I couldn't find the type of information I was looking for when doing research on the East uni pre amps so I figured it would benifit future buyers to give my findings. The host bass is an Ibanez sr800 with bartolini liscense mk1 pickups. 2 Amps where used. The hartke 3500 and Genz Benz shuttle 6.0 both into ampeg 410 cab. Both amps where set up to be as natural as possible to keep their Sonics out of the equation. Firstly I'll start by giving some details about the stock bass set up. The Bartolini mk1 pickups fed an Ibanez pre with bass, mid , treble, balance and volume. It also had a 3 way selectable mid switch. Overall the bass didnt not sound horrible. I wouldn't say it sounded good either. Adequate comes to mind. It sounded best by far with the tone enhancing controls left alone. The pre was blurry. Transients did not come through with power . The bass control when boosted only made things more muddy. The highs were brittle and harsh. This was particularly bad because the bass in the stock format was on the brighter side of the spectrum. There was always weird harmonics in the mid range, even when the mids where cut. The pickup balance control behaved more like a 3 way switch than a variable knob. Looking at the East pre everything looks and feels of very high quality. The knobs are knurled on the sides. Markings are sharp and clear. All knobs use an Allen head screw to lock down on the pole. I would caution to use adequate force when tightening. If the screw were to lose tension I could see them falling off. A drop of blue loctite on the threads should be enough to stop them from ever backing out. They would be attractive on even the most expensive of instruments. I chose the black though silver and gold are also available. The pots are smooth with a very tactile, audible center click. The push/pull knobs share this quality feel. The pots are neither hard nor easy to turn. They give enough resistance to stay put against unintentional movement while still feeling smooth. Moving to the internals, the circuit boards are rather large. Much larger in person than pictures make them seem. Basses with smaller openings may need routing done and new covers made though it did fit into the Ibanez , it would only fit in a very specific layout without cutting into the instrument. The build quality is fantastic. The preamp comes fully wired in a harness with detachable connectors. This makes wiring a breeze. No soldering required. The battery connector is hard plastic and rather tall. Too tall to fit into the stock battery compartment. For this reason I chose to use the stock battery connector though I wish I could have used the East. It is easy to connect and more importantly, discount ,batteries to it. It does not flex and snaps on and off perfectly. On the circurt boards there are jumpers. Most people will have to remove the pots to change these. The jumpers can change the bass knob from boost cut to boost only. The mid jumper can turn off the sweepable midrange. The last jumper can give a boost in the bass and treble frequencies. I chose to leave it in the flat position. There are 3 internal rotary dials. 2 affect the bass eq knob. You can choose what bass frequencies your knob affects. The first adjust the lower bass. You can chose between 20 and 80hz on the low side and 40 to 200hz on the high side. This allows something similar to a parametric eq with the use of a single bass knob. You can really get specific about what bass frequencies you boost or cut. The 3rd dial adjust the treble side. You can choose your high frequency shelf point from 1kz to 7.5khz. This can push your treble knob down into upper mid territory giving even more control of the crucial midrange or go higher and add sparkle and clarity. Lastly we have 2 pickup input gain controls ranging from 0db to -12db. On the outside we have volume , a stacked bass and treble with a pull to add 8 db of treble at 10khz , active/passive push pull and tone control, a fully active balance and a stacked mid with a sweepable midrange control. On to sound. The stock bass was rather bright sounding but it turned out it was the stock pre causing it. The East pre Sounds smooth and warm in comparison. The passive /active switch makes almost zero difference when the active settings are set to flat. There is no readily detectable change in frequency or volume. The tone control behaves as expected. The active balance is surprisingly good. It sounds smooth when passing off the pickups inputs from one to the other. All positions are usable without the weird harmonics of the stock pre's balance control. The bass control gives a heavy thump on the attack. Where the Ibanez pre would get muddy when boosted, the East pre only gives more and more punch as you dial the bass up. The entire boost range is usable. It's quite incredible the amount of chest thumping power that can be dialed in. The treble in the flat position is subdued a little. I believe this is due to the bartolini mk1 pickups. The 10khz boost on the pull switch counteracts this giving the bass a bit more of a hi fi sound. It does have a a slight hiss when heavily boosted but that's to be expected of an active onboard eq. It does have a ton on usable range before the his becomes apparent. The 10khz boost hiss is almost inaudible at volume. The mid control being so variable let's you dail in just about any tone you can dream up and at no point does the sound break down. Where the Ibanez would sound muddy and distorted, the East keeps it cool and just keeps putting out that thunderous punch. To add to the exteme adjustability, the tone control remains available for use in passive and active mode. My preferred method as of writing this is to use the uni's many controls to get the bass sounding balanced and fat, pushing more towards a hi fi sound and use the tone control to back it off to a more round vintage sound as needed. I cant really give a comparison as to what it sounds like. The East pre is simply just too versital. If you are suffering from unwanted overtones or natural characteristics of your instrument you dont care for, the East pre can certainly isolate and destroy them. Overall the East uni is a fantastic, extremely high quality piece of gear. Mr East is very pleasant to deal with and easy to get in touch with. Due to its versatility I would recommend this pre to just about anyone for any bass. There may be occasions where it delivers too much punch for certain types of music. If chest thumping punch is what you are after, the uni delivers in spades regardless of what type of tone you dial in. Its rather expensive for a pre, but with so many options it would be almost impossible to not be able to dial in a fat, hard hitting tone you wouldn't be happy with, and there is nothing about it that doesn't scream quality. I am anxious to try it with the Nordstrand dual coils. I feel like the Bartolini mk1's may be holding it back some. They are a little dark. While the East can lift that veil from the Bartolinis, I am eager to explore the possibilities of the Nords with the capability of being wired in series, parallel and single coil. The East pres ability to dial in on mid range and treble frequencies promises to open a world of options and tones. I look forward to installing the Nordstands and will be revisiting this thread with my thoughts. Bottom line, if you've got the coin and you are looking for more out of your preamp, the East Uni definitely deserves your consideration.