Any tips on where to set LF Res using Matrix into Thiele cab with EV12L?

You have set it loud, play the low string, vary the LFR and at a point you'll feel the cabinet resonating.
 
Thanks. I've read this before and tried it before, but I guess I'm not hearing it (or I don't know what "resonating" feels like).
 
You can't miss it when adjusting the frequency. It's that point where the cab interacts with or "catches" the input signal, and you notice extra bass. But you have to play it loud. Use a Looper block before the Amp to make it more convenient.
 
yek said:
You can't miss it when adjusting the frequency. It's that point where the cab interacts with or "catches" the input signal, and you notice extra bass. But you have to play it loud. Use a Looper block before the Amp to make it more convenient.
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I recently did this on my two cabs.

Here is how I did it taken directly from the wiki which is a quote from Cliff. "One way to find the SRF is to put a Filter block after the amp block. Set the type to Peaking, Q to 5 or so and Gain to 10 dB. Start with a Freq. of 50 Hz. Play some chugga-chugga and slowly adjust the Freq. until you hear and feel the cabinet resonate. Make a note of the frequency. Remove the filter block and set the amp block SRF to match. 4x12s typically have an SRF of between 80 and 120. Open back cabs are typically a bit lower."

I used a looper block to crank some heavy low E and F# chords and had the volume loud, ~95 dB. I swept the frequency value in the Filter block while listening and touching the speaker cab. I sat close enough and put my hand on the cabinet so that I could actually feel the vibration when the resonance frequency hits. As Yek, said you can't miss it. Listen for the increased bass response AND the vibration of the cabinet at that frequency. I do recommend working fast to find the frequency as being that close to the cab at that volume is going to do some hearing damage after awhile.

Here are the SRF values (crudely measured, I admit) if anyone is interested.

VHT Fat Bottom 2 x 12 cab with EVM12L speakers. 90 Hz
FLITE 1 X 12 cab with EVM12S speaker. 83 Hz.

Hope this helps.
 
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bjjp2 said:
Thanks. I've read this before and tried it before, but I guess I'm not hearing it (or I don't know what "resonating" feels like).
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The trouble with doing this with a 12L is that its published low res freq, 55hz, is below the lowest note on a guitar.
So to do the bass-note/sweep-the-freq routine with these speakers you'll need to use a bass instead of guitar.
Or you might try using a pitch shift effect in the Axe to lower your guitar's pitch an octave.
that's what I did. (see below)
The synth block could be used too I suppose.

Jay Mitchell once told me that when these drivers are put into a cab that the low res freq goes up around 10hz.
So his suggestion was to set it at 65hz in the Axe's amp block for use with my cabs.
But I'm using open back 1 X 12 cabs.
Your Thiele might be a bit different.

When I did the sweep test, using a pitch shifted lower octave with my guitar, my cab seemed to be resonating at 69.3 hz (still well below the low E on a standard tuned guitar) and that's the number I use now in all my presets.
It does seem to help with the overall feel and polish of my presets.
 
I'd be curious to know if the OP came up with a value he is using. I'm using 72 Hz with my Matrix GT 800 and an EV12L Thiele cab.
 
ethomas1013 said:
I'd be curious to know if the OP came up with a value he is using. I'm using 72 Hz with my Matrix GT 800 and an EV12L Thiele cab.
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I tried to do this by feel, as many recommended, using a bass, and I came up with around 125hz. My cab is actually a Glaswerks Thiele-style. I may be off because, I said, it's not obvious to me. I'll try yours too.
 
I didn't actually try to figure it out. I read somewhere that someone else using a Mesa Thiele with the EVM 12L was using 72 Hz. So that's what I have been using and it seems to be about right, but I'm certainly not an expert.
 
Wow, hold it for a sec…
I just read it, I'm not sure I've understood what the intention of that procedure is.
Would be happy to read a short explanation, way make the cab vibrate or better what is the meaning of this ?
Thanks.
 
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