Aeron AP990C User manual

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AP990C
VACUUM TUBE INTEGRATED AMPLIFIER
Manual Rev 1.4.2017
USER MANUAL

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Contents
Preface 3
Illustrations
Safety Notice 5
Installation
Vacuum Tubes 6
In your System 7
Connections
Rear Panel Connections 8
AC Power Connection 9
Operation
Power-up Procedure 10
Direct Power Amp Mode Procedure 11
General Notes about Usage 11
Front Panel Control Function 12
Remote Control Function 12
Maintenance
Test for Quiescent Current of Power Tube 13
Bias Adjustment Setting 13
Servicing 1
Cleaning 1
Disposal and Recycling Guidelines 1
Limited Warranty 15
Specifications 16

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Preface
Thank you for purchasing the AP990C as part of your music entertain-
ment system. The engineers and designers at Aeron have spent count-
less hours of listening and testing to create a Vacuum Tube Integrated
Amplifier of the highest caliber for music reproduction. The AP990C
has been designed to provide you many years of playback.
Before use we encourage you to please read this manual thoroughly to
properly acquaint yourself with its features. We hope you enjoy listen-
ing to Aeron product as much as we have had the pride that we have
taken in manufacturing this fine receiver for your listening pleasure.
If you have any questions regarding the operational functions, contact
your dealer or distributor for assistance.
Thank you for choosing AERON for your audio experience!

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Front Panel
Illustrations
1. Power ON/OFF Switch
2. Input selector: Line in 1-3, Balanced,
Phono
3. VU Meters
. Volume Control
5. 3.5mm Input
6. Direct Power Amp Mode
7. Bias Setting for Power Tubes
8. Plate Current Meter
9. Power Tube Selector
Rear Panel
① ②
③
④
⑤
⑥
⑦
1. mm Phono input
2. Line input (Line 1, Line 2)
3. Balanced input (Left & Right)
. ohms +ve Speaker Output (Right)
5. -ve Speaker Output (Right)
6. 8ohms +ve Speaker Output (Right)
7. AC Mains Voltage Selector
(115V/230V)
8. IEC AC LINE CORD input connection
port
9. ohms +ve Speaker Output (Left)
10. -ve Speaker Output (Left)
11. 8ohms +ve Speaker Output (Left)
12. Direct Power Amp Input
13. Direct Power Amp Mode ON/OFF
Switch
1 . Grounding
①
② ③ ④
⑤
⑥
⑦
⑧
⑨
⑩
○
11
○
12
○
13
⑧
⑨
○
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5
Safety Notices
1. Heed all warnings and follow all instructions in this manual.
2. Do not use this apparatus near water.
3. Clean only with a dry cloth.
. Do not block ventilation openings. Install in accordance with instructions.
5. Do not install near any heat sources such as radiators, heat registers, stoves or another
apparatus that produces heat.
6. Do not defeat the safety purpose of the polarized or grounding type plug. If the provided
plug does not fit into the outlet, consult your Reseller.
7. Protect the power cord from being walked on or pinched, particularly at plugs, conven-
ience receptacles, etc.. Unplug the AC mains cord as well as all other connecting cables
during transportation.
8. Only use attachments and accessories specified by Aeron or your Authorized Aeron
dealer.
9. Use a surge protector on the main AC-Line to this component as well as all other compo-
nents connected to this product. Unplug this apparatus during lightning storms or when
unused for long periods of time.
10. Refer all servicing to qualified service personnel. NO USER SERVICEABLE PARTS INSIDE.
Owner may change tubes.
OTHER SAFETY CONSI ERATIONS
1. ALWAYS disconnect your entire system from the AC mains before connecting or disconnecting
any cables, or when cleaning any component. To completely disconnect this apparatus from the
AC mains, disconnect the power supply cord plug from the AC receptacle.
2. NEVER use flammable or combustible chemicals for cleaning audio components.
3. NEVER wet the inside of this component with any liquid. If a liquid substance does enter your
unit, immediately disconnect it from the AC mains and take it to your Aeron Dealer for inspection.
. NEVER spill or pour liquids directly onto this component.
5. NEVER block air flow through ventilation slots or heat sinks.
6. NEVER bypass any fuse or replace any fuse with a value or type other than those specified.
7. NEVER expose the AP990C to extremely high or low temperatures. If the AP990C has been taken
out of storage from an unheated environment, let the unit acclimate to room temperature before
making any connections and applying power to the unit.
8. ALWAYS keep electrical equipment out of reach of children. This unit has a Protective Cage/
Tube Cover guards against accidently touching the glass tubes that are used for either power
conditioning, amplification, or serving as a VU Meter when the product is in use, thus avoiding a
potential injury and burn. Keep children away. Do not handle the tubes when hot, or wet them.
Only touch the tubes only when they are cold and the unit is unplugged from its source of AC
Power.
9. ALWAYS unplug sensitive electronic equipment such as this unit during lighting storms.

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Installation
Vacuum Tubes
Before operate your AP990C
Your AP990C amplifier is shipped with the vacuum tubes packed in foam
blocks. These must be unpacked and installed before you attempt to operate
the amplifier. Included are two matched pair of KT-88 or KT-150 output tubes,
and two 12AX7, two 6SN7 dual triodes used in the input stage. Proceed
according to the following instructions.
Carefully remove each vacuum tube from its protective foam and match its lo-
cation “V” number (written on the base of the tube) to the “V’ number printed
next to each socket. Firmly seat each tube in its matching socket, taking care to
“key” the tube pins to the socket holes. Retain the foam blocks with other
packing materials for possible future use.
If you are using the optional tube cover, be sure the AP990C is first turned off.
Remove the top cover screws, and install the cover on top of the top plate. Insert
and retighten screws.

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Installation
In your System
To insure normal component life and safe operation this unit must be oper-
ated only in a horizontal (upright) position. Adequate airflow and proper
cooling thereby can occur only if there is no restriction below, behind and
above the unit.
The four special non-marring elastomer feet provide adequate spacing only
from a smooth, hard surface. Never operate the unit while it is sitting on a
surface such as a rug or carpet.
If the unit is to be operated in an enclosed equipment cabinet, an exhaust
fan is desirable so as not to operate the AP990C in overheated ambient air.
The “ambient” operating temperature should never exceed 120oF or 9oC.
Improper installation will cause premature tube failure and will affect your
warranty, as well as the service life of the unit.
It is normal for a vacuum tube power amplifier to run quite warm, and if used
for prolonged periods, hot to the touch. All components within are, howev-
er, operated at safe, conservative levels and will not be improperly affected
thereby, providing the requirements outlined above are adhered to.

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Connections
Rear Panel Connections
All two sets of Single-Ended inputs, one set of Balanced input, one set of mm
Phono input and one set of 3.5mm line level input at front panel are clearly
marked to indicate use.
6-Output binding posts (+) and (-), L & R, for or 8 ohm speaker connection
1 — Power line cord inlet
1 — Power line fuseholder
MATCHING: It is important to use as close as possible an impedance match be-
tween the amplifier and speaker for optimum transfer of power to the speaker
with minimum distortion. In the case of speaker systems with significant varia-
tions in impedance throughout the frequency spectrum, such as most electro-
static types, determine the best impedance match empirically for best overall
sonic results.
It is important sonically that your entire system be connected so that the audio
signal arriving at the speakers has correct, or “absolute” polarity (i.e., non-
inverted). Connect the black or “-” speaker terminal to the wire that connects to
the “0” terminal on the AP990C. Connect the red or “+” speaker terminal to the
wire that connects to the “ ” or “8” terminal on the AP990C, and tighten the
speaker terminals securely to ensure best sonic results.
About Cables:
Use the best available speaker wires and interconnects. Aeron cannot emphasize
this enough. As better components and systems are developed, it becomes in-
creasingly important to avoid the limitations of inferior system interconnections.
Connect the AP990C input the source components only the highest grade of au-
dio interconnect cables. To avoid sonic degradation use the shortest practical
length of cables.

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Connections
AC Power Connection
It is essential that the amplifier be connected to wall AC power receptacle, or a
similar heavy-duty source. If it is connected to convenience receptacles on pre-
amplifiers, etc., the full sonic capabilities of both the AP990C and the preamplifier
will be compromised.
For the very best sonic performance, the AP990C should be connected to its own
AC power circuit branch, protected by a 15 or 20 amp breaker. The other audio
equipment should be connected to a different power circuit and breaker. Avoid
the use of extension cords. If they must be used on a temporary basis, use
1 -gauge or heavier cords.
The AP990C utilizes a compatible grounding system that generally does not re-
quire a “ground lifter” adapter plug on the AC power cord to minimize hum. The
power cord supplied with the AP990C has a standard three-prong grounding plug
to provide maximum safety when it is connected to a grounded wall receptacle. If
there is any question regarding the safety of grounding procedures, be certain to
seek competent help with the installation.
If electronic crossovers or other AC powered equipment are used with the
AP990C it may be necessary to use “ground lifter” adapters on the power plugs of
that equipment to minimize system hum. Generally, the lowest hum is achieved
when the only direct connection between audio common “ground” and true earth
ground occurs in the preamplifier, through its grounded power cord. Other
equipment in the system should have some form of isolation to prevent ground
loops and associated hum.

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Operation
Power-up Procedure
Make sure you have read and complied with the Installation and Connection in-
structions prior to attempting operation.
Power-On
1. Adjust volume control to minimum setting
2. Press the “Power” button to turn unit ON
3. Choose the Audio Source, the source LED indicator is sparkling, wait 30secs
to 1mins, till the LED is ON
. Turn Volume Control to audience level
Shut- own
1. Adjust Volume control to minimum setting
2. Press the “Power” button shut unit OFF

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Operation
irect Power Amp Mode Procedure
AP990C can set as a Power Amplifier.
1. Turn off the AP990C.
2. Connect the signal from preamplifier to AP990C “Direct Power Amp In”.
3. Select the switch to “Direct Power Amp Mode” from rear panel.
. Turn on your preamplifier, turn on your AP990C.
General Notes about Usage
If you turn off the AP990C wait at least five minutes before turning it on again.
This brief cool down period will reduce stress on the output tubes and potential
damage to them.
Aeron does not recommend leaving your AP990C on 2 hours a day as is the
custom of some listeners to achieve maximum sonic performance on demand.
While this is often recommended for solid-state equipment, Aeron does not
recommend this procedure for vacuum tube integrated amplifiers.
CAUTION: Always turn the volume control down when changing program
sources.

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Operation
Front Panel Control Functions
VOLUME CONTROL: Rotate the down or up volume control decreases or
increases the volume level.
INPUT: Allows selection of any of three single-ended input sources 1, 2, 3. Switch
the input selector button through each input as indicated on the panel.
POWER: Toggles power on and off from AC wall outlet to AP990C.
Remote Control Functions
1. Press the button to choose your desire source.
2. Press Volume “up” or “down” bottom to increase or decrease the volume
level.
Remote Control

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Maintenance
Test for Quiescent current of Power Tube
1. Set the volume to minimum.
2. Turn the band switch to “V1”, the current meter will show V1 tube quiescent
current meter should show 20-30mA.
3. After test, switch need set to “OPERATE”, can play music now.
*All quiescent current test of power tube as same.
**If have quiescent current is out of work required, please see the following bias
adjustment setting.
Bias Adjustment Setting
1. If “V1” quiescent current is out of work required, please set the volume to
minimum first.
2. Switch set to “V1”, use a flathead screwdriver adjust to potentiometer “V1
BIS ADJ”, please note the value of the current meter. And different tube cur-
rent will be adjusted as follow:
-KT-88 — 20-2 mA
-KT-100 & KT-120 — 2 -30mA
-KT-150 — 28-3 mA
3. After adjustment, all power tube’s switch need set to “OPERATE”, can play
music now.
*All power tube current adjustment as same.
**For the best results, operate and adjust the AP990C at 220V AC. Adjustment
must be made under zero-signal conditions after least 15-20 minutes of uninter-
rupted stabilization time.

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Servicing
CAUTION: Your AP990C contains sufficient levels of voltage and current to be
lethal. Do not tamper with a component or parts inside the unit. Refer any need-
ed service to your authorized Aeron dealer or other qualified technician. Should
service be necessary, please contact your Aeron dealer, or Aeron Customer
Service Email: [email protected] or [e-mail].
Cleaning
To maintain the visual appearance of your AP990C, occasionally wipe the front
panel and top cover surfaces with a soft damp (not wet) cloth to remove dust. A
mild, non-alkaline soap solution may be used to remove fingerprints or similar
smudges. Cleaners containing abrasives should not be used as they will damage
the brushed grain of the front panel finish.
isposal and Recycling Guidelines
To dispose of this electronic product, do not place in landfill. This product may
contain regulated materials which upon disposal require special reuse and recy-
cling processing. Please contact your dealer or importing distributor for instruc-
tions on proper disposal of this product on your country. Packing and shipping
materials may be disposed of in a normal manner.
Maintenance

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Limited Warranty
Aeron products are covered by 2-Year Limited Warranty, or a 90-Day Lim-
ited Warranty on vacuum tubes. This Limited Warranty initiates from the
date of purchase, and is limited to the original purchaser, or in the case of
demonstration equipment, limited to the original purchaser, or in the case
of demonstration equipment, limited to the balance of warranty remaining
after original shipment to the retailer or importer.
The authorized importing retailer or distributor has accepted the responsi-
bility for warranty of Aeron products sold by them. The specific terms and
remedies for fulfillment of the Limited Warranty may vary from country to
country. Warranty service should normally be obtained from the importing
retailer or distributor from whom the product was purchased.
In the unlikely event that technical service beyond the ability of the im-
porter is required, Aeron will fulfill the terms and conditions of the Limited
Warranty. Such product must be returned at the purchaser’s expense to
the Aeron factory, along with a photocopy of the dated purchase receipt
for the product, a written description of the problem(s) encountered, and
any information necessary for return shipment. The cost of return shipment
is the responsibility of the purchaser.

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AERON AP 990C Specifications:
European istribution
Audio4 branch of Stereoland—Bolzano—Bozen—ITALY
www.audio4.it - www.aeron-audio.it
Email: [email protected]t - [email protected]
The manufacturer herewith declares that the product is in conformity with
the provisions of the CE directive(s) including all applicable amendments.
Power Output: 50Wx2 (KT-88)
Frequency Response: 20Hz-50kHz (5W)
istortion: 0.1% (10W)
S/N Ratio (LINE): 86dB
Input Sensitivity: 300mV
Input Impedance: 80k ohms
Balanced Impedance: 95k ohms
MM Impedance: 7k ohms/68pF
MM Input Sensitivity: 3.5mV
S/N Ratio (Phono): 78dB
Output Impedance: ohms or 8 ohms
Max Power Consumption: 320W
Power Supply: AC115V/230V/50-60Hz
Tubes: xKT88, 2x12AX7, 2x6SN7
imensions: 30x350x180mm (LxWxH)
Weight: 30kg
Note:
Power tubes can be replaced by matched pairs of KT-100, KT-120, KT-150