The SCR-DI does an incredible job of emulating that classic sound you get from a big old school Ampeg SVT rig. With its tuned 3 band EQ, it’s less focussed on the Mid sound – it’s all about low and top-end here.
This is possibly still the best clean preamp pedal on the market for the price. The MXR M81 is an absolute must for those looking to shape their tone before hitting any other effects.
The much-heralded Tech 21 SansAmp. You don’t need to be a French-language expert to work out that this was designed to be more than just a pre-amp. This was supposed to replace your need for an amp completely!
The Aguilar Tone Hammer is a clever piece of kit. A pedal that can run as an overdrive and active EQ whilst having the capabilities to perform as a pre amp. Impressive D.I. gives complete confidence for the studio or the stage.
This pedal is really suited to the master bass enthusiast. If there’s a particular tone you want from your bass, it’s pretty safe to say you‘ll be getting very close with the options you have onboard.
Who would love this? Home users, gigging bassists who love the big Ampeg sound, players who want a serious treble scoop to their tone
This is one of the newer kids on the block compared to the MXR and SansAmp, having only been released in 2015.
This is an interesting piece of kit, as it comes from one of the most prestigious traditional amp manufacturers in the world. The good folks at Ampeg, whose ‘endorsed artist list’ reads like a who’s-who of influential players.
In true Ampeg style, it’s a heavy unit and somewhat bigger than a lot of other pedals. A heavy sound is exactly what you’ll be receiving.
The SCR-DI does an incredible job of emulating that classic sound you get from a big old school Ampeg SVT rig. With its tuned 3 band EQ, it’s less focussed on the Mid sound – it’s all about low and top-end here.
I got an extreme amount of top-end tone as well as a *massive* low-end sound by using the Ultra High/Lo shift switches.
In addition to providing that classic tone (which I really love) are a number of other killer features. Firstly, you can plug an external audio device into it and play along with that, or even plug a mic into it! This is a gamechanger for anyone wanting to rehearse at home. The SCR-DI also provides a standard 3.5mm headphone jack out, hearing everything from your iPod and your bass in perfect harmony.
The final cherry on this Ampeg-flavoured cake is the ‘Scrambler’ circuit. This feature gives the player an overdrive pedal in the same box. The ‘Scrambler’ is available as a separate pedal. So think of it as an almost-free addition to the package.
A big plus is that the Scrambler is footswitch operable. So unlike a lot of other pre-amp pedals, you don’t have to physically bend over and turn your drive dial back if you want to drop the drive tone!
It’s a competent overdrive. My testing of it showed that it performed best by adding a little bit of fuzzy breakup to your sound. Think of that slightly overdriven 60’s sound – rather than a Muse-esque full fat filtered OD.
I really love this pedal, and can’t live without it now because of the sheer amount of options it provides to the player. Particularly the ability to practice at home without annoying the neighbors or your partner!
My one gripe would be that the power supply connection at the back seems a little loose. Maybe that was just my review unit – it’s probably simple to open the back and secure it a little better inside the case.
Dimensions: 4.3 x 7.6 x 2 inches
Pros
The Aux-in feature combined with a headphones output is fantastic for practicing at home
Separate switch-operated Scrambler overdrive section
Replicates the classic “big Ampeg sound” like no other pedal
Who would love this? – Bassists looking for a second tone to use alongside an amp, using as a boost, or a simple way to DI their signal to a PA system
This is the cheapest of the options we tried out, but don’t let the cheapness make you presume this is a “budget” pre. It’s made by MXR (aka Jim Dunlop of wah-wah pedal fame) who make very robust pedals – this isn’t going to break, ever!
Dimensionally this is a small piece of kit, so won’t take up much real estate on your pedalboard, which some may find a positive.
It is lacking some of the features seen on the other pedals. But the fact they’ve still managed to push an excellent 3 band rotary EQ into such a small package, probably means they didn’t have a lot of space for other stuff!
Generally, I found this pedal to be quite “middle-y” in the sound department. There’s even a mid sweep control so you can really dial in a precise middle frequency. So if you are after that kind of all-round full sound, then this is a good option.
I was also impressed with the balanced XLR out which provided a clear signal to an external desk.
The MX M81 offers a sweet sparkle and a warmth that no other pedal can around this price category.
If you’re looking for grit or an aggressive tone to add to your sound then this isn’t for you. This is possibly still the best clean preamp pedal on the market for the price. The MXR M81 is an absolute must for those looking to shape their tone before hitting any other effects.
These MXR guys really nailed it with this little beauty. There’s a reason why it’s still selling well after 10 years +
Who would love this? – Bassists considering going “ampless” completely, anyone looking for an all-round great mid tone
Ah, the much-heralded Tech 21 SansAmp. You don’t need to be a French-language expert to work out that this was designed to be more than just a pre-amp. This was supposed to replace your need for an amp completely!
Presented in a solid built black box this unit does all you could possibly want from a pre-amp. You have the same 3-band EQ that we saw on the MXR, but this time you’ve got some extra features to play with, and they all work superbly to augment your sound.
Tech 21 has included a tube emulation circuit to work as an overdrive channel. So, if you’re a player who likes to get his fuzz on, you can’t go wrong with this.
The more seasoned user will find the various pad options extremely useful. Especially when working with basses with “hot” signals to ensure a clean signal to an amp or FOH setup.
I also was a big fan of the Shift controls on this unit. It gives you the ability to really give your sound a massive low boost, and a sizable mid boost – or both!
The other trick up its sleeve I really liked, was the addition of phantom power. This means you can power the unit from a desk without a power supply or battery. A nice option to have if you intend on truly going “sans-amp”!
I especially liked the added feature of bright yellow markings on the unit. Makes it easy to find dials and buttons in a low light gig situation.
The one thing I’d add would be a treble shift as well for the full set.
We can confidently recommend the Tech 21 SansAmp to any player in any style – Geddy Lee is a known fan of Tech 21 preamps, and that man knows how to get a tone!
Dimensions: 1.97 x 4.72 x 3.74 inches
Pros
Impressive fuzz tone
Shift controls capture the low B string of a 5/6 string bass perfectly
Who would love this? The Riffmeister. The gain controls on the Tone Hammer left me begging for buttermilk. Boutique Beauty.
The Aguilar Tone Hammer is a clever piece of kit. The thing that struck me initially was it runs as overdrive and active EQ whilst having the capabilities to perform as a pre amp. Impressive D.I. gives complete confidence for the studio or the stage.
The amount of depth and clarity is apparent when you first get a taste of this beast. The tone-shaping abilities are right up there with the best.
The AGS (Adaptive Gain Shaping circuitry) feature gives the user a number of possibilities to create some gritty aggressive driven tones.
I’m not overstruck by the look of the box, the controls are thrown into the middle of the board. For the price I would have expected more, but who cares what it looks like. It’s as strong as an Ox and had me gnashing my teeth when I sampled the chunky fat gain tone. For this reason, I want one just to get unnecessarily aggressive on my P-Bass!
If you’re like me, you want silky riffs, get yourself A Tone Hammer!
Dimensions: 5.37 x 4.5 x 2.62 inches
Powered by 2x 9v batteries
Pros
AGS Circuitry
Unbalanced output can drive a power amp
Can happily do mild fuzz to aggressive fuzz tones without losing clarity or bottom end
Cons
Cannot switch between clean and distorted sounds
2x 9V batteries or an 18V PSU is not ideal when the standard is 9V
Who would love this? The Connoisseur. A Bassist with the time and patience to master the superb onboard ‘Virtual Cabinet’.
Dark Glass Electronic have again improved their popular range of professional standard Pre amp pedals.
First, we loved the B3K Bass overdrive, then came the B7K with its impressive 4-band EQ. Now they’ve gone a step further and produced the outstanding B7K ULTRA.
The ‘Ultra’ now has a second footswitch that gives you the power to whack the drive and pre amp circuits in and out individually.
This is a big feature upgrade giving the player even more flexibility than ever before. You are now presented with the option to finely tune your Low to Mid and Low to High EQ.
With 8 Knobs and 4 toggle switches in total, this pedal is really suited to the master bass enthusiast. If there’s a particular tone you want from your bass, it’s pretty safe to say you‘ll be getting very close with the options you have onboard.
The 2 Toggle switches between the MID bands represent different frequencies (Low Mids: 250 Hz, 500 Hz, and 1 kHz and High Mids: 750 Hz, 1.5 kHz, and 3 kHz). The other 2 toggles deal with the drive options. If you’ve been lucky enough to own the earlier models you’ll be fully aware of the quality of these options.
The ATTACK toggle deals mainly with the high-end signal, the 3 options are Flat/Boost or Cut.
The GRUNT Toggle to the right is the same in essence but deals with your low end of the overdrive signal. These are very nice options to have!
From left to right the main EQ knobs are pretty self-explanatory, yet give you furthermore tones and hours of play to enjoy. Output: Master/Blend (Top) Bass/Low Mids (Bottom). Input: Level/Drive (Top) High Mids/Treble (Bottom). The two-foot switches are Distortion and Bypass. When they are both engaged, you’ll get EQ and Distortion. Nice!
I would recommend this pedal to anyone wanting to really get into the art of dialing in. If you’re looking for specific tones and wanting to get as close as possible to that tube drive sound.
A pre-amp can play many roles for a bassist and is always a handy thing to have in your arsenal. You’ll generally find a use for it in most situations!
The name gives it away – a ‘Pre Amp’ lets you sculpt the sound you want *before* your amp pushes it out of your speakers. That includes before your amp EQ gets hold of the signal if you are using yours with a standalone amplifier.
Generally, most players use one to dial in the sound of a particular amp or to replace a standard amp and go directly into a FOH (“Front Of House” or “PA”) system. But they have many functions other than this.
The thing is pre-amps, just like standard amps can vary drastically in regards to the number of features and price. So that’s why we’re here to help you find the pre-amp that’s best for you and your bass sound!
What’s The Difference Between a ‘Bass Preamp Pedal’ And An ‘Onboard Bass Preamp?’
A bass pre-amp pedal is exactly that – it’s a pre-amp in a pedal not in an amp.
They are generally quite small and portable. When we talk about onboard preamps, this refers to amplifiers. Amplifiers also contain an onboard pre-amp. So you can modify the sound of the signal you’re sending *before it gets to the main amplifier stage.
This in essence gives you a lot more scope to change the sound to whatever you want. Leaving the power stage of the amplifier to just make it nice and loud for you.
In many cases, you can turn off the pre-amp (or at least set it to a neutral sound curve) and simply use the controls from your main amp if you so choose.
Some amplifiers have the pre-amp set aside completely as a separate circuit to play with. Such as an overdrive channel. Sometimes including actual tubes inside to pre-amplify the signal. These can be very advantageous to a player who uses fuzz regularly in their songs. You can mix the two in together, but also drop the pre-amp section completely when you need to go clean.
How To Choose The Ideal Pedal
There is no magic answer to this. Consider your bass playing situation and tailor your scenario to our pedals above. Within the five pedals we’ve chosen, we’ve factored in:
Brand
Versatility
Controls
Ease Of Use
Lastability
Value For Money
Lower Budget
Reliability
Conclusion: Our Verdict
After many years of using pre amps in many different bass playing scenarios, Steve ‘Stag’ Jones No.1 pick is The Ampeg SCR-DI!
This offering from Ampeg gives you the best bang for the buck in regards to value, general sound quality, and extra features. However ALL of these pedals are not going to let you down – check out pros and cons to make sure you get the pedal that suits you the best.
Reviewer’s Bio :
Steve “Stag” Jones is a semi-professional bass player currently living in Norwich, England, UK. He has played countless live gigs over his 25-year career providing ‘low end love’ to the best local bands and has extensive experience writing and recording bass lines for various artists in the recording studio. Steve holds a National Diploma in Jazz, Popular, and Commercial Music and is a big fan of Rickenbacker bass guitars, paired with TC Electronic and Ampeg amplification.
Fact: Steve was the only human in history to be born with a Rickenbacker bass in hand.
Lee has been playing guitar for over 25 years. In the 1990's he made a few TV appearances in London and supported a few big bands at festivals. He's recently sung on radio and worked as a full-time guitarist/singer. Lee is the founder of Authority Guitar, a site where he wants readers to enjoy every aspect of learning the guitar.
2 thoughts on “Best Bass Pre Amp: An Expert Opinion”
If Beethoven had no limbs and was never able to play an instrument, but still wrote his compositions, he’d be just as legendary.
If Beethoven had no limbs and was never able to play an instrument, but still wrote his compositions, he’d be just as legendary.
You’re not wrong! (: