Lost my Notes :(

[Paul Canaris]

It,s been a few years since I generated a convolution filter (new speaker orientation in room) and I find I am not even sure I have the basic equipment hookup correct. Tell me if this will work. I am feeding my laptop (loaded with REW) with a UMIK-1 microphone (USB). From there it is a USB out to my Benchmark DAC3 input, with output of Benchmark going to amps to speakers. Am I correct that I do not need any other cables etc.?

 

[John Mulcahy]

Sounds fine.

 

[Paul Canaris]

Great...going to try it tomorrow. John is it OK if I post specific questions as I go along? Been watching Youtube videos but that has only gotten me more rather than less confussed. My goal is to have a filter to plug into my JRiver media player.

 

[John Mulcahy]

Sure, that's what the forum is for.

 

[Paul Canaris]

So here goes. For what it is worth my speakers are the GR Research LS9. As you can see they are a line source. The filter I want to generate for the JRiver player is to address the low end only to clear up bass modes. Unless I have been doing it entirely wrong in the past, my first attempts were to go as high as a few Khz but this resulted in the sound stage doing odd things; as in right and left images were uneffected but the center of the image seems like listening through a large diameter pipe of great depth. Oddly this effect also produced a great deal of additional clarity in terms of detail, but ends up being annoying over time. So I subsequently limited the filters to below a few hundred hertz. Right now I am looking at the Equalizer tab; target settings; and dont recall what I did in the past to set a filter range from 20 hz to around 120 hz. Can you assist?

 

[John Mulcahy]

The match range is on the Filter Tasks pane.

 

[Paul Canaris]

Got it. So I can ignore the Target Settings tab; i.e. values are meaningless?

 

[John Mulcahy]

They are not meaningless, they define what the target looks like. The match range defines the region within which REW will apply filters to try and bring the response onto the target. The EQ Window help explains what the various settings do.

 

[Paul Canaris]

I was able to generate filters. Not sure if I did the prefference settings correctly-optimally. Attached is a picture of what settings are. Confussed as not sure all of it apply to my basic setup. In particuar not sure how to set the Output Left Right channels or the Input L R channels.

 

[Paul Canaris]

PS my Laptop Audio is set to my Benchmark DAC. My DAC is a USB DAC so as far as I am aware, the laptop soundcard does not come into play.

 

[John Mulcahy]

The UMIK channel doesn't matter, it has the same data on both channels. For the DAC select the L channel when you want to play the test signal from the L speaker and the R channel to play from the R.

 

[Paul Canaris]

When I do the R- L flip on the speaker tab when measuring each channel, do I change the "timing reference Output" to match or go opposites?

 

[John Mulcahy]

No, to be useful as a reference it needs to stay on the same output.

 

[Paul Canaris]

Thanks

 

[Paul Canaris]

Great! I was able to generate filters that my Convoluter accepted. Sound is quite nice. But, while going through the stepsof creating the filters I get a message saying something to the effect that I was 77% above the target curve? What did I do wrong?

 

[John Mulcahy]

It means pretty much what it says, most of the response is above the target. That might mean your target level is a little low, or it might just be that the response has some big room resonances and the target level is OK.

 

[Paul Canaris]

Thanks for all the help. The results are very nice.