Understanding the rotary dial EQ concept

[ryco]

OK, I'm technically "challenged".
Quick question:

Some amp controls feature EQ knobs from [clockwise] 1 to 11.

Some amp controls feature knobs set at 12 o'clock is "flat" = dial left is "cut". Dial right is "boost".

Q: Does this mean rotary dials are set to "5" would be "flat" and down to 1 is "cut"; and/or 6 to 10 would be "boost".


An aside: seem to recall on Sunn Coliseum 300 bass amps had 7 EQ controls and one had to dial in each frequency band. All dials turned left to "0", even with gain and master volume turned "up" = no sound until frequency EQ dials were turned clockwise. Thought that was an interesting concept - actually building and shaping your tone "dialed in" literally from nothing.

 

[mambo4]

probably a question for the amp & speaker forum.
how the knobs work depends on the amplifier circuitry.

the 2 basic EQ flavors are filter and parametric

filter EQ is cheaper and much more common
at 0 it removes (filters) the low/mid /high frequencies , at 10 it lets them pass to the amplifier circuit
also called subtractive EQ. so "flat" EQ is actually "remove some" of the frequencies.
Don't make the mistake of thinking subtractive EQ means your being robbed of tone. They are actually extremely useful for sculpting tone. In fact removing what you don't want is usually superior to adding more of what you want than is present in the source signal.

parametric EQ is more expensive and is a true boost/cut
parametric knobs usually have an associated knob for choosing a specific frequency range to boost/cut. these are typically mid range EQs, and are not numbered 0 to 10, but something like -10 to +10

Then of course there are the 'made up' EQ knobs like 'contour' or 'aural enhancer' which do different things to different frequencies.

Most manuals will describe which frequencies the knobs effect and whether they filter or boost/cut

your ears will be the best judge of exactly what the knobs do

 

[ryco]

Thank you for your answer, mambo!
Mods can move this wherever

Was just curious if rotary EQ is set bass @ 5, mid @ 5, treble @ 5; = would that be considered "flat".

 

[lokikallas]

Yes, 5 is generally considered “flat” on amp eq.

 

[HelpImaRock]

You've acknowledged the two different EQ styles, active and passive. But there are some misconceptions.

1. You're correct regarding active. "Noon" is flat. Cut or boost to taste.
2. You're incorrect on passive. "Flat" depends on the tone stack. Many of the differences between amps have more to do with the tone stack than anything else. The treble control usually has the most control over an amp in a Fender style tone stack. But there are other topologies and it's difficult to say how the controls operate without specific examples.

I would definitely ask this question in the amp forum.