Markbass SA450 EQ Question

Discussion in 'Amps and Cabs [BG]' started by Mr.T., Jan 13, 2009.

  1. Mr.T.

    Mr.T. Guest

    Nov 17, 2006
    Cornwall, UK

    The two mid frequency selection pots on my SA450 sweep from:
    Low Mid = 100 to 700hz
    High Mid = 800hz to 6khz

    Could someone let me know what frequencies are selected when the controls are at 12 o'clock?

  2. Well, it should be about half way in-between:D

    So, around 400hz on the low mid (pretty close to the fixed low mid freq control on the LMII), and around 3.4K or so on the hi mid (quite a bit higher than the 800hz fixed control on the LMII).

    Of course if the mid volume controls are at noon, no frequencies are impacted.

    It's a great head IMO. Also, you have the top and bottom ranges reversed.... the low goes to 800 and the high starts at 700 (so mid is more like 450 and high is more like 3.3K... close enough!), so there is some overlap, which is usually how these things are designed.
  3. alexclaber

    alexclaber Commercial User

    Jun 19, 2001
    Brighton, UK
    Director - Barefaced Ltd
    Halfway in between in terms of notes, not frequencies, is much more likely.

  4. Sorry Alex... I'm not following. Wouldn't that be the same thing (Edit: I guess you are saying most are non-linear with regard to frequencies)?

    The taper on the semi-parametric sounds reasonably linear to me, although I haven't really given it much thought, since I pretty much run the amp flat.
  5. alexclaber

    alexclaber Commercial User

    Jun 19, 2001
    Brighton, UK
    Director - Barefaced Ltd
    12 notes in every octave so the lower you go the fewer Hz between each note.

  6. +1.. the non-linear thing I mentioned above. I just took a look at my Thunderfunk, which has the frequencies printed around the semi-parametric bands, and there is the non-linearity that you mention (i.e., equal intervals on the lowest knob, for example, are 35, 40, 50, 60, 80, 120, etc.).

    If that's the case, then I guess my estimated center points are a bit too high (so maybe actually 400 and 2K or something of that sort). With a fixed, relatively wide Q, it's hard to hear exactly where the center point of the Q distribution is (for me anyway).

    Thanks Alex!
  7. Tim1


    Sep 9, 2005
    New Zealand
    Having started out with everything flat and just using the VLE, in recent weeks I have really appreciated the parametric aspect of the 450's tone controls. I have had to use several different cabinets recently and have just been taking my 450 to gigs, the ability to sweep the high mids and the frequency positioning of the low tone control means I can tweak any cab very quickly to "my" sound. Certainly one of the strengths of Markbass is that they are inherently useable flat, and for a while that blinded me to the ease of use of their excellent tone controls. I must say I am very glad I bought the 450 over the LMII for this reason.