# Soundcard setup for rew



## marty1 (Jun 29, 2010)

I am having great difficulty trying to get my soundcards settings correct on my laptop so I can measure with REW.

First of all I could hear feedback through my speakers and the sound of my own voice being picked up by the spl?

I guessed this was wrong so I tried going into soundcard settings tweaking a few things but now the spl reading on the REW screen is not registering anything at all??

There is no options on the laptop to go back to default settings and the trouble is there is so many settings I am unsure what needs setting as what, bear in mind I am a newbie to soundcards and REW.

The pictures attached are what I am up against, I would really appreciate it if someone could tell me what all the settings need to be for all the options.

Thanks


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## Wayne A. Pflughaupt (Apr 13, 2006)

Offhand I’d say you need to make sure you have “Line In” selected and not “Mic In.” I can’t tell for sure from your pictures which way you have it set.

Also, in the “Microphone/Line In Properties” tab, uncheck the “Listen to this device” box.

Regards,
Wayne


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## marty1 (Jun 29, 2010)

Wayne A. Pflughaupt said:


> Offhand I’d say you need to make sure you have “Line In” selected and not “Mic In.” I can’t tell for sure from your pictures which way you have it set.
> 
> Also, in the “Microphone/Line In Properties” tab, uncheck the “Listen to this device” box.
> 
> ...


It was originally in the recording section on the soundcard screens I made all the adjustments in and have somehow stopped the rew screen being able to read an spl measurement, when checking levels using spl it says level is OK but when I actually try and take a measurement the spl reading at the top of the screen does not move?

The attached screen is the recording section, the same as the playback section you have enable and disable options, listen to this device options, level options for each section i.e. Microphone/line in selection has microphone boost level and line in level, options to set each selection as default device or default communications device and advanced section which allows you to chance sound quality, I have everything set to dvd 16bit quality.

As something in the recording section has affected the spl I need to know what each section has to be enabled and disabled, set as default and default communications device and what levels to have the selections at, the same goes for the playback sections if they are relevant?

Thanks for your advice, I would appreciate it if you could let me know what I need to do.

Kind Regards
Marty


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## marty1 (Jun 29, 2010)

Can anyone help at all as I would really love to start measuring but I want to be sure it is accurate :help:


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## Wayne A. Pflughaupt (Apr 13, 2006)

Can you show us your REW settings box?







​

Regards,
Wayne


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## marty1 (Jun 29, 2010)

Wayne A. Pflughaupt said:


> Can you show us your REW settings box?
> 
> 
> View attachment 23710​
> ...


This is what I currently have it set at, but apart from being able to hear my own voice through the speakers via the spl meter it seemed to record the sounds better than it does now, when I say better I mean at least it was able to read something :rolleyesno: It just made it worse when I tampered with the recording section on the soundcard settings :scratch:

I really hope you can help cos I am lost!

Kind Regards
Marty


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## Wayne A. Pflughaupt (Apr 13, 2006)

Perhaps you can find some information on this thread. It has some pictures and info that ties the REW Settings window functions to the soundcard functions. 

Regards,
Wayne


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## marty1 (Jun 29, 2010)

Wayne A. Pflughaupt said:


> Perhaps you can find some information on this thread. It has some pictures and info that ties the REW Settings window functions to the soundcard functions.
> 
> Regards,
> Wayne


Thats great, I have a rough idea on what to try but reading it I am now not sure if I have it connected correctly :rolleyesno:

I only have 2 leads, 1 headphone jack from front out socket on soundcard to red and white audio leads connected to amp. 1 headphone jack from line in socket on soundcard to spl meter with just the white lead connected, the red lead loose. The thread suggests using splitters or something, not sure what they are?? Also the red lead connected to spl??


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## kflory (Feb 6, 2010)

While I did not read the thread, I think I can answer...



marty1 said:


> The thread suggests using splitters or something, not sure what they are??


This refers to a Y adapter to split the signal from one channel to two. 

This is not the most ideal picture, but here is a picture of my setup and it is shown here top/to the left (not a great angle):











marty1 said:


> Also the red lead connected to spl??


Depends on your selection for the Soundcard preferences as you can select Left (White) or Right (Red):


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## marty1 (Jun 29, 2010)

kflory said:


> While I did not read the thread, I think I can answer...
> 
> 
> 
> ...


The 2 leads I use that are headphone jacks direct to red and white audio leads, are these ok to use?


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## marty1 (Jun 29, 2010)

I now have settings on my soundcard to this : On playback section I have enabled speaker/headphone with speaker level at halfway and microphone and pc volume muted, the section that just says speakers I have it enabled, set as default device with volume control halfway, line in muted and microphone muted. Finally on playback section I have enabled digital output.

On recording section I have microphone/line enabled, line in at halfway and microphone boost off. The line in option I have enabled and set as default device and the line in level halfway up. Stereo mix I have enabled and mix volume set at halfway up.

All other selections I have disabled, it seems to be working ok but the problem I now have is when I check levels on measure section it now complains about clipping, when I turn the amps master volume down the clipping complaint goes but I can barely hear any sound coming from the speakers?? What is going on now?

I would really appreciate more help please:help:


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## JohnM (Apr 11, 2006)

Disable stereo mix in recording, it creates an internal feedback path from playback to record.


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## marty1 (Jun 29, 2010)

JohnM said:


> Disable stereo mix in recording, it creates an internal feedback path from playback to record.


Ok I have done this but the clipping is still there, also the measurement that it does record seems too perfect so I am certain this is not recording properly :huh:


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## JohnM (Apr 11, 2006)

What range do you have the SPL meter set to?
Do you have a connection that goes directly from one output channel back to one input channel? If so, disconnect it.
When you make a measurement, which of the REW input level meters do you see changing, left or right?
Which input have you told REW to listen to in the soundcard settings?
What is the exact text in the clipping warning message and what does it say in the title of the clipping warning window?


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## marty1 (Jun 29, 2010)

JohnM said:


> What range do you have the SPL meter set to?
> Do you have a connection that goes directly from one output channel back to one input channel? If so, disconnect it.
> When you make a measurement, which of the REW input level meters do you see changing, left or right?
> Which input have you told REW to listen to in the soundcard settings?
> What is the exact text in the clipping warning message and what does it say in the title of the clipping warning window?


I have spl set to 70db reading

I have headphone jack in line out (there is no line out on my soundcard only front out which i assume is the same) to red and white male audio leads connected to video1 input on amp and headphone jack connected to line in on soundcard to spl meter, red male audio lead connected, white lead hanging loose.

When measuring its the right equaliser that moves, left and out stay still, left equaliser stays at -21 and out stays at -12

On soundcard settings it is set to input channel right

Here is the clipping message that appears

Thanks for looking into this, I really appreciate it


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## JohnM (Apr 11, 2006)

It is odd that the left input is sitting at -21 during a measurement when you have nothing connected to the left input, that would suggest there is an internal path active (like that stereo mix setting). You will need to track that down. One way to do it would be to turn on the REW signal generator with a 1kHz sine wave at -12dB, but unplug your front out connection first as you do not need to hear the tone. Use the REW VU meters to watch the input level REW is seeing when the tone is playing. Work through the recording settings to see what results in the input on the left channel going away.

Once that is sorted out set the SPL meter to the 80dB range and try again. If the level ends up a bit low you may need to increase the line in volume setting, but try with it as is first. 

You will also need to calibrate REW's internal SPL meter against your external meter so that REW draws its graphs at the right level, but leave that until you are able to get good measurements as changing the line in volume (or the SPL meter range) would mean re-doing the REW SPL meter cal.


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## marty1 (Jun 29, 2010)

JohnM said:


> It is odd that the left input is sitting at -21 during a measurement when you have nothing connected to the left input, that would suggest there is an internal path active (like that stereo mix setting). You will need to track that down. One way to do it would be to turn on the REW signal generator with a 1kHz sine wave at -12dB, but unplug your front out connection first as you do not need to hear the tone. Use the REW VU meters to watch the input level REW is seeing when the tone is playing. Work through the recording settings to see what results in the input on the left channel going away.
> 
> Once that is sorted out set the SPL meter to the 80dB range and try again. If the level ends up a bit low you may need to increase the line in volume setting, but try with it as is first.
> 
> You will also need to calibrate REW's internal SPL meter against your external meter so that REW draws its graphs at the right level, but leave that until you are able to get good measurements as changing the line in volume (or the SPL meter range) would mean re-doing the REW SPL meter cal.


Sorry but I am not sure how to do that, I am a bit of an amatuer at this as you may have noticed :rolleyesno:


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## marty1 (Jun 29, 2010)

marty1 said:


> Sorry but I am not sure how to do that, I am a bit of an amatuer at this as you may have noticed :rolleyesno:


I have got it :T

In the line in level selection there is a box that says balance, i clicked on that and it had 2 volume bars, bar 1 and bar 2, I assumed this was left and right, turned 1 down so now there is nothing registering in the left equaliser! Is this how I should leave it?

So now on the soundcard everything is disabled apart from in playback area the speakers section I have both left and right turned up full and in recording area I have line in enabled with just the right volume up and left down?

Is this right now?


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## marty1 (Jun 29, 2010)

I have tried the check levels and it is still complaining about too high volumes, even though the amp volume isnt that loud? The right channel equaliser just floats around -18db even when I havent starting checking levels, when I switch the spl meter off and then check levels it says level is ok?


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## laser188139 (Sep 19, 2009)

When you see the clipping warning, have you tried reducing the input level in REW or the soundcard and re-doing the Check Levels process? 

The fact that the amp volume does not seem that loud is a separate question. What does it read on the analog dial of your external SPL meter?

The clipping warning in REW is referring to something different, the digital levels going to and coming from the soundcard, relative to the maximum digital level supported by the soundcard interface. If you increase the volume control on your receiver, so that the amp is putting out a louder sound, by reducing the volume/gain setting on the input channel you can keep the signal at the same digital level in the computer. 

It's a little curious that you see a balance control on the Line In level selection. On my laptop, I see that on the laptop's built-in mic array, but not when I am using the mini-stereo Line In mic input. But this is probably just how your soundcard's driver software was written. The impression I have looking at the balance control on my mic array input is that it just lets me fine tune the gains of the two input channels separately, if I have the need to do this. So you can leave it lower for the left channel if you like; you will certainly know then that it is not your left channel input that is causing you problems. 

Bill


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## JohnM (Apr 11, 2006)

Are you using an external soundcard connected by USB or the internal soundcard of the PC? Your initial post shows both present, some of your screen captures look to be of settings for the USB card and some are of the internal soundcard.


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## marty1 (Jun 29, 2010)

JohnM said:


> Are you using an external soundcard connected by USB or the internal soundcard of the PC? Your initial post shows both present, some of your screen captures look to be of settings for the USB card and some are of the internal soundcard.


Its an external soundcard with usb connection, the laptop only has mic in and headphone out sockets, I am not sure how to access settings for internal soundcard, i have just been going into devices and printers and click on usb sound device? The volume that is affecting the clipping is the right equaliser, it goes right up into the red area.

How do i adjust input level on rew?


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## Wayne A. Pflughaupt (Apr 13, 2006)

marty1 said:


> Its an external soundcard with usb connection, the laptop only has mic in and headphone out sockets, I am not sure how to access settings for internal soundcard...


If you're using an external sound card, you don't need to fool with any settings for the internal sound card. Just select the external sound card in the Settings Window, "Soundcard" tab.




> How do i adjust input level on rew?


That information, complete with pictures, was in the link I provided in Post #7.


Regards,
Wayne


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## marty1 (Jun 29, 2010)

Wayne A. Pflughaupt said:


> If you're using an external sound card, you don't need to fool with any settings for the internal sound card. Just select the external sound card in the Settings Window, "Soundcard" tab.
> 
> 
> That information, complete with pictures, was in the link I provided in Post #7.
> ...


Thanks

I will have another look through the link, I cant find anything on the laptop that shows external sound card, when i connect soundcard it just pops up and devices and printers as external usb device, when i click on that icon it brings up the screens i have been going through on this thread


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## Wayne A. Pflughaupt (Apr 13, 2006)

Are you saying that you don’t have an option to select the USB sound card in the Input/Output Device drop-down windows in REW’s Settings window/Soundcard tab? It should either say something like “USB Audio” or the name of the Soundard itself (Realtek, etc.).







​

Regards,
Wayne


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## marty1 (Jun 29, 2010)

Wayne A. Pflughaupt said:


> Are you saying that you don’t have an option to select the USB sound card in the Input/Output Device drop-down windows in REW’s Settings window/Soundcard tab? It should either say something like “USB Audio” or the name of the Soundard itself (Realtek, etc.).
> 
> 
> View attachment 23731​
> ...


Sorry Wayne I thought you meant select it via the laptop :coocoo:

So this is what I have done, I turned the input volume down lower (not as low as what the attached picture is showing!) and it is now saying level is ok 

The only thing is now when i check levels on before i do the test tone the equaliser bars are showing sounds around -30db mark, when I actually check the levels only the right 1 goes up but the left stays at -30 as that is not the channel I am using but I am assuming now rew is controlling volume as i cant turn left volume down on soundcards line in selection anymore. Is this still ok to measure now that levels are ok or will it corrupt results?

Thanks
Marty


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## Moonfly (Aug 1, 2008)

Only the right channel should be showing because only the right phono is going to the spl meter, so thats a result :T

The -30 level sounds a bit low, mine is usually about -18 to -16. Does REW say the level is low or ok, I will assume low. You need to increase the line in volume a little on your sound card till the level comes up to an ok level, or possibly even the volume output on your computer. Between them you should get your levels upto where they need to be, and then you should be good to go, hopefuly 

If you run at -30 I would expect REW to report insufficient signal.


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## marty1 (Jun 29, 2010)

Moonfly said:


> Only the right channel should be showing because only the right phono is going to the spl meter, so thats a result :T
> 
> The -30 level sounds a bit low, mine is usually about -18 to -16. Does REW say the level is low or ok, I will assume low. You need to increase the line in volume a little on your sound card till the level comes up to an ok level, or possibly even the volume output on your computer. Between them you should get your levels upto where they need to be, and then you should be good to go, hopefuly
> 
> If you run at -30 I would expect REW to report insufficient signal.


It says level ok, just my concern is should there be anything in the equaliser bars before I even run check level tone, the green equaliser bars are both hovering in the -30db area, I would have thought there should be nothing in left channel and the right goes up when tone begins?

This is before i have even run a tone:

Thanks
Marty


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## Moonfly (Aug 1, 2008)

Ensure the laptops internal mic is turned off. If not its likely picking up ambient noise, or the noise from your laptops fan. Either disable the mic, or turn its volume right down on the PC's own soundcard settings.


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## marty1 (Jun 29, 2010)

Moonfly said:


> Ensure the laptops internal mic is turned off. If not its likely picking up ambient noise, or the noise from your laptops fan. Either disable the mic, or turn its volume right down on the PC's own soundcard settings.


All the mic options are disabled, it is only speakers master volume on playback and line in levels on recording that are active?

The left channel is definately not picking up anything, it is dead still?


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## Wayne A. Pflughaupt (Apr 13, 2006)

Set “Output Device” to “Speaker,” not “Default.” Also it looks like you haven't performed a calibration of the sound card, or at least not loaded the file.










Regards,
Wayne


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## marty1 (Jun 29, 2010)

Wayne A. Pflughaupt said:


> Set “Output Device” to “Speaker,” not “Default.” Also it looks like you haven't performed a calibration of the sound card, or at least not loaded the file.
> 
> 
> 
> ...


Thanks Wayne

It wont let me adjust the second bar down of the output device, only the top bar which i have set to external usb as shown, the bar with default in is frozen, unless i am being thick again and missed something?

Also here is my soundcard cal result, not sure how good this is?

Regards
Marty


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## marty1 (Jun 29, 2010)

I know I wasnt supposed to do spl cal before doing this, does that affect the soundcard results?


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## JohnM (Apr 11, 2006)

marty1 said:


> I know I wasnt supposed to do spl cal before doing this, does that affect the soundcard results?


No, it doesn't affect the result, but the soundcard cal result is not right at the upper end. Whatever is causing the input to read levels before you even start the sweep needs to be fixed. 

1. Click the "VU Meters" button in the toolbar to bring up the VU meters
2. Turn on the REW SPL meter by clicking the red button, the VU meters should then become active
3. See what happens to the levels shown on the VU meters when you disconnect the cables from the soundcard
4. Post screenshots of the various tabs in the soundcard playback and recording device properties


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## Wayne A. Pflughaupt (Apr 13, 2006)

IWith my sound card, I found I had to push the input level a bit higher than REW recommends to get a good calibration. Maybe that’ll work for you too...

Regards,
Wayne


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## marty1 (Jun 29, 2010)

JohnM said:


> No, it doesn't affect the result, but the soundcard cal result is not right at the upper end. Whatever is causing the input to read levels before you even start the sweep needs to be fixed.
> 
> 1. Click the "VU Meters" button in the toolbar to bring up the VU meters
> 2. Turn on the REW SPL meter by clicking the red button, the VU meters should then become active
> ...


When i unplugged the leads the vu bars were still showing the a decibel level that doesnt move?

When I adjust the input mixer volume in rew settings screen that gets rid of them but I have to turn it down to 0

Here is the screens for the soundcards settings, the darker screens towards the end is the pc sound controls, not the soundcards I think :huh:

Sorry there is quite a few, I wanted to make sure there is nothing I have overlooked :R


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## JohnM (Apr 11, 2006)

To have an input showing on the USB line in with nothing connected is pretty wierd. The card may be faulty, which USB card is it?

Try enabling the built-in IDT audio and use that - the input called "microphone/line in" will automatically set itself up as a line input when it has your SPL meter or a loopback cable (for soundcard cal) plugged into it. Settings look OK for the IDT card.


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## marty1 (Jun 29, 2010)

JohnM said:


> To have an input showing on the USB line in with nothing connected is pretty wierd. The card may be faulty, which USB card is it?
> 
> Try enabling the built-in IDT audio and use that - the input called "microphone/line in" will automatically set itself up as a line input when it has your SPL meter or a loopback cable (for soundcard cal) plugged into it. Settings look OK for the IDT card.


I will give this a try, so just to check on the input volume on the rew soundcard settings screen even if i turn the volume right up there should be no green equaliser bars going up in conjuction with the volume being turned up if the spl is unplugged?

The soundcard is maplins own soundcard.

When you say enable the microphone/line in in idt do I still plug spl into external soundcard line in or into the laptop direct, bear in mind that the laptop only has a microphone port no line in?

Thanks
Marty


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## marty1 (Jun 29, 2010)

marty1 said:


> I will give this a try, so just to check on the input volume on the rew soundcard settings screen even if i turn the volume right up there should be no green equaliser bars going up in conjuction with the volume being turned up if the spl is unplugged?
> 
> The soundcard is maplins own soundcard.
> 
> ...


Is there definately sound being picked up through somewhere, if you look at the first picture 3 posts ago the left and right green equalisers are stationary, the do not move a mm no matter how much noise I make, when i do turn the spl meter on thats when the right bar starts to move up and down in conjuction with the sounds?

When I turn the input level on rew up or down that is the only time these green bars move up or down unless the spl is plugged in?

Thanks
Marty


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## JohnM (Apr 11, 2006)

marty1 said:


> When you say enable the microphone/line in in idt do I still plug spl into external soundcard line in or into the laptop direct, bear in mind that the laptop only has a microphone port no line in?


Yes, the "mic" port is actually a "mic/line" port.



marty1 said:


> Is there definately sound being picked up through somewhere, if you look at the first picture 3 posts ago the left and right green equalisers are stationary, the do not move a mm no matter how much noise I make, when i do turn the spl meter on thats when the right bar starts to move up and down in conjuction with the sounds?


It is not picking up sound, but there is some sort of signal there - more typical levels with nothing connected would be around -90dB. It may be that the input has a DC offset, but whatever the cause is it is not soemthing you should be seeing.


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## marty1 (Jun 29, 2010)

JohnM said:


> Yes, the "mic" port is actually a "mic/line" port.
> 
> It is not picking up sound, but there is some sort of signal there - more typical levels with nothing connected would be around -90dB. It may be that the input has a DC offset, but whatever the cause is it is not soemthing you should be seeing.


Ok Thanks for your help John, I will post the results as soon as I get a chance to try it :T

I was always under the impression that the mic port on a laptop should not be used for rew but if this works as a line in aswell thats great, just wish I hadnt got the soundcard now, bit of a waste.


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## marty1 (Jun 29, 2010)

JohnM said:


> To have an input showing on the USB line in with nothing connected is pretty wierd. The card may be faulty, which USB card is it?
> 
> Try enabling the built-in IDT audio and use that - the input called "microphone/line in" will automatically set itself up as a line input when it has your SPL meter or a loopback cable (for soundcard cal) plugged into it. Settings look OK for the IDT card.


Right I have connected the mic in to headphone out sockets on my laptop using a phono coupler, red leads connected either end, white leads hanging loose.

Good news, the volume bar problem is solved :bigsmile:

But I am not sure if the result is any good?

Thanks
Marty
View attachment 23812


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## JohnM (Apr 11, 2006)

Not quite what we are after, but getting there 

On the Windows sound -> recording -> Microphone/Line In -> Properties -> Listen tab make sure "Listen to this device" is not selected.


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## marty1 (Jun 29, 2010)

JohnM said:


> Not quite what we are after, but getting there
> 
> On the Windows sound -> recording -> Microphone/Line In -> Properties -> Listen tab make sure "Listen to this device" is not selected.


I am so glad to hear that:bigsmile:

Just to check, by windows you mean the idt control panel?

There is no listen to option I can find on the idt control panel, only when I go into usb setting is there that option there and that is definately disabled?

Thanks 
Marty


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## JohnM (Apr 11, 2006)

marty1 said:


> Just to check, by windows you mean the idt control panel?


No, I mean Windows as in the operating system, the one you get to by clicking Start, then Control Panel, then Sound (or type "sound" in the search box that is just above the Start button when you have clicked it and you will see "Sound" listed under Programs in the search results). It is the same one you have previously ended up in by looking at the USB audio device, but it is a panel that deals with all the audio interfaces Windows can see, which is why it lists the interfaces of the internal IDT soundcard as well as the USB card.


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## marty1 (Jun 29, 2010)

JohnM said:


> No, I mean Windows as in the operating system, the one you get to by clicking Start, then Control Panel, then Sound (or type "sound" in the search box that is just above the Start button when you have clicked it and you will see "Sound" listed under Programs in the search results). It is the same one you have previously ended up in by looking at the USB audio device, but it is a panel that deals with all the audio interfaces Windows can see, which is why it lists the interfaces of the internal IDT soundcard as well as the USB card.


Listen to this device was definately not ticked


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## JohnM (Apr 11, 2006)

Check that SRS Premium or any other effect is turned off in the IDT control panel, and that the equaliser settings are all exactly at zero or disabled - there may be a setting in the preferences to disable all effects. Some sort of effect or EQ appears to be active. If you can't find whatever is being applied, and a second measurement looks exactly the same as the first, you can go through the soundcard calibration process and calibrate away the uneven response, but it would be best to turn off whatever is causing it.


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## marty1 (Jun 29, 2010)

JohnM said:


> Check that SRS Premium or any other effect is turned off in the IDT control panel, and that the equaliser settings are all exactly at zero or disabled - there may be a setting in the preferences to disable all effects. Some sort of effect or EQ appears to be active. If you can't find whatever is being applied, and a second measurement looks exactly the same as the first, you can go through the soundcard calibration process and calibrate away the uneven response, but it would be best to turn off whatever is causing it.


I went into idt audio control playback section and srs premium was enabled, there was 2 circles to click, 1 for srs premium and 1 just below it that said headphones, I unclicked both circles (should I have left headphones on on srs premium screen?) and measured again:


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## JohnM (Apr 11, 2006)

Eureka! Perfect soundcard measurement, well done! :yay:


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## marty1 (Jun 29, 2010)

JohnM said:


> Eureka! Perfect soundcard measurement, well done! :yay:


YEEEEAAAAAHHHHH!! :rofl:

At last! Thanks for your help John (and Wayne), couldnt have done it without ya!

So should I scrap my soundcard or will that be worth using now that we know it was srs causing the problem?

Thanks Again
Marty


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## JohnM (Apr 11, 2006)

SRS is probably only a feature of your IDT card, nothing to do with the USB card, so there's still something odd with that. Doesn't mean it would not work just fine as a soundcard in general, particularly for playback, but not for acoustic measurements.


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## marty1 (Jun 29, 2010)

JohnM said:


> SRS is probably only a feature of your IDT card, nothing to do with the USB card, so there's still something odd with that. Doesn't mean it would not work just fine as a soundcard in general, particularly for playback, but not for acoustic measurements.


Ok thanks again John, I feel I have learnt quite a lot from this thread :T


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