KAHAYAN Proaudio 8x4 MIDI Selector User manual

8X4 SELECTOR
8 AMPLIFIERS/ 4 SPEAKER SELECTOR
OPERATOR'S MANUAL
Version 4.3
Avd. de la Estación 4, local bajo
Zarzalejo, Madrid 28293
España
[e-mail]
www.kahayan.es

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TABLE OF CONTENTS
IMPORTANT SAFETY INSTRUCTIONS…………………………………3
INTRODUCTION…………………………….……………………………..4
RECOMMENDATIONS………....…………..……………………………..5
SETUP…………………………....…………..……………………………..6
WARNING OF SETUP.………....…………..……………………………..7
Q&A……………...……………………………….………………...….…….8
SPECIFICATIONS & WARRANTY.……………………………...….…….9
CREDITS………………………………………………………….....………11

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IMPORTANT SAFETY INSTRUCTIONS
1. Read these instructions
2. Keep these instructions
3. Heed all warnings
4. Follow all instructions
5. Do not use this apparatus near water
6. Clean only with dry cloth
7. Install in accordance with the manufacturer's instructions
8. Do not install near any heat sources such as radiators, heat registers,
stoves, or other apparatus (including amplifiers) that produce heat
9. Protect the power cord from being walked on or pinched particularly at
plugs and the point where they exit from the apparatus
10. Unplug this apparatus during lightning storms or when unused for long
periods of time
11. Refer all servicing to qualified service personnel. Servicing is required when
the apparatus has been damaged in any way, such as power-supply cord or
plug is dam- aged, liquid has been spilled or objects have fallen into the
apparatus, the apparatus has been exposed to rain or moisture, does not
operate normally, or has been dropped

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INTRODUCTION
The Amplifier/Speaker Selector is a system which allows you to connect 8
amplifiers to 4 speakers, providing the possibility of easily selecting
combinations of amplifiers and speakers. Thus avoiding waste of time and
making work easier. Useful for studio recording as well as live performance.
Thanks to Kahayan 8x4 Selector we can change the amplifiers and speakers
with ony one bottom, that means, if everything is connected correctly and our
recommendations are followed (see page 5), you can link the amplifier that you
want with the speaker of choice with simple touches of the dial.
For more information visit: www.kahayan.es

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RECOMMENDATIONS
Listed below are the most important recommendations for the use of the
8x4 Selector:
1- To avoid any equipment failures its vital to connect to the 8x4 Selector the
following things: the instrument, the amplifier inputs, the amplifier outputs and
the speakers. The initial connection should be with the amplifiers turned off or
Stand by.
2- Once everything has been connected you can use the 8x4 Selector with
all the amplifiers permanently switched on. It’s not necessary to use the
Stand By mode each time that you want to change the amplifier.
3- In the case where some speaker outputs are not being used, be careful
not to select them to avoid the amplifiers functioning without being charged.
4- This Selector contains an input mute system and phantom charge for the
amplifiers which have not been selected.
5- We recommend, to avoid any possible ground noise (This is not mandatory
and may the type of amplifier configuration you use, you will not have ground
noise), that only one of the amplifiers is connected to the electric ground*.
Preferably the most powerful amplifier or that which has the highest
consumption. By doing this avoid hum noise caused by ground loops.
NOTE: That doesn´t mean that the other amplifiers are not connected to the
ground. They are connected through the Selector. See the folllowing chart:
NOTE: We recommend the use
of a lif grounding plug adapter
(see photo below) or amp cables
without the ground pin (see
photo below).
AMPLIFIER 1
(MOST POTENCIAL AND THE
ONLY ONE CONNECTED TO
THE ELECTRIC GROUND)
AMPLIFIERS 2,3 … 8
(NOT CONNECTED TO THE
ELECTRIC GROUND)
*This ground technique is very common in live performance setups and referenced in many
guitar electronic books, example: TUBE GUITAR AMPLIFIER ESSENTIALS by Gerald
Weber - Foreword by Joe Bonamassa.

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SETUP
The following diagram explains how to connect the equipment:
4 X SPEAKER
Jack instrument Cable
Jack charge Cable (speaker cable)
8 X AMPLIFIERS
Outputs Inputs
INSTRUMENTS (GUITAR)

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WARNING OF SETUP
Install in accordance with the manufacturer's instructions/manual because a
wrong setup could damage any unit of the setup including the selector:
Approved setup examples for 1 Amp/Spk:
Non-approved setup examples for 1 Amp/Spk:
For any alternative setup please contact us: www.kahayan.es
SIMPLE MODE
FULL MODE
Jack instrument cable
Jack speaker power cable
COMBO
SPEAKER
HEAD
SPEAKER
HEAD
1
SPEAKER
HEAD
NOTE: before unplug your guitar from
frontal selector panel input, mute
selector on pedal rig/frontal button
1
NOTE: In the case where one or some speaker outputs are
not being used, be careful not to select them to avoid the
amplifiers functioning without being charged.
1
1
1
1
2
1
1
1
1

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Q&A
Listed below are the most typical questions that we have received from the
users of the 8x4 Selector:
- Does the selector have an input buffer?
No, this unit is a transparent amp/speaker selector, with no active electronics
components in the signal path, just a very short high quality cable in the
instrument input.
- What impedance 8x4 selector uses? Can the 8x4 selector adjust the
amp impedance?
This is like a 'patchbay', you connect your amp with the speaker you want, we
don´t make adaptations. For example if you have an 8 ohm amp and you have
2 cabinets (16 and 8 ohm), you have to choose the 'correct' speaker.
- What guitar cable do you recommend? We don´t have a preferable brand
but the cables must have good quality. We have detected that a configuration
with no quality cables changes the sound, then users tends to think there is a
problem in our 8x4 selector. Then, changes the cables and recovers the
definition and sound quality.
-Can I put all my amp heads in ’tower’ configuration (One above the
other)? You can configure all your amp heads in the way you want but the
users must take attention of the position of the power transformer (connected
to the power grid) of the amps. Some amp brands put the power transformer in
the left side of the head, and others in the right side. If you combine this two
cases amp, probably the induction of this power transformer will affect to the
second amp and you could have some noise. We recommend put the same
head amps (transformer position) in one 'tower' and the others in a second
'tower'.
- If I turn off the 8x4 selector and amps are on, is there a problem? No,
because all the amps go directly to the internal phantom load in that case, and
all your amps will be loaded.

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SPECIFICATIONS
• 8 Amplifiers and 4 Speakers Selector
• 1 Jack instrument input
• 8 Jack instrument outputs to Amplifiers
• 8 Jack charge (speaker) imputs from Amplifiers
• 4 Jack charge (speaker) outputs to Speaker
• Max. Watt input from Amplifiers: 180W
• Power Supply: 220/110V and 50/60 Hz Consumption: 5W
• Weight: 4,5Kg
• Dimensions: 42x435x285 mm (Height/Width/Depth)
• The manufacturer reserves the right to change the technical
specification of the product without prior notice.
Note: As of serial number 298 there is no voltage selector in the rear panel:
-From serial 298 to 309 the voltage switching (110/230) is automatic.
-From serial 310 to 318 the voltage switching is internal, need to do an
internal reconnection. For more info please contact us.
-As of serial 319 the voltage switching is internal and located inside the unit
in the power supply board with a swichter.

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WARRANTY
These products are guaranteed for a period of two years from the date of
shipment to the end user for countries of the European Union. For other
countries, please refer to the law in effect.
During the warranty period Kahayan Pro-Audio will, at their discretion, either
repair or replace products which prove to be defective, provided that the
product is returned to an authorised Kahayan service facility. The warranty will
not cover shipping the unit back to the Kahayan service facility, unless the
customer determines otherwise with his dealer/distributor.
Defects caused by unauthorised modifications, accident, negligence or any
misuse are not covered by this warranty. For further information please contact
your dealer or the distributor in your country.

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NOTICE OF COPYRIGHT AND OWNERSHIP
All designs, circuit board artwork, front panel artwork, text contained herein
and therein, and all other intellectual material is the sole property of Pablo
Kahayan from Kahayan Audio. Unauthorized use, distribution, reproduction,
etc. is strictly prohibited. Kahayan intellectual property is protected by
international copyright laws. Violators will be prosecuted to the fullest extent of
all applicable laws.
Transfer of ownership of this unit neither confers nor implies any transfer of
ownership of the intellectual property, proprietary design, etc. contained
herein.
CREDITS
Concept: Pablo Kahayan
Written by: Pablo Kahayan and Luis del Toro
Edited by: Luis del Toro and Pablo Kahayan