What creates a bass amp's "voicing"?

[FingerDub]

I had never heard this term before joining here, but I see it mentioned a lot. Lots of talk about an amps "tone" as if there is a massive variety. I'm skeptical, but, I'm not an amp or electronics pro, so bear with me.

AFAIK, amps have a preamp stage before it reaches the power supply. It is my guess that this is what primarily "voices" the tone. You then have a variety of knobs depending on the amp you can use to change the sound.

I can't imagine that the preamp does much more than set specific frequency points for boost and cut, and may have some sort of circuit to reduce noise or similar. But, at the end of the day, can't you just adjust one amp compared to another so that the frequencies that are boosted or cut are the basically the same? Granted, some amps are much more complex with more options for tone shaping, and it may vary slightly from amp to amp but the idea is the same.

Anyway, with all the amps I've used throughout the years, I've been able to get all the basic sound setups I've ever wanted. A scoop, mid boost, whatever, and regardless of the amps quality, it has varied from amp to amp very little IME. I'm not hating on the people that like or buy expensive preamps "for the tone", I just don't know what they are paying for.

 

[Hamish MacCleod]

I'm sure the "tech" guys will chime in pretty soon but here is my 2 cents: Preamp is the EQ/tone shaper in an amplified system. I can play an Ampeg and it sounds like me playing an Ampeg. I can play an Acoustic 370 and it sounds like me playing a 370. So, if there is a brand/model of amp that is closer to the sound I'm after, thats what I'll choose. If I played through an Acoustic 361 I'm not going to sound like Jaco... I'll sound like me playing through the 361. However, if I want to sound closer to Jaco I'll be better served starting with a 361 than say an SVT. In my experience [YMMV] I'm not going to get an Acoustic 361 sound out of a Fender amp.

For awhile I used power amps with multiple preamps to get "the tone". Discovered I was using Ampeg-ish B15 type preamp settings for 90% of what I was playing. I ditched the power amp and rack full of pres for an Ampeg PF800.

Four factors contribute to "my sound": My skill [or lack there of], my cabinet, my amp/preamp, and room acoustics.

FWIW, like you, I can get my sound out of almost any amp/preamp but the Ampeg gets a lot closer to the sound that moves me... now.

When I started playing I was doing 60's-70's rock [Acoustic Controls Corp amps got me there] Now doing much more Blues and Blues/Rock/Fusion, and experimental music.

H

 

[BurningSkies]

There are characteristics in an amp that are not 'preamp tone stage related'. That may be in the early gain stages or after that fact. Things like harmonic (and not so harmonic) distortion, compression characteristics, etc. I find that my current preamp shapes the note envelope differently and specifically from other preamps.

 

[Killed_by_Death]

Most amps aren't "flat". Some assume that when all the EQ knobs are at noon that they're flat, but they'd be wrong, most of the time.

 

[agedhorse]

There are all kinds of things that are responsible for an amp's voicing, some intentional and some are lucky happenstance (like the venerable Fender tone stack).

Things like eq, filters, the non-linear way some circuits behave when loaded heavily, compression, frequency dependent compression, harmonics generation and their distribution, etc.

 

[beans-on-toast]

People associate voicing with the tone stage and the speaker. Everything in an amp contributes to how if performs and sounds. This includes the preamp, the power amp, in the case of a tube amp the output transformer, the speakers and cabinet, and the power supply. As mentioned, an amp will perform differently depending on how hard it is driven.

Preamps and power amps are made up of stages. Each stage contributes to the sound in a different way based on its design. These stages interact with the power supply which is the heart of the amp. The power supply will sag depending on how it is taxed. This affects how each stage performs. Stages can be driven into nonlinear operating regions depending n the input and the power supply sag.

All these "features" interact to deliver the character of the amp.

 

[FingerDub]

But, can most amps, with proper EQ'ing be made to sound like any other amp?

If not, which is one amp whose voicing could not be duplicated?

 

[Hamish MacCleod]

But, can most amps, with proper EQ'ing be made to sound like any other amp?

If not, which is one amp whose voicing could not be duplicated?

1. No. Not in my experience
2. ACC 371, ACC 361 [IME/IMHO]
If you changed the first sentence to "Can 'some' amps, with proper EQ'ing be made to sound like 'some' other amp? I'd say some can, the Kemper and AxeFX amps will get you there but the cost of admission is high.
H

 

[beans-on-toast]

Like your origanal question, the answer is not straight forward. Some amps can be EQ'ed to sound close to another, not most though.

People spend their life chasing tone, buying and selling instruments and amps. Some find what they are looking for, others never do so they compromise. Also keep in mind, there is the right amp for the right application. My B-15 is low wattage, it works in certain cases. A higher wattage amp is needed for higher volume venues. So you need more than one amp. Some thing for instruments. Different tools for different jobs.

 

[Hamish MacCleod]

My B-15 is low wattage, it works in certain cases.

That is why I use a PF800, gets me close to the B15 tone at higher volumes. If I could afford one I'd buy a Kemper, rent all my favorite sounding amps, rent a studio, profile everything and be done... my pockets aren't that deep.
H

 

[JJR58]

These 2;

Most amps aren't "flat". Some assume that when all the EQ knobs are at noon that they're flat, but they'd be wrong, most of the time.

There are all kinds of things that are responsible for an amp's voicing, some intentional and some are lucky happenstance (like the venerable Fender tone stack).

Things like eq, filters, the non-linear way some circuits behave when loaded heavily, compression, frequency dependent compression, harmonics generation and their distribution, etc.

 

[lancimouspitt]

Here's a question for everyone .
What is the most transparent head and cab one can buy?

 

[Old Garage-Bander]

I'd hazard a guess that even the instrument cable you use between the bass and the amp, might have a small affect on the sound.

 

[Aidenn7]

I'm going to prolly get flack for this simple, but IMO base voicing comes from the Transformer and how it's driven. you say voicing so I also take that to mean eq- but different components can also make eq changes. A Great transformer can make a big difference.

 

[Aidenn7]

Here's a question for everyone .
What is the most transparent head and cab one can buy?

I got a thunderfunk accugroove combo. that's what I call a clean/flat/transparent combo.

 

[Old Garage-Bander]

A Great transformer can make a big difference.

Yup they do indeed.
Even with low level audio, mic or line level. At work we call it "gettin' out the big iron."

 

[beans-on-toast]

Here's a question for everyone .
What is the most transparent head and cab one can buy?

You may think that you want transparent, but there's tone in some character. I'm not talking about distortion, it is about adding rich harmonic content. Neve preamps used in recording studios for example, add a richness. It sounds good. This is what you want in an amp.

 

[Old Garage-Bander]

You may think that you want transparent, but there's tone in some character. I'm not talking about distortion, it is about adding rich harmonic content. Neve preamps used in recording studios for example, add a richness. It sounds good. This is what you want in an amp.

One with a plexiglass case?

 

[Frank77]

Here's a question for everyone .
What is the most transparent head and cab one can buy?

Phil Jones Bass stuff is (at least to me) very transparent. Played through it, my acoustic upright still sounds like an acoustic upright, but louder.

 

[Aidenn7]

Yup they do indeed.
Even with low level audio, mic or line level. At work we call it "gettin' out the big iron."

the B15 is the first example I can think of.