Frenzel Tube Amplifiers
www.frenzeltubeamps.com
©
2012 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.
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.
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 that a scratchy noise is normal as the Presence control is adjusted. This is caused by the DC
cathode current running through the contacts. It only occurs when the control is adjusted and does not affect the
operation of the amp.)
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.
REVERB – adjusts the Reverb level. (Only on amps with the reverb option.)
POWER SWITCH – turns power ON to filaments of tubes. Pilot lamp will light up when switch is turned to ON
(up) position.
STANDBY SWITCH – turns ON high voltage to tubes. Allow tubes to warm up 3- 5 minutes before turning to ON
(up) position. This protects tubes and lengthens tube life. Turn to OFF position (down) when amp temporarily
not in use.
REAR PANEL CONTROLS:
SPEAKER JACKs – connects output of amp to speakers. 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.
TUBE LAYOUT CHART
=
V3 V2 V1
12AX7 12AX7 12AX7
V4 V5
6L6 6L6
V6 V7
5AR4 5AR4
