newbie needs help getting started

[shawn]

Please be kind, first post here lol.
My neverending quest to improve my sound in the theater has lead me here. I have never, ever, done any type of measurements before and I'm quite new to this.

I currently have the x-meridian soundcard in my vista pc using analog outputs to my denon 5800 receiver ext-in. Well that was until today. Now I have the front channel output of the xm going to a 31 band dual eq and then to the denon.

For the measurements I plugged my mackie soundbaord into the 'line-in' of the xm card and have a microphone plugged into channel 1 on the board. (tried plugging mic with adaptor straight into the card but it didn't work.

I have set my vista audio panel to 'x-meridian speakers' output and the 'x-meridian line-in' for the input.

I downloaded the new java and installed the roomeq wizard software. Read the directions, and got stuck. Step 1 was calibrating the system and that's where I am stuck already. I ran a cable from the 'front channel 1/8" jack' output of the xm card to the line-in input and tried to check levels. It didn't work so obviously either I'm an idiot or I'm missing something here.

My goal was to try and measure the front channel speakers make a graph and use that to adjust the eq. then do the same for the rear speakers, and finally the side speakers. I will add 2 more eq's if I notice a decent difference trying the first one on the front speakers. At the moment I am not worried about the sub as I could not find an eq in the store that focused on the 'sub' range.

Could someone please give me step by step directions that a 4 year old could understand? I'd really appreciate it.

[Otto]

shawn wrote:

I downloaded the new java and installed the roomeq wizard software. Read the directions, and got stuck. Step 1 was calibrating the system and that's where I am stuck already. I ran a cable from the 'front channel 1/8" jack' output of the xm card to the line-in input and tried to check levels. It didn't work so obviously either I'm an idiot or I'm missing something here.

Hi Shawn, and welcome!

It sounds like you are on the right track. Using the loop back cable provides the means to create a soundcard calibration file. Sounds like that's where you got stuck.

First, is there any sound coming out of the speakers when you are connected the way you are? I.e., if you use the "Generator" feature of REW, you should hear something coming out of your speakers. I would probably select pink noise, and start with your receiver's volume at minimum. If you get nothing at this point, there's something wrong with the output from your PC, or the input to your receiver, or, I suppose, the cable.

Second, are you getting sound back into your PC (i.e, is REW "hearing" anything)? You should be able to use the "Levels" feature of REW to show the output and input levels as seen by REW. You should be able to see the meter move if you talk into the mic or clap your hands, etc. If you are getting nothing into REW, it could be the soundcard, cable, setup, mic or mixer. We can check into those things.

Finally, is it possible that either the input and/or output of the soundcard is muted? Check in "Control Panel" for "Sounds, Speech and Audio Devices" or use the little speaker icon in your "task tray".

If that's all working, let us know, and we can keep looking into it.

My goal was to try and measure the front channel speakers make a graph and use that to adjust the eq. then do the same for the rear speakers, and finally the side speakers. I will add 2 more eq's if I notice a decent difference trying the first one on the front speakers. At the moment I am not worried about the sub as I could not find an eq in the store that focused on the 'sub' range.

Well, if you made it this far, you probably know that most REW/BFD usage is targeted at subs for a few reasons. Many of us are trying to address room nodes that are not part of the sub's intended or anechocally measured frequency response. It's a good and cheap way to fix room nodes, which are excited by the large volume of air moved by the subs. For main speakers, it's easier to handle their reflections by room treatments. Also, the ability to measure in the higher registers is limited in the tools we have. You'll see that as frequencies get higher, the measured response gets really ragged. REW will have a heck of a time predicting all those peaks, and will definitely be limited by the fact that the BFE has only 12 filters to use. You have 31, which is quite a few more, but are they parametric? Will you be able to adjust gain, bandwidth and frequency, or are your frequencies and bandwidths fixed? Anyway, all that said, please don't think I'm trying to shoot you down. By all means, go for it! Measure and post your graphs before and after. I don't see this come up much, so perhaps you can get a positive and interesting result.

So, I hope that helps, and let us know how it goes, especially if you're still having problems.

[shawn]

Otto wrote:

Hi Shawn, and welcome!

It sounds like you are on the right track. Using the loop back cable provides the means to create a soundcard calibration file. Sounds like that's where you got stuck.

First, is there any sound coming out of the speakers when you are connected the way you are? I.e., if you use the "Generator" feature of REW, you should hear something coming out of your speakers. I would probably select pink noise, and start with your receiver's volume at minimum. If you get nothing at this point, there's something wrong with the output from your PC, or the input to your receiver, or, I suppose, the cable.

Second, are you getting sound back into your PC (i.e, is REW "hearing" anything)? You should be able to use the "Levels" feature of REW to show the output and input levels as seen by REW. You should be able to see the meter move if you talk into the mic or clap your hands, etc. If you are getting nothing into REW, it could be the soundcard, cable, setup, mic or mixer. We can check into those things.

Finally, is it possible that either the input and/or output of the soundcard is muted? Check in "Control Panel" for "Sounds, Speech and Audio Devices" or use the little speaker icon in your "task tray".

If that's all working, let us know, and we can keep looking into it.

Ok, obviously unplugging the 'loopback cable' and plugging front speakers back into my system, I run the generator and do indeed get sound from my front speakers. That part seems to work ok.

I get stuck on the 'input' section.
I have my x-meridian line-in selected in cpanel and when I talk into the mic I see the meter move in vista. However I do not see it move in roomeq. Didn't see a 'levels' feature, but did turn on the vu meters and they do not move when talking into the mic, though the meter does move in vista cpanel.

ideas?

[shawn]

Just so my setup is clear in trying to get roomeq to 'hear' me.
I have the mackie soundboard line out cable going to the 'line in' cable on my xm card. There is a microphone plugged into line1 on the mackie board and levels are set so that when i talk into the mic the meters move to 'normal' ranges.
In the 'sound' tab in vista the xm 'line-in' is checked as default.
When I talk into the mic via the soundboard I can indeed see the meters move in vista 'sound' tab.

Inside the 'settings' of roomeq I have tried the 'default' input sound, and also tried choosing the x-meridian line-in as well but nothing shows on teh vu input meter for roomeq no matter what setting.

I'm guessing that my input is not muted as vista sees it fine. It's just roomeq that wont see it at this point. That's where I am stuck at the moment.

[Otto]

shawn wrote:

Ok, obviously unplugging the 'loopback cable' and plugging front speakers back into my system, I run the generator and do indeed get sound from my front speakers. That part seems to work ok.

I get stuck on the 'input' section.
I have my x-meridian line-in selected in cpanel and when I talk into the mic I see the meter move in vista. However I do not see it move in roomeq. Didn't see a 'levels' feature, but did turn on the vu meters and they do not move when talking into the mic, though the meter does move in vista cpanel.

ideas?

OK. Seems like most things are set up correctly. You were right, BTW, it's not "levels" as I said, but "VU Meters" that will show you if anything's coming in from REW's point of view.
Now, by "cpanel" do you mean Windows' Control Panel? That's OK. In REW, there's a "Settings" button. Hit that and you'll see a "Soundcard" tab. You've probably already been here. At the top are selections for "Output Device and Output" and "Input Device and Input". Below that there is a box to "Control input mixer/volume" and a value for "Input Volume". What's set up for the all the input stuff?

I'm not familar with your particular sound card, so you might have to fiddle with some of those options. In that second drop-down menu, you might have selections like "default input" and "line in" Play around with those to see if anything makes a difference. Check the "Control input mixer/volume" and set the input volume to 1.00.

If all that stuff is OK, and it may already be, we'll have to look for something else.

Is it possible that you are accidentally using the mic in rather than the line in?

Edit: I just read the previous post, after posting my response.

Not sure where else to go. I'll think about it. brucek may also have an answer.

[shawn]

Otto wrote:

OK. Seems like most things are set up correctly. You were right, BTW, it's not "levels" as I said, but "VU Meters" that will show you if anything's coming in from REW's point of view.
Now, by "cpanel" do you mean Windows' Control Panel? That's OK. In REW, there's a "Settings" button. Hit that and you'll see a "Soundcard" tab. You've probably already been here. At the top are selections for "Output Device and Output" and "Input Device and Input". Below that there is a box to "Control input mixer/volume" and a value for "Input Volume". What's set up for the all the input stuff?
.

the 'control input mixer/volume' and 'input volume' are greyed out. I can't select them no matter what input source I choose above. 'control output mixer/volume' is not greyed out though that is not what we're trying here.

in the input selection 2nd choice I choose line-in/master volume turns it so it's not greyed out, but I cannot put any value in there, it reverts back to 0.000 no matter what.

by cpanel I mean the vista control panel, click on sound, and it shows me my input selections. Vista does not have a 'mixer' per say like xp did for the recording side. You simply select your input, set it as default, and then click on the properties for that device to set the recording level etc.

[MakeFlat]

shawn wrote:

Just so my setup is clear in trying to get roomeq to 'hear' me.
I have the mackie soundboard line out cable going to the 'line in' cable on my xm card. There is a microphone plugged into line1 on the mackie board and levels are set so that when i talk into the mic the meters move to 'normal' ranges.
In the 'sound' tab in vista the xm 'line-in' is checked as default.
When I talk into the mic via the soundboard I can indeed see the meters move in vista 'sound' tab.

Inside the 'settings' of roomeq I have tried the 'default' input sound, and also tried choosing the x-meridian line-in as well but nothing shows on teh vu input meter for roomeq no matter what setting.

I'm guessing that my input is not muted as vista sees it fine. It's just roomeq that wont see it at this point. That's where I am stuck at the moment.

Sometimes it is hard to tell if the left line-in or the right line-in is selected. REW uses either the right (default) or the left channel for input - user can select either channel by clicking on the dot to select the channel. You may want to test the other input channel.

[shawn]

MakeFlat wrote:

Sometimes it is hard to tell if the left line-in or the right line-in is selected. REW uses either the right (default) or the left channel for input - user can select either channel by clicking on the dot to select the channel. You may want to test the other input channel.

tried that, no difference.

[MakeFlat]

shawn wrote:

tried that, no difference.

How about the volume level of the input as indicated in REW?

[MakeFlat]

shawn wrote:

the 'control input mixer/volume' and 'input volume' are greyed out. I can't select them no matter what input source I choose above.

Are you using windows XP? You will need to check the control panel, the audio tab should show the sound card you are using as selected. If not, click the drop down to select your particular sound card. (you will have to exit REW setup first or your OS will not let you change anything)

[shawn]

MakeFlat wrote:

How about the volume level of the input as indicated in REW?

http://mydreamhost.net/images/roomeq1.jpg sorry no photoshop on this computer and image to big to put into thread.

i was actually talking into the mic as well and volume levels for mic input were showing in the cpanel.

[shawn]

MakeFlat wrote:

Are you using windows XP? You will need to check the control panel, the audio tab should show the sound card you are using as selected. If not, click the drop down to select your particular sound card. (you will have to exit REW setup first or your OS will not let you change anything)

No using vista 32bit

[shawn]

http://mydreamhost.net/images/roomeq2.jpg
this picture shows that I have the right selection in vista and the green bars on right show there is an input signal shown. Just not in roomeq......

[shawn]

No idea what changed, but somehow I am now getting the mic to show up... now onto testing, hope this part is easier than the last few hrs lol.

[MakeFlat]

shawn wrote:

http://mydreamhost.net/images/roomeq1.jpg sorry no photoshop on this computer and image to big to put into thread.

i was actually talking into the mic as well and volume levels for mic input were showing in the cpanel.

If you use a mic then you will need to select MICROPHONE input in REW. If you used a mic and a pre-amp plugged into LINE IN of the PC then you would use LINE IN.

OOPS you got ahead of me. Good job.

[shawn]

Otto wrote:

Well, if you made it this far, you probably know that most REW/BFD usage is targeted at subs for a few reasons. Many of us are trying to address room nodes that are not part of the sub's intended or anechocally measured frequency response. It's a good and cheap way to fix room nodes, which are excited by the large volume of air moved by the subs. For main speakers, it's easier to handle their reflections by room treatments. Also, the ability to measure in the higher registers is limited in the tools we have. You'll see that as frequencies get higher, the measured response gets really ragged. REW will have a heck of a time predicting all those peaks, and will definitely be limited by the fact that the BFE has only 12 filters to use. You have 31, which is quite a few more, but are they parametric? Will you be able to adjust gain, bandwidth and frequency, or are your frequencies and bandwidths fixed? Anyway, all that said, please don't think I'm trying to shoot you down. By all means, go for it! Measure and post your graphs before and after. I don't see this come up much, so perhaps you can get a positive and interesting result.

Wow you weren't kidding, this proggy seems to have real issues graphing full range. It's late and the graphs make no sense at this point so I'll attack it again tomorrow.

I didn't buy the bfe because the stats for 'main speakers' really sucked bigtime. Something like 24bit 64khz, which is nowhere near what I am looking for as I'm outputting 24bit 192khz from the xm. I bought a 1/3 octive dual channel eq to test it out, heck they're cheap compared to most hifi stuff I'm used to. Only thing I hate is that it's only 90db sensativity which is nowhere near my speaker specs. If I can't tell a diff I'll end up buying 3 of them so I can eq each speaker independant.

My entire goal and point of trying this out is as follows:\
Speaker placement in my room sucks, left front speaker in corner, left right 5' from corner (door), left rear speaker sits on top of 6' of 2" 705 as a basstrap, the other rear speaker is 2' above a glass desk. And no.... I can't change placement, very small room 12x11.5x8. I have treated the front wall with 2" 705, my first reflection points with 2" 705, and my rear wall with the same.

Problem is there is no way at all without eq to get such a weird setup to 'image' correctly. Believe it or not though it does sound pretty amazing, just not quite where I want it is all. I'll deal with the bass side next.

If roomeq isn't for this and there is a better way, I'd love to hear about it. Obviously after a few hrs just trying to get started here, I'm interested in trying anything that will work.
thnx

[Otto]

shawn wrote:

No idea what changed, but somehow I am now getting the mic to show up... now onto testing, hope this part is easier than the last few hrs lol.

Wow, that's weird. I disappeared kinda early last night, so sorry I wasn't able to help better. One question -- is the "input level" value in REW now non-zero? I think that was part of the problem. Did you restart the system at some point? REW doesn't usually seem to need it, but you never know...

Anyway, glad to hear you are making progress.

[Otto]

shawn wrote:

Wow you weren't kidding, this proggy seems to have real issues graphing full range. It's late and the graphs make no sense at this point so I'll attack it again tomorrow.

I didn't buy the bfe because the stats for 'main speakers' really sucked bigtime. Something like 24bit 64khz, which is nowhere near what I am looking for as I'm outputting 24bit 192khz from the xm. I bought a 1/3 octive dual channel eq to test it out, heck they're cheap compared to most hifi stuff I'm used to. Only thing I hate is that it's only 90db sensativity which is nowhere near my speaker specs. If I can't tell a diff I'll end up buying 3 of them so I can eq each speaker independant.

My entire goal and point of trying this out is as follows:\
Speaker placement in my room sucks, left front speaker in corner, left right 5' from corner (door), left rear speaker sits on top of 6' of 2" 705 as a basstrap, the other rear speaker is 2' above a glass desk. And no.... I can't change placement, very small room 12x11.5x8. I have treated the front wall with 2" 705, my first reflection points with 2" 705, and my rear wall with the same.

Problem is there is no way at all without eq to get such a weird setup to 'image' correctly. Believe it or not though it does sound pretty amazing, just not quite where I want it is all. I'll deal with the bass side next.

If roomeq isn't for this and there is a better way, I'd love to hear about it. Obviously after a few hrs just trying to get started here, I'm interested in trying anything that will work.
thnx

Well, it sounds like you are on the right path, and that you know what you are doing. You already have quite a few treatments, so that should be helping. Small and funky rooms can be difficult to deal with.

The measurements you are getting from REW are probably somewhat accurate from the program's point of view. I think it's all the reflections in the room that might be getting in your way. What speakers are active as you measure? Are you measuring at the listening position or at some other location in the room? There might be some value to measure, say, at 1 foot or 1 meter from the speaker, as well as at the listening position. I think that as you get further from the speaker measurements are going to get more messy.

I don't know of any better ways to handle this kind of thing outside of EQ and room treatments. Good luck!

[brucek]

this proggy seems to have real issues graphing full range

Mmm, I though a proggy was something you ate..

Anyway, hopefully you don't want to measure 'full range' much past 5KHz. The Radio Shack meter is not suitable for higher frequencies and would require investing in a better microphone or meter.

You'll find that measuring above sub frequencies results in a lot of comb filtering as shown in the response below (before and after), but can be cleaned up with the REW fractional octave averaging (smoothing) feature. The smoothing will reveal large deficiencies in levels that you may be able to rectify with an equalizer. It's always a toss up that an equalizer doesn't introduce more of a negative effect from its introduction in the mains path in the form of noise or distortion compared to its positive effect of 'tone controlling'.

BTW, normally REW prefers 48KHz sampling rate unless the soundcard doesn't allow it.

UNSMOOTHED RESPONSE 25Hz to 5KHz
unsmooth.jpg

SMOOTHED RESPONSE 25Hz to 5KHz
smooth.jpg

brucek

[shawn]

Otto wrote:

Well, it sounds like you are on the right path, and that you know what you are doing. You already have quite a few treatments, so that should be helping. Small and funky rooms can be difficult to deal with.

The measurements you are getting from REW are probably somewhat accurate from the program's point of view. I think it's all the reflections in the room that might be getting in your way. What speakers are active as you measure? Are you measuring at the listening position or at some other location in the room? There might be some value to measure, say, at 1 foot or 1 meter from the speaker, as well as at the listening position. I think that as you get further from the speaker measurements are going to get more messy.

I don't know of any better ways to handle this kind of thing outside of EQ and room treatments. Good luck!

I was measuring the front left/right main speakers from the listening position with the mic pointing straight up. My intentions were to measure each speaker in the system independantly. Due to the room setup my front left speaker, being in the corner is a bit more 'boomy' than the front right speaker which is 4' from the coner due to a door. I have set the levels and delay time properly so that part is done. Now it's just a matter of trying to balance the sound. The same applies to the rear and side speakers. I have already treated the room removing first reflection points and getting rid of the flutter with 705. Any more treatment and the room will become to dead.

I may have to find a different route as the 1/3 octive eq is not accurate enough and from the initial test, the areas I need to adjust often lay between sliders. I'm hoping that there is a unit made by someone out there where I can digitaly tune to an exact frequency and then adjust it. I've never ventured into 'pro audio' gear like this stuff before so it's a bit new to me.

You are quite correct on how roomeq gets very messy trying to do readings like this. Pretty much everything over 1k is all over the place. I'm guessing that there may be other software out there that is more suited to measuring the high end, just not sure where to start.

[shawn]

brucek wrote:

Mmm, I though a proggy was something you ate..

Anyway, hopefully you don't want to measure 'full range' much past 5KHz. The Radio Shack meter is not suitable for higher frequencies and would require investing in a better microphone or meter.

You'll find that measuring above sub frequencies results in a lot of comb filtering as shown in the response below (before and after), but can be cleaned up with the REW fractional octave averaging (smoothing) feature. The smoothing will reveal large deficiencies in levels that you may be able to