Aguilar 4J-HC: a sort of review
The title says "sort of review" because I don't have anything like the expertise to go around reviewing pickups, but it seems like not many people have these pickups yet and I should share what experience I've had of them.
I put them in a fretless 1973 Jazz, replacing a pair of EMG Selects. The strings are TI Jazz Flats, and I've played it through an SWR Basic Black (characteristic SWR scoop) and a Harmony H420 (Valco-made 35-watt 1x15 combo from the mid-60s).
First impression: There are a lot of tones in these pickups. As expected, there's a "more of everything" character vs. the old EMGs; more highs, more lows, more output, more quack, more growl. They are very responsive to both my touch and the tone control; hit hard, and/or with the tone turned up, they have rather metallic highs---not tinny, indeed rather full and robust-sounding, but definitely metallic---and a sharp attack that could be too much for certain uses. Roll off the tone and play lighter, and the tone warms up quickly; I can get it to be much warmer and bassier than I would ever actually need. As you'd expect, the highs sound more pronounced and "modern" on the SWR---the Harmony amp is mid-heavy and the result is something more like a "vintage" Jazz sound.
The neck pickup solos very well; the bridge is fine through the Harmony, but on the SWR I haven't quite dialled in how to handle its high end yet, and it goes from muddy to bright pretty quickly. It can do plenty of quack, but with a more bright, modern-sounding tone and an attack. I don't think the Jaco sound is in there---that's not a problem for me, and it's possible that someone with better right-hand skills and more experience hunting for that tone could find it.
These pickups *love* harmonics---the second-fret harmonic basically wasn't there with the EMGs ("twack" with a little hint of a note), and it's clear as the proverbial bell with the Aguilars, irrespective of tone settings and all that.
The hum cancellation is as advertised. They aren't dead silent---there's next to no shielding in this bass, and I'm not sure how much of the residual hum is coming from the pickups vs. other sources---but the general hum is drastically less than it was with the EMGs, and has nothing to do with the balance of pickups. (I should note that each pickup has one polepiece that isn't grounded; I triggered a brief thread on this yesterday and concluded that as far as I can tell that shouldn't be a problem, but I guess it could be a hum contributor.)
On the whole I'd characterize the tone as kind of modern, but not excessively so and with a lot of flexibility available. I'm happy.