[castleofargh]

well consider, from 0.5V to 1V it's +6db.  so I guess you can enjoy this "horribly wrong" value at 1khz without too much worries for most practical uses ^_^.

 

[CraftyClown]

  well consider, from 0.5V to 1V it's +6db.  so I guess you can enjoy this "horribly wrong" value at 1khz without too much worries for most practical uses ^_^.

 
Haha, I thought it was close enough, but I had to ask.
 
I'm afraid I still need you to help me take baby steps through this though as I'm not 100% sure of what else needs to be done.
 
So where I am right now;
 
1. My DAP is playing a 1khz tone through my IEMs.
 
2. I have removed the right hand monitor to reveal the 2 pins at the end of the cable
 
3. I am attaching the two prongs of the multimeter to the 2 pins on the cable and attenuating the volume until the meter reads approx 2v
 
4. Now what?  

 

[castleofargh]

0.2v !!! if you're going to use the values from the er4's measurement certificate. it's the only reason we pic this, it's the value Ety used, nothing more.
then you plug the er4, put it into the veritas set up whatever it is you think you need to set up and in REW you use the SPL meter for calibration. calibrate with external signal to use the test tone into the IEM(so that it measure 1khz only) and just enter 104db or 104.5db(whatever your certificate gives for that er4 driver fed 0.2V) and you're done.
now when you measure something, you can read how loud it's going directly on the measured graph.

 
 
it makes things way easier for measurements afterward to do them all at about the same loudness, make sure you're not killing your IEMs with 130db or simply to have meaningful values on the graph and calculate the actual sensitivity you're getting compared to specs(like Tyll does).

 

[bartzky]

   
Haha, I thought it was close enough, but I had to ask.
 
I'm afraid I still need you to help me take baby steps through this though as I'm not 100% sure of what else needs to be done.
 
So where I am right now;
 
1. My DAP is playing a 1khz tone through my IEMs.
 
2. I have removed the right hand monitor to reveal the 2 pins at the end of the cable
 
3. I am attaching the two prongs of the multimeter to the 2 pins on the cable and attenuating the volume until the meter reads approx 2v
 
4. Now what?  

 
Okay, I try to make it as easy as possible for you 

 
1. Don't take your DAP. It probably has high-z out. Take the 0.47 Ohm out of your Geekout.
 
2. Use a Y-splitter

 
3. Use one output of the Y-splitter for your ER4 and the other one for a cable like this:

 
4. Connect your multimeter to cable 3. from GND to left or from GND to right (doesn't matter).

 
5. Play the 1 kHz 0dBFS file in loop.
 
6. Adjust the volume to 0.2 V aka 200 mV and for god's sake do not feed your IEMs with 2 V!!!
 
7. Go on with what @castleofargh has written in post #78.

 

[CraftyClown]

  0.2v !!! if you're going to use the values from the er4's measurement certificate. it's the only reason we pic this, it's the value Ety used, nothing more.
then you plug the er4, put it into the veritas set up whatever it is you think you need to set up and in REW you use the SPL meter for calibration. calibrate with external signal to use the test tone into the IEM(so that it measure 1khz only) and just enter 104db or 104.5db(whatever your certificate gives for that er4 driver fed 0.2V) and you're done.
now when you measure something, you can read how loud it's going directly on the measured graph.

 
 
it makes things way easier for measurements afterward to do them all at about the same loudness, make sure you're not killing your IEMs with 130db or simply to have meaningful values on the graph and calculate the actual sensitivity you're getting compared to specs(like Tyll does).

 
 

   
Okay, I try to make it as easy as possible for you 

 
1. Don't take your DAP. It probably has high-z out. Take the 0.47 Ohm out of your Geekout.
 
2. Use a Y-splitter

 
3. Use one output of the Y-splitter for your ER4 and the other one for a cable like this:

 
4. Connect your multimeter to cable 3. from GND to left or from GND to right (doesn't matter).

 
5. Play the 1 kHz 0dBFS file in loop.
 
6. Adjust the volume to 0.2 V aka 200 mV and for god's sake do not feed your IEMs with 2 V!!!
 
7. Go on with what @castleofargh has written in post #78.

 
Brilliant, thanks guys 
 
If the output impedance on my DAP is low enough, ie less than 1 ohm, would it be ok to use?
 
also 2v was a typo 

 

[bartzky]

If the output impedance on my DAP is low enough, ie less than 1 ohm, would it be ok to use?

Should be okay then, but I really don't know how you would use a DAP with REW...

 

[CraftyClown]

Should be okay then, but I really don't know how you would use a DAP with REW...

 
I'm probably being a doofus here and missing something obvious, but why would it matter as long as the veritas is connected to the PC and is being recognised by REW?

 

[csglinux]

Should be okay then, but I really don't know how you would use a DAP with REW...

USB DAC mode??

BTW, those of you using REW, how have you been adding your diffuse-field corrections? Have you done this via the generic (file-based EQ)? I presume if you didn't care about the raw measurements, you could bundle all corrections into the soundcard calibration file, but I think I'd rather keep those unadulterated raw measurements. What's the best way you've found to produce both curves?

I've found my raw measurements quite close to those of Innerfidelity's, except beyond 10 kHz, where the Vibro Veritas mic seems less sensitive and shows a faster roll-off.

Ooh. One other thing I forgot to mention about my VV coupler. I also coated the inside of it with UV6800. The way it was printed, it had a sort of discontinuous seam or ridge running down the length of the inside of the coupler (in the axial direction). The texture of the UV6800 glue is a little rubbery and helps to get a consistent seal.

 

[csglinux]

I'm probably being a doofus here and missing something obvious, but why would it matter as long as the veritas is connected to the PC and is being recognised by REW?

I'm also being a doofus. My X7 seems to be working fine with REW. I didn't want to use my soundcard to also drive my headphones, because its output impedance is too high for some of my IEMs. My X7 seems to be working fine. I hope I'm not committing some terrible engineering error here!!

 

[bartzky]

USB DAC mode??

That's a valid point, but not every DAP can do this.

 

[CraftyClown]

That's a valid point, but not every DAP can do this.

 
I wasn't going to use it in USB DAC mode, but if I'm purely using it to test the SPL of my IEMs then why would I need to?

 

[bartzky]

I wasn't going to use it in USB DAC mode, but if I'm purely using it to test the SPL of my IEMs then why would I need to?

As soon as you need to use REW.

 

[csglinux]

@bartzky, have you ever used .req files with REW for EQ/correction? These are binary files, so I've having fun editing them Is there an easy way to make up and import parametric EQ files? 

 

[CraftyClown]

As soon as you need to use REW.

 
What am I missing here?
 
When I open REW and go to the SPL meter it is reporting back the SPL of my microphone input which in this case is my Veritas.
 
If the IEMs I want to check the desired listening level of are playing back a 1khz tone from my DAP, what would be the problem?
 
Once again I'm sure this is me being an idiot, but if you could explain I would be grateful  

 

[bartzky]

@bartzky
, have you ever used .req files with REW for EQ/correction? These are binary files, so I've having fun editing them Is there an easy way to make up and import parametric EQ files? 

I tried to use it.. I thought like "hey I have got two different IEMs - can one possibly make them sound the same?". I thought two sets of measurements and REW were the weapons of choice. Sadly I found it to be much to complicated so I ended up using the ADI-2 Pro's EQ.

If you ever find an easy way: please tell me