Presys Blend 301 Acoustic EQ Equalizer Guitar Preamp Piezo Pickup Tuner by AdvancedShop

Quality and price. Great preamp with mic and piezo. Fishman pickups are known for their high quality and value for acoustic instruments. Best bang for the buck.

Okay. I bout this and another brand that is competing with this one. I installed them both in two different guitars. This one certainly is worth the china price I paid for it, but the other was the same price and much better quality. This one has a cheesy flimsy battery compartment that holds a 9v battery by force of friction only. Sooner or later, the friction is going to wear away and then the battery will start to lose its connection. I had to disassemble the device in order to make a template. I learned afterwards that the manufacturer has the templates on their website. User guide was worthless, maybe it's a knockoff...I don't know. One thing I did like is the screw retainers. These retainers are absolutely necessary because the screws do not have enough wood to hold long term. On the other amp, I had to fabricate a retainer out of balsa wood.Buttons are not aligned perfectly in their holes. But that could be a result of me taking it apart to make a template, although I doubt it. It is small if you prefer small. The other one was larger.There is zero curvature on this amp. The lack of curvature severely limits where and how you can install it. I found that it could only be installed perpendicular to the top and bottom. This sort of install required modifying the kerfing with a dremel conical grinder. BTW I used a dremel to cut the hole. Dremel makes a router bit at Lowes for like 3.99. Worked very well but be careful because it will route very quickly and can easily cut more than you wanted.Faceplate is only 1/16" larger than the hole. You know what that means right? NO ROOM FOR ERRORS IN THE CUT. Small faceplate is my BIGGEST complaint. I can't understand why they insist on a tiny faceplate.The jack install was horrible, absolutely horrible. You are expected to place a retaining nut inside the guitar without any tools. Due to a large connector on the end of the jack wire that connects to the preamp, you cannot even use a handheld deep socket to slip over the wire. But that wouldnt even have made a difference because the jack nut is slightly thicker than a piece of paper. A much larger nut would have made my life easier. Fortunately, I had long thin arms with long fingers. After 30 minutes of effort, I finally got the nut started. But tightening was basically impossible. IT IS IMPERATIVE THAT THE HOLE FOR THE JACK BE SLIGHTLY SMALLER THAN THE JACK. With a smaller hole you can thread the jack in the hole very snuggly. FYI , you can unscrew the jack strap button to reveal an external jack nut.This is a very poor design and really needs to be totally redesigned. I can't comment on the circuitry but if it is anything like the casing then I would not recommend this at any price.Time to install was about 4-5 hours.