Custom made Parametric EQ Advice

quazimodo · #1 12-31-2009, 09:32 AM

I am building a parametric eq and at this stage adding and subtracting bands is just a matter of knowing what freq bands i want. This is something that needs experience i dont have. As a bassist what bands are most critical for me to be able to shape?
Would it be feasible to take 20, 40, 80 etc hz up to 20k, thereby giving a band on each octave with some overlap from one band into an another. Ive noticed some talk about guitarists wanting 2-3 bands all between 700 and 1400 hz, any particulars like this for bass?

jrmy · #2 12-31-2009, 09:38 AM

666 hz!!!!

Sorry - just kidding. Couldn't resist...

ogrossman · #3 12-31-2009, 09:42 AM

Just to be clear, are you taking about a "parametric eq" or a "graphic eq"? Your description: "20, 40, 80 etc hz up to 20k" seems more like a graphic with eleven bands. Are you going to have a Q adjustment for each band?

One way to figure out what bands you want would be to play with some software that has a real-time adjustable parametric filter and see what effect different filters have on a pre-recorded bass line. I have a mac computer so I'd use Garage Band to do this.

Passinwind · #4 12-31-2009, 09:49 AM

Quote:

Originally Posted by quazimodo

I am building a parametric eq and at this stage adding and subtracting bands is just a matter of knowing what freq bands i want. This is something that needs experience i dont have. As a bassist what bands are most critical for me to be able to shape?
Would it be feasible to take 20, 40, 80 etc hz up to 20k, thereby giving a band on each octave with some overlap from one band into an another. Ive noticed some talk about guitarists wanting 2-3 bands all between 700 and 1400 hz, any particulars like this for bass?

IMO and IME, make all the bands full range, like most commercial parametric EQs I've owned. If not full range, I'd want at least 3 octaves of center frequency sweep per band, with an octave and a half (or more) of overlap.

For what it's worth, it's more about the rooms than the basses as far as what frequency centers I use on a given gig. So unless we're playing the same rooms, I think it may be pointless to throw numbers at each other.

greenboy · #5 12-31-2009, 10:00 AM

Quote:

Originally Posted by Passinwind

IMO and IME, make all the bands full range, like most commercial parametric EQs I've owned. If not full range, I'd want at least 3 octaves of center frequency sweep per band, with an octave and a half (or more) of overlap.

For what it's worth, it's more about the rooms than the basses as far as what frequency centers I use on a given gig. So unless we're playing the same rooms, I think it may be pointless to throw numbers at each other.

This. All of it.

Bassamatic · #6 12-31-2009, 10:08 AM

You will hardly need anything above 8K or so. Concentrate on 3-4 bands that will cover 20 to 8K with some overlap.

You might start with a 1/3 band graphic and find what band centers make the most sense to you. Also, go out and review all the bass amps with graphics and see what their band centers are.

ryansalmond · #7 12-31-2009, 12:52 PM

To get an idea of what frequencies do what, I suggest downloading a frequency tone generator program for your computer and hooking it up to some powerful speakers. You can generate tones of different frequencies to see what they do. This is useful because it's hard to describe these things in words.

quazimodo · #8 12-31-2009, 05:55 PM

Thanks for the replies. I do indeed mean a parametric EQ, not graphic. My reason for asking about those centre freqs was more because of the way my brain compartmentalizes things, it felt more precise in my head. The electronics design of the thing is no problem, just the application, ive not used these before to be honest.

As for the room... dont i know it...

Anyway Cheers

scotch · #9 01-01-2010, 08:25 AM

Quote:

Originally Posted by quazimodo

I am building a parametric eq and at this stage adding and subtracting bands is just a matter of knowing what freq bands i want. This is something that needs experience i dont have. As a bassist what bands are most critical for me to be able to shape?
Would it be feasible to take 20, 40, 80 etc hz up to 20k, thereby giving a band on each octave with some overlap from one band into an another. Ive noticed some talk about guitarists wanting 2-3 bands all between 700 and 1400 hz, any particulars like this for bass?

Parametric bands that close together sounds like a recipe for really bad, phase mangled tone! It could probably be done, but when you start carving up your tone with any more than 4 or 5 parametric bands, things start getting weird! I've experimented with 5 band para's in the studio, and honestly, it was just too much!