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Greetings,

I'm planning a family room/multipurpose room setup with 5.1 (1 or 2 subs) and a projector. I'd like to use REW to help with speaker positioning (sub + mains) and potential use of a few room treatments.

A very preliminary discussion on room geometry and related issues was started here: http://www.hometheatershack.com/forums/home-audio-acoustics/50833-seeking-advice-best-audio-compromise-multipurpose-room.html if things like room shape matter to this discussion (I assume they do not, but...).

Computer is a laptop running win 7, 64 bit with only a speaker out and microphone in for sound connections. USB and 1394 connections are available.

I have a camera tripod but no microphone holding equipment at all.

From searching through the forum, here is my understanding of what I'll need hardware wise (using it properly is a "whole-nother" topic).

1) Calibrated mic 15-20kHz or better, 0 and 90 degree cal files (at a minimum), sensitivity calibration as I do not have an SPL meter (or buy a separate SPL meter).
2) External USB soundcard with phantom power.
3) Either a separate mic stand or a converter bushing for my camera tripod + a microphone holder to screw onto the tripod.

Did I miss anything?

While I do not have a specific budget, I do not want to spend anymore than I have to. At the same time, I want this to "just work". I do not have a ton of free time, so time spent fiddling with "cheap" gear (i.e. problem prone because it's cheap) is not generally worth it to me.

In terms of specific hardware for each category, it looks like either of the mics sold by Cross Spectrum (Behringer ECM8000 or Dayton Audio EMM-6) with the Premium Plus calibration will do just fine.

There seems to be less data on which external soundcard is appropriate for my uses. I'm not interested in using it for anything but REW.

The TASCAM US122MKII USB Audio/Midi Interface is ~$110 and seems like it'd work, but it's not reviewed well at Amazon at least. The Alesis iO|2 "Express" version (link:http://www.alesis.com/io2express) seems like it'd fit the bill and is $90 at Amazon? I'm not positive it has all of the necessary connections though (use 1/4" monitor out as line out??).

Other suggestions that are not loaded with features I do not need?

Lastly: the mic stand. It looks like a bushing like this one http://www.bhphotovideo.com/c/product/535392-REG/General_Brand_Microphone_Reducer_Bushing.html would work so I could attach a microphone holder to my camera tripod.

Is there a disadvantage is using a converted camera tripod?

Any feedback on items I may have missed or appropriate hardware choices for my situation (and why they are the appropriate choice) is appreciated.

Thanks!
 

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I'm no expert, but is there a reason why you're looking at relatively expensive Midi interface devices, rather than the simpler Behringer XENYX502 5-Channel Mixer plus any USB sound card with a line in, which together should come out under $75 or less and are pretty well guaranteed to work since that what so many others use?

The only disadvantage I can see to using a tripod instead of a mic boom is a tripod only works directly above it. If you wanted to position the mic over your normal seating position, that means putting the tripod on the cushion of your chair/sofa, or moving the chair/sofa out of the way. The arm on a mic boom means you can keep the stand solidly on the ground and move the mic over to just where you need it without moving any furniture.
 

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Great thread with good timing. I am in the same place as the OP and am looking for these answers as well. I am beginning a twin build of 4cf cabs with 15" drivers for placement in my family room. I'd like to utilize REW to help set up the room, but like the OP, don't have a large budget to spend on a bunch of equipment or the inclination to fuss with the set-up once I get 'in the zone'.

Brad
 

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1) Calibrated mic 15-20kHz or better, 0 and 90 degree cal files (at a minimum), sensitivity calibration as I do not have an SPL meter (or buy a separate SPL meter).
Ninety-degree readings are bogus IMO - see here - but a lot of people seem to think they’re useful. However, the additional cost for both 0º and 90º calibration is minimal, so no reason not to get both.

There seems to be less data on which external soundcard is appropriate for my uses. I'm not interested in using it for anything but REW.
The main issue with sound cards is whether or not they “play nice” with your operating system. It’s always a good idea to Google for some reviews of any sound card you’re considering. This post explains what to look for in a review.

Kalani makes a good point about the higher-priced soundcards. Behringer has a new item, the 302USB you might look into - see this thread. Unfortunately, no one here has tried it yet, so if you want to play it safe you might just stick with the TASCAM 122.

Regards,
Wayne
 

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For what it's worth, I intend to pick up a Griffin iMic for the "sound card" duties, to go along with my Xenyx 502. Roughly $25-30. Small, no drivers needed on XP/Vista/Win7/OSX, has the requisite Line in, and Griffin has a good rep among Mac users.

If I knew more about the 302USB, I'd probably give that a shot and save about $10 in an all-in-one solution, but I'd rather stick with the tried and true for now.
 

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Thanks for the replies!

Wayne, I read those links, very informative.

Kalani, while I have a natural preference for 1 device to rule them all, I would be OK with 2 as well. I'm not sure when you are pulling the trigger on the setup you describe, but I'd appreciate feedback on your results.

Thanks again!
 

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Just a few comments.

Various mics do indeed have an optimal orientation with regard to the target where their phase linearity and frequency response is optimized. This orientation is normally specified by the manufacturer. And 90 degrees perpendicular is indeed a common optimal orientation. An example of this is the Earthworks M30.

That said, what the optimal orientation of the Behringer mic is, who knows.

Additionally, if one is acquiring a frequency response, it really doesn't matter what angle the mic is oriented! The problem is not really one so much of mic orientation (which in this scenario is a smaller issue), but rather one of the fundamental limitations of the frequency response.

The reason is that at any orientation you are going to get some mix of direct and indirect signals. In other words, the measured response will be non-minimum phase and as such NO frequency response will be accurate. It will necessarily suffer from the destructive effects of the superposition of the varying direct and indirect signals and what you observe will not represent an accurate frequency response of the direct signal due in large measure (but not exclusively) to the effects of comb filtering!

Nor will calibration files that include various orientation be of much use, as this will not correct for the effects of non-minimum phase interference. As there is NO way for such a calibration file to anticipate the dimensions of the room, the Q of the source, or the mix, gain, and arrival times of various direct and indirect signals that will necessarily vary in each unique space and mic position.



Hence why such environments are optimally analyzed in the time domain with measurements such as the ETC response, that display the precise nature of all of the varied energy arrivals in terms of arrival time, gain, and 'quality' of the various signals (diffuse, specular, etc...), and also allow one to determine their angle of orientation as well as the points of boundary incidence.


Thus, if one cannot even obtain a valid baseline direct signal frequency response, let alone determine what regions are minimum phase (if any), one can only imagine what the results of EQ will be - considering that EQ is Not effective for non-minimum -phase environments. Thus, one should temper their expectations of an 'automatic system for the generation of EQ' to be very accurate. But it Will be "different".:D
 

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Thanks for the replies!

Wayne, I read those links, very informative.

Kalani, while I have a natural preference for 1 device to rule them all, I would be OK with 2 as well. I'm not sure when you are pulling the trigger on the setup you describe, but I'd appreciate feedback on your results.

Thanks again!
I'm right there with you, I just happen to think that the two-part solution will more likely prove useful in other areas as well... I've always wanted a small mixer, so this is a good excuse. The Tascam or Alesis might work for that, but they cost noticeably more, and havn't been specifically reviewed here before, that I see.

The one thing that gives me pause is the 302USB... The 302USB essentially combines the two parts I bought into one unit, at a price similar to, or slightly below, the two-piece solution. I would go that way in a heartbeat if I had any sort of confirmation that it will work, but I don't really want to a guinea pig here... there's enough for me to learn here as it is without having to be a trailblazer as well. If I have questions, I want to be able to ask people questions about the the exact same piece of gear, and the Xenyx 502 is probably the single most commonly-used mixer/preamp I see mentioned.

I've already ordered the mic and the 502, and I'll be ordering the Griffin iMic any day now (although that's likely the least important part... I'm not even 100% certain I need it, but haven't had a chance to really look into my existing hardware yet).

I'll be posting results of my gear combo, have no doubt. :)
 

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I would go that way in a heartbeat if I had any sort of confirmation that it will work, but I don't really want to a guinea pig here... there's enough for me to learn here as it is without having to be a trailblazer as well.
Why not see if you can pick up a 302 at your local Guitar Center? I think they have a generous return policy - you could just take it back if it doesn't work! :T

Regards,
Wayne

 

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Why not see if you can pick up a 302 at your local Guitar Center? I think they have a generous return policy - you could just take it back if it doesn't work! :T
Frankly, if I had seen the posts discussing the 302USB before I placed the order for my 502, I might have given it a shot. At this point, though, someone else is going to have to be the guinea pig.
 
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