FRENZEL FM-5F6MB Mini Bassman User manual

Frenzel Tube Amplifiers
www.frenzeltubeamps.com
2010 Copyright by Frenzel Tube Amplifiers. All rights reserved. All designs, technical data, pictures, and information are
copyrighted and may not be reproduced without the permission of Frenzel Tube Amplifiers.
Page 1
FRENZEL TUBE AMPS
FRENZEL TUBE AMPSFRENZEL TUBE AMPS
FRENZEL TUBE AMPS
Owners Manual
FM-5F MB “Mini Bassman”

Frenzel Tube Amplifiers
www.frenzeltubeamps.com
2010 Copyright by Frenzel Tube Amplifiers. All rights reserved. All designs, technical data, pictures, and information are
copyrighted and may not be reproduced without the permission of Frenzel Tube Amplifiers.
Page 2
FRENZEL FM – 5F6MB "Mini Bassman"
The FRENZEL FM - 5F6 MB "Mini Bassman" was "INSPIRED" by one of the greatest Bass - Guitar amps ever built...the
Fender 5F6A Bassman. 40 watts of audio dynamite in small lightweight Tolex cab. Loaded with features...including a
JCM800 preamp for the M channel. Smooth warm Fender blues and jazz tones out of the F channel or super soaring
dynamic rock leads on the M channel.
FEATURES:
Input Jacks isolated from chassis for low noise, eddy currents, and hum.
DC on preamp and driver filaments for low noise and hum.
Star ground system to reduce induced current chassis noise
.
F and M inputs with separate Gains drive a common Tone Stack and Master control. F Input voiced for the vintage
smooth Fender 5F6A Bassman deep, rich, warm tones. M Input voiced for the great Marshall JCM800 high gain mid
tones....or you can use an AB-Y switch and create your own distinct tones.
Classic vintage 3-BAND TONE STACK for extended flexibility in shaping your tone. DEEP switch on Bass control.
BRIGHT Switches on Gain Controls MASTER level control so you can crank the GAIN's up and overdrive the preamp
without overdriving the output tubes
Classic Type Bassman/JTM45 Style Presence control active on both channels.

Frenzel Tube Amplifiers
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2010 Copyright by Frenzel Tube Amplifiers. All rights reserved. All designs, technical data, pictures, and information are
copyrighted and may not be reproduced without the permission of Frenzel Tube Amplifiers.
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Unique NNFB "Edge" switch on the PRESENCE control that transforms the power amp section into a No-Negative-
FeedBack style amp for more open, less compressed tones.
Post output transformer LINE OUT with LINE OUT LEVEL control for recording or driving a power amp. Has an auto
switching internal load speaker simulator if speaker is not plugged into Speaker Out jack.
Class AB fixed biased matched pair of 6L6GC's in the output for fantastic headroom....and smooth blues saturation
sounds.
Custom output transformer for extended lows down to 20 hz. ...plus 4 - 8 - 16 ohm speaker outputs.
Laser Etched Faceplate
Chassis Dimensions: 12"W X 2"H X 8"D
Weight: 16 lbs.
Power Output : 40 watts
Dual Speaker Jacks
Speaker Impedance Selector 4 - 8 - 16 ohms
5U4 rectifier for optimum pick attack and sag...or you can use 5AR4, GZ34 or Solid State Plug-In for different amounts of
sag.
Primary Power Transformer Fuse
Extra long (10') three prong grounded power cord.
STANDBY switch to turn off the high voltage during warm-up. Rock solid point-to-point hand wiring using only the best of
parts...low noise tubular polypropylenes caps, metal film resistors, ceramic sockets, switchcraft 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!
Tube compliment: 3 - 12AX7, 2 - 6L6GC, 1 - 5U4
FRONT PANEL:
- F INPUT
- M INPUT
- F GAIN WITH BRIGHT PULL SWITCH
- M GAIN WITH BRIGHT PULL SWITCH
- BASS WITH DEEP PULL SWITCH
- MIDDLE
- TREBLE
- MASTER
- PRESENCE with NNFB PULL SWITCH
- PILOT LIGHT
- POWER - STANDBY SWITCH
REAR PANEL:
- POWER CORD
- POWER PRIMARY FUSE
- LINE OUT LEVEL
- LINE OUT JACK
- SPEAKER OUT JACK
- SPEAKER IMPEDANCE SWITCH 4 - 8 - 16 OHM

Frenzel Tube Amplifiers
www.frenzeltubeamps.com
2010 Copyright by Frenzel Tube Amplifiers. All rights reserved. All designs, technical data, pictures, and information are
copyrighted and may not be reproduced without the permission of Frenzel Tube Amplifiers.
Page 4
Price : $895.00
UPGRADE OPTIONS:
1. 100 - 240 VOLT POWER TRANSFORMER - for operation outside the USA. Please specify line voltage. Add
$75.00
2. EDGE FOOTSWITCH - adds jack to rear panel for footswitch control on the NNFB EDGE switch. Includes
classic heavy duty footswitch with LED. Add $60.00
3. POWER ATTENUATOR - Built-in power attenuator provides three power levels. 10 - 20 - 40 watts. Add $75.00
4. VINTAGE STEEL CAGE - steel perforated cage provides protection for tubes and maximum ventilation for long
tube life. Includes "easy to carry" Fender style strap handle. Add $100.00
5. CUSTOM TOLEX HEAD CABS, COMBO CABS AND SPEAKERS - Please see the CABINETS page on our
website for more details
User’s Operation Guide:
FRONT PANEL CONTROLS:
F INPUT – input for F preamp.
M INPUT – input for M preamp.
F GAIN – sets the volume and the point at which overdrive distortion is produced by the M preamp. Set at ¼ for
initial setting.
PULL BRIGHT SWITCH ON F GAIN - This switch enhances brightness at lower level settings of the F Gain
control. As the control is turned up, there will be less effect . At the max setting of the F control there is no
effect.
M GAIN – sets the volume and the point at which overdrive distortion is produced by the BRIGHT preamp. Set at
¼ for initial setting.
PULL BRIGHT SWITCH ON M GAIN - This switch enhances brightness at lower level settings of the M Gain
control. As the control is turned up, there will be less effect . At the max setting of the M control there is no
effect.
MASTER – sets the maximum output of the preamp and the point at which the output tube saturates. The higher
the setting on the MASTER, the sooner the output tube will saturate and produce output tube overdrive
distortion. Set at ½ for initial setting. Use the GAIN to adjust the preamp overdrive. As the GAIN is increased the
preamp will begin to produce preamp overdrive distortion. Turn the MASTER up for output tube overdrive
distortion. By adjusting the settings on the GAIN and MASTER you can set your desired amount CLEAN and
OVERDRIVE tones.
TONE STACK – is a three band Bass, Middle, and Treble tone filter. The controls are interactive in shaping the
tone. You will need to experiment to find the best setting for your playing requirements. Initial settings for all
three controls is the ½ position
BASS – attenuates the Bass frequencies from 10hz – 100hz as it is turned down.
PULL DEEP SWITCH ON BASS – This switch enhances the Bass and attenuates the Treble.
MIDDLE – is a 500 hz notch filter that dampens the middle frequencies. As you turn the control down it deepens
the notch.
TREBLE – attenuates the high frequency tones from 1000hz - 15000hz. As it is turned down, the MIDDLE control
will have less effect.
PRESENCE – boosts the high frequency range and gives the amp more bright punch. Set at ½ for initial setting.
( Please Note: a scratchy noise is normal when adjusting the PRESENCE control. This is caused by the DC
current running through the control contacts. It only occurs while adjusting the control and will not affect the
operation of the amp. )

Frenzel Tube Amplifiers
www.frenzeltubeamps.com
2010 Copyright by Frenzel Tube Amplifiers. All rights reserved. All designs, technical data, pictures, and information are
copyrighted and may not be reproduced without the permission of Frenzel Tube Amplifiers.
Page 5
EDGE PULL SWITCH – when pulled out will turn off the negative feedback in the amp which produces a boost in
the volume and a more dynamic less compressed tone.
POWER STANDBY ON SWITCH – In the STANDBY position the power is turned on to filaments of tubes. Pilot
lamp will light up when switch is turned STANDBY position. Allow tubes to warm up 3- 5 minutes before turning
to ON position. This protects tubes and lengthens tube life. Turn to STANDBY position when amp is temporarily
not in use.
REAR PANEL CONTROLS:
EFFECTS LOOP – is a passive insertion point between the preamp and the power amplifier. The SEND jack is the
output of the preamp. The RETURN jack is the input to the power amp. For normal operation these two jacks are
connected together by a push/pull switch on the SEND LEVEL. To use the EFFECTS LOOP, pull the switch out
on theSEND LEVEL control. This will open the loop and allows you to insert an effects unit into the jacks. The
SEND LEVEL controls the output level of the SEND jack and can be used to adjust the level to meet the
requirements of the input drive level your effect. Boost and distortion pedals can be used in the loop, but they
usually work better in the front of the amp before the preamp. This is what they were designed for. The loop
works best with studio digital effects that are designed to go after the preamp like Chorus, Delay, Reverb, Mixer,
Volume, etc. ( Only on amps with the Effects Loop upgrade.)
The SEND jack can also be used without the EFFECTS LOOP function to drive a recorder, mixer, or another amp.
This function does not require the switch on the SEND LEVEL control to be pulled out. ( Only on amps with the
Effects Loop upgrade.)
LINE OUT - is a post output transformer LINE OUT jack with LINE OUT LEVEL control for driving another amp,
mixer , recorder etc. It can be used without a speaker plugged into the amp. There is an internal load connected
by a switch on the speaker jack if a speaker is not plugged in. This internal load simulates the speaker and will
give you loaded clean and output distortion tones. Use a shielded cable to connect the LINE OUT to another
device. The LINE OUT also works with headphones.
LINE OUT LEVEL – controls the output level of the LINE OUT.
SPEAKER JACK– connects output of amp to speakers. The jacks are wired in parallel.
IMPEDANCE SELECTOR – selects the output impedance for the speaker to 4 – 8 -16 ohms. Set the switch to
match the impedance of the speaker.
FUSE - protects the power supply. Use a 3 amp SLO-BLO type fuse.
POWER CORD – connects amp to electrical outlet. The power cord is a three prong grounded cord. Always plug
into a grounded outlet to prevent electrical shock. The line voltage is shown over the power cord bushing. Be
sure that the voltage matches your line voltage.
TUBES – The amp comes standard with the tubes shown below, but you canuse other tubes for different tones
and overdrive. For maximum clean and little or no preamp overdrive, you can use a 12AU7 in the V1 position. A
5AR4 will give less compression and a tighter sound in place of the V4 - 5U4 RECTIFIER. You can also substitute
5881's, KT66's, KT88's, 6550's in the output stage V5 and V6 for different saturation and overdrive tones
.
6L6 - V6 OUTPUT
6L6 – V5 OUTPUT
12AX7 12AX7 12AX7 5U4
V1 - PREAMP V2- PREAMP V3 – DRIVER V4 – RECTIFIER
TUBE LAYOUT CHART FM-5F6MB