Two-Rock Custom Reverb User manual

Two-Rock
Custom Reverb
OWNERS MANUAL

Thank you for your purchase of a Two-Rock amplifier
from K&M Analog Designs
As a discerning guitarist, you know the road to
great tone begins with great components.
Our Classic Design, carefully selected parts and
hand-built approach combine to make an extremely
versatile instrument.
Please take the time to read this manual. We
hope it will answer any questions that you may have.
We extend a warm welcome to you as a member
of a select group of musicians who have chosen a
Two-Rock amplifier.

Input Jack- High impedance input to the amplifier. Plug in your instrument here.
Treble Control- Adjusts the high frequency response. In the full counter-clockwise position, high
frequencies are bypassed to ground. In the full clockwise position, high frequencies are allowed to
pass to the next gain stage.
Middle Control- Adjusts the mid-range response. In the full counter-clockwise positon, the tone will
be somewhat “scooped” of mid-range response, emphasizing the highs and lows. In the full clockwise
position, mid-range frequencies are allowed to pass to the next gain stage.
Bass Control- Adjusts the bass response. In the full counter-clockwise position, low frequencies are
cut. In addition, the response of the treble and mid-range controls is greatly reduced. In the full clock-
wise position, low frequencies are allowed to pass to the next gain stage.
Mid Switch- Boosts the mid range frequency response.
Deep Switch- Boosts the low and low-mid frequencies. This is a low frequency contour switch,
changing the low and low-mid response.
Input Gain- Adjusts the overall gain of the amplifier. Start with this control in the 12 o’clock
position. Keep in mind that the amount of gain set here determines the signal level feeding the lead
channel. Low gain settings of this control will require higher lead gain settings for the same amount of
overdrive.
Clean Channel Master Volume- Adjusts the output level of the clean channel.
Bright Switch- Boosts the high frequency response. This is most effective when the input gain is
set at 12 o’clock or lower. The effect is less dramatic as the input gain control is adjusted past the 12
o’clock position.
EQ1/EQ2- This switch allows you to choose between 2 completely different equalization settings.
EQ1 is a lower gain setting, with extended midrange and bass available when used in conjunction with
the middle and bass controls as well as the deep switch. This setting is suitable for any style requiring
a pure clean tone with a nice round bottom and plenty of headroom.
EQ2 is a higher gain setting, allowing a greater signal level to pass to the lead channel. This setting
is suitable for any style requiring a clean to slightly distorted tone in clean mode, and more gain in the
lead mode.
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FRONT PANEL FUNCTIONS

Lead Gain- Adjusts the input level (gain) of the lead channel.
Lead master- Adjusts the output level of the lead channel.
Lead Channel Switch- Sends the instrument signal through the lead circut, adding extra stages of gain
to the signal and enabling the lead gain and lead master controls. To enable foot switch control of this
function, switch must be in the down position.
Bypass Switch- This switch bypasses the tone controls, increasing both level and mid-range response.
To enable footwitch control of this function, switch must be in the down position.
Reverb- The front panel reverb control is the return, or mix, control. The reverb effect is defeated with
this control in th efull counter clockwise position. Use in conjunction with the reverb drive control (see
REAR PANEL FUNCTIONS, next page).
Presence- Adjusts the contour of high-frequency response. The high-frequency response will
increase as you advance the control clockwise.
Stand-by Switch- Should be in the “down” or “stand-by” position when you apply power to the unit.
After a few seconds, place the switch in the “up” position to use the amplifier. You may leave the unit
“powered up” and place this switch in the “stand-by” position to mute the output.
Indicator Lamp- This lamp will illuminate when the power switch is in the “up” position, indicating the
unit is receiving A/C power.
NOTE: All switches are ON in the “up” position
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A/C Input- Connects the amplifier to A/C power via the power cord supplied. Unless otherwise
specified, your amplifier is designed to operate on 120 volts A/C, 60 cycles.
Fuse- 3 AG Type, slow blow fuse. 50 Watt amps use 2.5 Amp slo-blo; 100 Watt amps use 3.5 Amp
slo-blo.
Power Switch- Turns power on.
Ground Switch- Normally left in the center “off” position. If you encounter excessive AC hum or
ground loop noise, try the switch in the other two positions.
Speaker Output Jacks- There are 3 speaker output jacks; 4,8, and 16 ohms. NEVER OPERATE
YOUR AMPLIFIER WITHOUT A PROPER SPEAKER LOAD CONNECTED. Be sure to match the
impedence of your cabinet with the impedence (output) of the amplifier.
Footswitch Jack- The footswitch connects here. The clean/lead and tone bypass functions can only be
activated via the footswitch.
Effects Send- Use this jack to send the amplifiers signal to outboard effects.
Effects Return- Use this jack to connect the output of your effects to the amplifier.
Effects Level- Adjusts the return signal level. It also acts as a master volume control. Do not set fully
counter clockwise, as this will shut off signal to the output section, resulting in no output level. Nor-
mally this control should be set at the 12 o’clock position.
Feedback Switch- This switch defeats the internal feedback circuit located in the preamp section. The
effect is subtle. You will notice a slight increase in high and low frequency response and a decrease in
dimensionality and articulation.
S/N- Your serial number is located here. We strongly suggest that you record this number and have it
handy in case you need service, or in the event that your amp is lost, stolen, or damaged.
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REAR PANEL FUNCTIONS

Each fi ne production tube is tested and matched to our exacting specifi cations. External bias adjustment and
test points are located on the chassis near the output tube sockets. A digital voltmeter and small screwdriver are
required for bias adjustment.
BIAS ADJUSTMENTS:
Power up unit and connect proper speaker load.
Set master volumes and effects return controls to zero.
DO NOT apply any signal to the input during the biasing proecedure!
Take unit off standby and allow a few seconds for the circut to stabilize.
Set voltmeter to Millivolt scale (or lowest volt scale .60 millivolts=.060 volts.)
With meter grounded to chassis and + probe at test point, measure voltage.
A reading of .055 to .060 volts is normal. If not in this range, adjust by turning bias screw SLOWLY a small
amount. Do not set above .070!
For other tube types (5881, 6550, EL34) check with the manufactureer or contact us for recommendations.
Settings higher than .065 with 6L6 tubes may cause premature tube wear and possibly damage the amplifi er.
Keep in mind that tubes vary in quality, and some tubes can handle upwards of 40 ma each (a reading at the test
point of .080!) However, to be on the safe side, use the above as a guide.
WARNING! No user serviceable parts inside! Refer to qualifi ed service person only.
LINE CORD- For your safety, connect to grounded A/C receptacle only.
V1- 12AX7, Rhythm channel
V2- 12AX7, Lead Channel
V3- 5751/12AT7, Reverb Driver
V4- 12AX7, Reverb/effects
V5- 12AX7. Phase Inverter
V6,V7- 6L6GC, Output
V8, V9- 6L6GC, Output (100 Watt)

K&M Analog Designs amplifiers are brought to you by Bill Krinard and Joe Mloganoski.
We know your new Two-Rock amplifier will provide many hours of enjoyment and inspiration in the years
to come. is manual is a resource for some of your questions. Please contact us with any other questions
or comments that you may have. We look forward to hearing from you!
PHONE: [phone]-TONE (8663) (M-F 9am-5pm PST)
FAX: [phone]
ADDRESS: K&M Analog Designs, LLC
619 Martin Avenue, Suite 6
Rohnert Park, CA 94928
E-MAIL: Joe Mloganoski, Product Specialist
[email protected]
Bill Krinard, Chief Engineer
[email protected]
INTERNET: www.two-rock.com
PRECAUTIONS:
DO NOT expose to rain or any other moisture.
DO NOT use cleaning solvents. Wipe exterior with a clean, dry cloth
only.
Refer servicing to a qulified sevice technician.

This is a product of:
K&M Analog Designs, LLC
619 MARTIN AVENUE, SUITE 6
ROHNERT PARK, CA 94928
707-584-8663
www.two-rock.com
SERIAL NUMBER:_____________________________