- Thread starter cliff78
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Rod Trussbroken
Moderator
Linear is the correct taper for the Vol control and this is also shown on the EB schematics. Linear (as opposed to audio) allows even adjustment throughout the full rotation of the volume control. Linear is used for the Vol on the 3 band EQ pre-amps also.
An audio/log taper for the Vol control bunches up the adjustment to the upper limit of rotation...ie just a very small amount of rotation in the upper limit will give a pronounced increase in volume while, at the lower end, a significant amount of rotation will only give a slight increase in the volume.
Although the Pre-EB schematic shows the Vol pot as having an audio taper, I've actually seen some Pre-EB Rays with a linear taper Vol control. However, my 1979 Bass has an audio taper Vol pot which is annoying to adjust and I intend changing it when I get around to it.
I used to think the correct taper should be Audio as the human ear is log/audio with respect to volume while the ear is linear with respect to tone...yet the Pre-EB and EB schematics both show the tones (Treble and Bass) as audio instead of the expected linear. But an audio taper for the Treble and Bass is correct. Using a linear for the tone controls (I've tried using a linear for the Bass) will produce the same result in adjustment as if using an audio taper for the Vol.
EDIT: I don't know why Pre-EB used audio. Perhaps they had large stocks of the audio taper at hand??!!!
An audio/log taper for the Vol control bunches up the adjustment to the upper limit of rotation...ie just a very small amount of rotation in the upper limit will give a pronounced increase in volume while, at the lower end, a significant amount of rotation will only give a slight increase in the volume.
Although the Pre-EB schematic shows the Vol pot as having an audio taper, I've actually seen some Pre-EB Rays with a linear taper Vol control. However, my 1979 Bass has an audio taper Vol pot which is annoying to adjust and I intend changing it when I get around to it.
I used to think the correct taper should be Audio as the human ear is log/audio with respect to volume while the ear is linear with respect to tone...yet the Pre-EB and EB schematics both show the tones (Treble and Bass) as audio instead of the expected linear. But an audio taper for the Treble and Bass is correct. Using a linear for the tone controls (I've tried using a linear for the Bass) will produce the same result in adjustment as if using an audio taper for the Vol.
EDIT: I don't know why Pre-EB used audio. Perhaps they had large stocks of the audio taper at hand??!!!
Last edited:
Ken Baker
Well-known member
In the case of passive basses, a log taper pot makes sense because we measure sound in db, which is a logarithmic curve; all of which is driven by the way our ears work. Take a look at your average passive Jazz or Precision and you'll find log taper pots.
Active basses change all this by allowing the overall circuit to control the output. In the case of most active basses, it's common to see linear taper pots. I say most because there are some rule breakers out there.
Active G&L L-series basses use an onboard preamp that acts like an outboard preamp. The circuit is used to make the output a little hotter and to alter the output impedance for quiet operation. Building the electronics this way allows the instrument to be run active or passive, or even without a battery, and retain full volume, switching, and EQ control in both modes. All switching, volume, and EQ controls are outside of the preamp and the volume control is audio taper. The tradeoff is that the EQ is passive (cut-only), which isn't a problem when considered in context with the overall package.
While I'm not familiar with the pre-EBMM basses, a look under the hood would probably reveal an electronics package very similar to the early G&L instruments; both of which have their roots with Leo and CLF Research.
Ken...
Active basses change all this by allowing the overall circuit to control the output. In the case of most active basses, it's common to see linear taper pots. I say most because there are some rule breakers out there.
Active G&L L-series basses use an onboard preamp that acts like an outboard preamp. The circuit is used to make the output a little hotter and to alter the output impedance for quiet operation. Building the electronics this way allows the instrument to be run active or passive, or even without a battery, and retain full volume, switching, and EQ control in both modes. All switching, volume, and EQ controls are outside of the preamp and the volume control is audio taper. The tradeoff is that the EQ is passive (cut-only), which isn't a problem when considered in context with the overall package.
While I'm not familiar with the pre-EBMM basses, a look under the hood would probably reveal an electronics package very similar to the early G&L instruments; both of which have their roots with Leo and CLF Research.
Ken...
Last edited:
58super
Well-known member
There's a reverse audio taper pot in there thats a PIA to find as well.
great info on this one rod. i ordered the 25k pot from eb. o got the linear taper.. i was planning to change it to audio. but because of this insight i'll be using the linear taper instead. thanks alot
Rod Trussbroken
Moderator
The Treble pot is a reverse audio
