“Old School Bang Without Breaking the Bank”

As a self-proclaimed “old rocker”, Jim Frenzel  has had a love affair with vintage tube amps since the ‘50’s.  After building his first tube amp in 1952 Jim’s passions grew for building amps but his career path in the music industry wouldn’t rear its ugly head until much later. For the next five decades Jim found himself designing tube and solid state equipment for the various branches of the military, FAA, and even Texas Instruments. It wasn’t until 2001 after his retirement that he returned to building and designing his beloved tube amps. He has been building quality tube products at a bargain price ever since.

Frenzel’s design concept and philosophy is pretty straight forward. He is dedicated to manufacturing quality amps that can easily dial up “tones you know” while still allowing plenty of room for customization. His other passion is making sure he can do this while offering a ridiculously low price for the end user. One of the finest examples of this is the FM-DP1 Tube Preamp.

The FM-DP1 Tube Preamp is a dual channel dedicated guitar preamp for stage and studio use. The FM-DP1 is part of Frenzel’s “Inspired” line and is designed to give you the classic tones of their Type F and Type M wiring. These are inspired by vintage Fender and Marshall style amps with some of Frenzel’s own special modifications that he has honed over fifty years of designs.

The preamp uses two 12AX7s with DC on the filaments to help control noise. The first 12AX7 is wired as a dual input preamp. These are for the Type F and Type M channels of the FM-DP1. Each channel is then controlled by individual gain controls. The second 12AX7 is wired as a common voltage type amplifier with a cathode follower to drive the tone stack.  The three band tone stack features individual knobs for bass, mid, and treble with an optional push/pull Deep Bass Boost pull switch on the bass knob to capture more of a classic Bassman vibe. Add in a master gain knob and you have the basics for a very useable workhorse preamp.

The FM-DP1 is much like all of Frenzel’s products in that it is hand wired point-to-point with no printed circuit boards. This is a feature that is most commonly seen in higher priced boutique amps and is a surprising addition to this little guy. Other cool design features are a trim knob on the rear panel for setting output gains. Another neat spec is that the signal goes into the FM-DP1 as high impedance and comes out as low impedance. This makes the preamp useable as an effect so that you can use it as an extra gain stage or to overdrive an amp. This also proves useful for studio enthusiasts so that you can use the FM-DP1 as a front end to your recording rig.

For testing purposes the Frenzel was used extensively on a number of demo sessions and a handful of live dates. Initially it was plugged into the power amp section of a 40-watt open backed combo amp driving a Celestion Vintage 30. With a solid bodied single coil guitar plugged into the Type F or “Fender” input the tone was instantly what Frenzel had referred to as a “tone you know”. This was the classic Bassman-esque vibe that one would expect from a classic amp of this design. The overall warmth made notes full with just the right amount of midrange snap. The top end of the treble knob was pleasant but not overbearing. Some players looking for a real chimey tone may need to crank the Frenzel’s treble knob though to get that extra bite out of the Type F channel. Luckily it does not get much hiss when cranked so there aren’t a lot of worries in cranking it up the treble for some extra presence.

Jazz players and bass players should take notice of the optional Deep Bass Boost switch that can be added as a push/pull knob on the bass control. In the Type F channel this helps the Frenzel to morph into a full figured rig with lots of bottom end. Hollow bodied guitars sound thunderous in the neck position and basses capture that old school bass tone that is still used in numerous applications. Considering there is no extra charge for this upgrade it is a no-brainer to get this added goodie.

The multiple personality of the FM-DP1 is made complete with the addition of the Type M or ‘Marshall” channel.  While plugged into this input, the EQ section and voicing of the Frenzel takes on a whole new personality. Mids and highs now shimmer and the gain control helps you push the Frenzel to some searing rock tones worthy of any stage. Humbucker loaded solid bodies in particular took on the mass and girth that one would hope for from anything inspired by such a classic style amp.

Overall there are very little gripes with the Frenzel FM-DP1. The preamp is built well for the money. Granted you may fine beefier units out there that you can drive a bus over but the FM-DP1 can still hold up to steady use. This is also a unit stripped down to the bare essentials. There are no flashy graphics and the basic unit is an open chassis design so that you can either use it as a table top unit or put it into your own custom cabinet. Players looking for heartier models can opt for the optional steel cage or rackmount cabinet. One gripe though is the fact that there is not an LED showing if you are powered up or not. It is understood that this is a stripped down unit but it is pretty easy to forget that the unit is on and walk away. An addition of a power LED would be quite helpful but it is by all means not a deal breaker for the value of this preamp.

All in all it is hard to believe that you can dial up the sounds of two classic sounding amps in a hand-wired preamp for the same cost as some boutique pedals. The FM-DP1 can easily hold up on big stages with products four times its cost. Too cool considering you can have some money left for a burger and that whole rent thing.  - Sean O'Bryan Smith (Reviewer for Vintage Guitar Magazine)

PLEASE NOTE: 2/13/10 UPGRADE - Per Sean's request, we have added the LED power light and the Bass Deep pull-switch to the F gain control as standard features on all future models. We have also added a Bright pull-switch to the M gain control. Best regards,  Jim Frenzel