JET CITY AMPLIFICATION Custom 22 User manual

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JE ET T C CI IT TY Y A AM MP PL LI IF FI IC CA AT TI IO ON N
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Cu us st to om m 2 22 2
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OW WN NE ER R’ ’S S M MA AN NU UA AL L

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DANGER: RISK OF ELECTRIC SHOCK,
DO NOT OPEN
ATTENTION: RISQUE DE CHOC
ELECTRIQUE!
NE PAS OUVIRIR!
ACHTUNG: STROMSHLAG GEFÄHRDUNG,
NICHT AUFMACHEN!
CAUTION: To reduce the risk of electric shock, do not
remove cover or open rear panel. No user serviceable parts
inside: refer handling to qualified personnel.
WARNING: To reduce the risk of fire or electric shock, do not
expose this amplifier to rain or moisture.
Before using your amp.
Before operating the Custom 22 please make sure of the following:
First, connect the amp head to a speaker cabinet or other
suitable load. Never run the amp without a load connected
to the output.
Connect the power cable into the back panel and then to a
power outlet.
With the amp in the standby position, switch the power to
ON and wait about 30 seconds for the tubes to warm up.
Change the standby switch to ON.
You’re ready to go.
WARNING: If a speaker or suitable “dummy load” is not connected to
the speaker output, output transformer failure is very possible.

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Important Safety Message.
1. Read and keep these instructions.
2. Heed all warnings and follow all instructions.
3. Do not operate near water.
4. Clean only with a dry cloth.
5. Do not block any ventilation openings. Install in accordance
with the manufacturer’s instructions
6. Do not install near heat sources such as radiators, heat
registers, stoves, or other apparatus that produce heat.
7. Protect the power cable from being walked on or pinched
at the plugs, convenience receptacles, and the point where
they exit the unit.
8. Do not defeat the safety purposes of the polarized or
grounding type plug. A polarized plug has two blades with
one wider than the other. A grounding type plug has two
blades and a third grounding prong. The third prong is
provided for your safety. If the provided plug does not fit
into your outlet, consult an electrician for replacement of
the outdated/obsolete outlet.
9. Unplug the amplifier during lighting storms or when unused
for long periods of time.
10. Refer all servicing to qualified service personnel. Servicing is
required when the amp has been damaged in any way, such
as power cable or plug damage, liquid has been spilled or
objects have fallen inside, the amp has been exposed to
rain or moisture, does not operate normally, or has been
dropped.

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Thank you.
We truly appreciate and value your support through your
purchase. If you have any questions or concerns about your
new amp, feel free to email to [email protected]
This Custom 22 was designed in USA, and meticulously assembled
to assure that it meets the highest quality standards and value.
Our ‘Custom Shop’ is a virtual concept, with the base model
assembled in our usual way, and custom variations of the amp
completed in a variety of secondary locations. This means it is
possible some of the features and components may be different
from other Custom 22 amps. Therefor this manual will just cover
the base features.
Thank you for purchasing a JET CITY AMPLIFICATION product, we
hope you love it.
Douglas White
Founder.

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Controls and Operation.
Input Jack
CRUNCH Preamp Gain: Adjust the amount of gain
(distortion) that the amplifier produces in the CRUNCH
Channel. Set it low for cleaner tones, or dial it up for some
tube grit.
BRIGHT switch: On / Off
CRUNCH Master Volume: Adjust the CRUNCH Channel
output level.
CHANNEL 1 / CHANNEL 2 Selection switch.
OVERDRIVE Preamp Gain: Adjust the amount of gain
(distortion) in the OVERDRIVE Channel.
Mid Boost / Low Fat Tone shaping.
OVERDRIVE Master Volume: Adjust the OVERDRIVE
Channel output volume.
TREBLE: Part of the 3-band EQ for adjusting middle
frequencies.
MIDDLE: Part of the 3-band EQ for adjusting middle
frequencies.
BASS: Part of the 3-band EQ for adjusting low frequencies.
PRESENCE: adds an overall brightness, which can be handy
when trying to cut through in a ‘dead’ room.
STANDBY switch: Used in conjunction with the POWER
switch. Use the STANDBY to “warm up” your the tubes
before switching the POWER on or off.
POWER switch: Turns the power on or off.

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Tube Layout.
Custom 22 has 5 12AX7 Preamp tubes and 2 EL84 Power tubes.
The 12AX7 tubes each have unique functions in the circuit, a
brief overview of which is provided here. Counting from the
first 12AX7 which is nearest to the input Jack:
V1 Gain
V2 Overdrive gain
V3 Tone controls
V4 Effects loop
V5 Phase inverter
When changing the Custom 22’s tubes – either preamp or
power tubes –it is not necessary to adjust the bias. This amp
does have a bias adjustment control on the circuit board which
is used for fine-tuning the bias at the factory, and should not be
adjusted by anyone other than a qualified service technician.
Here are some signs that you need to change your tubes:
Excessive noise like squealing, humming, or hiss
Little or no high end/treble
Muddy low end or loss of clarity; amp sounds “muddy”
Mysterious fluctuations in the amp’s overall volume
Low, or no output volume

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Speaker outputs.
Your amp has one 16 ohm output and two 8 ohm outputs.
Use the 16 ohm output for a 16 ohm load.
Use a single 8 ohm output for an 8 ohm load.
You can also connect two 16 ohm loads to the two 8 ohm
outputs.
The output transformer of the Custom 22 is robust enough to
manage a 4 ohm load, using the 8 ohm outputs, but we do not
recommend lower than 4 ohms.

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Register Your Product Online
Please visit www.jetcityamplification.com within 30 days from
the date of purchase as listed on the buyer’s receipt to register
your product. Doing so will enable you to receive the most
current information about our company and products, directly
from Jet City.
Warranty
Jet City Amplification warrants the mechanical and electronic
components of this product to be free of defects in material
and workmanship for a period of one (1) year from the original
date of purchase, in accordance with the warranty regulations
described below. If this product shows any defects within the
specified warranty period that are not excluded under this
warranty, Jet City Amplification shall, at its discretion, either
replace or repair the product using suitable new or
reconditioned parts. In the case in which other parts are used
which constitutes an improvement, Jet City Amplification may,
at its discretion, charge the customer for these parts.
If the warranty claim proves to be justified, the product will be
returned to the customer freight prepaid.
Warranty claims other than those indicated above are
expressly excluded.

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Return Authorization Number
To obtain warranty service, the buyer (or his authorized dealer)
must call Jet City Amplification or Authorized Jet City
Amplification Distributor (current list and contact information
can be found at (www.jetcityamplification.com) during normal
business hours before returning the product.
All inquiries must be accompanied by a description of the
problem. Jet City Amplification will then issue a Return
Authorization Number (RA Number).
Once the RA Number has been obtained, the product must be
returned in its original shipping carton. The return
Authorization Number must be printed clearly on the shipping
label on the outside of the box, and included with the returned
product. Both the product in its original package and the
Return Authorization Number must be shipped to the address
indicated by Jet City Amplification at the time the call is made.
Shipments without prepaid freight will not be accepted.

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Warranty Regulation / Exclusions
Warranty services will not be furnished if the product is not
returned with the original sales receipt.
Tubes and loudspeaker drivers are considered maintenance
items and are excluded from all warranty claims.
If the product needs to be modified or adapted in order to
comply with technical or safety standards on a national or
local level, in any country which is not the country for
which the product was not originally developed and
manufactured, this modification/adaptation shall not be
considered a defect in materials or workmanship. This
warranty does not cover any such modification/adaptation,
irrespective of whether it was executed properly or not.
Under the terms of this warranty Jet City Amplification shall
not be held responsible for any cost resulting from such a
modification/adaptation.
Free inspections and maintenance/ repair work are
expressly excluded from this warranty, in particular, if
caused by improper handling of the product by the user.
This applies to defects caused by normal wear and tear of
items such as knobs, tolex and similar parts.
Damages caused by the following conditions are not
covered by warranty:
Improper handling, neglect or failure to operate the
unit in compliance with the instructions given in the Jet
City Amplification user manual.
Connection or operation of the unit in any way that
does not comply with the technical or safety regulations
applicable in the country where the product is used.
Damages/defects caused by force majeure or any other
condition that is beyond the control of Jet City
Amplification

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Any repair or opening of the unit by unauthorized
personnel (user included) will void the warranty.
In an inspection of the product by Jet City Amplification
shows that the defect in question is not covered by
warranty, the inspection costs are payable by the
customer.
Products, which do not meet the terms of the warranty,
shall be repaired exclusively at the buyer’s expense. Jet
City Amplification will inform the buyer of any such
circumstance. If the buyer fails to submit a written
repair order within six (6) weeks, Jet City Amplification
shall return the unit to the customer C.O.D with an
invoice that will include charges for the inspection and a
separate additional charge for freight and packing costs.
Such costs will also be billed separately when a
customer has sent in a unit for repair with a written
repair order form.
Warranty Transferability
This warranty is extended exclusively to the original buyer
(customer of the retailer) and is not transferable to anyone
who may subsequently purchase the product. No other person
(retailer, consumer, etc) shall be entitled to give any warranty
promise on the behalf of Jet City Amplification.
Claims for Damages
Failure of Jet City Amplification to provide proper warranty
service shall not entitle the buyer to claim (consequential)
damages. In no event shall the liability of Jet City Amplification
exceed the invoiced value of the product.

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Technical specifications and appearance are subject to change
without notice. The information contained herein is correct at
the time of printing. The names of companies, institutions or
publications pictured or mentioned and their respective logos
are registered trademarks of their respective owners. Their use
neither constitutes a claim of the trademarks by Jet City
Amplificationnor the affiliation of the trademark owners
with Jet City Amplification. Jet City Amplificationaccepts
no liabilities for any loss, which may be suffered by any person
who relies wholly, are part upon any description, photograph
or statement contained herein. Colors and specifications may
vary slightly from product. Products are sold through
Authorized Re-Sellers only. Distributors and dealers are not
agents of Jet City Amplification and have no authority to bind
Jet City Amplification by any expressed or implied undertaking
or representation.