# REW EQ Filters For Antimode Dual Core 2.0?



## Phillips (Aug 12, 2011)

Hi John is there any possibility that you could load this into REW.

It uses Bandwidth.

Center Frequency divided by Q = Bandwidth (entry for Antimode).

e.g 500hz Q 4 Bandwidth 125 

Thanks in advance


----------



## JohnM (Apr 11, 2006)

The manual isn't very specific about what the 'bandwidth' refers to, beyond saying 'approximately the 3dB bandwidth'. Would need loopback measurements for a range of filter gains and bandwidths to try and understand what definitions they have used, but I'm not sure the time would be well spent - most people buy the Antimode for its automatic EQ features, not to manually adjust it.


----------



## Phillips (Aug 12, 2011)

JohnM said:


> The manual isn't very specific about what the 'bandwidth' refers to, beyond saying 'approximately the 3dB bandwidth'. Would need loopback measurements for a range of filter gains and bandwidths to try and understand what definitions they have used, but I'm not sure the time would be well spent - most people buy the Antimode for its automatic EQ features, not to manually adjust it.



Thanks John 

I can contact them to see if the info is available, please list the details you need specifically and i will contact them. Please let me help with anything that will make it easier for you.

The bandwidth is Centre Frequency divided by Q = BW if that helps? Not sure of the frequency range increments though.

Yes for the bass region the Auto works very well, but above that the manual EQ is versitile.

Thanks again


----------



## Phillips (Aug 12, 2011)

Hi John i believe the definitions are, center frequency is in Hz, and the BW is roughly about ~3dB (50% power band) of the effect.

Is there any more info you need?


----------



## morca (Aug 26, 2011)

I Think it could be adding to the dualcore.
At the dutch forum i am a member,i know 3 dualcore,s in use.all 3 users prefeer after the autosetting manual adjusting and use REW to do it.


----------



## JohnM (Apr 11, 2006)

Phillips said:


> Is there any more info you need?


Loopback measurements of filters (with the filter settings recorded in the measurement notes) at a few different settings, e.g. 1kHz centre, -6dB gain and various bandwidths then the same for -12dB gain, along with info about how many filters the unit supports, gain range and resolution, frequency range and resolution and bandwidth range and resolution.


----------



## Phillips (Aug 12, 2011)

JohnM said:


> Loopback measurements of filters (with the filter settings recorded in the measurement notes) at a few different settings, e.g. 1kHz centre, -6dB gain and various bandwidths then the same for -12dB gain, along with info about how many filters the unit supports, gain range and resolution, frequency range and resolution and bandwidth range and resolution.


Thanks John

Can i do this with a USB mic?


----------



## Phillips (Aug 12, 2011)

morca said:


> I Think it could be adding to the dualcore.
> At the dutch forum i am a member,i know 3 dualcore,s in use.all 3 users prefeer after the autosetting manual adjusting and use REW to do it.


Thank you

How do you/other forum members run the Dual Core?


----------



## JohnM (Apr 11, 2006)

Phillips said:


> Can i do this with a USB mic?


No, it needs to be a measurement of soundcard output -> dual core -> soundcard input, a loopback with the dual core inserted in the loop.


----------



## Phillips (Aug 12, 2011)

morca said:


> I Think it could be adding to the dualcore.
> At the dutch forum i am a member,i know 3 dualcore,s in use.all 3 users prefeer after the autosetting manual adjusting and use REW to do it.



Is it possible yourself or other forum members could do the loop back (post 6 & 9) measurements for John?


----------



## Phillips (Aug 12, 2011)

Hi John is there anything else i can do to help, i have a USB mic?


----------



## morca (Aug 26, 2011)

I do not own one myself,butt a member i know very well own,s one.
I am gonna send him this topic link .
I hope he has time and want,s to do it.


----------



## staaled (Sep 9, 2010)

I own two DC's as Morca stated, kinsman.

Import the frequency to your PC or Mac via the PC link option ( see manual)

Then choose import frequency response in REW without applying C weighting.
Response should show ( before or after graph).

Then adjust to preference. Exporting is not possible so adjust on the dualcore according to REW filter settings.

Hope this helps.


----------



## morca (Aug 26, 2011)

My mistake again,twice ......
This is the second time i forgot you own 2 of them :bigsmile:


----------



## Phillips (Aug 12, 2011)

Thank you all.

John needs the loop back so he can load the filter settings into REW, so REW matches the Dual Cores PEQ filters and BW etc.

Thanks again


----------



## Powerdubs (Mar 20, 2016)

I have an Antimode dual core and would also like to be able to have REW generate PEQ settings for it, to fine tune the results.

The dual core-

Allows 16 PEQ slots 

Gain is -36DB to +12DB .. the gain db does have decimals in the 10nth spot +/-.1 .2 .3 etc.

Freq range is in solid numbers, not decimals, from 5hz to 20k

As already mentioned, it does not use Q, it has bandwidth, which I guess is the range to each side of the chosen freq? It is solid #'s from 1 to 10k


----------



## Phillips (Aug 12, 2011)

Could use the Generic or Mindsp EQ filter and the BW quantity and then fine tune or use the RTA

You will probably find that there is isn't enough people using this to have a Dual Core EQ in REW


----------



## Powerdubs (Mar 20, 2016)

That is disappointing, as is the lack of response from John. The Antimode is fairly popular, and I wouldn't think it would be that hard to integrate. I would happily contribute funds to the work.


----------



## Phillips (Aug 12, 2011)

The problem being not many people have posted here.

Can you measure the AM filters via loopback?
This would help John determine


----------



## Kal Rubinson (Aug 3, 2006)

Powerdubs said:


> That is disappointing, as is the lack of response from John. The Antimode is fairly popular, and I wouldn't think it would be that hard to integrate. I would happily contribute funds to the work.


I don't know how many of us use the AM2 or what the wider market is but I, for one, would like to be able to better use my AM2.


----------



## JohnM (Apr 11, 2006)

Back in the second post of this thread, nearly 3 years ago now, I asked for loopback measurements so I could support this. There haven't been any, which I presume is either a reflection of the level of interest or because users have found one of the existing EQ emulations meets their needs.


----------



## Kal Rubinson (Aug 3, 2006)

JohnM said:


> Back in the second post of this thread, nearly 3 years ago now, I asked for loopback measurements so I could support this. There haven't been any, which I presume is either a reflection of the level of interest or because users have found one of the existing EQ emulations meets their needs.


Or is it not possible or convenient to do this at this time. I am expecting some new subs and will be installing the AM2 with them. I can do the loopback measurements then but that will be in late April (when I get back from Brussels).


----------



## Powerdubs (Mar 20, 2016)

And now you have 3 current users in the past few days who want the feature. I am sure we can spread the word once the feature exists as well.

I have given you everything you asked for besides the loopback because I do not know exactly what it is that you want there- remember, not all of us are as knowledgeable as you- we may need to be walked through the steps a little more specifically.

I get the loop- computer to dual core back to computer. Now what?

Besides spreading the word, I'd also imagine at the very least all three of us can throw a few bucks your way for beer as well. 

BTW- I tried the existing option from the drop down and they did not work.


----------



## JohnM (Apr 11, 2006)

See post #6.


----------



## Powerdubs (Mar 20, 2016)

I've seen post six. 

You must have missed post #23- where I said "remember, not all of us are as knowledgeable as you- we may need to be walked through the steps a little more specifically."


----------



## JohnM (Apr 11, 2006)

There isn't much to explain, it really is just making measurements as requested. Make one with no filters set up to make sure the result is flat (as would be expected), then set up a filter at 1 kHz with -6 dB gain and bandwidth of (say) 100 Hz, make a measurement, change the bandwidth to 200 Hz, make a measurement, change the bandwidth to 500 Hz, make a measurement, change the gain to -12 dB and make measurements with the same 3 bandwidths. Use Save All to save the measurements and post the mdat here.


----------



## ajinfla (May 10, 2009)

Powerdubs said:


> I've seen post six.
> 
> You must have missed post #23- where I said "remember, not all of us are as knowledgeable as you- we may need to be walked through the steps a little more specifically."


Powerdubs, please be a bit more respectful in the tone of your posts. John is volunteering his time here, the software is free. Friendly advice this time. Thanks.


----------



## pre (Aug 20, 2013)

Planned REW loopback connection with 
USB soundcard UCA222 and AM2.0.

loop.... rca wire is connected from UCA222 line output R to AM2 line in R
and then the ...back wire rca is connected from AM2 line out R back
to uca222 line in R. See picture below for connector panels.

please advice if above is what is requested for the measurements in next post #29 ?

Later for measuring in general with rew the toslink output from uca222 is practical for longer distance fibre link from PC to dac or other toslink input device like AM2.0. Note that then loopback correction is then not valid because uca222 does not have digital toslink input for making the loopback correction.


----------



## pre (Aug 20, 2013)

Is this what is expected as post #6 way of measurements. In case something understood wrong, please advice what needs to be changed below.

Preparations
- must be a measurement of soundcard output -> dual core -> back to soundcard input, a loopback where the dual core is inserted in the measurement loop. No mic measurement. see previous post.

Make first one clean REW frequency sweep measurement 
- with not any AM2.0 filters or corrections set to make a flat clean non corrected measurement. 

Make then following extra measurements 
- document each filter setting values into each measurement notes window
- set up a filter at 1 kHz 
* -6 dB gain and bandwidth of 100 Hz
* make the measurement 

- keep the filter at 1kHz 
* change the bandwidth to 200 Hz
* -6dB gain 
* make next measurement

- keep the filter at 1kHz 
* change the bandwidth to 500 Hz
* -6dB gain 
* make next measurement

- keep the filter at 1kHz 
* change the bandwidth to 100 Hz
* -12dB gain 
* make next measurement

- keep the filter at 1kHz 
* change the bandwidth to 200 Hz
* -12dB gain 
* make next measurement

- keep the filter at 1kHz 
* change the bandwidth to 500 Hz
* -12dB gain 
* make next measurement

Use REW "Save All measurements" from REW menu to save all the different measurements and post the mdat file here.


----------



## Powerdubs (Mar 20, 2016)

pre said:


> example of REW loopback connection with
> USB soundcard UCA222 and AM2.0.



Pre, thank you for that information. Over the weekend I had tried hooking to the input on my laptop to get these test results with no luck. I had the same problem originally when I tried to plug in to the mic jack for rew scans which is why I ended up buying a usb mic. My laptop doesn't seem to like it's normal mic plug input.

Now that I know this simple box exists to allow me to interface, I will order it today. Hopefully I will be able to get this loopback info in a few days time.


----------



## Phillips (Aug 12, 2011)

John would it be possible to load into the AM2 automatically as manually entering into the very small screen was a pain?

Thanks in advance


----------



## JohnM (Apr 11, 2006)

Hi Pre, the setup as described is correct. Begin by making a loopback measurement of the soundcard alone to make sure all is well there before putting the AM in the loop. Make sure Monitor is off. 

Phillips, depends what protocol the AM uses and whether they publish it. REW under Windows can send messages over Midi or RS232.


----------



## Powerdubs (Mar 20, 2016)

Hi guys,

The interface box mentioned above arrived today, and I tried my best to make it work. Unfortunately I failed. 



I was hoping it would by much like my Umik, and the Dual core itself that it would be pretty much plug and play and user friendly.

No matter what I tried, I couldn't get it to work. 

I plugged the USB from the box into the laptop- rca output to dual core, rca out from dual core back to rca input on box. 

In REW preferences, picked USB for in & out.

Click scan and it gives an error about level. Click OK.. scan runs but graph starts high and descends to low, and gets fuzzy towards the end.

Tried to adjust PEQ- no change

SO go back to flat, try a new base scan and when it gives level error, adjust the DB level to match, then scan...no change in behavior.

Well, sorry guys, I spent my own money to try to get the data needed, but I am not knowledgeable enough to navigate the software settings and make it work. 

Any advice is appreciated. I am here to help get this done- but this is not my expertise.


----------



## JohnM (Apr 11, 2006)

Might be the channel you had selected in the REW Soundcard Preferences for REW to listen to isn't the one that you had the loopback connections on. Still recommend just making a loopback measurement of the soundcard itself to start with. If you are unsure of the settings post a screenshot of the REW Soundcard Preferences for us to check over.


----------



## Powerdubs (Mar 20, 2016)

pre said:


> Make first one clean REW frequency sweep measurement
> 
> - set up a filter at 1 kHz * -6 dB gain and bandwidth of 100 Hz
> 
> ...



Done. Files attached.


----------



## JohnM (Apr 11, 2006)

Great, thanks. Bit of an odd artefact in the impulse responses when going through the AM, but the measurements have the info needed in any case. The filters use a -3 dB bandwidth definition which introduces a sqrt(gain) factor (like the USM-810). I'll see if I can add an implementation to the next V5.15 beta release.


----------



## Powerdubs (Mar 20, 2016)

Thanks John.

For all I know, the anomaly could be something I did. This is all greek to me.

If it helps get this feature added sooner rather than later, I can certainly donate some funds. I'm excited to play with the adjustments. 

For reference on the other stuff you asked for again-

The dual core-

Allows 16 PEQ slots

Gain is -36DB to +12DB .. the gain db does have decimals in the 10nth spot +/-.1 .2 .3 etc.

Freq range is in solid numbers, not decimals, from 5hz to 20k..which is good because my subs are into single digit hz in my room.

Bandwidth is solid #'s from 1 to 10k


----------



## JohnM (Apr 11, 2006)

V5.15 beta 6 is now in the usual place. 

Changes in beta 6:

Added a left/right output channel selector in the Soundcard preferences when using Java drivers, meas sweep only appears on selected channel unless using loopback, when it appears on both
When using acoustic timing reference can now also measure the timing ref channel
Added an equaliser setting for the Anti-Mode 2.0 Dual Core


----------



## lizrussspike (Aug 18, 2014)

Powerdubs said:


> Hi guys,
> 
> The interface box mentioned above arrived today, and I tried my best to make it work. Unfortunately I failed.
> 
> ...


 @Powerdubs 
Power,
Did you get this to work with the AM2DC?


----------



## Phillips (Aug 12, 2011)

Hi I gave the EQ a try and worked great but as the frequency gets higher, the increments change.


----------



## Thomu (Apr 13, 2016)

I just registered to say thank you for adding the Antimode Dual Core-EQ-setting! I tried it today and it worked perfectly with the settings i got from REW. I used it from 30 to 500 hz because i wasn´t satisfied with the automatic corrections of the Anti-Mode and didn´t try higher frequencies. Just a small suggestion: Maybe the term "Anti-Mode 2.0" would be more self-explanatory instead of "Dual Core" - at least for owners of the device?


----------



## Phillips (Aug 12, 2011)

Matter of interest did you EQ left and right separate or together?


----------



## Thomu (Apr 13, 2016)

Together, because most of the corrections were between 30 and 130 Hz.


----------



## FargateOne (Mar 3, 2015)

Big thanks to John.:hail:
I had Antimode 2.0 and used Rew to try to fine tuned his filters. I sold it because it was for me very difficult. If I had been able to predict the future I would have wait for you.
I am sure that many AM 2.0 will be very happy.
Thank on behalf of those more persevering than me !.


----------



## Phillips (Aug 12, 2011)

Thomu said:


> Together, because most of the corrections were between 30 and 130 Hz.


Interesting cause I thought that I saw a thread saying the Eq should be done independently for bass up to about 300hz (each case can be different) then stereo (both) from there upwards?


----------



## Thomu (Apr 13, 2016)

I´m new to the whole EQ thing and it´s a bit OT but my guess is: Because you can´t locate the source for lower frequencies you get the sum of left and right channel at your listening position. It seems logical to me to flatten peaks by using stereo EQ. But maybe it´s possible to get rid of drops caused by interferences of both channels if you manipulate only one channel. I don´t know if i get it right but I will try that...


----------

