When A Pot Is Taken Out Of Commission...

Oster · October 14th, 2006, 01:39 PM

I wonder if anyone here might know the answer to this:

When a bass pot, say, is broken or disconnected - is there a 'default' bass setting on the amp?

The reason I ask is that the bass pot on the boost channel of my Marshall amp is clearly not operating. However the bass levels overall (compared to the clean, working, channel) seem fine.

I know it's a weird question but since the boost channel is nice and bassy with a broken bass pot (but not too bassy) I'm wondering if it's permanently in position - the setting it had when broken - or if the 'potless' tone settings on an amp (if there is such a thing) are at 12'oclock?

Tim Armstrong · October 14th, 2006, 01:51 PM

I don't know the answer to that, but I do know that Marshall amps were known back in the day for having tone controls that didn't do much!

Cheers, Tim

TC7 · October 14th, 2006, 02:04 PM

Quote:

Originally Posted by Oster

I wonder if anyone here might know the answer to this:

When a bass pot, say, is broken or disconnected - is there a 'default' bass setting on the amp?

I bet Joe Walsh could answer that one. ;-)

Oster · October 14th, 2006, 03:52 PM

Quote:

Originally Posted by Tim Armstrong

I don't know the answer to that, but I do know that Marshall amps were known back in the day for having tone controls that didn't do much!

Cheers, Tim

This is true. The working bass pot on the clean channel has a very subtle operation, compared to say, Fender controls. The amp, overall has 'it's sound' and the pots only add subtle change.

JohnnyCrash · October 14th, 2006, 07:45 PM

The way all guitar amps utilize their EQ controls is a funny thing. The mid control in particular (as it sort of cuts the effects of the Bass and Treble control as it's turned up).

The reasons the EQ works the way it does is good reading every guitar player should look up... but pretty much, the amp's main voice (or midrange character) is already there. The EQ controls slightly filter out from that main character. Look up "Baxandall EQ" on google or something. Most often there is a description of how typical guitar EQ works as compared to Baxandall type controls.

Anyways, away from the nerd stuff and back to your question...

The pot is a variable resistor. It depends by what you mean by "broken".

BrianF · October 14th, 2006, 08:30 PM

Typically when a pot 'breaks' ..it is usually the wiper contact that is 'broken' ie...the wiper contact gets dirty and loses contact with the main body of the pot. If this happens...the full value of the pot resistance would still be in the circuit..This should mean that the bass setting is at maximum....although careful review of the actual circuit would be needed to confirm this.

Oster · October 15th, 2006, 05:59 PM

Quote:

Originally Posted by BrianF

Typically when a pot 'breaks' ..it is usually the wiper contact that is 'broken' ie...the wiper contact gets dirty and loses contact with the main body of the pot. If this happens...the full value of the pot resistance would still be in the circuit..This should mean that the bass setting is at maximum....although careful review of the actual circuit would be needed to confirm this.

Thanks Brian - This is the sort of language/techtalk I lack.

Listening closely, the boost channel does seem to be full-on in the bass dept., compared to the other channel (which, as stated previously is a rather subtle tonally, anyway).

It's much better than the treble alternative!

October 14th, 2006, 01:39 PM	#1 (permalink)
Oster Friend of Leo's Join Date: May 2003 Location: Latveria Age: 39 Posts: 2,759	When A Pot Is Taken Out Of Commission... I wonder if anyone here might know the answer to this: When a bass pot, say, is broken or disconnected - is there a 'default' bass setting on the amp? The reason I ask is that the bass pot on the boost channel of my Marshall amp is clearly not operating. However the bass levels overall (compared to the clean, working, channel) seem fine. I know it's a weird question but since the boost channel is nice and bassy with a broken bass pot (but not too bassy) I'm wondering if it's permanently in position - the setting it had when broken - or if the 'potless' tone settings on an amp (if there is such a thing) are at 12'oclock?

October 14th, 2006, 01:51 PM	#2 (permalink)
Tim Armstrong Moderator Doctor of Teleocity Join Date: Mar 2003 Location: Berlin, Maryland, USA Age: 49 Posts: 10,262	I don't know the answer to that, but I do know that Marshall amps were known back in the day for having tone controls that didn't do much! Cheers, Tim __________________ http://www.moodswingers.org

October 14th, 2006, 07:45 PM	#5 (permalink)
JohnnyCrash Poster Extraordinaire Join Date: Mar 2005 Location: Lost Angeles and Orange County Posts: 7,128	The way all guitar amps utilize their EQ controls is a funny thing. The mid control in particular (as it sort of cuts the effects of the Bass and Treble control as it's turned up). The reasons the EQ works the way it does is good reading every guitar player should look up... but pretty much, the amp's main voice (or midrange character) is already there. The EQ controls slightly filter out from that main character. Look up "Baxandall EQ" on google or something. Most often there is a description of *how* typical guitar EQ works as compared to Baxandall type controls. Anyways, away from the nerd stuff and back to your question... The pot is a variable resistor. It depends by what you mean by "broken".

October 14th, 2006, 08:30 PM	#6 (permalink)
BrianF Friend of Leo's Join Date: Apr 2003 Location: Carlsbad, Ca Posts: 2,179 7 Photos	Typically when a pot 'breaks' ..it is usually the wiper contact that is 'broken' ie...the wiper contact gets dirty and loses contact with the main body of the pot. If this happens...the full value of the pot resistance would still be in the circuit..This should mean that the bass setting is at maximum....although careful review of the actual circuit would be needed to confirm this.