My first of the three basses with filter preamps is out for delivery, so I thought I'd start out with some of my existing thoughts on multicoils and filter preamps.
Wal bass: I've briefly played a fretted MkII but the majority of my experience was recording with a fretless Mk I. I absolutely loved the sound of that bass. It was boat anchor heavy and the slight v shaped neck to a little bit to get used to, but the sound was fantastic. Powerful, mid focused, and clear. Very horn-like IMO. The studio was willing to sell it, but I couldn't scrape together the money at the time. Now, it'd sell for probably 5-6 times as much. It had a slight grit to it, but not as much as I was expecting. Overall, when set relatively "flat" it had a naturally big, warm sound.
I say "flat" with quotations, because even with both tone knobs fully open the Wal seemed to roll off in the 3-4k range. And the pick attack was seemingly voiced significantly higher than that. So there were always some missing frequencies in the 4-7 k range which helped emphasize the mid focus of the bass.
Just for reference, I like Tool, but Justin Chancellor's sound has never been "the Wal tone" to me. My favorite has always been Flea on Blood Sugar Sex Magik, but I'm also a fan of Power Windows era Geddy, Bruce Thomas with Elvis Costello, Mick Karn, and Kristian Dunn from El Ten Eleven, who sounded massive with his Wal when I saw them live.
The ACG/East EQ02
The first bass I played with a filter preamp was my old Stambaugh fretless which had EMG Jazz pickups and an ACG/East EQ02. It's on the left here:
That preamp had volume, blend, a high pass filter and a single low pass filter for both pickups with a control for resonance/overshoot peak.
This bass sounded amazing and the filter preamp was a huge part of that. It really let me dial in a deep, mid focused tone with some boost and then let in some highs to balance the sound. I still miss that bass.
The ACG/East EQ02 and ACG Multicoils
I loved the ACG EQ02 so much that it led me to getting a full ACG bass from Alan and then later a second one. The first was a multiscale 6 string that was a bit of an experiment for Alan and me. It had the ACG FB pickups and the 5 knob EQ03 with an added tone knob. It also looked amazing with flamed redwood top & back, a sycamore fingerboard, 7 piece (I think) neck etc. I unfortunately don't have any photos (they were in my long defunct Photobucket account) but it was a superbly crafted bass.
That bass was phenomenal. Rich, clear, and really piano like. It was hi-fi in the best sense of the term. The EQ03 was incredibly versatile. One low pass filter and resonance stack per pickup, a Treble stack with a HPF and gain control, a passive tone, and the bass stacks could even be pulled up for low mid and high mid boosts. It is a clean, clear and super flexible preamp that could create a HUGE range of tones.
In fact, the only issue I had with this preamp was that it was maybe TOO versatile. Even with the 41 detents on the LPF stacks it was very hard to quickly replicate amazing tones that I'd discover. Between the LPFs & resonance, Treble stack, passive tone and switchable mid boosts you could tweak for hours finding (and often losing) great sounds. Which is why Alan worked with John East on the DFM pre which keeps all the good stuff but limits the range of the LPF sweep to make it (I assume) easier to dial in.
After that ACG, Alan introduced his MC (Multicoil) pickups. Looking for more of a Wal tone, I had to have one. So I ordered a singlecut Finn 5. Here's
the build thread for that bass. Neither the EQ03 nor the MC pickups were really an attempt to copy the Wal tone and I think Alan would say that himself. But customers kept asking for Multicoil pickups and so they were created through collaboration (like the other ACG pickups) with Aaron Armstrong. IIRC, the bridge has ceramic magnets and the neck alnico (or vice versa?) and the bridge pickup is given a bit more resonance via the electronics to make it more "bridge" sounding.
@Skelf can correct me where I'm wrong, and I'm sure I am somewhere.
The pickups and filter preamp put that bass roughly in the same ballpark as a Wal, but it is really it's own thing. Less gritty and aggressive, more clean/refined and percussive. To get closer to a Wal you have to close the filters a fair amount because the ACG's filter have more Treble extension when fully open.
It was an awesome bass, and Alan is incredible to work with. I highly recommend him. For my tastes, I actually preferred the FB pickups. I believe they are sidewinder pickups where each coil uses the same blade to create a narrow aperture and make them more single coil like. Set flat the MC pickups had more "character" but the FBs (at least to me) were more of a blank canvas that allowed a HUGE range of sounds while the MCs felt like the filters were making tweaks to a baked in (but very cool) sound.
Assuming my bass shows up as scheduled today, I'll experiment with it and give my initial thoughts on how the Underhill preamp compares to the Wall and ACG and how the Turner multicoils compare to the Wal and ACG MC pickups.
Cheers.