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Discussion Starter #1
I have used REW over many years, but not for the last 6-8 years.
I want to re-calibrate my sub (four x 15" in an infinite baffle).
I have downloaded the latest REW, but am using old equipment - EMM6 mic into a XENYX803 pre-amp, and then into a Sound Blaster Creative Digital Music LX connected to a USB input on my Windows10 laptop.

I can calibrate the soundcard, but when I try the next step - Checking Levels - I can't seem to get the Input levels up anywhere near to minimum levels i.e. above -18dB.
And the light on top of the Creative sound card continually flashes.:surprise:
I've checked all the settings countless times, including Creative's Windows 10 drivers for my soundcard.
I never had this problem previously.

I'm wondering if my soundcard is faulty.
Or perhaps I should be using an older version of REW.

Any help would be greatly appreciated.:smile:
 

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Have you selected the correct input channel in REW, i.e. the one your mic is plugged into? The input level with a speaker cal signal playing at 75 dB or thereabouts will depend on your mic input gain, it may not get above -30 or -40 dBFS even at the maximum input gain, but that isn't a problem.
 

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Discussion Starter #3
Have you selected the correct input channel in REW, i.e. the one your mic is plugged into? The input level with a speaker cal signal playing at 75 dB or thereabouts will depend on your mic input gain, it may not get above -30 or -40 dBFS even at the maximum input gain, but that isn't a problem.
Thanks John for your quick reply. :smile:
In REW both input and output devices are correctly set as the right channel of the external sound card (as recommended in your original tutorial). The Mic preamp and the power amp are both connected to the right channels of the sound card. The card was recognised by REW and I had no problems in calibrating the card.

Perhaps over time the Mic (EMM6) has lost its sensitivity. However in the preamp, if I turn the master volume up, I can induce some clipping.
Note that when I do that, the input level in REW doesn't move (stays around -45dB). BTW, this is with the input volume in REW at the maximum of 1.00.

I had no problems when I used this same set up several years ago, the only different I think, is that I was using Windows 7 and an older version of REW.

I did try a initial measure of the sub, but I received a message saying that my signal was to low. The SPL did not appear on the graph, although the phase had been plotted but actually looked like a SPL plot.

I thought I had solved the problem when I found some Windows 10 drivers for the sound card off the Sound Blaster site, but they didn't make any difference.
 

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However in the preamp, if I turn the master volume up, I can induce some clipping.
Note that when I do that, the input level in REW doesn't move (stays around -45dB). BTW, this is with the input volume in REW at the maximum of 1.00.
This would suggest that the mic preamp output is not feeding the selected REW input, otherwise the level would change. Maybe that is some issue with the Xenyx setup or perhaps the input that is selected on the Creative card isn't the one you have the Xenyx connected to, but it is pretty fundamental. If the computer has built-in line in and headphone out you could use those and remove the Creative from the equation.

As an aside, if (after sorting out the connectivity) you need more gain from the mic you should change the gain on the mic strip rather than the master volume, which is likely best left at the '0' gain setting.
 

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Does the Creative soundcard work otherwise? The reason I ask is because when you increased the XENYX volume, nothing changed in REW. That doesn’t sound right at all. Perhaps the Creative’s Windows 10 drivers aren’t cutting it.

In any event, assuming your EMM6 is calibrated, you might want upgrade to a USB interface (that does what the XENYX and Soundblaster does in a single box). Some of these can be pretty complex and expensive, but fortunately for REW the simplest devices work the best. Current models that should work fine are the Focusrite Scarlett 2i2 and PreSonus Studio 24c or AudioBox iTwo. Older models like the TASCAM US-222 and M-Audio Moble Pre also work well and can be found pretty cheap on ebay. Just make sure any of the older ones can get Windows 10 drivers

Regards,
Wayne
 

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Discussion Starter #6
This would suggest that the mic preamp output is not feeding the selected REW input, otherwise the level would change. Maybe that is some issue with the Xenyx setup or perhaps the input that is selected on the Creative card isn't the one you have the Xenyx connected to, but it is pretty fundamental. If the computer has built-in line in and headphone out you could use those and remove the Creative from the equation.

As an aside, if (after sorting out the connectivity) you need more gain from the mic you should change the gain on the mic strip rather than the master volume, which is likely best left at the '0' gain setting.
Thanks again John.
Checking the laptop (Dell Inspiron 15 5000) it does have a small single mic/headphone jack. I'll see if I can get a single all-in-one lead that will do the job.
Meanwhile I'm making a dedicated lead from the pre-amp to the sound card without the adaptors, etc I have in the line at the moment.

Because I can get the level lights to peak on the Xenyx, I believe the problem is between the Xenyx and the laptop.
Not sure what you mean by changing the gain on the Mic strip.
 

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Discussion Starter #7
Does the Creative soundcard work otherwise? The reason I ask is because when you increased the XENYX volume, nothing changed in REW. That doesn’t sound right at all. Perhaps the Creative’s Windows 10 drivers aren’t cutting it.

In any event, assuming your EMM6 is calibrated, you might want upgrade to a USB interface (that does what the XENYX and Soundblaster does in a single box). Some of these can be pretty complex and expensive, but fortunately for REW the simplest devices work the best. Current models that should work fine are the Focusrite Scarlett 2i2 and PreSonus Studio 24c or AudioBox iTwo. Older models like the TASCAM US-222 and M-Audio Moble Pre also work well and can be found pretty cheap on ebay. Just make sure any of the older ones can get Windows 10 drivers

Regards,
Wayne
Thank Wayne.
I bought the EMM6 calibrated through HTS.:smile:
I keep worrying that the creative box is my problem. My problem existed even before I realised I didn't have any Windows 10 drivers.
I'm going to try the ideas I posted to John, but if that fails, then I'll start looking at the USB preamps you have recommended.
(wish I had some mates with similar interests and equipment):crying2:
 

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Not sure what you mean by changing the gain on the Mic strip.
Top of the channel strip, the black knob below the input jacks. It adjusts the level of the input device. If it’s too low, you have to turn the “downstream” level controls up high to compensate. If it’s too high you get clipping even with the downstream level controls set very low.

What you can do is firmly tap on the head of the mic and increase the gain knob until the clip LED beside the Pan knob lights, then back it down a bit.

Regards,
Wayne
 

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Discussion Starter #9
Top of the channel strip, the black knob below the input jacks. It adjusts the level of the input device. If it’s too low, you have to turn the “downstream” level controls up high to compensate. If it’s too high you get clipping even with the downstream level controls set very low.

What you can do is firmly tap on the head of the mic and increase the gain knob until the clip LED beside the Pan knob lights, then back it down a bit.

Regards,
Wayne
Aha!
While Checking Levels I did have a fiddle with this knob while watching the level bar in REW, but didn't appear to make any difference.
I'll try your method. :T
 

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Discussion Starter #11
I found a small adapter plug for the mic/headphone socket on my laptop.
Connected the DSP1124P/amp directly to the laptop, as well as the output of the Xenyx.
Check Levels looked quite good, but when I ran a Measure, the onboard sound is useless - dived from 100Hz down to zero at 60Hz.
Last resort will be a better cable from the Xeynx to the Creative box, before I start looking for a USB pre-amp and/or sound card.
 

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Discussion Starter #12
To John and Wayne
You two are absolute legends, and I feel so embarrassed wasting your time.:crying2:

Was digging around amongst all my cables, adapters, etc. and I found the cable I had always used between the Xenyx and the sound card - 1/4" mono jack one end, and a gold RCA at the other.
When I pulled out the one I was using, I suddenly realised that the 1/4" jack was a stereo jack.
Hooked up the proper cable, and voila - everything works perfectly.:grin2:

Thanks so much for your patience.
 
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