The "Official" xtz Room Analyzer Thread - Page 5

Seeking advice. I don't need the most flexible, sophisticated measuring system out there, I'd just like to do some measurements in my room to evaluate sub placements, room treatments, etc. I don't have a cal file for any of my current mics and am unwilling to spend many hours learning software and getting pieces of equipment to work properly. So REW does not look good to me. I am considering XTZ or OmniMic. I feel confident with Kal's review of XTZ but have also heard that the "new kid on the block" OmniMic (coincidentally the same price) may offer advantages. I'd like some unbiased input as to the plus/minuses of these two for the casual user. Advice? Does it matter? TIA

The ONLY advantage of XTZ to OmniMic ( used to own XTZ and now own OmniMic) is that XTZ has a much simpler chart to look at bass ringing. Other than that, no contest, not even close. (IMHO)

I haven't used Omnimic, but I've been thinking of upgrading to something better from XTZ because I'm a bit frustrated with the lack of additional features or any sort of innovation from them.

I'd also like to be able to measure below 16hz, and you can't with XTZ. Been thinking of getting a nice calibrated mic and going back to REW. But in defense of XTZ, it is a total no brainer to use.

Thnx, I'm trying out OM myself now.

I have posted some feature requests for XTZ RA here http://www.avforums.com/forums/xtz-f...dback-xtz.html
anyone else got any other suggestions?

The XTZ analyzer is on sale right now for $239.99 at acoustic frontiers. I just ordered one and time for me to play with it next week. FYI.

Things to come... XTZ Room Analyzer II and XTZ Room Analyzer II Pro!
Also, good news is that the new II Pro software is also compatible with the old microphone and can be downloaded from the XTZ website now!
http://www.xtz.se/uk/support/file-archive

Is this software that we can simply download for our existing XTZ, or is it a new product one needs to purchase?

Here's a .pdf showing the new model II and capabilities. Nice improvements if the software will play with the older model.

http://www.xtz.se/download/?FILE_ID=...PRO_ver2_3.pdf

Not entirely true. If you want to do room measurements then XTZ is fine but it falls way short when it comes to speaker design measurements.

Also XTZ does not measure below 18Hz??

Last part, OmniMic is part of the community!! The author is a DIYer and a contibutor on this forum and PE's forum. I see no reason not to support our own people. I would go further to say, why not support an American made product over a foreign choice??

When I looked at XTZ I found it lacking in many things I required. I never looked back when I have free software like HOLM,ARTA and REW.

What Mics do you have and what are you trying to do? There is a great thread in the DIY section showing many mics do not really need special calibration when it comes to measuring bass response in room.

If I was to buy an all in one solution. Its an easy choice for me, it would be OmniMic.

1. OmniMic author is very active member on forums, requests are worked on.
2. PE also has a great support system in place and there are two big communities that use OmniMic so you have forum support.
3. Buying OmniMic support the US economy (if that matters to you, it does not have too).
4. There is nothing that the XTZ does that OmniMic can not do, measuring down to 10Hz or below might matter to some also.

Is PE parts express?

Thanks

The II and II Pro have new microphones which are better than the old one.
The old one is +/- 3dB, the new one is +/- 1dB.

BUT, like I said, you can use the old mic with the new II Pro software.
XTZ even said so and I tried it and it works fine.

16 Hz.

Here is some of the new functionality.
You can drag the sliders marked in red, bottom left, to change the curves
displayed on top. There is also an "Auto-Align" button down to the right.
From the brochure:

phase settings can be made.

Hi, thnx for the response. I have several decent condenser mics, including two Behringer ECM8000 mics (one supplied with each of my Velodyne DD10 subs, no cal file provided or available from Velodyne). I'm not sure if a generic cal file is available for free download anywhere (or if that would be of much use) but I believe it costs around $100 to have one calibrated, not much different than ordering a new one with cal file. I also have an Audyssey Pro calibration kit mic, which has a cal file provided but it is proprietary and not usable outside the Pro software). I also have a Groove Tubes GT55 (Studio FET recording mic with no cal file). I have gone ahead and done what I could with the tools at hand...

My first task was to optimize placement of my dual subs taking into account their simultaneous output interacting with room nodes. Each sub has an internal SMS system designed to measure that sub's response in room. I figured out a way to do a sub crawl using one sub's test tone to test both subs at the same time. I ran the tone to the AVR, as usual, and then simply split the sub channel output signal to both subs. A real-time response graph is shown on the TV display as one manhandles the subs around. I ended up placing the subs midpoint on front and back walls.

As a baseline, I then ran Audyssey Autosetup calibration on my Denon A100 which has MultEQXT32 using the Denon supplied standard cheapy Audyssey mic (+/-2dB, internal cal filein the AVR). XT32 first pings the subs individually for distance and level, then EQs them together. End result sounded pretty good. To take full advantage of Audyssey, I then used the Audyssey Pro Cal system with its more accurate mic and more powerful software to redo the calibration. Once finished, It shows what I take to be fairly accurate "before" graphs. I cannot vouch for the accuracy of the "after" graphs but I must say it sounds really good. I posted on this here.

From this point, when I can free up some time, I'd like to do more measuring. Perhaps I'll experiment with some room treatments, but these have very low WAF.

BTW, I briefly tried OmniMic, which I posted about here, but I'd been very busy with work and didn't have time to play with it to be sure it was worth it. Before the 45d return period expired I returned it. It's kinda sad when even such a simple system seems to have a pretty steep learning curve. I'm gettin old...

I tried installing both the Pro v2.2 and the Standard v2.2 on my Windows 7 laptop. The original v2 works fine and I'm able to get RTA levels with just my room tone (somewhere in the neighborhood of 50 db across all frequencies). With the new versions I can't get any levels above 10 db, except for at around 4k where it reads around 40 or 50. I'm gonna put in an email to XTZ but thought I'd see if anyone else has done this install.

Have you checked the level settings of the Recording and Playback devices in Windows 7?
I mainly use one laptop with XP which works fine with both new and old.
My newer ASUS with Windows 7 64-bit which I don't use so much yet
works fine with one quirk, there is a high pitched sound, like a sound loop,
when I do to the "Room Analyzer" and "Full Range" sweeps but not during the RTA measurement or the Tone Generator sound. I haven't dug any
deeper into that yet.
I had some trouble with a 4K lift earlier, see previous posts, but I haven't
noticed that with the II Pro version (yet).

I posted in the Omnimic thread, but I feel this is relevant. Is 1/6 octave resolution really good enough to measure frequency response? I'm thinking of getting the Pro II kit, but I'm worried that the measurements will be too coarse to be of any value.

I need a measurement kit that offers accurate results for acoustical analysis and basic calibration (measuring response, setting speaker/subwoofer levels etc). Does Omnimic offer higher resolution measurements, or are they both similar?

Hi XTZ pro 2 is now 1/12 th resolution in the bass, plus still has the great bass decay graph and EQ functionality including parametric EQ software emulation as in the original!

Hi Nyal,

I've asked this question before but is 1/12 octave resolution sufficient for acoustical analysis? I'm concerned the response will be too coarse with such low resolution. I want to see the unsmoothed result, showing the warts and all.

I'm confused why programs like REW offer much higher resolution (and it's free). I'm considering this (and Omnimike), for simplicity and convenience over REW, I'm just not sure if it offers the accuracy needed to properly measure rooms. I could be wrong on all of this. I've heard on other forums that anything less than 1/24 octave resolution would be too coarse. Perhaps this can be updated in a new software release or something? What are your thoughts on this?

IMO, it mainly depends on your goals. Are you just wanting a fine-resolution reading for your own information and edification, or are you trying to equalize?

If the latter, sure - you’ll get the best results with higher resolution. But up until about 6-7 years ago, people commonly used 1/6-octave test sine wave test tones to manually create graphs and used them to set parametric equalizer filters. Just about universally, people were pleased to report a significant and audible improvement. Generally, you can get an audible improvement with subwoofer equalization by merely eliminating the worst peaks and troughs. Most people are happy with this approach.

However, if you’d prefer to equalize for the best waterfall graph (i.e., maximum improvement in decay times), then you’ll want the full 1/24-octave resolution. I’m personally unconvinced that this delivers an audible improvement over more casual equalization that merely eliminates the peaks and troughs, but many feel that is the best way to equalize a subwoofer.

So – it all gets down to what your goals and expectations are.

Regards,
Wayne A. Pflughaupt

Hi Wayne! Long time no see. Yes, I simply require acoustical analysis of my room and I do not need to apply EQ filters. I just want to know that what I'm "seeing" is an accurate reflection of what exists in my room, hence the question concerning the 1/12 octave resolution.

Would you reckon for straight analysis it's more than sufficient? I'm quite content to add EQ (auto EQ) and see a before and after, rather than manually applying EQ filters. Some people tell me that 1/6 octave would be fine, others argue that 1/48 would be sufficient, so it's a little confusing.

Nyal, what is your stance on the whole high resolution argument? Is 1/12 octave good enough in the lower bass for simply measuring and seeing the before and after etc?

Yes, I believe so.

The 1/24th does show better the shape of the peaks and dips as expected but sometimes you can lose the ability to see patterns with higher resolution measurements.

I believe you have to look at low frequencies at multiple different resolutions for this reason. Most typically I will use 1/3rd and 1/12th.

Note that 1/3rd octave is roughly equivalent to how we 'sum' nearby frequencies when we perceive how 'loud' they are but we can perceive individual 'timbral' distortions down to maybe 1/6th or at most 1/12th octave.

Another way to consider it is to think about the smallest frequency pattern you are trying to resolve and whether the degree of smoothing applied will allow you to see it.

For example if you have the 32Hz to 64Hz octave then 1/12th smoothing is going to give you around 2.7Hz of resolution (32/12). I say around because it is a moving average filter and the size of an octave changes (16Hz to 32Hz is 16Hz but 32Hz to 64Hz is 32Hz).

If you consider that in general a room mode will at minimum take up 5Hz then you can begin to understand the effect smoothing will have on the measurement and the analysis of room modes.

Thanks Nyal for the detailed reply. If higher than 1/12 resolution was required could it not be added in as a software update? Also, does XTZ have a waterfall chart that can be displayed similarly to REW or Omnimic like so :

Haven't you even gone to the XTZ website to look at what it does or found a review on the web? Here is one of the standard screens from XTZ Pro II showing FR in the main window and the decay spectrogram (equivalent information to a waterfall). A click swaps the large and small windows.

Really? I down loaded the Pro software and get a hardware detection error with the old XTZ version mic and the new II Pro software.

The original software works fine. Any ideas?

Yes XTZ added 1/12th as a software update so no reason why 1/24th couldn't be added too.

XTZ displays the information in a spectrogram format rather than a waterfall. Same data, different presentation.