# Help with setting up and calbrating my soundcard....using an EMU 1820M



## Max Dread (Oct 20, 2010)

Hi all

I'm afraid I think I might have fallen at the first hurdle here and wondered if anyone can help pick me up!!!

I don't think my type of set up is covered in the help manual (or Cabling and Connection Basics file) - although it is quite (READ more than) possible I'm just being stupid and missing things! Here's details of my set up:

PC ---> EMU 1820M Soundcard with 8 channels of I/O --> Lavry DA10 DAC (connected via SPDIF) 

---> Event ASP8 Active monitors (connected via XLR)

I'm not sure at where I need to put in the loopback cable for S/C calibration. I tried it on Channel 1 (R) and just got a strange looking graph. I cannot use my "usual" output channel because that is SPDIF. 

So - what to do? 

I'm also not sure whether I should use balanced or unbalanced cables and if I should be using Right channel only or both?

I think this is likely to confuse me some more when it comes to main setting up and running measurements too..... When I ran a test before calibration, I plugged the mic into the built in pre-amp and left everything else as per the above diagram. But that means everything is running through both left and right. Should it be? 

Any help would be fantastic

Cheers

Max


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## EarlK (Jan 1, 2010)

Hi, 

- You mentioned you ran a sweep ( with the sound card uncalibrated ) . 
- Please post a screen-shot of that sweep .

*A few questions .*


"A" : What computer system ( plus OS ) are you using ?

 "B" : Have you actually seen proper input to REW on channel 1 ( left ) ?

 "C" : Do you see microphone input in the RTA window ?
- Open up the RTA window, ( press its' engage button ), then talk into your mic . The display should react to your voice .

 "D" : Can your soundcard sample at lower rates ( ie; 44.1K or 48K ) ? 

 "E" : Does REW output a clean 1K sine wave into your speakers ( or does it sound like a buzz saw ) ?
- Open up the Signal Generator icon and engage the 1K signal .




<> EarlK

BTW ; Once one has proper input signal ( as well as output signal ) , calibration is an actual snap .


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## Max Dread (Oct 20, 2010)

B*gger! I'm not sure I saved them sweeps, but I'll do some more and post the shots. Should I post All SPL or SPL and Phase?

A - Windows XP SP3. The PC is a self build Quad Core (Q6600) with 4gb RAM. Need any other specs?
B - That's part of my confusion to be honest. I've seen proper input but it is always on both channels (L and R). The Patchmix splits the mono mic input into left and right.
C - Yes, I do. The graph does react to my voice.
D - Yes it can. I'm using 44.1.
E - I opened it, chose Sine Wave and put in value 1,000. Is that correct? The sine was smooth....ish (maybe a touch of hiss but that could be resonance or something. I presume if like a buzz saw it would sound miles away from smooth???)

Thanks a million for the help

Max


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## EarlK (Jan 1, 2010)

> Should I post All SPL or SPL and Phase?


- SPL & Phase is fine / just don't display any Phase info .



> A - Windows XP SP3. The PC is a self build Quad Core (Q6600) with 4gb RAM. Need any other specs?
> _- Good to hear >>> fewer people have problems when using XP SP3 with their Sound Card of choice & REW ._
> 
> B - That's part of my confusion to be honest. I've seen proper input but it is always on both channels (L and R). The Patchmix splits the mono mic input into left and right.
> ...


<> EarlK


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## Max Dread (Oct 20, 2010)

OK - so all seems well aside from B! I'll experiment with the routing in Patchmix and see what I can get.....

As for the screenshots:

















I did one with phase because I wasn't sure if this is looking correct and so thought it was worth adding in here.

Thanks again for everything!

Max


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## EarlK (Jan 1, 2010)

Hi,


It's likely worth your while to read this blurb I found * on SOS(es) website about PatchMix .* 

The author offers some good advice .

A selective quote ;



SOS said:


> The new range of Emu soundcards (1820M, 1820, 1212M, 0404, and by the time you read this the 1616M as well) has been selling like hot cakes, *but many PC musicians find various aspects of their associated Patchmix DSP utility difficult to comprehend. It's not that the mixer is difficult to use; more that it offers so many possible options that it can be difficult for the newcomer to perform even basic tasks.*


Statements like this is why I suspect PatchMix is the source of the problem ( ie; doubled inputs / as well as, maybe a feedback loop to the output ) .

Let me know what you think .

Are you a PatchMix whiz ? ( or a newb ??? )

<> EarlK


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## Max Dread (Oct 20, 2010)

Perhaps I should clarify how things were set up for the above graph...

My mic was plugged into Mic1 Channel on the EMU. In Patchmix, I have the Mic1 Channel muted so that it is not heard through the speakers at the same time as the sweep (otherwise it would be measuring itself - I guess - at the same time as measuring the actual test tone!). BEFORE the mute switch on that channel strip, I have a SEND (called "WAVE L/R - HOST") - this sends whatever the mic receives to REW. 

I then have another channel strip - WAVE 1/2 - which is what REW plays its tones and signals through. 

The Main Outputs are then sent to the SPDIF Out, which is connected to the Lavry, which is connected to the powered monitors....

Don't know if that clears or clouds things up!?!

But based on that, I've still no idea where to plug in and out to create the loop because my input is a mic input (I presume I need line level) and the output I'm using is an SPDIF. When I tried to do the cal. I simply plugged a lead into Channel 1 IN (R) and Channel 1 OUT (R). These are not the same channel as the Mic CHannel 1 BTW.

Sorry for all this and thanks for the help again! I seriously owe you one!


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## Max Dread (Oct 20, 2010)

Oops - are posts crossed there, so I had not seen yours when I posted mine. And you had no doubt not read mine either!

I'm not a newb, but I do agree that there are so many options it can become confusing. In recording scenarios I can work my way around the patchmix fine. But using it with REW - as I'm sure you are finding out your self by reading my posts - is giving me a real headache!!! 

I'm fine for the actual measuremetns now and all is routed properly I think. Just the calibration I cannot figure....


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## EarlK (Jan 1, 2010)

*Re: Help with setting up and calibrating my soundcard....using an EMU 1820M*

Hi !

The whole idea behind creating a meaningful calibration file ( of the Sound Card & Associated electronics ) is so that this calibration file cancels out any inherent inaccuracies found within your _( personalized )_ * Recording/Playback chain *.
- ie; Change anything in that chain of electronics & you need a different calibration file ( technically ) .

*Therefore, with that in mind ; *

- Take the analog output ( found, after your DAW / just before your speakers ) and plug it into the same preamp that you are currently using for your test mic ( turn off the Phantom Power first ) . 

- You should be able to simply adjust the EMUs input gain downwards to accommodate the line level feeding into a mic preamp ( I do this with my M-Audio FastTrack Ultra, with no problems when I calibrate it ). 

- And get rid of that aux routing ( & whatever else you mentioned ) which you are currently using as a tap/feed to jury-rig together a "loopback" .

- Remember, don't route this input to the output ( however you want to snuff out that send is up to you ) .
- Just don't create a feedback loop .

- And make sure that you route REWS output into PatchMix(s) main outputs .



Now Try a Calibration ( after first checking levels ) !

<> EarlK


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## Max Dread (Oct 20, 2010)

Still not having no joy.....not directly anyhow!

Indirectly I came across this post just now:

http://www.hometheatershack.com/forums/rew-forum/38018-step-4-soundcard-calibration.html

Seems there is less than 0.5db variation from 20 - 20000hz on the EMU 1820M. So, am I right in saying that the ONLY downside to not using a calibration file for soundcard is an inaccuracy of well under 1db? If so, perhaps I'll just skip this as my result do not need to be THAT accurate. 

OTOH, I've bumped the thread I linked to to see if the OP has any suggestions or a walk through on what he did....

That's not taking away anything from how much I appreciate your help and support!


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## alex_t (Feb 9, 2007)

Hello.

I would like to help you but can you explain what is your problem with simple words because I'm french and my english is not very good.

First you can download the same session that I used : http://www.emu.com/support/files/download2.asp?Centric=759&Platform=1 (bottom)

Cables needed :

- TRS 1/4 mono to RCA : emu's output to my audio processor
- TRS 1/4 mon to RCA + RCA/XLR adapter to perform the card calibration
- a MIC with its external phantom power (XLR to XLR)


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## Max Dread (Oct 20, 2010)

Thanks Alex! I really appreciate it....

I only really have one problem now, and that is *probably* with how to set up and route the patchmix to calibrate the sound card. 

I have done as EarlK suggested, and linked up the Right output from my Lavry DAC (Digital to Analogue Converter) to the Mic A (1) input of the EMU. But I still cannot get a calibration file to work. I think it is to do with something in the patchmix that I have/haven't done.

Cheers mate

Max


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## EarlK (Jan 1, 2010)

Max,

*NO JOY !*
Yes, you could run without a SoundCard calibration file / & it wouldn't be the end of the world .

But ( really ) just what is happening ( or not ) when you run the SC calibration routine ?
- Could you post a screen shot of the result ?

*
More Screen Shots Please !*
(i) Can you post a screen shot of your choices within REW Preferences ?

(ii) Also please post a screen shot of your XP Sound Control Panel choices ?


*SOMETHING to TRY :*
(i) Unplug all your EMU gear from your computer.

(ii) Open up REW .

(iii) In the Preferences window > choose ( under input ) the computers builtin SoundCard as the Audio Device .

(iv) Then choose "Line In" if it is available as a choice .

(v) Output can be "Speaker"

(vi) Run a Calibration Routine .

(vii) You should not get any input registering in these circumstances

*NO "Line In" as an available input choice ??*

(i) to (iii) Same as above 

(iv) Choose " Stereo Mix ( Stereo Mix ) " as the routed input .

(v) Output can be "Speaker"

(vi) Run the Calibration Routine .

(vii) If you have input registering under these circumstances, it means your XP ( like mine ) *internally routes output to input* when "Stereo Mix" is choosen . 
- Here's a pic of mine ( this is with no external sound card and *no looping cable* ) . 









(viii ) Instead ; Choose Mic input in this selection box ( & then back off it's input gain ) .

(ix) Try another Calibration Routine ( again, with no Emu Sound Card ) . If you have *no input registering *( you are "good to go" / then, Shut-down the computer / Reconnect you Emu stuff / Reboot / Open up REW / Select the Emu card within the REW preferences / Select "Line Input" ( if it's a choice ) or alternately, "Mic input" / ( just don't select "Stereo Mix" ) . 

(x) Run another Calibration Routine ( *without* the loop-back cable in place ) to make sure you don't see any input .

(xi) ( then ) Run another Calibration Routine ( *with* the loop-back cable in place ) looking to see input only registering on the REW channel being fed signal through your PatchMix routing.


And ???

<> EarlK


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## Max Dread (Oct 20, 2010)

Hi

Here are those shots...:

























When I have a few moments I'll run through the test with the onboard s/c. It will take a little monkeying about because it is currently disabled in BIOS, etc. But as soon as I get a mo..

Huge thanks

Max


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## alex_t (Feb 9, 2007)

Max Dread said:


> Thanks Alex! I really appreciate it....
> 
> I only really have one problem now, and that is *probably* with how to set up and route the patchmix to calibrate the sound card.
> 
> ...



I had the same problem. It was due to the MIC LEVEL, turn it at the minimum and try again.


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## EarlK (Jan 1, 2010)

*Re: Help with setting up and calibrating my soundcard....using an EMU 1820M*

Max

- To see if you've inadvertently setup an internal feedback path ( within PatchMix ) step through this simple routine ;

 Unplug your test mic .
 Unplug the output of your DAC that goes to your speakers.
 Open up REW
 Within the Preferences Window, run 2/3s of the way through the Calibration routine ( cancel before hitting the "calibrate" button .
 *No input *should register on REWs input meters if all your setup is proper . Like this ;









 If you do see metering ( input ) , you've got a feedback loop . 
Under these very specific circumstances, *you don't want to see *something like the following ;
- This is a shot of my own internal feedback loop ( using the internal soundcard, my settings are visible & with *no* connecting cables feeding output to input )











<> cheers


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## EarlK (Jan 1, 2010)

Max,

When you get the time, check out this YouTube Video . It might be of some help .







It's possible that the glitch he's talking about might also be effecting your system ( you mentioned 4 Gig of RAM / though the author is focused on OS, Vista-Win7 ) .











<> EarlK

ps ;  *Here's*  an older thread on "successfully" Calibrating the 1820M . A bonus is that is comes with a SCard calibration file, plus PatchMix "Session" , both zipped together for download .


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## Max Dread (Oct 20, 2010)

Hi

I'm back!

OK, RE: Post on 31st March, 2011, 14:50. 

I've tried as you suggested and everything is as it should be. With the mic and the outputs to the speakers all unplugged, I get nothing on the REW Input Meters when I go 2/3's of the way through the calibration. 

I also checked out the youtube video. Very interesting and not something I was aware of. But I don't think it is related to the problem because I have recorded many a time to a WAVE L/R Host and had no such problem.

I've just done a quick 20 - 20000 sweep (using both speakers) and here is the graph:









And I've also attached the file in case anyone needs to look at different aspects of the graph:

(see below)

Please let me know if I need to measure in any other way or do anything else to help. I'm not worried about the graphs dips and peaks from a sound point of view - I just want to know if it looks like a reasonably "Normal" sweep, or whether it looks like the soundcard issue (if there is one) is mucking things up.

Cheers
Max


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## Max Dread (Oct 20, 2010)

Hmmm... cannot get the mdat file to upload for some reason. Let me know if it is needed and I'll look into why I cannot upload it.

Many thanks

Max


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## EarlK (Jan 1, 2010)

Max,

- Yes that sweep looks quite normal .

- In the future, please post your graphs with some smoothing applied to the traces ( 1/6 to 1/12 octave is a good place to start ) .

>< EarlK


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## Max Dread (Oct 20, 2010)

Thanks for the quick reply Earl.....

Sorry about the lack of smoothing. Now that I have applied it I can see why it was needed!!!! It's all a steep learning curve but I'm really enjoying it and it is being made so much easier by guys like yourselves on forums helping me out.

Here's the graph with 1/12 smoothing:









So just to emphasise and confirm the point - the s/c issue does not look like it is interfering and I can now go ahead and start making measurements?


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## EarlK (Jan 1, 2010)

MAX said:


> So just to emphasise and confirm the point - the s/c issue does not look like it is interfering and I can now go ahead and start making measurements?



Well, you know what they say about "*Famous Last Words*" >>> but >>> 

"It looks to me like the soundcard issue is a non-starter here,,,so you're good to go" ( measure away ) .

BTW, if you ever get the issue resolved, please log on & let the rest of the world know the "secret sauce" to success ( so to speak ).

regards <> EarlK


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## Max Dread (Oct 20, 2010)

Dun dudun Dun Deerrrrrrrrrrrr!

Funny how things work out sometimes!

So I decided I did not need to calibrate my soundcard. Then I found I might have an issue with the soundcard which could obscure the results of measurements. So after some fantastic help from you in particular (and others too) I get through the problems and get the green light to take the measurements. 

But I had to give the soundcard cal. one last try didn't I? Hate to be defeated and all!

And guess what.....?









To be honest, I've tried so many different configurations with both the hardware and the patchmix routing that I'm unsure why this has happened now when every other time I got poop. But it HAS happened! 

So here's how things were set up when I got that graph...:

EMU and Lavry DA10 connected via SPDIF.

Lavry Output (R) XLR connected to the EMU 1820M Mic A using a TRS (not XLR). 

Nothing in the Lavry Output (L) channel.

Nothing else connected to the EMU. 

The Mic Pre Gain on the EMU was set so that the REW Input matched the REW Output (during the calibration process. This gave a setting on the pre of between two and three o clock.

Patchmix was set up like this:









The Send in the Mic Channel was sending to: WAVE L/R - HOST.

My REW preferences were set up like this:









On the next page, mic calibration was switched off/cleared.


I think that covers everything for anyone else who _might_ have trouble in the future!

Thanks again to everyone for the help and sorry if it was all due to an (unknown) oversight on my part!

Max


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## Max Dread (Oct 20, 2010)

Hi

Just a quick add here (because I've returned to REW today to learn more and take new measurements and have therefore been reminding myself of older posts)....

I was comparing my soundcard cal file graph (see above) with alex_t's:









I noticed that although they look similar, the actual bass roll off on mine - from 3hz to c100hz goes from -0.5dB to 0dB (well, just below - but as good as). On Alex's, the same frequencies go from -5dB to 0dB.

I know that such low frequencies are immaterial and can be ignored. But curiosity got the better of me and I wondered what the reason for this might be?

Cheers

Max


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