EQ setting for FRFR cab

  • Hey guys! I‘ve bought a Matrix FR212 cab and really like it with my bias rack. But in most of my sounds it‘s a little bit boomy in the bass and harsh in the highs. I tried different irs with the same result. Has anyone an idea what to do? I tried some eq-ing, but may be there‘s a better way?

  • A2

    I’m hoping someday Bias will have a multi and compressor to deal with at least the lows. Eq will work for what you want to do, but it also affects the times when there is no problem, and makes a new problem there. A global compensation eq for different rooms, different amps would be cool as well. But per patch MBC would be awesome

  • @daniel-g

    Instead of inserting EQs, play with the Low-Cut and High-Cut in the Preamp. There are also the pre-eq and post-eq setting in the preamp. I actually work with these before inserting the two EQs somewhere. Let me know how you make out.



  • Also play with the bright and normal switch in the preamp section to address the high-end.

  • Many thanks to you all. I‘ll try the high/low cut suggestion at first. What adjustment would you start with?
    This software parameters are so complex, so many possibilities, hard to figure out the best way... Does there exist a manual where you can read about every function/knob in bias?

  • Matrix is supposed to be real flat, so maybe you have to re-do your tones through that. I've read many say each rig has to be different. Note that preamp adjustments will affect the body of the tone, whereas post eq will affect the overall sound, the sort of halo of the tone.

  • The EQ section of the Amp has both shelving and cut off filters at each end of the spectrum they are perfect for shaping the edges of your amp frequency response.

  • @As I noticed, the eq can be moved before or after the cabinet, does this make any difference? Which frequencies would you cut?

  • A2

    @daniel-g Look at it on a spectral analyzer if you can.

    What I usually do at least when dealing with frequencies in a mix is to identify places where there is a "one note bass" problem. This phenomenon happens at low notes where the pitch to frequency conversion is extremely close together for instance at C 131hz D is at 147. If there is a large bump up in that sort of area in a particular cab sound, it can make all those notes blend together. Its not quite as easy when dealing with a real cab, but If you have a keyboard or a seven string, you can play notes around a trouble area through a real cabinet and see if there is a volume jump there. You might save different EQ's for different FRFR setups

  • @pipelineaudio Good point... Cabs also have natural points of resonance. A bandpass type filter centered on the hyped frequency is a cool tool. I really like the built in parametric in Bias. It is really useful and well done.

  • @rick-shapiro Hey Rick, your advice with the low and the high cut in the preamp-section was quite helpful, thank you very much! I filtered out frequencies over 4kh and under about 80-120h. But now in Bias Amp 2 I can‘t see the frequencies that I cut out, right? Did they really removed the display for that?

  • A2

    A multiband compressor is seriously what the doctor ordered for this

  • Interesting I always use the EQ in the signal chain. Need to look at the back of the amps and try to get those settings down.
    Have learned a lot over the last year using amp sims but still have to come up with good tweak plan - strategy (as opposed to just tweaking the knobs on the front of the amp).

  • @pipelineaudio I‘m sure that‘s right, but I need it for my bias rack...

  • @daniel-g Like I noted, look at the parametric EQ on your amp model. It gives you 8 bands of fully customizable control and there are two of them. If you are willing to dig into them the frequency sculpting possibilities are huge.

  • A2

    If there is an evil, awful resonance trying to ruin your day, one thing you can do is:

    Change to a clean sound

    1. Slowly play one note at a time, and try to pick them just as hard as each other (if you have a signal generator, then WAY better but you can do this with your guitar)
    2. Go up and down the neck and see if you hear something WAY louder
    3. If at all possible, play that same note on a different string and see if the volume jump is still there
    4. Use a chart like this and convert the note that jumped out to HZ. https://pages.mtu.edu/~suits/notefreqs.html
    5. Ideally, set up a parametric so that you have this frequency, the frequency of the note an octave below and the note an octave below as three separate bands
    6. Try turning up and down these bands and see if the problem gets worse or better

    Often, if you find you lost too much "thud" when you turned down the offending note enough to fix the problem, turning up that same note an octave or two higher can give the illusion that the low end is still there, but without making the trouble. This is how entire marketplaces of "bass enhancing" devices and speakers work, and it can be pretty effective

  • Thank you guys! I‘ll try this. Will need some time... I tried to use the eq analyzer tool , too, but it seems that this doesn‘t work with bias rack...

  • @pipelineaudio said in EQ setting for FRFR cab:

    1. Ideally, set up a parametric so that you have this frequency, the frequency of the note an octave below and the note an octave below as three separate bands

    I'm not understanding. Those latter two seem the same to me.

  • A2

    Oops, I forgot a comma. Should be:

    This particular note, an octave below that note and an octave above that note

    So for instance, the all too common problem area in many 4x12's, D#3 at 155 hZ

    You'd want to roughly start with three bands at D#2 = 77hz, D#3 = 155hz, and D#4 = 311hz

    Of course, this is just an example, and often you'll find a cab with serious resonance at a different place

    I used to make a plugin for dealing with kick drums and toms where you could find the resonant frequency and then turn up or down octaves of that fundamental (including subs). Maybe I should remake that for guitar cabinets

  • A comma wasn't necessary. You said below twice. I was thinking you meant below and above, and you did.

    Somewhat related: with amps the range that 'clogs' up the tone is around 250hz....yet to my ears this is where the body of a sound is, and what I always miss if not there......