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Discussion Starter #1
Hello. Trying to set up the EQ Wizard and wanted to ask a question. I have a Roland Quad Capture for my interface and it has line outs, but the ins are combo XLR/TRS inputs. Will it work if I loop the sound this way? Just wanted to make sure I get this right...Thank you for any suggestions you may have.:dontknow:
 

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<<<<SNIP>>>
Will it work if I loop the sound this way? Just wanted to make sure I get this right...
Yes, it'll work ( as long as you run Windows & not OSX ) !

- You won't blow up anything as long as the 48V phantom is turned-off ( in case you happened to use the XLR connector instead of the TRS at the input ) .

:sn:
 

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Discussion Starter #3
Thanks for the answer...still concerned a bit, the Quad Capture has combo inputs that have phantom power. I bought a condenser mic to test with, and need the power for the mic, but if I use the other in to loop through, this one will have phantom power as well, so now what...I do really love THIS soundcard/interface. I really don't want to have to buy another one just to test my room...kinda defeats the purpose of it all...any ideas?
 

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- The 48V is applied ( typically ) to only the XLR portion of those combo jack / meaning you shouldn't be worrying so much about this .
- But ( to alay your fears ) ;

This voltage is measurable ( when applied to a mic cable ) .

(i) Simply plug a TRS cable into the input of your soundcard . Turn on the phantom 48V switch .
- Using a DVM set to DC volts, measure the other end of the TRS cable ( between sleeve & tip , or sleeve & ring ).
- You shouldn't see 48volts .

(ii) OTOH, if you do this exercise with a mic cable plugged into the XLR portion ( with the 48V phantom applied ) , you should be able to measure 45-48 volts between pins 1 & 2 ( or pins 1 & 3 ) .


:sn:
 

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Discussion Starter #5
Thanks for all the info. I wasn't sure and didn't want to blow up anything LOL. Thanks again for all your help!:wave:
 

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Discussion Starter #6
I have just one more question...I only have two outs on this interface. How do I loop it back through AND hook up both of my speakers? I am thinking that I need to get another sound card and I want to avoid that if possible. Any suggestions?
 

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I have just one more question...I only have two outs on this interface. How do I loop it back through AND hook up both of my speakers? I am thinking that I need to get another sound card and I want to avoid that if possible. Any suggestions?
- You don't need a second sound card .

- Keep in mind that it's generally recommended that you measure one speaker at a time ( including the sub, then combinations of them all, to see the resulting responses ) .

- Anyways, to keep your loopback cable in place ( useful for timing purposes, I suppose ) you'll need to split the signal leaving your one remaining output ( going to the AVR ) .

- Effectively, you'l' end up sending the same mono signal into both of the receiver's inputs ( via a cable splitter ) .

- Cable/signal splitters ( "Y" cables ) are available from a few places .

:sn:

BUY something like one of these ( to accomplish the signal split ) ;

or ;

- then you'll need a set of these ( to get the split signal into your AVR ) ;



- Under no circumstances buy a pair of these "insert type" cables thinking that they do the same thing as a true split // they aren't the same !
- ( If you were to use them with both main speakers playing back the mono test signal, you'd have some very large and strange cancellations due to the signals being opposite in polarity/phase ) ;

 

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Discussion Starter #9
I am still having issues. I watched this video tutorial on YouTube-- http://youtu.be/e4uSR3cUUSY-- and the guy adjusts his levels during the calibration (it looks like he is doing it with the mouse icon actually) to match the -12db and then saves the results, then uses those calibration results to test his room. I cannot for the life of me understand how to set the levels and do the calibration. I have gotten so frustrated that I even tried my on board Realtek sound card because I thought the phantom power was interfering or something, just could not get that calibration done. So, now, after testing the other sound card, I have come to a conclusion. I have no idea what I am doing. :blink:

I do not have an AVR either, I am running directly into the interface. Since I bought the Quad Capture, I have even been able to eliminate having a mixer and a preamp. This is a studio, by the way, not sure what everyone has here...I think some are only trying to optimize their audio/video in their homes.

I have read the help files on here and I'm still a little befuddled. Please explain or show me how...and make it dummy-proof. I'd really appreciate it.:sad:
 

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Discussion Starter #11
I really do appreciate all the help from you. I have since calibrated the sound card and I think I have my first readings, but am a bit puzzled...I did use the Quad Capture by the way and the Behringer mic to test that is recommended (ECM8000) and I have some pics of the responses I am getting. I just want to make sure I am doing this right because the mic responses look pretty flat to me. I do have monitoring off, so that's not it. test.jpg

test waterfall.jpg

I don't know if this how you insert pics. I did it as attachments..is that right?:huh:
 

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That measurement is of a loopback connection somewhere, either an external wired connection or an internal hardware or software monitoring path.
 

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Discussion Starter #13
Ok. Thank you...I'll keep trying. Maybe go back to the other sound card...I know it doesn't have monitoring.
 

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Discussion Starter #14
made some more adjustments. It still looks like a loopback or monitoring prob to me??? I am starting to at least get a curve. I finally got the levels on the soundcard to -12db, and turned on/off ASIO monitoring, not sure exactly what to do there...here's more shots.

1.jpg

2.jpg

I don't know if this is any better.:doh:
 

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That is still a loopback/monitor path of some sort (way, way too clean for a room measurement). It rises at the low end because the inverse C weighting correction is turned on in REW (that is why there is a C-1 next to the value in the legend), you only need that if you are using an SPL meter as your input, it can be turned off by selecting "mic or Z weighted SPL meter" as the input type on the REW Mic/meter preferences tab. Do you have a loopback connection on the channel you are not using for measurement? Have you told REW to listen on the correct channel?
 

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Discussion Starter #16
Yeah, went through your help files again and I think I found the problem. Thank you for all your help thus far...trying again...:dumbcrazy:
 

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No, that's not better .

I'd suggest that you try your other soundcard .

The workings of this Roland card has ( obviously ) gotten you a bit flummoxed.


:sn:
 

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I have Roland Octa-Capture, and have no difficulties on Windows XP machine. What OS are you using?

Front panel mix knob must be fully "playback".

Operating system mixer must have inputs muted in output mix.

Soundcard monitor mixer must have inputs turned all the way down.


input mixer.gif

Frequency response display zoom in on amplitude is simpler, clearer view of results for purposes here.

For loopback performance checking start with input sensitivity all the way down.

To see full performance use sweep 2Hz-24kHz 256k or 512k length for sample rate 48kHz.

For trained eyes, close inspection of impulse response can be very telling.

If you run a loopback as described and save measurement results as REW .mdat file and attach to post I will take a look at what you've got.

Regards,

Andrew
 

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I have Roland Octa-Capture, and have no difficulties on Windows XP machine. What OS are you using?

(i) Front panel mix knob must be fully "playback".

(ii) Operating system mixer must have inputs muted in output mix.

(iii) Soundcard monitor mixer must have inputs turned all the way down.




Frequency response display zoom in on amplitude is simpler, clearer view of results for purposes here.

For loopback performance checking start with input sensitivity all the way down.

To see full performance use sweep 2Hz-24kHz 256k or 512k length for sample rate 48kHz.

For trained eyes, close inspection of impulse response can be very telling.

If you run a loopback as described and save measurement results as REW .mdat file and attach to post I will take a look at what you've got.

Regards,

Andrew
Thanks ! Andrew for weighing in here . :T

With all the info that you've provided, hopefully our ( young ? ) friend will finally get a handle on properly managing his signal flow .

:sn:
 
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