I've read so many posts of people having a hard time with REW , sound card and RS meter.SAC said:Start out with RoomEQWizard.
Especially as you state that you are a beginner, if and when you outgrow its capabilities or need additional features, you might then consider products like ARTA or EASERA (and I would seriously suggest downloading their manuals for use as additional tutorial resources).
ARTA is a 'best buy' and EASERA is a comprehensive package that integrates well with other more specialized industry standard analysis and design components - albeit at a much higher cost of entry.
Short of making the jump to those professional products, REW is hard to beat for the capabilities and its cost - free! The products you mention not only cost more, but do not provide as comprehensive a list of features as REW. Plus you have the benefit of online support here on this forum.
Just wanted to measure in room response of my current 5.1 system
That is exactly why I asked. You can get FR measurements equally rapidly with either XTZ or Omnimic. There is more generous guidance with XTZ but OmniMic can do more if you know what to do and can interpret the help files. Why don't you download the help/docs and see if they are revealing to you?I've read so many posts of people having a hard time with REW , sound card and RS meter.
People using OmniMic said they could get in room FR measurements within minutes ??
WOW!, that was intense for a beginner, but thank you for taking the time !!OK, I'll play devil's advocate for a few minutes - don't panic...:laugh:
So you are willing to pay $300 for just a frequency response and a fancy SPL meter? Are you kidding me?
And it doesn't even offer time domain measurements!
And you actually have a practical use for an oscilloscope and higher order distortion components?
As far a problems, remember that you are on a support site. This is a place where people who do not understand the basic hardware configuration, functionality of the tools or what the measurements mean come for help. Your concern is like going to the emergency room and drawing the conclusion that since many injured people go there that all of the population must be experiencing the same problems!!
But the vast majority of folks don't need to come here!
And the compatibility problems you are worried about are not limited to REW. They are common to many PC and Mac based IO systems (especially as the Mac is nothing but a PC in terms of hardware - literally - as it is the latest incarnation of the Intel Roadmap.)
And since I am on a roll, why stop there...:laugh:
Many are preoccupied with calibrating a mic. But don't dare ask them why they are preoccupied with this, as they are not measuring anything against some ideal standard, nor do any of their measurements require calibration such as do Noise Level Analysis (NLA) studies that are to be entered into evidence in court hearings!
Quite frankly, mic measurements are relative for most measurements. And mic calibration is a relatively easy thing to do - especially if you start with a quality mic - for which most have supplied calibration files! But instead many start with the cheapest mic they can find and expect to make it world class by calibrating it - hardly the smartest strategy.
And SPL levels? They are relative for all practical purposes! But then some will buy a RS SPL meter and simply assume the RS SPL meter to be calibrated reference standard and to be more calibrated than other sources? Really?? :rofl:Its amazing how many are appeased by assumptions and appearances!
The irony is that the ONLY calibration that is necessary is that of a simple hardware propagation delay/latency physical loopback or file in order to account for the time delay of the signal through the associated hardware for when making time based measurements. And most folks (preoccupied with mic calibration) ironically totally ignore this procedure!
OK, now that I have had a bit of fun ( and I hope no one is too offended if I hit a bit close!)...the point is that REW is exceptionally easy to use! If you are trying to use odd Firewire devices on a Mac, you may have trouble, as Apple's support there is amazingly limited. Likewise with some of the various Firewire chipsets and hybrid USB/Firewire adapters - this issue is common throughout the entire computer based data acquisition industry - and a fault of some of the hardware manufacturers - certainly not REW!
So what's the answer? Simple. Perform a bit of due diligence and investigate interfaces/pre-amps that work/do not work without problems - and there are MANY that work! Do this BEFORE you sink money into the platform! And then spend a bit of time to familiarize yourself with the tools and also with what information the various measurements provide as well as how to interpret the various measurements. There IS a learning curve. But it is not difficult! And in learning this, you will learn ALLOT about the science of acoustics the will enhance your understanding and your awareness of how to use and apply the insight provided by the tools which will then increase your productivity!
Oh, and one last thing... To invest in a measurement and analysis platform and to not get the various significant time domain tools, is in my opinion a waste of money! As the single most significant advancement in the field of acoustics in the past 40 years has been the advent of time domain measurements and the information/insight they provide! And if you are not aware of this now, PLEASE take the time to discover the significance and practical utility that they provide! You will NOT regret the effort!
The fact is, REW may be the best 'deal' in acoustical measurement software available today. There are larger and more expensive packages, but few provide the wealth of practical options and utility at such a tremendous value! John has indeed provided folks with a tremendous service!
Don't let the fact that you have discovered a source of product support scare you away from the MANY very happy users of the tools! And at the very least, give it a try - THEN, if it doesn't do what you need, then consider spending allot more money - and still facing the same compatibility issues with IO hardware and IO drivers, pre-amps and PC/MAC platforms!
(Oh, and while becoming familiar with the measurements, also become aware of the distinction between large and small acoustical spaces and the acoustical principles that characterize each - perhaps the biggest significance being that RT (reverberation) calculations are not of use in a small acoustical space! For more info see Sound System Engineering, Davis and Davis, 2nd ed. or Davis and Patronis, 3rd ed.))
Also, if you PM me with you email address, I will send a chapter featuring an overview of many of the measurement tools, including time domain measurements...
In comparing the various platforms, one significant feature jumps out. REW includes time domain response views (impulse response and envelope time curve (ETC), where many others do not. And for acoustics this is IMPORTANT. Thus, as compared to the frequency response which simply shows you a derivative non-causal lumped-together result of the interaction (superposition) of many discrete direct and indirect signals (often simply referred to, however inaccurately, as ‘reflections’); by using time domain response tools such as the envelope time curve or ETC, the time domain allows you to see all of the specific direct and indirect specular (focused) signals , and to determine each one’s gain, arrival time, direction, persistence, etc. such that one can then effectively address each discrete signal individually with respect to the others via the use of varying treatment options in order to effectively remediate issues and to ultimately tailor a quality listening space. A complex way to say that we can see each ‘reflection’, identify problems, and correct them in a way no other perspective allows.
It is specifically this 'new' ability to see the detail of the behavior of sound that allows us to specifically 'treat' a room' (and much more). Thus, by analyzing the behavior, one can surgically treat the problem causing specular signals and effectively tune a room so that the signals work together in a constructive manner, rather than causing problems. And this level of detail IS necessary, as the notion of simply applying a bunch of absorbers and maybe going further and simply adding some diffusors is NOT the solution! Treatment must be surgically targeted to solving specific problems - not simply eliminated 'reflections'!!!! Just as a surgeon does not simply remove a bunch of organs in the hopes of solving an illness, one does not indiscriminately just add room treatments thinking that this will solve a problem! But let's face reality - as this is what far too many do! Thus, the power of these tools is that you can now - with a bit of awareness of acoustic response models (the results you want) and knowledge of just how the treatments function - surgically solve the real problems, without causing more or simply moving the problems around!
This feature is critical to both speaker analysis, speaker alignment (both in terms of loudspeaker component drivers and crossovers) AND with regards to the signal alignment of multiple loudspeakers, as well as to analyzing speaker-room interactions that define small room acoustical behavior.
I realize that some are thinking - what is he saying? I understand. I apologize for much of this being stated in a somewhat less than casual manner - but I also tried to make the descriptions sufficiently accurate without simply resorting to techno-term shorthand should one wish to delve deeper into the subject. Instead the seemingly complex adjectives and adverbs are meant to reasonably qualify the descriptions so that they provide a reasonable behaviorally based description that one might otherwise need to read several chapters to obtain (especially as we lack clarifying illustrations here!) - after which one could instead simply use a few techno-babble terms assuming you already understand the implied qualification! Hopefully, for those willing to dissect the descriptions, this will provide you with a 'Cliff's Notes' version that might help point you in the proper direction for further investigation. Otherwise, if you care and the descriptions are too confusing, don't panic! PM me and I will be glad to explain things at whatever level you are comfortable and/or recommend specific resources for further investigation.
Yep...:neener: But only for a little whileFolks, yes a few are initially confused.
(BTW, as a preface, I respect everyone's ability and right to make a choice - and even to be incorrect!!:sarcastic: I just don't want anyone to spend to much and end up limiting your choices and capabilities in areas that are VERY important acoustically!)If you are completely new to acoustical measurements and don't want to spend the time figuring out how to use the software and determining which sound card and mic to buy then XTZ or Omnimic is the best solution IMO. Most people's room issues are low frequency related and very difficult to identify and resolve without high resolution time domain measurements (which XTZ includes via a spectogram). It is possible to get away with not having an ETC since visually with the aid of a mirror you can tell where the reflection points are in any room. And nearly all rooms that we use for audio or home theater will need treatment at these mirror points. I agree it is not ideal and I have requested from XTZ on a number of times to include an ETC but there is a very usable workaround.
I actually find XTZ easier to use for dialing in EQ as well since it offers a unique 'stimulus EQ' mode which allows you to create filters in the XTZ software and remeasure with those in the chain thus you can go quicker than if you had to download them to your external EQ box each time as you would have to do with REW.