# Can't get this to work !



## Guest (Aug 2, 2006)

Hi there,

I apologize if this is not appropriate but I am having a lot of troubles getting ETF (not room eq wizard) to work properly.

I have a Genuis value 5.1 card that I bought a few days ago and I bought the necessary cables. But when I run the measurments to test the sound card, there is a lot of noise.

The mixer settings are okay. And if I change the sampling rate from 44khz to 48khz, there is very little change. To make matters worse, the levels between left and right channels change quite a bit if I wiggle the cables a bit.

I have basically connected the left input to the left output and the right input to " " " just to test the sound card out. I have spoken to Doug and he is also a little unsure of what to do.

If I check the signal to noise ratio on the graph, it reads at best, 2 dB. Doug tells me that the reading should be around 20 dB.

Help !

--Sincerely,


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## Danny (May 3, 2006)

Vaughan Odendaal said:


> Hi there,
> 
> I apologize if this is not appropriate but I am having a lot of troubles getting ETF (not room eq wizard) to work properly.


If you have a question please ask, hopefully we'll be able to help you



> The mixer settings are okay. And if I change the sampling rate from 44khz to 48khz, there is very little change. To make matters worse, the levels between left and right channels change quite a bit if I wiggle the cables a bit.


Depending on the speakers in your system the change from 44khz and 48khz may be hard to hear. RE the cables it sounds to me like you have a dodgy connection somewhere, possibly in the cables but it also could be elsewhere (sound card, source etc) maybe try replacing the cables then go from there.

Hope this helps

D.


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## JohnM (Apr 11, 2006)

Have you selected the Genius card to be your default device for sound playback and sound recording? (Audio tab of the Sounds and Audio Devices properties in the Control Panel). Which output are you using on the card? Although you say the mixer settings are OK, that is where many problems occur especially with multi-channel cards - does the Genius card have its own mixer? Maybe worth posting screenshots of the settings. What sort of cables are you using the make the loopback connection?


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## Guest (Aug 3, 2006)

Alright. Thanks for asking these questions. Let me be more specific. I am just the front out and line in connections to do a loop thru. I take a duel RCA male to male and plug into a duel female to 3.5 mm computer jack.

I don't know if you know of my sound card, but it was a low cost, cheap sound card and Doug from ETF told me that it should work. A number of other people I corresponded with said the same thing.

It is a full duplex card. And to answer your questions, yes, my sound card does have it's own seperate mixer. I'm not sure what that must be set to but I am also using the windows mixer. That is the main mixer that I am currently using.

What worries me is that the levels between right and left channels jump by about 4-5 dB with just a little wiggle from the cable. Now I've replaced these cables with much longer duel RCA's and the problem remains the same.

Perhaps it is the duel female to 3.5mm computer jack which is somehow corrupt ? I'm not sure. But Doug from ETF told me that he has never seen the kind of problems that I'm experiencing in his entire life. 

That isn't good. I will post some measurements. Again, I apologize because I know that this forum is for room eq wizard. Does anyone have experience with this acoustic program ?

BTW, I also downloaded room eq wizard too. I will post some measurements to show you what I'm talking about. Thanks for wanting to help.

--Sincerely,


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## brucek (Apr 11, 2006)

> I don't know if you know of my sound card, but it was a low cost, cheap sound card and Doug from ETF told me that it should work


Hard for us to know if you don't tell us what the sound card is?



> What worries me is that the levels between right and left channels jump by about 4-5 dB with just a little wiggle from the cable.


Does your soundcard have the standard line-in and line-out stereo 1/8" jacks on it that either of the (1/8" stereo to RCA adapters) shown below can plug into?


















If so, you would be better to use the wire type shown instead of the heavier adapters since they place much less strain on the soundcard connector. The connector on the soundcard is pitifully inadequate and prone to poor connectivity. The less strain you put on it the better.

As I remember, ETF use to require the loopback cable hooked up all the time during measurement (unlike REW that uses it once to obtain a compensation calibration file). Is it still this way?



> BTW, I also downloaded room eq wizard too


It's a lot easier to use in my opinion.

brucek


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## Guest (Aug 3, 2006)

Thank for replying !

*Hard for us to know if you don't tell us what the sound card is?*

Sorry, it's called the "Genius Sound Maker Value 5.1".

*Does your soundcard have the standard line-in and line-out stereo 1/8" jacks on it that either of the (1/8" stereo to RCA adapters) shown below can plug into?*

Yes it does.

*If so, you would be better to use the wire type shown instead of the heavier adapters since they place much less strain on the soundcard connector.*

I have both of those adapters. The bottom adapter shown in the picture you posted I couldn't use to connect the duel RCA's because both my line in and front out are next to each other.

So it is impossible for me to use those connectors because of the width of the connector. So instead, a computer guy recommended that I use cables instead. So he made up a duel female to computer jack.

*The connector on the soundcard is pitifully inadequate and prone to poor connectivity. The less strain you put on it the better.*

Thanks for the advice. I have tried the duel female to computer jacks and I've also tried using duel RCA male to male cables (6 m long) to do a loop thru. Both cables give the same result.

*As I remember, ETF use to require the loopback cable hooked up all the time during measurement (unlike REW that uses it once to obtain a compensation calibration file).*

It is only required to test the sound card. Once sound card has been tested the loop thru is no longer needed. 

*It's a lot easier to use in my opinion.*

Any advantages to ETF ? Can it measure to a better or similar resolution ? How do I do a sound card measurement with REW ? Is it the same way with ETF ? I'm not sure.

I conversed with Doug and he now thinks that my sound card could be at fault. According to him, "_It just may be that this particular card will not work because it has separate oscillators for input & output. They may be using an old chipset to
keep the price low_".

I really do not want to buy another card. I just bought this one a few days ago.

Thanks.

--Sincerely,


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## JohnM (Apr 11, 2006)

Vaughan Odendaal said:


> So instead, a computer guy recommended that I use cables instead. So he made up a duel female to computer jack.


Worth checking the workmanship, might have a bad joint in that cable.



Vaughan Odendaal said:


> *As I remember, ETF use to require the loopback cable hooked up all the time during measurement (unlike REW that uses it once to obtain a compensation calibration file).*
> 
> It is only required to test the sound card. Once sound card has been tested the loop thru is no longer needed.


The left channel must always remain connected as a loopback with ETF.



Vaughan Odendaal said:


> Any advantages to ETF ? Can it measure to a better or similar resolution ? How do I do a sound card measurement with REW ? Is it the same way with ETF ? I'm not sure.


REW measures to higher _potential _resolution, in both cases the resolution is dependent on the gate times you use - the longer the gate time, the higher the frequency resolution (simply reciprocal, 100ms gate time means 10Hz resolution, 1000ms gate means 1Hz etc. REW displays this figure for you). In most situations the measurement signal-to-noise cannot be made high enough for gate times much above 1 or 2 seconds. REW makes prettier waterfalls :blush: and makes it easier to read values from the graphs. ETF calculates many more acoustic parameters than REW. The help files explain how to make soundcard measurements etc, you can read them online here.


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## Guest (Aug 3, 2006)

Are you the man behind REW ? 

--Sincerely ?


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## Guest (Aug 3, 2006)

I don't understand what you mean by higher "potential" resolution. I have been told that ETF can resolve information down to 0.7 hz. 

I don't know what kind of resolution REW resolves to. The one thing I don't like about ETF is that the graphs like a bit ugly. On the other hand, the graphs and colours on REW and RTA look much, much better.

--Sincerely,


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## Guest (Aug 3, 2006)

*Worth checking the workmanship, might have a bad joint in that cable.*

How does one know if the cables are "okay" ? Thanks.

--Sincerely,


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## brucek (Apr 11, 2006)

> How does one know if the cables are "okay" ? Thanks


As long as they are not molded type connectors, you can simply do a visual inspection once you unscrew the body from the plug to expose the wires. Ensure no shorts and that the connections are well soldered. The tougher connection is with the 1/8" stereo plug. They're small and friggy to solder and easy to make a mistake.

You of course can simply check them with a meter if you have one also.

brucek


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## Guest (Aug 3, 2006)

Do you mean a multimeter ? How does one check these things out ? Sorry, I'm not that experienced when it comes to checking cable consistency. 

Thanks. Because I would like to try and find out what could be the cause of the bad noise in my graphs. There are a few things :

Either it's the sound card, the cable that connects to the computer jack, the mixer settings haven't somehow been set up properly, or perhaps my own sound card mixer (the mixer that comes with the card) needs to be disabled ?

Currently it's enabled.

How does one rule out these things ? Trying to be all Sherlock Holmes.  Heh.

--Sincerely,


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## JohnM (Apr 11, 2006)

Vaughan Odendaal said:


> Are you the man behind REW ?


Yes, that's me.



Vaughan Odendaal said:


> I don't understand what you mean by higher "potential" resolution. I have been told that ETF can resolve information down to 0.7 hz


The internal processing resolution of REW is 0.366Hz when using a 48k sample rate. This is determined by the FFT lengths used when generating the frequency responses, 128K in REW's case. However, the true resolution of a frequency response plot is determined by the duration of the section of the impulse response analysed to produce it. For 0.366Hz resolution you need to analyse a 2.73s period of the impulse response (or 1.4s for 0.7Hz). If you only analyse a 100ms portion of the impulse response, the resulting frequency response has only 10Hz resolution, no matter how large an FFT you apply to the (padded) data. To put this another way, you would not be able to see individual peaks that were less than 10Hz apart, they would be merged together. To have more time resolution you need to analyse a longer time period of the impulse response. 

If you look at impulse responses, they are initially large and then decay away until they reach the noise floor of your measurement. Once the impulse response has fallen below the noise floor you can no longer use it to provide information about the frequency response, including data which is only noise degrades your frequency response result. To get the best frequency response, the impulse response is "windowed" to select the portion from the start of the response until it decays below the noise - this window is also referred to as a gate, and its length is referred to as the gate time. If the noise level is high, it may only be a few hundred milliseconds until the response is lost in the noise, so that measurement can never offer frequency resolution better than a few Hz. If the noise level is very low the response will be discernable for much longer and so you can use more of it and get higher frequency resolution.

The noise level in the impulse response can be reduced by using a higher sound level for the measurement sweep, ensuring the background (acoustic) noise is low, using pre-amplifers and soundcards with high signal-to-noise ratios, using longer sweep times and carrying out synchronous pre-averaging of multiple measurements (those last two will be available in the next release of REW, coming soon )


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## Guest (Aug 3, 2006)

John, I'm glad I'm speaking to the guy behind the software. It helps matters greatly.

So with REW, I need to check sound card FR using my SPL meter ? Is there any other way of testing REW just for sound card problems without using an SPL meter ?

I have one but I don't think I have the necessary cables to do the test. I have two RCA male to male cables (to connect left and right front out and line in) and two female to computer jack cables that allow me to rig up the RCA's.

John, I need to ask you a question ; what is the cost of REW ? I downloaded the demo version I assume. Concerning the steps that I need to take to take the quality of the sound card out of the equation, what would I need to do ?

Thanks for your advice.

--Sincerely,


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## brucek (Apr 11, 2006)

> Do you mean a multimeter ? How does one check these things out ? Sorry, I'm not that experienced when it comes to checking cable consistency


Yes, a multimeter on the lowest resistance setting, checking for continuity and opens and shorts. Test that the sleeve of each RCA connects to the sleeve of the 1/8" stereo plug and isn't shorted to the center pin of either RCA plug or either the tip or ring of the 1/8" stereo plug. Check that the tip of the 1/8" stereo plug connects to the center pin of one RCA plug and no other and check that the ring of the of the 1/8" stereo plug connects to the center pin of the other RCA plug and no other......



> So with REW, I need to check sound card FR using my SPL meter ?


No, you check the soundcard response by shorting one channel of the soundcards output to its input and saving a calibration file for the soundcard (after a special test) to be used every time you use REW. See the HELP FILES on calibrating the soundcard. In fact, read the entire HELP file and all your questions will be answered...



> I need to ask you a question ; what is the cost of REW ? I downloaded the demo version I assume


The total cost is zero. You downloaded the full version. 

brucek


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## Sonnie (Apr 11, 2006)

brucek said:


> The total cost is zero. You downloaded the full version.
> 
> brucek


:shhh: Now why did you go and tell him it's free. Let me handle this please... :cunning: 


Vaughan... how much are you willing to pay? I'm sure we can work out an affordable payment schedule. :spend:


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## RollsRoyce (Apr 20, 2006)

It's also possible that the receptacles on the sound card have lots of play and aren't making firm contact with the plug when it's inserted. Depending on the construction of the receptacles-some are open and some are enclosed-you may be able to carefully bend the side contacts in a little with a small screwdriver. Just enough to firmly grip the plug. It's easier to do this with the card removed, which will also make sure you don't short anything out. Look for cold solder joints where the receptacles are attached to the sound card. Good solder joints look smooth and shiny, while cold joints are usually dull and/or dark. Sometimes there will be a tiny ring in the solder around the pin.


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## Guest (Aug 4, 2006)

Can REW measure modal ringing too ?

I just wanted to ask you, or John something. How would I be able to rule out the sound card as the culprit for the bad measurements ? Because I may buy another card. The salesman that sold me the card told me that I could return it, so I might get the Sound Blaster Live Value 5.1 card.

But that card is 2.5 times the price. Please give me some steps to check so that I know for certain that my card is not up for the task. Thank you very much !

--Sincerely,


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## brucek (Apr 11, 2006)

> Can REW measure modal ringing too ?


REW calculates both Spectral decay and Waterfall Plots. Waterfall plots reveal modal ringing. Please see the *HELP FILES*. 












> Please give me some steps to check so that I know for certain that my card is not up for the task


If it is full duplex and has line-in and line-out stereo connectors, then it's up to the task. Thats what the soundcard calibration file is for. See the *HELP FILES* on calibrating the sound card... 

brucek


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## Guest (Aug 4, 2006)

Yeah, my card is full duplex. But the readings that my card is giving me is wacked out.  There is noise on the flat line in the graph in ETF. There shouldn't be.

Perhaps I should measure my sound card with REW to show you. I read through the help but I would still like a little help to get me ready to get my sound card calibrated. I do want to show you the results as quickly as possible and I could use as much help as I can get. 

I have the cables (I think). If I do a loop thru with REW and go test sound card, it tells me that I must set the levels for my SPL meter. I don't have to do that with ETF.

I was under the impression that the SPL meter would only come into play when measuring the actual room, and not just the sound card. 

So basically, it's like this; if I connect the left input to left output and right input to right output then what exactly do I need to do next ? The mixer settings as described in the help file is self explanatory but then what do I need to do to test the sound card ?

I'm really sorry if I'm messing you around, but sometimes I like to get confirmation on what I'm supposed to do. A nasty habit I suppose. 

Thanks a lot !

PS (John, if you're there, how would the Sound Blaster Live Value 5.1 sound card work ? Is it a good card to buy, if, indeed, my card is messed up ? )

--Sincerely,


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## brucek (Apr 11, 2006)

> There is noise on the flat line in the graph in ETF. There shouldn't be.


That's correct. Sounds like you may have the card in a monitor mode where the line-out is being fed back to the line-in. Don't be so quick to discard the soundcard. Find the fault and you'll be fine.

As you say, why not use REW since we're a lot more knowledgeable about it. I'm sure we can solve your problem and save you some money.



> So basically, it's like this; if I connect the left input to left output and right input to right output then what exactly do I need to do next ? The mixer settings as described in the help file is self explanatory but then what do I need to do to test the sound card ?


Nope. You do not connect left to left and right to right. REW always uses one channel only. The soundcard is first setup with a short from output to input and then a soundcard calibration file is saved. After that we remove the short and the saved file is then used by REW to compensate for any inadequacies in the soundcard and so we only input and output on a single channel (but we still need to use stereo adapters on the card itself), as shown below.










:surrender: I sure wish I could get you to read those Help files, but in lieu of that I will direct you to a step by step use of REW I posted a while back. Specifically it will get you through the soundcard setup anyway.

READ THIS PART OF THIS THREAD

brucek


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## Guest (Aug 4, 2006)

Thanks !

--Sincerely,


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## Guest (Aug 4, 2006)

Okay. I did as you suggested. I connected the right input to right output. I clicked "sound card calibration" and used the default setting -6 db. I also used the settings recommended in the help file to set the levels in playback and recording windows.

Right. I am getting quite a bit of noise in the graph. I'll post a pic in a few minutes. I need to find a way to post pictures quickly. I'm using imageshack to host files.

Thanks.

--Sincerely,


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## brucek (Apr 11, 2006)

> I need to find a way to post pictures quickly


Here's a step by step of how to post an image here at the Shack.



> I am getting quite a bit of noise in the graph.


I bet there is a monitor loopback in the mixer settings somewhere..

brucek


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## Guest (Aug 4, 2006)

I also tried changing channels. Just to see what would happen. So I tried the left channel in the menu and changed the cables as well.

It told me that the input channel had a RMS value of -35 which is higher than what it should be. It says "it may be that the sound card has high amounts of noise". 

With the right channel, it does not say this.

I tried the measurements again and this time the result was flatter with less noise. I don't know how and I don't know why, but the result is much better than what it was.

--Sincerely,


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## Guest (Aug 4, 2006)

This is the first graph :










This is the second graph :










Please report back. Thanks.

--Sincerely,


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## Guest (Aug 4, 2006)

Keep in mind that I have not calibrated the SPL meter. I have not connected cables to my amp yet. I just have connected line in to line out as specified in the thread.

--Sincerely,


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## Guest (Aug 4, 2006)

The cables I have connected to the sound card are two seperate RCA female to computer jack. From there I connect the male RCA to female to complete the loop thru. 

Now, right now, I just swapped the one RCA female to computer jack and used one duel RCA _connector_. So one connector and one cable. Have no idea what this would do (or not).

You see, I cannot fit both connectors into my sound card because the width of both connectors overtake the line in and front out connections. I mean, they are situated so close to one another.

Any difference in using duel RCA connectors to the cables I'm using right now ?

I hope I have everything connected as it should.

--Sincerely,


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## Guest (Aug 4, 2006)

I also noticed that once or twice the program has told me that my impulse measurements are not where they should be. "Check impulse graphs or something like that".

I don't know what that is supposed to mean or how to rectify the problem. Help would be appreciated.

I hope all my questions can be answered. 

--Sincerely,


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## Guest (Aug 4, 2006)

One last thing before I hit the sack, I don't own a BFD and I hope to same day soon. Do I connect up my cables to the amp in a different way because I don't have the BFD or is it the same as described in your thread ?

Thanks. I'm going to bed, it's really, really late. Heh. Thank you very much.

Cheers.

--Sincerely,


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## brucek (Apr 11, 2006)

The only connection that is allowed for the soundcard calibration is a single loop from line-out right to line-in right.

This can only be accomplished by using a stereo 1/8" adapter plug as I previously showed. Many people have trouble with the big goofy one and correctly use the wire type such as this:









Note that the single male plug end shown above is *stereo* and the two tails are mono left and right. Plug two of these adapters into the line-in and line-out. Then connect a single cable between the right tails and leave the left unconnected.

Now do the soundcard calibration. No SPL meters, no nothing else, just the soundcard calibration. 



> Do I connect up my cables to the amp in a different way because I don't have the BFD or is it the same as described in your thread ?


Just hook up as normal without a BFD. Soundcard Line-out right channel from the adapter to the receiver AUX input left or right channel. (I actually use a Y splitter there so I can hook up left and right AUX input to my receiver for other testing).
And hook the SPL meter to soundcard line-in right adapter.




> also noticed that once or twice the program has told me that my impulse measurements are not where they should be. "Check impulse graphs or something like that".


We'll ignore that stuff until you go through the complete step by step setup of REW.

brucek


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## Guest (Aug 5, 2006)

I have the same kind of cable except on the other end it is not male, but female. Then I have seperate RCA's that plug into the females.

So, yes, I have connected to REW as you described.

What do you think of the graphs I posted ?

--Sincerely,


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## brucek (Apr 11, 2006)

> What do you think of the graphs I posted ?


It looks like the graph you get when you have no loopback connected. But REW will tell you that it can't find the loopback during the soundcard calibration test, so that's not the problem. Although you can see by the readout in the tab that the target is -6dB and you're basically getting no signal at -34dB IN.

I can only think it's a feedback problem from a recording monitor feature turned on in your soundcards mixer settings. Have you checked the settings for any record monitor feature selected? Offtimes they name them something weird like "what you see", etc.

This has to be corrected before you can carry on.

Perhaps John can comment on your graph - he's seen lots of these.

brucek


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## Guest (Aug 5, 2006)

Hi brucek,

What you hear slider ? I'm not sure what that is supposed to mean. I looked in my mixer settings and I don't see a control like that.

Where about would this be ? Does windows have this feature and where would I go to turn it off ? 

I hope this sound card is not the problem but at R120, it is dirt cheap. Perhaps it was too cheap for a reason. I'm not sure. 

Thanks.

--Sincerely,


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## brucek (Apr 11, 2006)

> I looked in my mixer settings and I don't see a control like that.


I'm referring to the software supplied by the card itself that provides its own options. You can usually find it in the Windows control panel. For example, see this thread about another card where John discusses the setup. You will have a setup for your specific card in your software.

brucek


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## JohnM (Apr 11, 2006)

Stange-looking graph indeed, Vaughan. If you select the "Impulse Response Controls" graph group in the top right corner instead of "Filter Adjustment" would be intersting to see what the response looks like, you can save just the graph by clicking on the small disk icon in the bottom left corner of the graph. The problem probably lies in the mixer settings for your soundcard, many features have no corresponding control in the Windows mixer - in particualr, some acoustic effect may be turned on. If you post some screenshots of the soundcard's mixer and whatever other control applications it has (maybe some effects control panels) we may be able to spot the problem from those.


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## brucek (Apr 11, 2006)

> Stange-looking graph indeed,


Although, if I take the PC I'm working on right now without any loopbacks on it and run the soundcard cal, I get a graph that looks quite similar (see below). 

Of course, REW told me that I have no loopback on, but it may be a clue that he is not receiving what he transmits at all.










brucek


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## Guest (Aug 7, 2006)

If I connect the right channel, it does not tell me that I don't have a loop back. So that isn't the problem.

Doug, I will post some pictures of mixer settings. I'm not entirely sure what I should do with the mixer that came with my soundcard. At the moment, all channels are at maximum level.

So perhaps you could advise me on what to do with mixer levels for my sound card. The windows mixer settings are pretty much as you recommend it.

Thanks again. 

--Sincerely,


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## Guest (Aug 7, 2006)

Although I have a sneaking suspicion that my sound card is at fault. Doug from ETF tells me that my sound card probably has a very old chipset.

--Sincerely,


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## terry j (Jul 31, 2006)

Hi vaughan, this thread just suddenly sropped. Did you ever get it sorted?? I have exactly the same card as you had here, with an almost exact replica of the graph when you check the soundcard.

Please let us all know if you solved it, and the steps taken to do so.

Kind regards

terry


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## JohnM (Apr 11, 2006)

Terry, can you post screen shots of your windows mixer settings for record and replay when REW is running?


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## Guest (Oct 25, 2006)

Hi Terry,

Nope, I never got this sorted out. I kind of gave up. I really do think that my sound card is at fault. Doug thinks it is too. I sent the pics I provided to Doug and he believes that the chipset that my card is using is simply outdated.

I think I'm just going to buy a Creative MP3 sound card because that card apparently has no problems at all with these programs. I am sorry for not updating the thread but I really did try everything *I* could.

If there are any other procedures I could try to possibly get this to work then I'll try it.:explode: 

--Sincerely,


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## terry j (Jul 31, 2006)

hi vaughn, 
can understand never sorting it out, don't think mine is 'sortable' either. However, if you look at the thread I started (wierd results when using calibrating, need new soundcard?) - or something like that, just look for terryj- you'll see that with the help of the guys here ( whaddaya mean 'with the help'?? they were absolutely essential and marvellous!:jump: ) I managed to use the soundcard we have and get useful and valid results up to about 1000hz, can't really remember the exact figure.

Look it up, and follow it, what was applicable to my soundcard is surely applicable to yours and you can get moving on it even though you don't have a new soundcard.

I am currently borrowing a friends creative soundblaster usb card, will soon let people know how it's going back in that thread.

In the meantime, use the card you have and get moving!!:T 

lots of love

terry


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