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Deluxe Plexi 1 Preamp


FM-DP1 Open Chassis Model

  • Model No. FM-DP1-OC

  • Open Chassis Model For DIY Cabinet

  • Dual Channel Deluxe & Plexi Preamps

  • Separate Gains With Bright Switches

  • Deep Bass Switch

  • 3 Band Tone Stack

  • Tubes" 2- 12AX7

MSRP: $533.00



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FM-DP1 Pro Cab Model

  • Model No. FM-DP1-PRO

  • Vented Removeable Cover

  • Dual Channel Deluxe & Plexi Preamps

  • Separate Gains With Bright Switches

  • Deep Bass Switch

  • 3 Band Tone Stack

  • Tubes" 2- 12AX7

MSRP: $533.00



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FM-DP1 Rack Mount Model

  • Model No. FM-DP1RM

  • 2U Rack Mount Chassis

  • Dual Channel Deluxe & Plexi Preamps

  • Separate Gains With Bright Switches

  • Deep Bass Switch

  • 3 Band Tone Stack

  • Tubes: 2 -12AX7

MSRP: $655.00



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The FRENZEL FM - DP1 "Deluxe Plexi" dual channel guitar/bass tube preamp is part of our "INSPIRED" line of products and  will give you the classic vintage tones of our Type F(Fender Deluxe)  and Type M (Marshall Plexi)  tube amps...and much more. This is the same preamp we use in our FM-5E3DP-525 and other similar voiced amps.  As with all of our "INSPIRED" Line of products, this preamp was inspired by the vintage 50's-60's amps with the "TONES YOU KNOW"...but it's far from simply a clone....this preamp incorporates features and mods developed over FRENZEL Tube Amps 65 plus years of building and fine tuning it has many unique upgrade options.

The preamp uses two dual triodes with DC on the filaments for low noise. The first tube is a 12AX7 wired as a dual input preamp…one Type F input for the vintage smooth warm Fender Deluxe type tones and one Type M input for the classic vintage Marshall SLP high-mids rock tones. Each input has separate gain controls for each preamp section. The second tube is a 12AX7 wired as a common voltage amplifier to drive the tone stack with a  cathode follower to provide a common low impedance output. The three band tone stack was designed by the “tube amp God” Leo Fender, so no improvements there, but we did add a Master volume.  With the tone stack and Gain and Master control combination you can get just about any sound you want.....including great clean tones…or the classic tube preamp distortion that the vintage tube amps are famous for. Also, for you Bass and hollow-body guitar players a Deep Bass Boost pull-switch has been added on the Bass control  to give that Bassman 864 contour for those deep bass tones; and a Bright Pull-Switch has been added on the F and  M Gain controls for sparkling Treble tones. There is a Trim control on the rear panel to match the input drive level of the amp you are using it with. added extra… can use an “AB-Y” pedal on the input jacks and blend the Type F  and Type M preamp sections for your own custom sound. The inputs are high impedance and the output is low impedance. This allows the preamp to work as an effects amp between your guitar and the input jack of your amp....or in your amp's  effects loop...or as  a Direct In for recording.  It will also drive studio mixers or PA amps. If  you have never played through a tube preamp.. you are in for a real treat. If you have, you are still in for a trip, because of the combination of Type F smooth warm tones and Type M high-mid overdrive tones and other extras that have been added.  It makes just about any tube amp sound better...and for you guys with solid state amps who are craving that vintage tube sound, you can insert it in front of your solid state amp and get that classic vintage  custom sound of your own. It works great with guitar, bass, keyboard and harp. 

Standard Features:

  • Input Jacks isolated from chassis to eliminate eddy currents and hum.

  • DC on filaments to eliminate 60 hz hum.

  • Star ground system to eliminate induced current chassis noise.

  • Type F (Fender) and Type M (Marshall) inputs with separate preamps and Gain controls for the unique smooth Fender Deluxe rich warm blues tones or the Marshall Plexi SLP dynamic high-mids  tones....or you can use an AB-Y switch and create your own distinct tones.

  • Classic  Plexi - Bassman style 3-BAND TONE STACK with mid-scoop for extended flexibility in shaping your tone.

  • Deep Pull-Switch on Bass

  • Bright Pull-Switch on F and M Gains

  • MASTER level control so you can crank the GAIN's up and overdrive the preamp without overdriving the output tubes.

  • Preamp tubes are classic 12AX7's known for low noise and linearity. You may also use 12AT7's or 12AU7's for different tones and less preamp overdrive.

  • Classic Knobs and Toggle Power Switch

  • Standard IEC plug-in three prong grounded power cord. 

  • Rock solid point-to-point hand wiring using only the best of parts...low noise tubular polypropylenes caps, metal film resistors, Micalex sockets, Neutrik  jacks...etc.

  • Sweet vintage clean to classic overdrive tones with three different types of  distortion depending on whether you are overdriving the preamp, output... or both! ​

Electrical Specifications: 

  • Input Impedance:  1 megohm

  • Level:  Instrument Level (100 millivolts RMS)

  • Output Impedance:  25K ohm

  • Output Level:  Line Level (2.5 volts RMS) 

Physical Data: 

  • Dimensions  -  Open Chassis 10"W x 6"D x 2"H; Pro Audio Cab 11"W X 7"D X 5"H; 2U Rack Mount Chassis 19"W x 10"D x 3.5"H

  • Rock solid point-to-point hand wiring with military style tie-wrapped wiring harnesses for long life and reliability.

  • DC on filaments to eliminate 60 hz hum.

  • Star ground system to eliminate induced current chassis noise.

  • Input and Output Jacks isolated from chassis for low noise, eddy currents, and hum.

  • Classic Vintage Fender Control Knobs

  • Components - Only the highest quality parts are used including heavy duty transformers, low noise tubular polypropylenes capacitors, metal film resistors, Micalex sockets, Neutrik jacks. All parts are rated for commercial high use conditions. Wherever possible we use parts made in the USA.

  • Front Panel Controls - F Input Jack, M Input Jack, F Gain/Bright Pull Switch, M Gain/Bright Pull Switch, Bass/Deep Pull Switch, Middle, Treble, Output Level, Pilot Lamp, On-Off Power Switch

  • Rear Panel Controls -  Power Cord Connector, Fuse, Output  Jack, 

Custom Shop Upgrade Options:

These options allow you to  customize your amp to meet your special individual requirements.

ONE WATT POWER AMP - Add a power amp using a  Class A Single-Ended output stage which will deliver F and M crystal clear cleans or great overdrive tones at 1 watt of power into an 8 ohm speaker. This allows you to use the FM-DP1 as a low power practice amp as well as a preamp. With this option a speaker jack is added to the rear panel. Add $120.00

HIGH GAIN JCM800 PREAMP - Pull switch on M Gain control  changes  both F & M channels to JCM800 type  high-gain lead tones.  Add $95.00​  

6SL7  PREAMP TUBES  -  replaces 12AX7 preamp tubes with vintage 6SL7 "big bottle" tubes for the 40's-50's vintage Les Paul tones. Add $75.00


RETRO CAGE COVER  -  Ventilated cage cover for open chassis model provides protection for tubes and excellent ventilation. Add $115.00



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Video By Featured Artist  David Wolfe

In this video we use a hand wired analog Frenzel FM-DP1 tube guitar preamp in conjunction with a vintage rosewood freetboard fender Stratocaster with hand wound single coil pickups straight into a Focusrite 2i2 digital interface. Using Presonus studio one as our recording software we were able to add the following 2 studio enhancements. first we added the ownhammer 1x12 tweed deluxe impulse response (IR) to the track, this is all that's required to simulate the speaker and microphone model waking the track sound like it's coming from a real amplifier. The next and final step was to load a reverb (room) effect into the track to make it sound like it was recorded in a room. This is a great way to lay down tracks in a home studio during all hours of the night. With this simple piece of gear you can dial in many sounds that don't have the digital fizz that is common in digital amp simulators. These units are hand point to point wired, will last a lifetime and hold their value. You will not be disappointed.

Review By Featured Artist  Tony Clarke

FRENZEL "FM-DP1 PRO" GUITAR PREAMP  - Hello, I bought the FMDP1 to use going straight to PA system, but does not mean I can’t have some fun at home. Driving a Carvin Mach 100 into a 2-12 open/closed TDM cabinet with Mesa branded EVs.  Thanks Tony C. (Arkansas)

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Review By Featured Artist  Luke Sullivant 


Hello Frenzel team! - Just wanted to get you a picture of the FMDP1-800 preamp hanging out in the control room of Nashville's legendary Sound Kitchen studios near their incredible custom API console. This preamp is indeed everything you all describe it to be, and everything I hoped it would be. Even though I didn't personally have an immediate need for another amplifier, my use of impulse response cabinet technology so frequently had me just too curious to not purchase your preamp.... and send it into a "cabinet" via an impulse response cabinet loader. Immediately I noticed that it sounds very very full. Your circuit is gobbling up the guitar signal, and covering it in every bit of tube goodness that I recognize so well from countless hours over the years spent recording via the tried and true method of mic'ing up boutiques and vintage amps. I can't say that I'm surprised, as your reputation was known to me; but one surprise about this standalone preamp, is that when run straight into a 'digital cabinet' (impulse response loader) I did not find myself missing a tube amplifier power section. No need to explain here why the power section of a great tube amplifier is important to us tone-hounds. But, in all honesty, I think the only feature I would miss when running your preamp into a digital scenario is maybe some of the negative feedback/low 'chugging' sounds you get from a dialed in power section + real cab. Solution when I need that sound---> plug this preamp into a great amp's return jack, or standalone power amp. I would actually equate the way that I'm using your preamp to plugging into a great single-ended guitar amp. That is what this sound I'm hearing reminds me of.  Very immediate and connected to your guitar and your playing; gobbles up guitars, pedals, basses, and makes them sound their best. Both the Fender channel, and the Marshall channels are voiced perfectly, no guessing, they do not sound like each other. Very happy and impressed, thanks so much! - Luke Sullivant in Nashville

Review  by Featured Artist Dalibor Jurasin

 Dear Jim, I got your preamp 10 days ago and I done a lot of tests with various guitars archtops, solid bodies,different pickups, few amplifiers and directly to Cubase 5 in my studio and all together it's amazing device and above all my expectations. I was expecting nice crunch and overdrive, but as I'm more clean/jazzy fun I'm impressed with nice warm,sweet clean sounds with tasteful tranzients in all guitar frequencies. Also my Polytones and Evans got some new dimension. Both channels F & M work perfectly and I thought that F will be mine, but I like M even more for some bebop and Wes Mongomery sounds. Together F & M channels connected via Lehle pro splitter are great too. Anyhow I can and I will use your small monster in all situations regardless style and other equipment because he will add some tube juice into my sound. 

The FM-DP1 is run through both Acme cabs and the Peavey power amp. The preamp's controls were set at T: 2, M: 10 and B: 2. To me, this allows for the most transparent sound while giving the best tube breakup. Gain was typically set to just under saturation. V1 has a reissue Tung Sol and V2 is a generic russian tube. I only played through the Fender side of the pre (as it also has a Marshall side) because I much prefer the depth and roundness of the Fender voicing that Frenzel has baked into this pre.  Everything was recorded with an SM 58 at the other end of the room, into a small mixer (set flat) and into the computer's sound card. 

Basses used were as follows: 

Parts P bass (black bass): Bill Lawrence P46, DR flatwounds. 

Parts J Bass (red bass): Bill Lawrence J45, Fender 7150M nickel strings. 

Lakland LOG bass (5 string): Aguilar AG 5P-60, Thomastik Infeld nickel flatwounds. 

Dalibor J. (Croatia) 

DALIBOR SOUND CLIP 1 (jazzy-pop sound)  -  My handcarved archtop jazz guitar 17"(like Gibson L-5) with built in Benedetto PAF humbucker pickup (first issue abt.1990)    Signal goes to Lehle passive splitter and directly to FRENZEL FM-DP1 F+M inputs.  F and M gains are adjusted to edge of saturation/distortion. Strum a chord quite heavy and when you hear slight distortion go back one point.   In this case it's about 3 to 4 (if we imagine points 1 to 10),  Bass =3 Middle=6 Treble=4 Master=5,    Line Out of FRENZEL FM-DP1 goes direct to Computer Audio Card Line In (No other amps,speakers.mics - direct recording) . So we finish with Hardware.  Software used as follows:   Signal goes to Cubase 5 and with Trim Control (very useful) on FRENZEL FM-DP1 strength of signal adjusted so the fader on the mixer is at 0dB   and meter is almost full.  On the pre fader inserts I add just a tuch of Guitar Rig Tube Compressor. That's all and signal recorded dry. On post production added Acusticas Lexicon L480 Hall and Waves slight long delay with one repeat and during  mastering just unnoticable tuch with API equilizer.  Don't be confused with all this software,sound from my guitar and FRENZEL on the input of Cubase is very healty and same timber as on final mix.  hose softwares are just tuch of spices.

Jazzy Pop - Frenzel FM-DP1 - Dalibor Jurasin
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DALIBOR SOUND CLIP 2 (mainstream jazz sound) - My other handmade archtop jazz guitar similar as above with floating pickup.Pickup is vintage Gibson singlecoil P-90? from Les Paul Custom 57' . I done some modification so pickup is not build in guitar,he is floating on my ebony pickguard.  Signal goes to FRENZEL FM-DP1 / M input.  M gain adjusted as above to about 4 Bass=4 Middle=6 Treble=3 Master=5. Line Out of FRENZEL FM-DP1 goes to Evans Custom Amp AR-100 combo with 8"speaker. On Evans Bass/Treble/Reverb=0 just Body=7 and Volume 3-4.   Condenser mike with 1" membrane about 2 ft from speaker goes to Computer Audio Card Mic Input with fantom power and build in mic preamp.  That's about hardware.Regarding software in this case used only SIR reverb Medium Room ambience.

Mainstream Jazz - Frenzel FM-DP1 - Dalibor Jurasin
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BASS GUITAR SOUND CLIPS -  This is a collection of basses and styles played through the Frenzel FM-DP1 preamp. As this preamp has been typically aimed at guitar players, I was interested to try it as a Bassman-type preamp for my bass rig. it is a hand wired, point to point pre with two tubes. I have always gravitated toward the Bassman preamp and I have been very happy with the results (and the price point) of the Frenzel unit. 

Bass 3 - Frenzel FM-DP1 - Dalibor Jurasin
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Bass 4 - Frenzel FM-DP1 - Dalibor Jurasin
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Bass 5 - Frenzel FM-DP1 - Unknown Artist
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Bass 6 - Frenzel FM-DP1 - Dalibor Jurasin
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Bass Guitar Video  by Featured Artist Dalibor Jurasin

Basses used were as follows: 

Parts P bass (black bass): Bill Lawrence P46, DR flatwounds. 

Parts J Bass (red bass): Bill Lawrence J45, Fender 7150M nickel strings. 

Lakland LOG bass (5 string): Aguilar AG 5P-60, Thomastik Infeld nickel flatwounds. 

Dalibor J. (Croatia) 

Vintage "Guitar Magazine" Review by Sean O'Bryan Smith  
“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:  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

Customer Reviews 


FM-DP1-RM - The "FM-DP1R  by FRENZEL is as described on website. With good sale offer was made on time with fast shipping. First impression was light weight and that it had retro vintage sound with endless combination from two inputs, etc. FM-DP1R used as tool/part in soundchain can give strong hardrock/blues/jazz rhytmic warm sound when used direct in mixer or return loop of tube amp. Used to maximum as preamp effect in guitar tube amp input with classic or ultra gain...sound became extreme powerfull, best for leadparts...and no hum at all - by Klaudio T. (Oslo,Norway)   


FM-DP1 - Hi Jim, Long time FM DP1 user here - it's still doing a great job 11 years later! Many thanks, Tom R. (New Zealand) 


FM-DP1  - 5.0 out of 5 stars. Fender and Plexi Tone Lives in the Frenzel FM-DP1 Tube Preamp. Packaged very well! Great tone! I run an ABY switch into both channels of this tube preamp and output into a ABY switch with one output lead going into a Mesa CabClone and the other output lead into a Hughes & Kettner RedBox, then over low-Z to my mixer and out over USB into my DAW running Reaper. The mix obtainable through the tone stack and gain stages of this preamp provide a wide range of tone, from bottom end rich cleans, to clipping break up for widely adjustable dirt! The two different cabinet emulators really leverage the preamp tone and deliver two distinctly different personalities to the mixer. A great and small studio rig! Salvatore G. (Washington)  


FM-DP1 800 PREAMP - I am blown away!  This thing exceeds all my expectations.  It is fantastic for recording, but as a bonus it makes my 25 year old Crate go from sounding like a 25 year old Crate to sounding like a million bucks.  Hopefully some of my friends listen to my praises and order one for themselves.  Thanks again for the awesome product and keep up the great work!! Have a great day! Chris B. (North Carolina)  

FM-DP1  - Jim & Crew, -  All I can say is WOW!! This preamp sounds awesome with my Pedulla 5 string bass. I'm using a Y cable combining F&M gain  and the tone is incredible! I have played most of the high end pre's out there (I'm an old guy too)and this pre smokes all of them, not to mention the build quality, absolutely top shelf. I never really thought I would find that sound I had in my mind,,now I have. Thanks to all of you and your outstanding artistry and craftsmanship! Almost forgot,,This thing is dead quiet,,UNBELIEVABLE!!!  Thanks again,  Jeff R. (Ohio)  


FM-DP1 Hey Jim, A massive thankyou fore the preamp.. it arrived on Tuesday.. customs is busy this time of year. Well, what can I say other than I love it! The quality of your builds is unsurpassed! Thank you too for the extra level controls, I’ve used them all already in lots of exciting combinations... the versatility of this preamp, especially with power amp upgrade is sheer brilliance, a piece of kit never to be parted with! And the tones, oh the sweet sweet tones and super quiet operation make this preamp a sheer joy...and plenty of night time rocking out on the headphones when the kids are in bed! Thank you Jim and the team at Frenzel!   Andy J. (Great Britain)

FM-DP1/6SL7 - Thanks Jim and crew. What a cool piece! Love it! Love the DP1! Exactly what I was hoping for. I have a collection of various vintage Peavey steel amps and guitar amps for different gigs. Church, barroom, big, small, need to have multiple rigs set up sometimes. The DP1 lets me get my favorite preamp tube tone with any of my 5 PVs. Just fantastic! Octal preamp 6sl7 goodness on any amp I need. I love tube on front end/solid state on back end. Steel guitar needs clean power or it gets nasty, the DP1 gives me that wonderful bouncing off the strings feeling that tubes give, and the PV does the rest and fills the room cleanly. Love how I can grease it up a bit by tweaking gain and master.  I use your Retro Deluxe to record with and for certain gigs. DP1 is gonna be my main live secret weapon now! Gonna keep Retro 5a3 for studio work. DP 1 is so easy to pack in my bag. What a great product and service you do. Super value. Love my sound! Tommy C.(Florida)  


FM-DP1/6SL7 Hi Jim & Co.- Wanted to let you know that I received my FM-DP1 preamp yesterday evening and I am extremely pleased with it! This is my second preamp from you, the first was an older white-faced model that I purchased a few years ago used. It has 12AX7’s in it (the new one that you made me uses 6SL7’S).  I use your preamps for playing bass through and I love them! They are wonderful for this! (although, not for everyone I’m sure!) I am a certified “gear whore” and have a lot of experience in my 60 years with all kinds of gear. I believe that your preamps (and maybe some all tube amps) have great potential to be marketed toward bass  Rick H. (Washington)


FM-DP1 PREAMP CUSTOMER REVIEW - I recently purchased a FMDP-1 preamp to use on my Jerry Garcia speaker rig, I’m constantly chasing his guitar tone and I can honestly say I got much closer with this preamp rigged to the setup, thanks a ton for the warm clean tones and the classy vintage look. Forever Grateful.  Daniel Douville (California)  


FM-DP1 Preamp - This thing sounds amazing with my IR cab sims - exactly what I was hoping it would be... 
Kindest Regards, DW (Texas)

FM-DP1  - Hi Jim, How are things? I hope everything is just great! Just wanted to let you know that I received the preamp some time ago and it arrived safe and whole. Really dig it!! Extremely versatile in terms of sound possibilities. The 2 watt power amp section is a wonderful feature! Perfect for playing at home without driving the neighbors nuts. It sounds amazing too, I am actually currently using the preamp 2 watt amp as my main amp (through a cabinet with a 12" Jensen alnico speaker) for some recordings I am doing at home and it works just great! Anders H. (Switzerland) 

FM-DP1 - Hi Jim,  I 've received the preamp and am very pleased. I'm sure I'll discover more as I experiment, but It does what I hoped it would in softening and refining the attack with a solid state amp. Still clear and articulate but without the clinical starkness that often comes with solid state. The care with which you build your products comes across in everything including the shipping. Thanks, John H. (Toronto, Canada)

FM-DP1/800 - Hello there... I know its been a long time since we had spoke via email. Just to let you guys know I love this FM-DP1 preamp. I'm have so much fun with this preamp...great product. When I expand system I will be using your product and also I do tell others about Frenzel amp. Erik C. (California) 

FM-DP1 "Deluxe Plexi 1" Preamp -  Finally got a chance to put it through some paces this weekend. Used on a P-style bass for a recording session. Sweet! Many thanks for the excellent product. Al S. (New Mexico)

FM-DP1 - Gentlemen,  Much satisfied with your product! Gives my tone a whole new life. I like my tone to start clean and crisp, and build from there. The “M” channel has that crispness I like, and switching to the”F” channel gets me those rich overtones I love so much! Attached are some pics of the oak cabinet I made for it. Thanks very much!   Brian S. (California) 

FM-DP1 Hi Jim,  I just wanted to let you know I love my dual pro preamp. Just what I was looking for.  I am using it with a Torpedo CAB cabinet/power amp/mic simulator and it's extremely hard to tell that combination from a cranked up old favorite but totally controllable. Great live  or in the studio. Thanks again.  Junior Wilson  (

FM-DP1 - Hi Jim, I have received the FM-DP1 and am enjoying getting to know it. It’s remarkable how many options of warmth I have available to me now. I am using an Acoustic Image Clarus Series 4 (not sure if you are familiar with it) but the ¼”instrument in seems to be a very low impedance? Meanwhile, by happy accident - the xld channel is perfect, gives the sound(s) I love. I seem to use far less power and not have feedback issues etc. I now feel some relief that I had the happy accident of requesting an xlr out. I am very grateful to you for the quality work you have done here Jim.. Thank you for the quality preamp, David O. (New Jersey)

FM-DP1 - Frenzel Team - The FM-DP1 pre-amp arrived to day in great shape. WOW, I am blown away, I played it through a Roland 40 GX and a Fender Mustang III V2, pure tube sound!! Very well built, Thanks so much!!!    Joe VK  (Ohio)    


Hello, Last month I got my Frenzel DP-1 preamp in the mail, and have been playing it exclusively through the F channel. It sounds absolutely phenomenal, and has been everything that I hoped it would be. Joseph B. (Colorado)      

FM-DP1 - "Warm Smooth Bass Tone Found - Melted Chocolate Flowing Over A Warm Brownie" - Dear Frenzel, I purchased an FM-DP1 about 3 years ago, and have used it to sculpt my guitar tone with great success. However, one weakness that I always seemed to run into when I was recording tracks, was getting the bass to have that warm, round, and smooth “thickness” that seems so elusive. I tried all sorts of options without real true success. I would have to run the bass through amp simulators to even get close, but it was never quite right. I could not find that tone. I even bought another bass to see if that would help, and it didn’t. So I began to explore tube-based Direct-In boxes, but found them to be too expensive. I then began to explore a DIY option to build my own tube-based DI box, but that wasn’t easy either. This morning I was going about my business, and had the Tube DI on my mind, and suddenly I had an idea. “Wait a minute, my FM-DP1 is all tube, and it is a preamp, surely, I could run that Direct-In to my Focusrite interface.” So I did just that. I set up a ProTools session where I ran tests on the Focusrite’s DI, the FM-DP1 Fender voicings, and the FM-DP1 Marshall voicing. I did the tests with both of my bass guitars: A 2004 Ibanez Iceman with humbuckers, and a 2015 Fender Squire J-Bass. In about 3 seconds I heard the tone I had been longing for. There it was in its glory! I achieved that thick, warm, smooth and beautiful tone immediately when employing the Ibanez through the FM-DP1’s Fender voicing. Gain was minimal, but if I wanted dirt, it was easy. The Fender J-Bass gave incredible deep throbbing, but rich and smooth tones with more detail (like pick attack, etc.), but both sounded spot-on. It was like melted chocolate flowing over a warm brownie. The FM-DP1 isn’t really marketed this way (as a Direct-In), but believe me…it sounds majestic, AND it just saved me about $745 on a tube Direct-In box. Thanks Frenzel!!! (Ignacio Hernandez, Planets of Grace - Florida)


FM-DP1 - Hi Jim got the preamp after the UPS man left it at the neighbors house, but my wife tracked it down. You  sure  know  your stuff.  It works great!  Adds headroom, great volume control, awesome tone. Just what you said. Dwight H. (Colorado)  

FM-DP1 - Hey Jim,  The brown truck dropped off the FM-DP1 this afternoon.  You guys sure know how to package; I think that box could've fallen off a ten-story building and the amp would've survived. Anyway, I connected it to my ART SLA2 power amp, and from there to one of my Avatar bass cabs.  Started listening for noise.  Well, there wasn't any, even with the gains up to the point where I would've instantly gone deaf if I'd even touched a string on my Precision. Looking for my tone, I started with how I normally set passive tone stacks for a slight mid cut and a slight bass boost, but after a few minutes I found myself getting nowhere.  Then I remembered, from the manual, "You will need to experiment."  So, I threw away all the mental notes I'd kept from my old Showman and Bassman days, and just started cranking things.  After a minute or so, I said to myself, "What if I try the deep switch, max out the bass, min the mid, and then max the treble to cut back some of the mid glare because that last piece has always worked with every passive stack I've used." KA-CHING!  Got it!  The sound was deep and full, but at the same time it wasn't rumbly down in the bass like one of my modern transistor rackmount preamps that also has a passive Fender-style tone stack.  And that wasn't the end of it: I started playing pretty loud along with a few MP3 songs I'm learning for my local Praise & Worship band.  All I can say is I've never heard my Precision sound so full in a mix, but at the same time so harmonically rich without being overbearing in that regard.  With almost all my other amps and preamps, I typically have to settle either for a heavy but relatively characterless sound, or for a sound that's loaded with irritating, harmonically-unpleasant content but that has no usable bottom.  By "usable," I mean in that crucial 50-100 Hz range. The trim in back came in handy for a particularly sensitive power amp I own.  This little preamp has tons of gain! Very, very impressed.  And at this price point, it's just crazy good.  Thank you so much for a great design and a great build!  Craig P. (New Hampshire)

FM-DP1 - Hey Jim, I got the FM-DP1 pre-amp you made and it sounds awesome!  What surprised me the most is it not only sounds great for guitar (lots of possible tones), but I was able to easily tweak great harp tones out of it as well, especially on the Marshall side.  Thank you. Charles C. (California)

FM-DP1 - Hi JIM, I received the Preamp and first test are concluant; definitely pleased!!! Thanks again! Gilles M. (New Zealand) 

FM-DP1 - Hi Jim, Super buying experience; fast build, great communication, and fast shipping. The amp was well packed and included a folder to protect the Manual’s Manual, and the personalized Certificate of Sale. Very nice touch! The FM-DP1 preamp makes my Tweed Princeton (5F2-A) sound HUGE. This preamp allows me to “dial in” the desired sound which was not possible before with just one tone knob. So-o-o much better now! Thank you, Mike D. (Maryland) 

FM-DP1 - Thank you fella's  tone just oozes out of it and running through my bassman is fantastic!! Maurio R. (Texas)

FM-DP1 - Jim,- I wanted to say thanks. I tried my small fleet of guitars through the amp, and just played on for hours more than I'd intended on.  I saved my Les Paul Custom for last - and wow!  The 57' classic buckers just shone through the amp like I've never heard before. The best part was that I was finally able to play with the richest tube tone from your FMDP-1 preamp yet without even coming close to waking the wife and kids upstairs. Ralphie had his Red Ryder BB Gun. I have my Frenzel tube amp. (ha ha).Thanks again, Jim.  You are a gentleman and a scholar, and a pleasure to do business with. Matt P. (West Virginia)

FM-DP1 - Wow! What a fantastic guitar preamp. I am incredibly happy with my purchase and will recommend your products to my musician buddies. Just super! Thanks, Steve L. (Wisconsin)
FM-DP1 - Hi! i write to you because i received my preamp today and i'm in love with my new preamp..   it sound really fantastic with my Crate BH5H      2x12" G12-65,     Thank you very much :Vincent D. (Canada)
FM-DP1  - Jim, What can I say thank you so much, this is the sound I have been searching for....I  am guessing you sent me more than I paid for with the cage and handles....that is truly a gift thanks from the bottom of my heart and may God bless you. I will be using this on Saturday it's in a Theater venue I will get photos/audio and video of your work in action..and send them with a testemony ..I believe that my network of "Jerry Garcia" style guitarist that I know will be facinated to know about your workmanship and I will direct them to your ebay listing and web page......cant wait to buy the back-up this summer, PS. I bought this for the F channel  and I found that the M channel is the perfect 70's Garcia tone now I have to get an AB switch....gear gear gear it's good for the ear. Dave Hebert
FM-DP1  - Wow, thanks for this preamp!  A friend of mine had one of your amps, and I liked it so much I decided to try out your preamp.  Before I got this, all I had was a homemade single-ended 6V6 amp with one tone knob.  The tone was ok, but it was a one trick pony.  Now I've got so many good tones, it'll be tough to decide which one to use.  I am really blown away by the versatility.  It sounds good with all my guitars, single coil or humbucker.  I thought I would like the Fender side the best, because that's the type of amp I'm used to playing, but the Marshall side has really sold me.  Matthew F.

FM-DP1 - Do you remember Boris as Frankinstein's monster when a jolt of lighting wakes up Boris the monster...and old Dr. Frankenstein claims its alive!! Its alive!!!. Well my friend you have created the Boris. I miked a Bellari  MP105 into the Frenzel FM-DP1 thru a Peavey Delta Blues 2x10 Blue Marvels.  I patched the FX loop so it bypasses Peavey amp.  This way it won't hurt the Peavey. The Frenzel FM-DP1 adds new dimension to my harmonica. It opens new avenues of sound. I have been honing my harp sound since 1971 and have for all these years to this day tried to make that harp sound like Miles Davis trumpet so you understand my dilema until today. Thank you Frenzel Amps and Gus!  Richard B. (Colorado)  

FM-DP1 - I am including a photo of my rig (see attachment) with your DP-1 into a EH Holy Grail Reverb, into a McIntosh MC2505, into a pair of JBL D120's.  It is the EXACT sound and responsiveness I have been trying to achieve for years. Thanks again, Jeff
FM-DP1 - Just wanted to drop you a line and let you know that I love using the preamp you built for me. It does both the Fender and Marshall sounds very well.  Can't wait until I can buy more stuff!  - Jay L.
FM-DP1 - I received my amp Friday. It's fabulous. Quiet as a mouse and full of great tones.  Be assured I am pleased with the amp you built for me. We will put it through its paces when the season begins in May. Thanks Donald L. - (New York)
FM-DP1 - Hello Jim, Received the preamp yesterday. Been trying it out today. Wonderful tone and made to last. Sounded great through my super reverb clone and very good through my 30 watt solid state. The preamp was packed extremely well, Thanks again Jim God Bless. Doug F.(New York) 


FMDP1- Hi, I got a FMDP1  preamp from you last year. Love it.  Allen H. (Vancouver BC, Canada)

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