Diezel VH2 ManualTable of Contents
Chapter One: Safety
1.1 Safety Warnings

Chapter Two: Using your VH2
2.1 Mains Connections, power and Standby
2.1.1 Mains/connect to power outlet
2.1.2 Power up, Warm up, Standby off
2.1.3 Power tube caution
2.1.4 Operating Temperature
2.1.5 Power Tube Information

Chapter Three: Peripheral Connections
3.1 Front Panel Connections
3.1.1 Signal In
3.1.2 Connection Information
3.1.3 Cable Selection
3.2 Rear Panel Connections
3.2.1 Send/Return Loop
3.2.2 Reasons for Dynamic Losses in the Effects Loop
3.2.3 Speaker Connections

Chapter Four: The Two Pre-Amplifiers
4.1 Pre-Amplifier Duties
4.1.1 Channel One
4.1.2 Channel Two
4.2 Pre-Amplifier Tubes
4.2.1 Noise and Microphonics

Chapter Five: Power Amplifier
5.1 Tone and Volume of the Power Amplifier
5.1.1 Master Volume
5.1.2 Presence
5.1.3 Deep
5.2 Power Amplifier Tubes
5.2.1 Function
5.2.2 Selection
5.2.3 Life Span

Chapter Six: Functions and Switches
6.1 Channel Selection

Chapter Seven: Maintenance and Cleaning
7.1 Cleaning
7.2 Care
7.3 Tube ChangeChapter One: Safety and Warranty
1.1 Safety warnings
We would like to stress the importance of the following points, for reasons of yourpersonal safety, product longevity and product liability.
Do not use the Amplifier in or near wet locations
Do not store the Amplifier in damp or wet locations
Do not operate the Amplifier on voltages other than those designated on the rear panel ofthe amplifier.
Do not open the panels of the amplifier. No user serviceable parts inside. Your VH2 operates
on very high internal voltages, which may still be present after the Amplifier has been turned
off and disconnected for a while.
Do not use the Amplifier for anything other than its designed purpose: To Amplify Electric
Guitar Signals
Do not use fuses other than those intended and specified for the Amplifier
Do not use 2-conductor extension cords or anything other than 3-polegrounded outlets forthis appliance. Your life may depend on it!
Please observe the following points when transporting your VH2:
The VH2 is a tube-powered amplifier; therefore it is sensitive to shock especially after playing
the amplifier for a while. Please store and transport your amplifier gently and try to avoid
extreme temperatures, which might produce condensation, resulting in moisture on internalcomponents. Usually a 60 Minute acclimatization period is sufficient to ensure safe operation.
The amplifier should be stored in a controlled environment, and it should be transported in asuitable flight case. Make sure the amplifier gets transported in its normal operating position,
not upside down or on its side. The VH2 design incorporates a very potent power amplifier. It
is configured to deliver satisfying guitar tones at most volume levels. In its normal
operational volume level (75-80dB) it will provide beautiful tones with very little coloration.
For reasons of your own safety, please do not run the amplifier above these levels forextended periods of time without wearing a hearing protection. Hearing Loss is a long-term
ailment, and is not normally curable.

Chapter Two: Using Your VH2
2.1 Mains Connections, Power and Standby
2.1.1 Mains/Connection to Power Outlet
Please make sure that both switches (Power and Standby) are in the off position before
connecting to the mains circuit. Verify line voltage before connecting the power cord. Neverstart the VH2 without connecting speakers to the proper terminals. (See 3.2.3)

2.1.2 Power up, Warm up, Standby off
First, turn the Power switch to on (facing up). The indicator light will turn on. This starts thetube heating process. After about 40 seconds, the tubes should be sufficiently heated fornormal operation. Your VH2 is then ready for operation and the standby switch can be turned
to “run” (also facing up). Premature activation of the standby switch will lead to unnecessary
tube stress and subsequent reduction of the power tube’s life span.

2.1.3 Power Tube Caution
Tubes are electronic components that function only with vacuum intact and under very highoperating temperatures. Each tube has one or more heating filaments, much like a light bulb.
These filaments heat up the anode of the tube. If you switch the standby switch to the “run”
position before these anodes have reached their operating temperature (when the anodesurfaces are not heated evenly), this causes undue stress to the tubes and their related
components inside the amp. Always give the amp its much needed warm-up time, even ifmusical inspiration hits you with a full force.

2.1.4 Operating Temperature
It will take a little more time after warm-up until everything inside the amp is working insync and to its fullest potential. A trained ear will notice a slightly warmer tone and better
complexity in tone after playing the amp for a short while. It’s like stretching before
exercising.

2.1.5 Power Tube Life
The power tubes of your amplifier are subjected to a certain aging process. Once signs ofaging, such as unreliability or unusual noise, are detected, we suggest that you replace all
power tubes at once. Matched tube sets age relatively evenly, so our experience suggests.
This means that if one goes, the others are not far from meeting the same fate. The aging
process manifests itself by a depletion of a thin layer of wolfram on the anodes. This can takeanywhere from 6 month to 5 years, depending on the amount of use of the amplifier.

Chapter Three: Peripheral Connections
3.1

Front Panel Connections

3.1.1 Input Jack
The input jack (“IN”) receives your Electric Guitar signal by means of a shielded guitar cordwith 1/4” mono style plug.
Your guitar cord is an important part of your signal chain and its quality and construction
type clearly affect the overall tone of your rig. Try and buy the best quality guitar cord thatyou can or want to afford. Call us if you have doubts and need recommendations. This iswhere the smart “weak link” comment comes in.

3.1.2 Cable ABC
Some cords and cables sound very neutral; others colour the sound spectrum and/or
attenuate high frequencies due to capacitance inside the wire and the shield. What are wetalking about? OK. A capacitor is used in electronic crossovers, amongst other things, todivide low and high frequencies. Capacitance in a cable cuts your guitar’s high end to acertain degree. Generally, the longer of a cord you use, the more of the cord’s inherent
characteristics will be audible.

3.1.3 Cable Selection
In certain circumstances, it is desirable to match a guitar cord to a specific instrument. One
may use the otherwise undesirable qualities of a cord to one’s advantage, if one has the timeand patience to experiment with different cords and guitars. This should be done while
playing with your band, or while recording. Sometimes it is difficult to tell a component’s trueadvantages until it is used in the right context. A guitar that has very piercing highs could
theoretically be tamed down somewhat by using a long guitar cord that offers some high-end
attenuation. The loop of your VH2 send signals at higher levels and impedances, whichmakes this section of wiring less sensitive. You should still use reliable and good quality
wiring for all loops.

3.2 Rear Panel Connections

3.2.1 Send/Return Loop
The system consists of a series loop. The individual channel volume controls determine
the signal strength at the send jacks. The range is ... to +10dB. The output impedanceis 4.7 kΩ. To use the Send/Return Loop, connect the “Send” to the “return” or “input”
or “in” of the effects unit. Be sure to adjust the input level of the effects unit to theamplifiers level. Most effects units have led bar or other level control devices. TheOutput of the effects unit must be connected to the return jack.

3.2.2 Top 5 Reasons for dynamic losses in the effects loop
Many different factors can be responsible for loss of dynamics, aside from those mentioned(ADA conversion). A vital point that often leads to frustrations a maladjusted output level ofan effects unit. If the output level is too high, the unit will cause unwanted distortion in thepower amp. If it is too low, then the rig will not sound punchy and might get lost in the bandsound. When used in the serial loop, the output of the effects unit determines the ultimate
drive signal strength of the power amp. The output level should be matched to give the best
possible sound with all channels without over driving the power amp section.

3.2.3 Speaker Connections
The VH2 has 5 speaker jacks. 1 for a 16Ohm load, 2 for 2 16Ohm loads or 1 8Ohm load,and 2 for 2 8 Ohm loads or 1 4 Ohm load.
Some examples: The speaker out jacks are wired in parallel, so a single 16 Ohm cabgoes into the 16 Ohm out. Two 16 Ohm cabs go into the two 8 Ohm speaker outs (inparallel 2 16 Ohm cabs result 8 Ohm overall impedance). Two 4 Ohm cabinets go into
the 2 8 Ohm outs (you’ve guessed it, two 8 Ohm cabs result 4 Ohm overall impedance).

Chapter Four: Two Pre-Amplifiers
4.1 Pre-Amplifiers and their Jobs
The Diezel VH2 comes equipped with 2 different and totally independent preamps. This
allows the artist to play through nearly all musical-styles without having to make majorchanges to his/her amplifier. The preamps are voiced to deliver the most wanted guitar tone
flavour: Clean, Crunch, Heavy, Lead. This design concept delivers stellar guitar sounds withexcellent playability, warm dynamics and razor sharp equalization possibilities. The tone
controls work in an unusually wide range, so a little adjustment does quite a lot. As with somany things, less is often more. We suggest you start exploring the channels with allcontrols set to 12:00 o’clock, and the master volume just slightly cracked open. (To avoid
hearing damage)

4.1.1 Channel One (clean to medium gain)
Clean Tone is a very sensitive subject, because there are so many different ideas on how aclean amp should sound like. Clean tonal textures require much higher dynamic range thandistorted sounds. From hard and percussive sounds to soft, warm, and blossoming tone.
VH2 was designed to offer as many of the clean varieties as possible. Your choice of guitars
and pickups will have a large part in this equation.

4.1.2 Channel Two (low to high gain)
This channel is voiced for single notes, or for very heavy and massive rhythm guitar. Dueto its slight midrange accent and very high gain, it possesses a good punch, will play withease, and gain authority to rule any stage, or studio. The “less is often more” rule applies
here also.

4.2 Pre-amplifier Tubes
The pre-amps are equipped with 12AX7 tubes in all positions. The pre-amp tubes are notdesigned to produce high power output. Therefore, their life expectancy is much higher thanthat of the power amplifier tubes. This is not to undermine their utter importance in overallsound and response of the amplifier. Also, annoying defects like crackling noises and low
dynamics are directly related to defective pre-amp tubes. Like all other tubes, 12AX7 tubes
come in many different gain stages, and offer a wide variety of tonal behaviour. Our choicefor production was made to ensure a wide variety of tones, with low noise and good
reliability.

4.2.1 Microphonics and Bad Noises
The overall performance of pre-amp tubes is easily influenced by external mechanicalfactors. Malfunction in these external components will manifest themselves by a sudden,
high-pitched feedback sound. The input stage is especially suspect to these phenomena. If
one encounters microphonic tube behaviour, then the first tube should be checked as arule. Pre-Amplifier tubes can also cause a hum or other bad noises, like crackling or ticking.

Chapter Five: Power Amplifier
5.1 Tone and Volume of the Power Amplifier
5.1.1 Master 1/2
As the name suggests, this controls the overall, volume of the amplifier. There is also asecond, selectable master volume control, which allows volume adjustments via remotecontrol device while playing.

5.1.2 Presence
The presence knob controls frequencies over 3kHz. Treble is produced and dispersed in avery small beam from the speaker, so be sure to position yourself in the projection area ofthe speaker when making adjustments.

5.1.3 Deep
The Deep Control is an active bass control contrary to conventional bass controls. It controls
the frequencies around 90 Hz without influencing the overall dynamic range of the power
amplifier. Diezel Co. is not responsible for disintegrating speaker cabinets.

5.2 Power Amplifier Tubes
5.2.1 Function
As the name suggests, the power amp section is the part of the amplifier that produces
output power, measured in watts. Preamp signals are sent to the power amp, whichamplifies this signal to a level that is acceptable for loudspeakers. Guitar amplifiers utilize
several different types of power amps, which differ in output power and tone. We chose thetube type power amplifier for its tried and true performance and familiar tonal behaviour.

5.2.2 Selection
Diezel Co. installs the most reliable and best sounding tubes that are currently available insufficient quantities. So it is possible that tube brand and tube type will change during
production. The VH2 utilizes 4 power tubes.

5.2.3 Life Span
Power tubes last 1 to 5 years, depending on care, volume and frequency of use of theamplifier. If you use your amp only once a month, then the tubes will last much longer.
Really. We have heard tubes that are over 10 years old, but it was not a good thing. Tubes
age very slowly; slow enough for the artist to get used to the changing tone. To keep things
fresh, and to keep your tube dealer in business, we recommend re-tubing, cleaning andbiasing once a year if the amp is used frequently.

Chapter Six: Layout of Controls
6.1 Channel Selection
The 2 channels of the VH2 can be selected manually by activating the select switch for either
channel. Alternatively, a foot switch can be connected to remotely control the channel
selection.
• Channel One
Control perimeters include Gain1 , Volume1, Treble1, Mid1, and Bass1.
• Channel Two
Control perimeters include Gain2, Volume2, Treble2, Mid2, and Bass2. This channel can beselected via the toggle switch, or via the Diezel 2-button foot switch FS 2 on the back.

Chapter Seven: Maintenance and Cleaning
7.1 Cleaning
Never use anything wet to clean the amplifier, any amplifier. Usually, it is sufficient to wipe
down the outside of the amp with a slightly moist cleaning rag. Do not use abrasive cleaningchemicals. Sometimes a vacuum cleaner can be used to remove dust and dirt from nooks
and crevices. Do not remove the chassis from the housing to clean the amp; the inside ofyour amp carries dangerous Voltages.

7.2 CareBe gentle with this Amplifier. Any mechanical shocks, extreme temperature changes, damp
environments, and other extreme conditions (dust, wind) can substantially shorten tube life.
In some cases, even the amplifier life. Do not block the air circulation grilles in the front andin the back of the amp. Do not push the amp right up against objects that would interferewith its normal airflow. The top of the amplifier might get warm after a prolonged use; thisis normal, but will melt your ice cream and definitely ruin your beer. Never put beverages
on top of the amp where they could spill and flow inside the amplifier.

7.3 Tube Change
Tube changes are only to be performed by authorized service personnel. If power tubes withdifferent values than the stock tubes are to be installed, then the amplifier must be re-biased
before operation can be resumed. The amplifier uses a two circuit bias system. It is quick
and easy to accomplish biasing but were commend that you refer to trained professionals toattempt this procedure.

The Diezel Company wishes to express their gratitude andcongratulate you on your decision to purchase the Diezel Lil Fokker
Amplifier.