I have heard one. The local high-end dealer here is a dealer for ADK.

The idea is sterling. The pres are very very good.

It looks like ADK is doing some very logical things that are going to set new trends. This is so cool.

What do you do Dave? Load cards into it?

I'm resurrecting this thread, as I've had a chance to use this preamp recently.

A friend of mine is remodeling his house, and decided to tear down his studio during the remodeling process, and he has lent me his ADK AP-1 for a few months.

The AP-1 (single channel) and AP-2 (2 channel) were made by ADK for a few years, with a neat feature called "pop and swap", which allows the user to swap out both Input Transformers and Op Amps without the need for a soldering iron or, even any tools. You simply pull up the existing ones, choose another, line up the prongs on the transformer or the OpAmp to the daughter board, and plug them in. (Of course, you should pwer the unit down first. I even go so far as to unplug the unit and wait 30 seconds or so before making the change-outs.)

ADK no longer makes these, or any mic preamps. Apparently, the markup on them wasn't enough for the company to turn enough of a profit to continue them. They have gone back to making microphones only.

My friend included several different input transformers, as well as several different op amps with the AP-1.

These include:

Inputs:
Stock ADK (Crimson)
Cinemag
Jensen JT110
Sowter 9820
Lundahl 1538

OP Amps:
John Hardy 990C
Seventh Circle SC25
Cinemag
ADK Vint OP / API 2520 clone

The AP-1 itself is a bare bones, no frills pre, with a rotary gain that goes from 25db to 65 db. There is also an impedance switch, located on the front, that when engaged, adds resistance that is useful when using certain dynamic or ribbon mics.
A single 1/4" instrument jack, 48v Phantom, -20db pad and phase reversal buttons round out the front. On the rear is an XLR in, an XLR out, power switch and power cable port (takes a standard 3 prong computer-type power cable). The overall build appears to be top notch. All internal components look to be carefully chosen and hand wired and installed. At full gain, the pre is whisper quiet. Absolutely no noise from the unit at all.

The front graphics are a little cheesy looking, but I understand that this was kind of an experiment for ADK, and they were trying to keep cosmetic costs down, and instead putting the money into the things that actually mattered - like the build and quality. Personally speaking, I don't care what a piece of gear looks like - my first criteria is always that it performs and sounds good... and IMHO, this preamp does.

I've not yet had the chance to try all the transformers or Op Amps. Of course, I will... I just haven't yet. So far, using an AKG 414EB as my mic, I really like the Jensen/John Hardy 990 combination the best. Just shy of totally transparent, with a touch of mid-range presence, and smooth high's. The low end seems well defined. I haven't yet had a chance to use it on anything other than my own voice and an acoustic, although I really want to try it on bass guitar and other lead vocalists as well. I'm also very interested to hear what it can do with kick and snare.

Anyway, just thought I would share. As I do more with it, I'd be happy to post my thoughts (and samples) using other combinations. ;)

d.