JET CITY AMPLIFICATION JCA20HV User manual

JET CITY AMPLIFICATION
JCA20HV
OWNER’S MANUAL
Thank you for your support!
Your JCA20HV was designed by the world-renowned tube amp
designer Mike Soldano, in SEATTLE, WASHINGTON, and meticulously
assembled to assure that it meets the highest quality standards and
value.

DANGER: RISK OF ELECTRIC SHOCK, DO NOT OPEN

ATTENTION: RISQUE DE CHOC ELECTRIQUE!

NE PAS OUVIRIR!

2

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.
This symbol, wherever it appears, alerts you to the presence of uninsulated
dangerous voltage inside the enclosure – voltage that may be sufficient to
constitute a risk of shock.
This symbol, wherever it appears, alerts you to the important
operating and maintenance instructions in the following
document.
IMPORTANT SAFETY INSTRUCTIONS:
1.
Read and keep these instructions.
2.
Heed all warnings and follow all instructions.
3.
Do not operate near water.

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4.
Clean only with a dry cloth.
5.
Do not block any ventilation openings.
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, 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outdated/obsolete outlet.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 lightning storms or when unused
for long periods of time.
10.
Refer all servicing to qualified service personnel. Servicing is
required when the product has been damaged in any way,
such as power cable or plug damage, liquid has been spilled or
objects have fallen into the product, the product has been
exposed to rain or moisture, does not operate normally, or has
been dropped.
Before operating your JCA20HV please make sure of the following:

First, plug the JCA20HV head into a speaker cabinet.

Plug the power cable into the back panel and plug the cable into a
power receptacle. Turn on the power switch on the amplifier and
wait about 30 seconds for the tubes to warm up.

Turn on the standby switch.

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
Turn up your volume switch on your guitar and impress your
friends with your amazing new tone.
WARNING: If a speaker or suitable “dummy load” is not plugged into the
speaker jack, output transformer failure may occur.
The JCA20HV is a 20 watt, single-channel guitar amp head, voiced by
SOLDANO for great vintage rock tones.
The tone controls are interactive; each control will affect the others.
This gives you the flexibility to dial in all the unique and subtle tones
you've been searching for.
JCA20HV also has a presence control that lets you add high-end
sparkle, and a depth switch which boosts the low end. Other features
include a post-EQ solid state effects loop and multiple speaker
impedance outputs.
Controls:
Input Jack: Guitar cable goes here (the other end should probably be in the
guitar)

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GAIN: Adjust the amount of gain (distortion) that the amplifier produces.
Keep it low for clean tones, or dial it up for some tube grit.
BASS: Part of the 3-band EQ for adjusting low frequencies
MID: Part of the 3-band EQ for adjusting middle frequencies
HIGH: Part of the 3-band EQ for adjusting middle frequencies
MASTER: will let you adjust how loud the output will be.
PRESENCE: adds an overall brightness, which can be handy when trying to
cut through in a ‘dead’ room.
DEPTH: enhances the amplifier’s low-end frequencies to give extra
heaviness to your sound.
STANDBY switch: Used in conjunction with the main POWER switch. Use
the STANDBY to “warm up” your amp’s tubes before turning on the POWER
switch. Always put the amp in STANDBY before turning the main power
switch on or off.
POWER switch: This is the main power switch for the entire amp. Be sure
that your amp is switched off AND unplugged before moving it.

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TUBE AMP BASICS
Solid state amplifiers are really not much different from your standard
household electronics; you just plug them in and go. Tube amps, however,
are significantly different.
Tube amps carry significant voltage, even when turned off. DO NOT remove
the chassis from the cabinet unless you are a trained tech. The dangerous
voltages are a risk if you start messing with wires and transformers but is
perfectly safe to change your own tubes.
There is no set timeline for changing tubes. If you play every day, a good
rule of thumb is to replace your power tubes once a year and your preamp
tubes every other year. However, it is entirely possible for tubes,
particularly preamp tubes, to last decades.
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

There’s no sound from the amp!
“Biasing” is a technical term that has to do with things like “voltage applied
to the grid” and “moving the operating point into a more linear range.” If
you didn’t understand that, then don’t attempt this yourself.
JCA20HV is a Fixed-bias amp which allows you to “plug and play” EL84
power tubes without needing a bias adjustment.
SPEAKERS AND IMPEDANCE

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Every speaker cabinet has an impedance rating listed in ohms. Think of the
impedance as the speaker cabinet’s resistance to an amp’s power. The
higher the cabinet’s impedance, the more the amp has to work to push
power through it. The goal in any amp/cabinet configuration is the match
the amp’s speaker output impedance with a speaker’s impedance
(sometimes called “load”).
JCA20HV has outputs on the back marked “16 ohm” and “8 ohm.” Use the
correct output for your speaker configuration. If your speaker cabinet is
listed as “16 ohms” use the “16 ohm” output from the JCA20HV.
Speaker cabinets often have a set of ¼” jacks labeled “series” or “parallel.”
This allows you to run a speaker from your head to one cabinet and then
from that cabinet to another one. When you use the “series” output, the
load increases so you add each cabinet’s impedance to determine the
overall load (two 8-ohm cabs in series = 16-ohm load).
When you use the “parallel” output, the load decreases. If all cabinets have
the same impedance, then divide that impedance by the number of
cabinets (two 8-ohm cabs in parallel = 4-ohm load). If the cabinets are of
different impedance, then multiply the impedances together and divide this
by the sum of the cabinet impedances (one 8-ohm cab and one 16-ohm cab
in parallel = 5.33-ohm load). In case of an awkward number, default to the
impedance closes to, but lower than, the number (for a 5.33-ohm load, use
the 4-ohm output).

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WARRANTY
1 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.
2 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 as
described in section 4, 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.
3 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

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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.
4 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.
5 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.
6 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.
7 Other Warranty Rights And National Law
The warranty does not exclude or limit the buyer’s statutory rights provided
by national law, in particular, any such rights against the seller that arise
from a legally effective purchase contract.
The warranty regulations mentioned herein are applicable unless they
constitute an infringement of national warranty law.
Protect Your Hearing

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The US Government's Occupational Safety and Health Administration
(OSHA) has specified the following permissible noise level exposures:
Duration Per Day In Hours Sound Level dBA
8 90
6 92
4 95
3 97
2 100
1.5 102
1.0 105
0.5 110
0.25 115
According to OSHA, any exposure in excess of the above permissible limits
could result in hearing loss. Ear plug protectors in the ear canals or over the
ears must be worn when operating this amplification system in order to
prevent a permanent hearing loss if exposure is in excess of the limits set
forth above. To ensure against potentially dangerous exposure to high
sound pressure levels, it is recommended that all persons exposed to
equipment capable of producing high pressure sound levels such as this
amplification system be protected by hearing protection while this unit is in
operation.

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Specifications
Pre-amp

3 x 12AX7
Power Amp

20 watta

Class A/B, Fixed Bias (Internally Adjustable)

2 x EL84
Power Transformer

Input Voltage – 100v/120v/230v/240v
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.