Frenzel FM - STP "Super Twin Plexi"

Hi everyone! This is an amp that has a lot of soul...so much so it needs more than specs to describe it. The FRENZEL "Super Twin Plexi" was designed as the ultimate amp for the serious player. We have sold a lot of Retro Twin and Plexi amps .…but this is the first one we have ever built with separate dual "Marshall – Fender" voiced preamps. It comes in three different power levels. The FM-25TPR 25 watt is the standard version. The FM-50TPR 50 watt and FM-100TPR 100 watt versions are upgrade options. There are two independently voiced preamps each with its own separate Gain control, 3 band tone stack, and Master control. One preamp is voiced like the Fender Twin…the other the Marshall SLP Plexi. This amp is a unique one of a kind designed totally for the creative player in mind. It will give you just about any sound you ever dreamed of.

The basis for the design is a combination of two of the greatest vintage amps ever built, the Fender 5F8A Twin and the Marshall SLP Plexi. For those of you who have never looked at the schematics, the amps are nearly identical. The Fender 5F8A twin is basically a 5F6A Bassman with four 5881’s in the output stage instead of two. It also uses the same fantastic cathode follower fed 3 band tone stack. It is a design made in heaven by the tube amp God and passed on to Fender. Marshall copied the 5F6A, added two more inputs, changed to KT66’s in the output and called it the JTM 45…..then followed Fender’s idea about the Twin and went to a four tube output and made the Plexi. Both amps produce such great tones that one is hard pressed to improve on them…so we have designed this amp to be basically both amps in one…plus we have added a few mods to the circuits….and tubes suggested by our “rock on “ guitar buds from all over the world.

We left the output stage design pretty much undisturbed except we replaced the 5881’s Fender used with EL34’s. Marshall did this in his Plexi…it was a great idea which really gave the amp some depth and warmth…...but he did something else that hurt the tone and displeased the tube amp God by going to solid state rectification. This removes all of the natural compression provided by the tube rectifier. Some say, he did this because it provided a faster pick attack….which is true, but the real reason was ...it was cheaper. The bean counters won again! For the purists out there who want the true vintage tube amp sound, you know you can’t get it without a tube rectifier, so we kept the tube rectifier and went a step further by using two 5U4’s in parallel which gives a good compromise on pick attack and compression.

For trannies we chose the Marshall output for the original classic vintage sound. This trannie provides you, the player, with extended low-end warmth and those incredible enhanced Marshall overtones. All the while, maintaining a perfect balance between the highs, mids, and lows. The trannie has 4, 8, and 16 ohm output taps which are selectable by a switch on the back of the amp. For the power supply section we used a monster Hammond for the power, and a large Hammond filter choke. The large power trannie provides great voltage regulation so that you don’t sag when you get on it hard. The voltage is filtered for low hum by an equally large choke.

The heart of any amp is the preamp…it generates nearly all the tones. The preamp in this amp is a killer tone machine like none you have ever heard. It has separate HIGH - LOW input jacks for each channel. This allows you to match your guitar pickup to the input of the amp....and to use an AB switch select either channel for tones you have never heard before! The output of these input jacks feeds two separate preamps each with its own Gain Control, 3 Band Tone Stack, and Master Control. One preamp is based on the Fender Twin preamp circuit, the other is based on the Marshall Plexi preamp circuit. Both Preamps share the same Presence control which is part of the output circuitry. Also, we have put a pull-switch on the Presence control that defeats the negative feedback which allows you to get that “really open” sound. The combination of all these options generates just about any sound you would ever want…from Clapton….to Van Halen…to…. But, if you want to create more sounds we have also installed a Classic 60's style Serial Effects Loop with Return Jack, Send Jack, and Send Level Control. The Return Jack provides Power Amp input. The Send Jack provides preamp output.

The front panel controls are Top Row: Fender - Gain, Bass, Middle, Treble, Master. Bottom Row: Marshall - Gain, Bass, Middle, Treble, Master. Middle Row: Presence with pull switch feedback defeat, Power Switch: (Off, Standby, On). The back panel has two ¼” Speaker Jacks, Impedance Selector Switch 4 - 8 - 16 ohms, Effects Loop: (Receive, Send, Send Return Level Control), Power Line fuse.

We checked the amp on the bench and on speakers. If you like playing clean you will love this amp….but it will also kick and crunch and sing when you crank it up. The sound is clean and crisp and develops three distinct types of crunch and distortion depending on whether you are overdriving the preamp tubes, output tubes, or both. It will give you the great high mids of the Marshall and the warmth of the Twin….and a lot more! The 100 watt upgrade version puts out a "heart throbbing" 100 watts RMS, that sounds like 200 watts RMS through a pair of 12" Alnico Tone Tubbies. It will rattle the walls and the windows.

All the parts in the amp are top-of-the line…..polypropylene caps, metal film resistors, Alpha pots, Switchcraft jacks, ceramic sockets.. etc… The preamp tubes are all brand new JJ's and the EL34’s are a matched EH's This is a rock solid point-to-point hand wired amp…. a real one of kind collectors item.

PRICE: $1095.00