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Nemphasis O2 and Pro Oxygen series pre-amps

Issue #39

So new they hadn't even been announced when we received our review samples, Italian MI audio specialist Nemphasis has two new bass pre-amps. 

At the time of reviewing, these two pedals are so new they haven’t even made it to the Nemphasis website yet. In fact - and I am feeling rather lucky right now, thank you Nemphasis - I am the only reviewer in the world to have had my paws on these two delightful boxes of joy - way ahead of their expected release date. To which all I can say is that it's a great shame for everyone bar me!

So it's into the Guitar Interactive studios and down to our dungeon of low end, with these two superb pedals - both from Nemphasis, Italian boutique creators of guitar and bass guitar effects pedals. The Pro Series O2 Oxygen Bass pre-amplifier and in a downsized shell, the O2 Oxygen Pr-amplifier.

Both are practically the same in terms of control set, which is, arranged neatly across the front fascia: input gain, output volume and a three band active EQ providing cut and boost to centre frequencies for bass, middle and treble. On the smaller of the two boxes, here in a rather fetching blue, there is an included toggle switch, which either boosts or scoops preset mid frequencies. I’m afraid I don’t have the exact frequency centres to share, but in the video, I demonstrate the function working on the Pro Series pedal, which has a dedicated foot switch instead of a mini toggle. I think this is a big win for me, as the voicing of the two settings is absolutely superb! For live use it’s so handy to be able to switch to a solo sound or a ‘present’ tone that will cut through the mix for a melody part, then flick back at the press of a button.

Speaking of the smaller Oxygen pre-amplifier, it's the only one of the pair that can take a 9v battery as well as running from an external power adaptor. The larger Pro Series pre-amplifier pedal however features an XLR D.I output on the top edge of the casing next to the external power jack. A ground/lift switch sits above the level control for the D.I also. I envisage that this pedal would be very useful in the kit bag as a standalone D.I as well as a super sounding active EQ. The smaller O2 Oxygen Bass Preamp has a boost switch under the lid for extra bass should you need it.

OK so sounds - what do we make of these? I plugged my bass directly in and we ran the output straight to DI on my TC Electronic BH800 amplifier set completely flat. I had foldback through some quality stage monitors too. I have to say, as you will note in the video - that the sound from the preamp even with the dials at noon was sublime in the room. Certainly there was a smile inside when I pushed the mode switch too. Not honky, not muffled, just a nice rise in instrument character, without too much low boost.

I like the layout and clean graphics, though be careful with the Pro Series version if you have big ole feet like mine and a penchant for boots. You’ll need to make sure you don’t knock the controls with an overzealous leap on one of the buttons.

Did I need these pedals though? Well, one thing is for sure - my bass has a three band EQ, my amplifier has a four band EQ - the recording kit we have at GI Towers has access to infinite shaping parameters but still, even in writing this review, I am curious to find out what those ‘sweet frequency centres’ were. There was just something really inviting about the tone and clarity of this pedals. For those using kit with limited equalisation, for example, a passive Precision bass running direct to PA (not many of those around - Ho Ho! - Ed) I expect the Oxygen Bass pre-amp will be a very welcome inclusion! I also see this being particularly useful with those who want to run a simple set up or have a great tone going direct to in-ears without going near the back line (particularly useful on gear share gigs!). I believe this pedal would be invaluable in those circumstances. Similarly, being able to drop one of these in a gig bag and fly just with that when you can rent a power amp/cab, or simply DI the bass from the Nemphasis, would make one a must have for travelling musicians.

Rounding up, as you can see from the specification attached to the review, Nemphasis has sourced the very best quality parts for these pedals and I have to say everything is very neat indeed under the covers. We also didn’t detect a single buzz or hiss from out monitoring system either and all controls operated smoothly over their range.

So are they fit for your 'must have' list? Well both Nemphasis Oxygen pre-amplifier pedals, specifically the Pro Series for me, are fantastic at what they set out to do. No, they may not have all the features of other ‘D.I / pre-amp’ devices also on the market, but at the same time, it’s nice to have the option of buying a pre-amplifier with what you need on. Simple, clean and great sounding. You might need to decide which one of these two you would rather have, and that choice will be made depending on the work you do rather than the sound quality, which is identical, but that's no hardship and, also excellent news, both come at very attractive prices! Great stuff, Nemphasis!


Issue #74

Jim Root

Out Now

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