doesn't have the resolution to discriminate in enough detail and...
I would also question the measurement because of floor bounce and other early return reflections, which there is no evidence that was considered in the measurement process.
To get meaningful data requires a more dedicated test setup such as HolmImpulse, mic, and a sound card. Then, there is utilizing proper measurement procedures and techniques. Without that the collected data can be very misleading.
i bought this audio analyser :
PC USB Real Time Audio Analyzer
hope that will help to make more accurate measurements.
PC USB Real Time Audio Analyzer
hope that will help to make more accurate measurements.
Did you just purchase this?
If so, I would consider canceling the order.
Instead, I would buy:
1. Behringer ECM8000 mic $65
2. M-Audio Mobile Pre USB $160
Download HolmImpulse for free. It is much better suited to measuring speaker response.
You can also download the free version of Praxis by Liberty Instruments, which will do all the same RTA measurements as what you bought and it will also do Theile/Small measurements of drivers, if memory serves.
The real time analyzer is good for understanding the room, but not much good for analyzing your speakers. HolmImpulse is exactly what you need and it is free. It also does phase measurements and gating.
Yes, i bought it. I bought some time ago a mic similar to the Behringer, Paudio usb, and pre-mic, but there were things to solder aditionally, and components to buy, which i were not able to find locally. So i gave up. The virtins seems a ready to go solution, that is more important to me, than additional Thiele/small measurement possibility etc.....
I was not clear. A RTA system will not analyze your speakers, only the room.
To resolve the issues with the speakers and their crossover requires different tools and a different approach.
The tool you have will not do that. At least, not to any degree of precision.
However, you can download HolmImpulse and see if it recognizes the USB adapter and mic that came with the RTA system. If it does then you are good to go.
It is better not to advise you know better. Ever heard of MLS?
Tried it out - got it, thanks for the advice. Next display,i will take a screenshot, and show it.
that ?
ScopeDSP: FFT Spectral Analysis Software for Windows | Iowegian International
isn't that rather complex to understand ? I am starting from 0, so the easyer to understand, the better.
ok. i wrote virtins. lets see if HolmImpulse can be used with the RTA i bought. i did not make a indepth research, but virtins seems a ready to go solution. A few years back i tried to follow advice of this website :
Measuring Frequency Response Using ARTA
actually bought mic, usbtransit soundcard , pre mic, but had to build a simplified jig to do impedance and T/S measurements. Since i did not find a 10ohm resistor and other componentes locally, i got dismotivated, and put the idea on side.
The table is a non issue for me. It does not change anything to the fact, that the S2 sounds colored. But measurements yesterday and today gave me already some clarification. I will give a try, and cross S2 and the Fane differently, and see what happens.....
You don't have to build the jig, just use HolmImpulse with the USB Transit, the preamp, and the mic and you are good to go.
That will let you get the frequency and phase information, which is important to see what you have now.
The jig can be made with Radio Shack test leads and a resistor. You know, the ones with alligator clips. Just make sure you get a good contact. You can solder the wires for better performance, but you don't need to make a whole box for the jig.
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The LX500 is going to run you about $2,500.
You can get comparable functionality from ARTA for under $100 plus the cost of USB audio interface and a good mic.
If you go all out and get a calibrated mic for $100 and a good USB or Firewire audio interface for $200, you max out at $400 for everything.
For the DIYer I don't know if you would ever notice the difference.
I should add that you could substitute SoundEasy for ARTA for an additional cost of $150 and get a nice box design and crossover design software for a complete package. Total outlay would be $650.
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I think ARTA is fantastic, and as far as measurements go it will do almost anything you can image, including room measurements (RT60, ETC and so on) as well as speaker measurements.
Probably the best bang for the buck non-free measurement-only software out there, and with a full featured (minus save) unlimited time demo. The learning curve could be a bit steep for those first starting out with impulse based measurement though, and it doesn't combine any design features such as integrated crossover optimizers or baffle diffraction simulators etc.
Holm Impulse looks quite decent, and is a bargain for something free, in many ways its a cut down much simpler version of ARTA (with a lot less features) and although it looks simpler on the surface, I've actually found it a bit confusing to use. There are certain manipulations I do all the time in ARTA that I find quite cumbersome in Holm Impulse but that could be because I learnt ARTA first. Still a good starting point for those new to impulse measurements though, when it's free.
Does anyone have any links to a good primer guide on impulse based gated measurement techniques ? I think its easy for those of us that have beaten this path before to be critical of measurements made the "wrong" way, but it really isn't obvious to anyone first starting out measuring speakers why a steady state (RTA 1/3 octave bands etc) measurement made in a room is wrong, nor is it easy to grasp at first how a gated measurement works, what it is capable of doing, and what its limitations and trade-offs are.
It's just as easy to screw up gated measurements if you don't understand the concept of a reflection free time window, and the time/bandwidth limitations of a given gate time. (Lowest possible measurement frequency, and the loss of resolution in the 1-2 octaves above that) A link to some sort of primer on the hows and whys of gated impulse measurements would be very helpful I think, more than just saying "do it this way". The manual in ARTA is a bit too technical, but perhaps the Holm Impulse manual has a good intro ? (I haven't read it)
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Folks,
the multiinstrument software included in the virtins package seems to be quite capable and the data can be exported, so what is missing (for example waterfall plots ) could be done by additional software.
It has some advantages to purchase a complete package provided by one supplier as it should work from the beginning, and to have some support if something does not work.
the multiinstrument software included in the virtins package seems to be quite capable and the data can be exported, so what is missing (for example waterfall plots ) could be done by additional software.
It has some advantages to purchase a complete package provided by one supplier as it should work from the beginning, and to have some support if something does not work.
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