Why use an external preamp when amplifier has 5 band EQ?

Jul 8, 2024
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I play bass just for fun. Recently, I have been considering an external preamps such as a Sadowsky SBP2 or an Aguilar AG for my passive Fender Jazz. The reviews say it give 'better' tone. But my bass combo has a 5 band EQ section. Assuming, i am not looking for a second sound whilst playing (soloing or overdrive), would I really need a pedal EQ to shape the tone? Any clear benefits of using a pedal preamp? Thanks!
 
I play bass just for fun. Recently, I have been considering an external preamps such as a Sadowsky SBP2 or an Aguilar AG for my passive Fender Jazz. The reviews say it give 'better' tone. But my bass combo has a 5 band EQ section. Assuming, i am not looking for a second sound whilst playing (soloing or overdrive), would I really need a pedal EQ to shape the tone? Any clear benefits of using a pedal preamp? Thanks!
You don't need one.
 
The reviews say it give 'better' tone.
What’s better for me is not necessarily better for you.

Tone is more than just what the eq provides. There might be drive, compression, and other options that provide more flexibility. The bass and amp you use might sound different than what the reviewers play.

Try it first and see if it helps. It might not. Then again it might. Nobody can say for sure.
 
You don’t need one.

However, you should know that not all EQ circuits do the same thing so they can sound very different. EQs with more bands, boost and cut, sweepable midrange, etc. are more flexible on paper but the player has to work harder to come close to what the Sadowsky does with just two “more” knobs.

The Sadowsky preamp in particular is what most people call “musical”, it just makes the instrument sound better. It’s just bass and treble but the bass band extends pretty high in frequency and the treble gets pretty low. It’s also boost only. If you crank both bands all the way what you end up with is a severely scooped midrange, which is popular with slappers. With small amounts of boost it fattens out the lows in a very pleasing way. The treble boost is useful if you don't like cabs with tweeters but want a bit more high end. The pedal uses the same circuit found in Sadowsky basses so it sounds the same without requiring non-reversible surgery on your bass.

BTW the Sadowsky preamp was designed by Alex Aguilar many years before he got involved in making amps. The DB 925 preamp pedal is very similar in design to what he did for Sadowsky, at least based on the specifications. It is literally their OBP-1 preamp circuit in a box. The AG preamp has way more features than just it’s four band boost/cut EQ and “bright” and “deep” boost switches…it’s also a headphone amp and a DI box as well.
 
The short of it is: playing in different rooms/venues/ scenario/circumstances will sometimes require you to carve out a different sonic footprint for your instrument to sit where you want it. Real-time mixing. When you're in a scenario and the cymbals are occupying a certain high frequency or the keys, guitars, samples, etc are sitting in a certain range then the extra EQ can come in handy.

Different EQ designs will give different options of sweeping certain ranges, so a DBX eq might differ from a Gallien EQ, from a Mesa EQ and so on. Hopefully. It's not always necessary but it answers the questions of why.

As I've found myself in different playing scenarios, I've become entranced without how different the sweeping of mid frequencies can alter a tone to fit what you're looking for. Like going from a Duff McKegan tone to a Dub tone for example. It's all fun to carve out sounds and learn along the way.
 
1. The preamp in question gives you "that" tone. Should your amp have a strong flavor and is not really able to give you a transparent tone. For example, you have an amp that has very crystal clear treble and a certain harshness to the tone, but you want to go towards something warm and round, then you could get a preamp that gives you warm and round and bypass the amps preamp section.

2. You're playing live a lot and want to send a processed signal to FOH, but need the amp EQ to set your stage tone.
 
Oh man … looks like I may have to lug my bass and little combo to the shop and try them preamp pedals out. Then it may not sound the same as in the shop as when I’m back home! :laugh:

My combo is the Ashdown C112-300. It’s kinda neutral/transparent save for the ‘shape’ function. When engaged, it’s actually in bypass mode. Guess Ashdown wants us to enjoy their ‘warm’ house sound first.

I do like the EQ on my Ashdown. It does the job but I’m getting influenced by YT reviews.

I’m definitely gonna try out compression and an overdrive (for just a smidge of grit).

Thanks a lot for all the feedback. Gives me more things to consider. 🙏
 
- EQ can be Cut-only or Boost/Cut...even if the knob just says "Bass" or "Mids"
- Frequency bands and ranges are different on various EQ tone stacks
- Preamps often incorporate different gain, compression, and other characteristics that aren't always labeled on the pedal
- Buffered preamp pedals can help with long cable runs to the amp's front end, reducing attenuation on your bass signal

Some pedals do fine going into an amp's front end, while others sound better going into the Effects Return or a power amp. If nothing else, having a second EQ setting you can turn on with a footswitch is helpful. The added gain can also help make up for basses with weaker signal.

There's plenty of reasons to get one, you just have to ask yourself if any of them are worthwhile to you. Also not a bad tool to have if a gig doesn't allow for amps on stage.
 
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1. The preamp in question gives you "that" tone. Should your amp have a strong flavor and is not really able to give you a transparent tone. For example, you have an amp that has very crystal clear treble and a certain harshness to the tone, but you want to go towards something warm and round, then you could get a preamp that gives you warm and round and bypass the amps preamp section.

2. You're playing live a lot and want to send a processed signal to FOH, but need the amp EQ to set your stage tone.

The second point is the main reason I use one. Most sound engineers like a direct signal that is sent before the EQ on your amp, so in other words, there is no EQ being sent to the main speakers. IF you want any flavor at all to be part of your live sound, you're going to want a preamp in this case. It's part of why "amp in a box" pedals like Tech 21, Darglass, etc. are so popular.

Also, my gigging amp is a clean, solid state amp. I like adding a bit of vintage warmth and overdrive to the front end. Right now I'm using a Sushi Box Slampegg on my pedal board, which emulates the sound of a vintage B15.

In the end it's about using your ears, and what you like the sound of. As with many of these things, "if you have to ask the question, you probably don't need it".
 
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I’d rather have active tone controls on the bass, fiddling with knobs on a pedal is even less accessible than ones on an amp mid song. It’s an older design, but the preamp in my G&L L2k gives me all the tone shaping I need. There are some pedals with added features like overdrive and DI that are useful. I used to use a pedal with WQ sliders, but left it on the amp, not on the floor.
 
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I use a separate preamp DI pedal to shape my tone going to the PA, just for the audience. I use the eq on my amp after that (sparingly) to shape my amp tone on stage just for me. I could just use the eq and DI on my amp, but setting eq for what I hear on stage isn’t always best for the PA. If I don’t gig with my bass running through a PA, I don’t really need the extra preamp.
 
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Summary of the above: if you're happy you don't need a preamp, but you might want one, in order to:
  • Toggle a second tone, e.g. scoop for slap as mentioned above
  • Add tonal tweakability not provided by your amp EQ, e.g. sweep mid
  • Add a little extra sumthin' sumthin', such as harmonic richness from tube(s)
  • Add utility features such as HPF, cab sim, tuner, DI out
FWIW: I've owned a variety of clean preamps then and now for the above reasons, but the majority of the time I only use a "preamp" pedal as an overdrive/distortion effect. OD pedals are often called preamps if they also provide versatile EQ (i.e. more than a single tone control), DI out, and perhaps other features. I didn't mention this above because I assumed FX were off topic.

Note: as mentioned in the previous post, DI out from a pedal can be useful at the gig, especially if your amp doesn't have a pre-post switch for its DI. That way, you can DI to FOH from the pedal, and tweak your amp EQ at will without worrying about pissing off the sound tech.
 
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