Go Back   TalkBass Forums > Bass Guitar Forums > Bass Guitar Forums > Amps [BG]
Register Rules/FAQ/CUP Members List Search Today's Posts Mark Forums Read



Supporting Membership
Thank You

Latest Supporting Member
Donate to Upgrade Today

Reply
 
Thread Tools Search this Thread
  #1  
Old 11-24-2013, 01:03 PM
Registered User
 
Join Date: Jun 2013
Location: Chicago area
Amp EQ settings

As I understand it basic combo amp EQ, bass-mid-treble, knobs are just variable resistors, my question is:

Shouldn't all 3 be turned up full as a starting position to get the full signal coming through, and then backed down to cut off whatever frequencies I don't want? Same idea as the "tone" knob on the bass, start with full on, then back off.

Cheers.
__________________
Yamaha RBX170EW, Basslines SPB-3, Ernie Ball Extra Slinky, GK MB112-II, Yamaha V60
  #2  
Old 11-24-2013, 01:45 PM
B-string's Avatar
Registered User
 
Join Date: Nov 2008
Location: Lake Havasu City, Az USA
Supporting Member
Not necessarily true, Fender style tone stacks as an example are boost bass and treble (2 out of 10 is "flat") and cut only on mids (10/10 "flat").
__________________
Just call me B-String 2
GK Club #488 Big Cabs #175 Peavey Amps #92 50+ Club #44 Grumpy Old Fart #2
  #3  
Old 11-24-2013, 01:46 PM
JimmyM's Avatar
Registered User

Endorsing: Ampeg Amps, EMG Pickups
 
Join Date: Apr 2005
Location: Apopka, FL
Supporting Member
Hey, if it works for you, that's cool.
__________________
Ampeg Portaflex Club #1
Quote:
Originally Posted by beans-on-toast View Post
Tweeters are for the birds.
  #4  
Old 11-24-2013, 01:51 PM
Bassist4Eris's Avatar
Non Serviam
 
Join Date: Aug 2012
Location: Scotia NY
Supporting Member
Gain structure: a scary-sounding term that actually means something quite simple, namely, every step in your signal chain puts out a certain amount of signal, which must then be handled by the next step. And the next step will behave best when being hit with neither too little nor too much signal. I would bet that if you tried turning your EQ knobs all the way up, your tone would suffer due to the power amp being hit with higher-than-optimum signal. But hey, it's worth a try.
__________________
Quote:
Originally Posted by JimmyM View Post
...and all of the soul-sucking forces out there who think I should fulfill their idea of what I should be doing as a bass player can suck their own souls.
  #5  
Old 11-24-2013, 01:56 PM
Registered User
 
Join Date: Aug 2009
Location: New Zealand
Good point on avoiding crazy overdrive. Otherwise, where you start doesn't much matter.

It is always interesting to find the nominally flat positions on TB and see if you agree with the amount of baked in midscooping commonly found at noon positions.
__________________
Team Trace Elliot #1, IWNBARMPB Prezident, Mediocre Bassist #399, Old Basstard #86, PBBBC #2
  #6  
Old 11-24-2013, 02:12 PM
Registered User
 
Join Date: Jun 2013
Location: Chicago area
Thanks for the comments guys.
I'm pretty new at this and really trying to hear what I'm playing flat. I'm guessing "Noon" on the EQ knobs and full on the bass "tone" is the best flat starting point?
__________________
Yamaha RBX170EW, Basslines SPB-3, Ernie Ball Extra Slinky, GK MB112-II, Yamaha V60
  #7  
Old 11-24-2013, 02:16 PM
ArtechnikA's Avatar
I endorsed a check once...
 
Join Date: Feb 2013
Location: SEPA
GOLD Supporting Member
Quote:
Originally Posted by ironjohn View Post
I'm guessing "Noon" on the EQ knobs and full on the bass "tone" is the best flat starting point?
As previously stated - without knowing what amp, there is no way to guess.

(I'd guess the answer is in your amp's manual...)

If it uses the "Fender style" EQ, 'flat' is 2-10-2.
Not just Fender uses this model...

On some, all-numbers-equal is flat. There are other models.

Tell us what you've got, and someone here will know how to make it flat...
__________________
Club Hartke - #337 | Steinberger Synapse Clubb - #8 | Fretless - #886 | Darkglass - #77
This old man, he plays 6...
  #8  
Old 11-24-2013, 02:23 PM
Registered User
 
Join Date: Jun 2013
Location: Chicago area
Thanks.
I have a simple Fender Rumble 30. I didn't see anything in the very limited manual about flat settings, e.g., 2-10-2.
__________________
Yamaha RBX170EW, Basslines SPB-3, Ernie Ball Extra Slinky, GK MB112-II, Yamaha V60
  #9  
Old 11-24-2013, 02:24 PM
Zoa Zoa is offline
Registered User
 
Join Date: Dec 2009
Quote:
Originally Posted by ironjohn View Post
Thanks for the comments guys.
I'm pretty new at this and really trying to hear what I'm playing flat. I'm guessing "Noon" on the EQ knobs and full on the bass "tone" is the best flat starting point?
It really depends on the individual amp.
__________________
FREE JAMES BROWN WITH HIS DEVO HAT.
  #10  
Old 11-24-2013, 02:34 PM
ArtechnikA's Avatar
I endorsed a check once...
 
Join Date: Feb 2013
Location: SEPA
GOLD Supporting Member
Quote:
Originally Posted by ironjohn View Post
Thanks.
I have a simple Fender Rumble 30. I didn't see anything in the very limited manual about flat settings, e.g., 2-10-2.
I had a look - you're right - it doesn't.
It -does- mention full power rated with EQ flat, and the individual controls are described as being 15dB.

So it does give the impression that "center" is 0, and that all at center would be a good starting point for what they think is flat.
__________________
Club Hartke - #337 | Steinberger Synapse Clubb - #8 | Fretless - #886 | Darkglass - #77
This old man, he plays 6...
  #11  
Old 11-24-2013, 02:35 PM
B-string's Avatar
Registered User
 
Join Date: Nov 2008
Location: Lake Havasu City, Az USA
Supporting Member
I didn't find a flat setting either but it is an active EQ so with all tone controls full up you would have a 15db boost (over flat) at 60Hz, 630Hz and 6KHz. Far from a good "starting point".
__________________
Just call me B-String 2
GK Club #488 Big Cabs #175 Peavey Amps #92 50+ Club #44 Grumpy Old Fart #2
  #12  
Old 11-24-2013, 02:41 PM
Registered User
 
Join Date: Jun 2013
Location: Chicago area
Wow, thanks a lot guys. You've been a big help.

Cheers.
__________________
Yamaha RBX170EW, Basslines SPB-3, Ernie Ball Extra Slinky, GK MB112-II, Yamaha V60

Last edited by ironjohn : 11-24-2013 at 02:50 PM.
  #13  
Old 11-24-2013, 02:49 PM
Registered User
 
Join Date: Jun 2013
Location: Chicago area
One last thing.
I'm I correct about the bass "tone" knob?
Turning it up, just bleeds off high frequencies away from flat?

Cheers
__________________
Yamaha RBX170EW, Basslines SPB-3, Ernie Ball Extra Slinky, GK MB112-II, Yamaha V60
  #14  
Old 11-24-2013, 02:51 PM
Fuzzbass's Avatar
Registered User
 
Join Date: Dec 2001
Location: Maryland, between Bawlmer & DC
Supporting Member
Quote:
Originally Posted by ironjohn View Post
Shouldn't all 3 be turned up full as a starting position to get the full signal coming through, and then backed down to cut off whatever frequencies I don't want? Same idea as the "tone" knob on the bass, start with full on, then back off.

Cheers.
The tone knob on a passive bass (traditional Fender bass, no battery) is also passive: there is no boost, it cuts higher frequencies only. In that case, the flattest tone is with the tone all the way up, just as you said.

However very few amp EQs are passive. Most are "active", that is, they can cut and boost. So, for flattest response you don't want cut or boost.

With most amps, flat is at noon, but as noted above, this is not always true.
__________________
Ken Fiester
HighTest: classic/modern hard rock
Too Many Daves: Motown/Stax R&B, classic rock
Retro Deluxe: roots/blues/rockabilly/country
Secret Addiction: classic rock/dance pop/modern country
  #15  
Old 11-24-2013, 02:51 PM
ArtechnikA's Avatar
I endorsed a check once...
 
Join Date: Feb 2013
Location: SEPA
GOLD Supporting Member
Quote:
Originally Posted by ironjohn View Post
Turning it up, just bleeds off high frequencies away from flat?
On mine, CW is more treble, CCW is less.
__________________
Club Hartke - #337 | Steinberger Synapse Clubb - #8 | Fretless - #886 | Darkglass - #77
This old man, he plays 6...
  #16  
Old 11-24-2013, 02:54 PM
Registered User
 
Join Date: Jan 2006
Location: Brookfield, CT
Quote:
Originally Posted by ironjohn View Post
One last thing.
I'm I correct about the bass "tone" knob?
Turning it up, just bleeds off high frequencies away from flat?

Cheers
If you mean 'up' as in counterclockwise, yes. It just bleeds highs to ground.
The problem with your previous inquiry is that you'd create three large bumps in your frequency response. It wouldn't bring 'everything' up. Just three relatively narrow areas.
__________________
Quote:
Originally Posted by Bassist4Eris View Post
My reggae skills are rudimentary enough that I just play whatever the original guy played. :)
  #17  
Old 11-24-2013, 02:54 PM
B-string's Avatar
Registered User
 
Join Date: Nov 2008
Location: Lake Havasu City, Az USA
Supporting Member
Quote:
Originally Posted by ironjohn View Post
Wow, thanks a lot guys. You've been a big help.

Cheers.
That is why a good many of us come here.
__________________
Just call me B-String 2
GK Club #488 Big Cabs #175 Peavey Amps #92 50+ Club #44 Grumpy Old Fart #2
  #18  
Old 11-24-2013, 03:02 PM
Registered User

Use of this field for any other purpose is prohibited
 
Join Date: May 2006
Location: austin,tx
Quote:
Originally Posted by ironjohn View Post
One last thing.
I'm I correct about the bass "tone" knob?
Turning it up, just bleeds off high frequencies away from flat?

Cheers
On the bass, the further you turn it down, the more treble it bleeds off,. Most amps other than little practice amps that only have one tone knob, usually don't work like that. At least the bass and treble knobs, and often the mid too, can add rather than just subtract from the sound. On a lot of them, having the bass full up usually means more bass than the speaker can handle.

Long and short of it is, just adjust things to where it sounds good while listening to the speaker for signs of distortion or stress. If it distorts, turn down the bass, the volume, or a bit of both.
  #19  
Old 11-24-2013, 03:31 PM
Registered User
 
Join Date: Aug 2009
Location: New Zealand
Noon starting off point can't go wrong.

Most any amp will go a lot louder before distortion if the bass knob is only adjusted downwards.
__________________
Team Trace Elliot #1, IWNBARMPB Prezident, Mediocre Bassist #399, Old Basstard #86, PBBBC #2
  #20  
Old 11-24-2013, 06:54 PM
Steve Dallman's Avatar
Registered User
 
Join Date: Mar 2006
Location: East Central Wisconsin
Supporting Member
The Fender tone stack is a passive circuit that has an inherent mid cut. The controls are very interactive, meaning, changing one control will change the way the other controls work. All controls at 10 will let the most signal through, but it will not be "flat." As others have said, the closest you can get to "flat" with a Fender tone stack is with the mid cranked, and the bass and treble seriously cut...2-10-2. Turn all the tone controls down on a three band Fender EQ and there will be no signal.

Ampeg EQ is different. The bass and treble use a passive Baxandall tone stack that acts like an active, cut and boost EQ. Center is flat, and the controls are not interactive. The mid is an active, boost and cut circuit using an inductor based circuit. Center is flat.

Some amps are variations of a Fender stack, like Hiwatt and others. Many are all active EQ's. The EQ design has a major effect on the signature tone of an amp.

So with some amps, "flat" is with the controls at center. Others take some knowledge of the passive design to achieve a "flat" tone. Even though a Fender has an inherent mid cut, it sounds great and is a tone we all know and love...at least for guitar. Marshall and Vox have very similar tone controls to Fenders, but with the mid cuts in different places and the tone controls let different frequencies through.

Some Fender type tone controls have only bass and treble. The midrange is actually preset to around 6-7...the blackface Bassman for instance. The closest to "flat" is with the bass and treble turned all the way down...and it doesn't sound very good set that way.

With a two band, baxandall circuit, as on an Ampeg B-15, center is "flat." There is no mid control, but if you turn the bass and treble up, the mids remain "flat" so the result is a "mid cut." If you want a mid boost with a Baxandall circuit, you turn the bass and treble down. The mids remain at center so it sounds like the mids are boosted. (the volume will have to be reset to make up for the volume loss due to the bass and treble being turned down.)

The circuits are varied. The passive ones use caps to pass or shunt frequencies with resistors to control the "shape" and response of the circuits. Active circuits commonly use gain stages with the caps in sort of a gain feedback loop of gain setting action of the gain stage.

Not just simple "resistors" but various circuits using multiple caps, resistors, sometimes inductors, transistors, op amps, tube stages, potentiometers, etc. The placement of the EQ circuit in the gain staging of a preamp matters as well. The first Fender Bassmans use a lossy passive tone stack. There are preamp gain stages to raise the signal so the loss is compensated for. The first Bassmans put the compensating gain stages all BEFORE the tone stack. The multiple stages before the tone stack created a preamp that had little headroom and easily distorted...not great for bass but guitar players loved it.

Later Bassmans changed the gain staging. The had an initial preamp stage, the lossy tone stack, and put a recovery gain stage just after the lossy tone stack. The volume control was also placed between the gain stages.

This gave the preamp much more headroom, and Fender used this type of tone stack in blackface, brownface, and silverface amps and still use it today. Unfortunately, Fenders power amps were usually not large enough for bass players of the day, compared to the bass giants like the SVT, Acoustic 370, the big Sunn's, etc.
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Visit TalkBass on Facebook   Download our iOS app   Download our Android app

All times are GMT -6. The time now is 11:00 PM.




2012 Talk Music Group Inc. All rights reserved.
Play guitar too? Visit TalkGuitar.com
Powered by vBulletin® Version 3.6.12
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.