USNRET Posted May 16, 2017 Author Share Posted May 16, 2017 1 hour ago, Chris A said: How can I help? What do you want to do? I probably won't have a chance to do anything until this weekend. If you are free to talk at some point perhaps a phone call to lead me thru setup in preferences and then .... reading this now plus the other searches https://www.minidsp.com/applications/acoustic-measurements/umik-1-setup-with-rew Ok since I am measuring room here not electronics I guess my first question (other than how to run REW) is to what system to use. - the easiest connection would be to the MX151 via HDMI since the C2500 does not have HDMI input but does have USB and analog. - should I be testing with "Room Perfect" bypassed and in pure stereo mode? - should I test with or without subs? Right now I have the two channel set up with no subs and the pre-pro set in stereo with crossovers set as below and this was just some random numbers I choose. The KHorns have enclosed backs. - If I use the pre-pro I am guessing that I need to go back and set the the L/R as full range with no subs and natural roll off just to see what the L/R do alone in the room Quote Link to comment Share on other sites More sharing options...
USNRET Posted May 16, 2017 Author Share Posted May 16, 2017 or I could go USB from laptop to C2500 preamp direct to amp. There is another option to go headphone out from laptop to analog in to preamp. Either of this would negate the hassle of going thru the setup on the MX151. I could put the Room Correction wired between preamp and amp in bypass or connect pre and amp direct without the MEN220. Quote Link to comment Share on other sites More sharing options...
Chris A Posted May 16, 2017 Share Posted May 16, 2017 2 hours ago, USNRET said: should I be testing with "Room Perfect" bypassed and in pure stereo mode? If you're bypassing your EQ, then that's probably not what you're trying to achieve. The reason for using REW is to see what you're starting with, and also see the effects of the changes that you make to your EQ and delay adjustment as you correct the delays and EQ. 2 hours ago, USNRET said: should I test with or without subs? That depends. Generally, if your subs are configured like another "way" of each loudspeaker (like mine are arranged--with the TH subs directly behind my fronts and crossed over like they are part of the fronts), then you can measure them together with the fronts/center. It appears that is the way that you've got yours set up. You can measure the subs separately later from the fronts and center. 2 hours ago, USNRET said: If I use the pre-pro I am guessing that I need to go back and set the the L/R as full range with no subs and natural roll off just to see what the L/R do alone in the room I recommend getting and saving measurements both ways--but remember that you're measuring one loudspeaker at a time. However you decide to connect the upsweep from REW on your laptop into your preamp--it should allow you the freedom of making changes to delays and channel EQs between sweeps to see when you've got everything corrected properly. If your REW upsweep output connection bypasses your room correction device or firmware/software, then you're not really achieving what you want. Since I personally use a AVP and active crossover (with the active crossover doing everything but channel delay and channel gains--which the AVP handles), so I use HDMI out of the laptop to drive one of the HDMI inputs to the AVP. This eliminates the added headache of having to calibrate your analog soundcard output. Chris Quote Link to comment Share on other sites More sharing options...
USNRET Posted May 16, 2017 Author Share Posted May 16, 2017 So I start with HDMI to prepro as it is configured in stereo 5.2 with room perfect engaged, voicing neutral and no post processing and see what I get. That part makes it easy to set via PC interface. Perhaps tomorrow evening we can go thru REW preference menu to set input / outputs and options. 1 Quote Link to comment Share on other sites More sharing options...
USNRET Posted May 17, 2017 Author Share Posted May 17, 2017 so my 'new' 8.1 Windows laptop had issues (or I did) so I reverted to my daughter's WIN 7 and got sound in 2 channel after 3 hours of cleaning it. This may mean nothing but it seems to me that I have eh, problems in the <200 Hz area but then again I am flying in the blind but trying to get something working. This is L/R with room Perfect on and off. Mic at center pointing up approx 8' right triangle to speakers Quote Link to comment Share on other sites More sharing options...
USNRET Posted May 17, 2017 Author Share Posted May 17, 2017 EQ on and off Quote Link to comment Share on other sites More sharing options...
USNRET Posted May 17, 2017 Author Share Posted May 17, 2017 LH EQ On Quote Link to comment Share on other sites More sharing options...
USNRET Posted May 17, 2017 Author Share Posted May 17, 2017 RH EQ On Quote Link to comment Share on other sites More sharing options...
Chris A Posted May 17, 2017 Share Posted May 17, 2017 Looks reasonably flat above 200 Hz. If you switch to the Impulse view using the 4th button in the button bar just above the plot area, you should see something like this (in this case, the "controls" menu button has been pushed to show the options for this particular view: If you placed your microphone at the listening position when you ran the sweeps, and repeated your measurements for each loudspeaker in your setup, one at a time, then you would be able to see the time delay associated with each channel quite accurately by reading the relative time delays. If you select the "Overlays" button from the top menu bar, then select "Impulse" from top menu bar, you will see all of your opened measurements impulse responses overlaid on each other for much easier comparison of delays for each channel: From this point, you can adjust the channel delays for each channel to adjust to match impulse response peaks in order to achieve time alignment of your surrounding channels. Chris Quote Link to comment Share on other sites More sharing options...
Chris A Posted May 17, 2017 Share Posted May 17, 2017 7 hours ago, USNRET said: ...This is L/R with room Perfect on and off. Mic at center pointing up approx 8' right triangle to speakers If you select the "Graph" menu from the main plot area in your original plots above, you will see the many options to smooth each measurement. I recommend selecting "Apply Psychoacoustic", then all the hash that you see on the plots will be smoothed out and the result will be something that corresponds much more closely with how your ears actually hear the frequency response of your loudspeakers. Quote Link to comment Share on other sites More sharing options...
USNRET Posted May 17, 2017 Author Share Posted May 17, 2017 13 hours ago, Chris A said: If you switch to the Impulse view using the 4th button in the button bar just above the plot area, you should see something like this ^^Never figured this one out.^^ Where do I start from? Water fall? All SPL? Psychoacoustic applied? Anyway, here is the two channel, no sub with Psychoacoustic applied. Magenta is Room Perfect ON and Green is Room Perfect Off. Still using MX151 prepro This is from my first and only runs and the mic was sitting on the coffee table in front of the candy bowl / dish / wife things in the room photo above.Subs and mains set at 50 Hz cut / natural roll off. Forgot no subs. Just from this alone I would like to mock up false walls and see what happens. And to be honest here, the 'treatments' on the front wall have no quantitative reason for being there so removing them for a run would be fun (when I have a day to two alone in the house; yea, sure....) I need to figure out my laptop sound options so I can utilize all 5.1 channels but I am making a little progress thanks @Chris A Quote Link to comment Share on other sites More sharing options...
Chris A Posted May 17, 2017 Share Posted May 17, 2017 Right here in the yellow lasso area: Quote Link to comment Share on other sites More sharing options...
USNRET Posted May 17, 2017 Author Share Posted May 17, 2017 ^^ Did that and got a mess on the screen, I'll get it for you. Quote Link to comment Share on other sites More sharing options...
USNRET Posted May 17, 2017 Author Share Posted May 17, 2017 Obvious I am not doing something right Quote Link to comment Share on other sites More sharing options...
Chris A Posted May 18, 2017 Share Posted May 18, 2017 If you scroll to the right until it counts down to "0m" (i.e., zero milliseconds) then perhaps you'll see the impulse response that's somewhat reminiscent of the impulse plot I posted above. At that point, then if you open your earlier measurements for the other loudspeakers in your array (or run new ones) with the microphone in the main listening position, then open the "Overlays" button, then select "Impulse" you should be able to see the relative impulse peaks and read the misalignments relative to each other in milliseconds or fractions of milliseconds, then you can correct the delays that you mentioned at the start of this thread. If you are wanting to flatten the response of your loudspeakers, we can move on to that subject...? Quote Link to comment Share on other sites More sharing options...
USNRET Posted May 18, 2017 Author Share Posted May 18, 2017 2 minutes ago, Chris A said: If you are wanting to flatten the response of your loudspeakers, we can move on to that subject...? Well YEA, since that is the point but until I learn some basic buttonology here in order to replicate the tests not much sense. I do need to get some quite time, set up the mic at listening position and get an accurate sweep. Quote Link to comment Share on other sites More sharing options...
Chris A Posted May 18, 2017 Share Posted May 18, 2017 Okay, I certainly understand that. I'll go any direction that you want to go. Let me know when you're ready... 1 Quote Link to comment Share on other sites More sharing options...
USNRET Posted May 19, 2017 Author Share Posted May 19, 2017 @Chris A Played around today. At listening positioning / height. Mic pointed up with 90* cal file Ended up with Room Perfect engaged and both subs on (split monos) 63 Hz on subs / full range on Khorns Looks like the subs aren't doing much. Must be my prepro set up, still learning the processing menu. Edit: I just noticed that somewhere in my settings I lost the subs in stereo mode. Quote Link to comment Share on other sites More sharing options...
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