Ampete 88 User manual
Owner's Manual 88 Switching System
Ampete
88
Owner's Manual
Ampete Engineering GbR
Gutenbergstrasse 48
50823 Cologne
Germany
on 49 (0) 221 55 94 118
ax 49 (0) 221 55 94 974
mail [email protected]om
web www.ampete.com
February 2017, Firmware Versions: 88S/88S-STUDIO V2.0, 88 V0.9
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Owner's Manual 88 Switching System
__________________________
Ampete Engineering Gb , 2017
Ampete is a registered trademark
copyright 2017, all rights reserved
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Owner's Manual 88 Switching System
We all...
... produce electronic waste! It's just a question o time!
We here at Ampete Engineering are not only consumers, like you yourselves, but also engineers o electronic
products that we want to place into a modern world. Here it looks at irst glance that everything has been
invented already. But demands are getting more re ined and speci ic by the day and as in the economics, the
sports- or even spiritual world, per ormance, utility and consistency depend on small changes and nuances
in improvements. In other words we are supposed to get better every day. This is not a one way street, it's a
huge responsibility in the other hands!
For us it means more than wanting a slice o the pie. It means to review every single product we design or
its added values, to anticipate the circumstance you put it into in order to ‚simply' be able to maintain it
everywhere it has been sold to.
Today our whole li e is determined by electronics, at home, on the road, at work or vacation, in
supermarkets, concert arenas or even in natural resorts.
Today in general electronics aren`t built any longer to last! They`re cheap.
For people rom the 70ies like us it is a turning point. We grew up in a world where an electronic device is
nothing short o a masterpiece. Today 90% o electronic applications are manu actured by using robots or
exploitation in countries where `global players` celebrate the abolition o workers protection and minimum
salaries. But it doesn’t end there.
A ter an expected li e cycle, more or less short, the cheap electronic waste is gonna be ‚disposed‘ o . Dispose
might suggest that components like housing, metal and synthetics will be recycled to ind their way back into
a product. But o course o ten this is not how it is done!
I you ever heard o 'toxic city' (and I don't mean the antastic album o a great band) you probably know
what we speaking o .
It might surprise you to read this in a manual or an electronic device.
We want to make sure you understand that by purchasing an Ampete Engineering Product you will get a
device in which we put all our passion, belie and knowledge and that you get a product in the tradition o
many great people be ore us, or whom electronics were and still are wonder ul masterpieces.
But you also purchased a little piece o responsibility. Maintain your Ampete Engineering Product – we will be
here to support you, we built this to survive… possibly even us.
In case you should be aced with any issue on any day at any place somewhere in the world, we are here as
you would expect us to be.
This is not a promise, it is our view o li e.
Thanks or letting us be a part in enabling your musical world.
Yours sincerely,
Ampete
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Owner's Manual 88 Switching System
Table of Contents
Foreword............................................................................... 3
Introduction........................................................................... 5
Switching System Example Setups........................................... 6
88S....................................................................................... 8
88S / 88S-STUDIO System Hook-Up........................................ 10
88S-STUDIO.......................................................................... 11
Using the 88S-STUDIO with or without the remote 88R................. 12
88R....................................................................................... 13
Troubleshooting..................................................................... 15
A word on impedances........................................................... 16
Dimensions............................................................................ 19
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Owner's Manual 88 Switching System
Introduction
Ampete Engineering 88 Amplifier & Cabinet Switching System
The „Ampete Engineering 88“ Switching System is designed to route several Guitar or Bass Ampli iers
to several Speaker Cabinets. It covers several needs, rom the demo purpose in Music Shops, Trade
Shows or workshops to signal routing and real time switching in Recording Studios or even live music
applications. For the irst time customers have the chance to choose their avourite under a bunch o
ampli iers as well as Manu acturers are able to compare a status o an amp development, prototype or
competitor models.
The „88“ product line consists o three di erent models which can be used as a stand alone unit (88S-
STUDIO) or be combined to a massive system o many many amps and cabinets... theoretical up to 99
each!
The whole series can be operated by a central unit as the 88R REMOTE or a MIDI capable device plus
in case o the 88S-STUDIO it can be operated via the unit(s) itsel at the ront panel.
88S: The „Shop“ Switcher (see page 7)
The 88S is typically used by Music Shops or Trade Shows or demoing purpose, where a central
operating unit is needed.
It's a 2-rack unit device giving the possibility to connect 8 amps and 8 cabinets. It has a bu ered
Instrument Input or a guitar or a bass that will be automatically routed to the amp currently selected.
As the 88S has no ront panel controls it can only be operated via the 88R remote control.
88S-STUDIO: The „Studio“ Switcher (see page 11)
The 88S-STUDIO is a 2-rack unit switcher giving the possibility to connect 8 amps and 8 cabinets. It
has a bu ered Instrument Input or a guitar or a bass that will be automatically routed to the amp
currently selected.
Other than the 88S it has ront panel controls to select an amp or up to two cabinets directly at the unit
itsel . There ore it can be used as a „Standalone“ switcher that does not need necessarily the 88R
remote to be operated.
The 88S-STUDIO can be interconnected with other 88S-STUDIO units to build a larger system without
the need o a remote control 88R.
88 : The emote (see page 13)
The 88R is the remote controller or the 88 Switching System. It has a numeric keypad or selecting an
amp or up to two cabinets. It is connected to the 88S, 88S-STUDIO, or a system containing both via a
CAT5 ethernet cable. The 88R is powered via CAT5.
The following page shows some examples of how the three different models can be
combined.
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Owner's Manual 88 Switching System
88S
Features
–8 ampli iers selectable
–8 speaker cabs selectable, up to 2 at a time
–optional Line out or driving external power ampli iers when running W/D/W systems
–bu ered and unbu ered inputs
–ampli ier and cabinet selection without loss in sound, dynamics or noise
–no switching noises
–no switching latency
–protection circuits to prevent ampli iers rom damage
–cascadable in conjunction with other 88S, 88R or 88S-STUDIO
Front Panel
1. INPUT – buffered instrument input
The input eatures an ultra transparent bu er ampli ier, which eeds the line bus with a low
impedance signal.
In case o cascading two or more 88S/88S STUDIO each input is equal and can be used to eed
the whole system. Please make sure not to use more than one input simultaneously as the
signals will be added but the inputs signal level will be decreased dramatically.
NOTE: Because the 88S/88S-STUDIO comes with the unique eature o cascading several units,
the LINE BUS is not grounded as long as no instrument is plugged into any o a units input.
Hence we recommend to keep an instrument connected to the system, whether the system
persists o only one or more 88S/88S STUDIO.
2. DISPLAY
The display shows the number / ID o the 88S/88S-STUDIO in the system.
That way the block o 8 amps / 8 cabs is identi ied:
ID1: Amp / Cab 1-8; ID2: Amp / Cab 9-16; ID3: Amp / Cab 17-24; ID4: Amp / Cab 25-32 etc.
The ID is con igured ex actory by DIP switches in the unit and should only be changed by
authorized personnel. In case an existing unit shall be expanded with one or more units, please
get in contact with us.
NOTE: Never use more than one 88S/88S-STUDIO with the same ID in one system.
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Owner's Manual 88 Switching System
ear Panel
1. EMOTE O P EVIOUS SWITCHE
RJ45 connector jack or data transmission. Use a standard CAT5 cable in case you
extend the system with our remote 88R or another 88S/88S-STUDIO with the next
lower ID.
2. FOLLOWING SWITCHE
RJ45 connector jack or data transmission. Use a standard CAT5 cable in case you
extend the system with another 88S/88S-STUDIO with the next higher ID.
NOTE: Never connect the jacks (3. REMOTE OR PREVIOUS SWITCHER) o two
88S/88S-STUDIO!
3. (optional) LINE OUT
The LINE OUT jack provides a line level signal o the currently selected amp or eeding
external e ects, power amps or others. It's not intended or mixers or inter aces as it is
not requency compensated.
NOTE: Even i you are using more cascaded 88S/88S-STUDIO units, only one LINE OUT
is necessary or ALL 8, 16, 24 etc. ampli iers.
4. SPK BUS
The speaker bus provides the speaker output signal coming rom the amps or urther
88S/88S-STUDIO units. That way it is achieved that an ampli ier connected to switcher
'X' can be played through a cabinet connected to switcher 'Y'. There or link the SPK BUS
OUT jack o the very irst 88S/88S-STUDIO to the SPK OUT IN jack o the next
88S/88S-STUDIO in the system and so on.
In case you've chosen one unit with the optional LINE OUT, con igure that particular
unit as the No. 1 in the whole system.
Make sure to use speaker cables only!
5. SPEAKE CABINET (1-8)
Connect your speaker cabinets here. No matter which cabinets you choose, rom 1x12“ to
4x12“ with every impedance everything is possible, but consider not to exceed the power
handling o the speaker cabinet to avoid any damage to the speakers and/or the ampli ier.
The 88S/88S-STUDIO does not compensate any impedance issues.
Make sure to use speaker cables only!
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Owner's Manual 88 Switching System
6. AMPS SPEAKE OUTPUT (1-8)
Connect one loudspeaker/cabinet/amp output o each ampli ier to one o the jacks 1-8. Be
aware that these jacks are NOT independent but they correspond to the number o AMP
INPUT jacks o your 88S/88S-STUDIO . The maximum power may not exceed 300W. Use
speaker cables only!
Make sure to use speaker cables only!
7. LINE BUS
Similar to the SPK BUS the LINE BUS provides the instrument signal coming rom one o the
INPUTs to every 88S/88S-STUDIO in the system and hence every connected ampli ier.
There or the LINE BUS OUT o the irst 88S/88S-STUDIO has to be connected to the LINE
BUS IN o the ollowing 88S/88S-STUDIO etc.
NOTE: You can use the LINE BUS IN as an unbu ered input when using external preamps.
Make sure to use high quality instrument cables only and be aware that the cable lengths
between the switchers in the system are summed.
8. AMPS INST UMENT INPUT
Connect one instrument input o each connected ampli ier to one o the jacks 1-8. Best i
you proceed the hook up amp by amp (unlike to at irst connecting 8 inputs, then the 8
outputs) to avoid mixing up in- and outputs o di erent ampli iers.
This is the most sensitive connection when setting up the 88S/88S-STUDIO, again make
sure to use high quality instrument cables!
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Owner's Manual 88 Switching System
88S-STUDIO
Features
–8 ampli iers selectable
–8 speaker cabs selectable, up to 2 at a time
–optional Line out or driving external power ampli iers when running W/D/W systems
–bu ered and unbu ered inputs
–ampli ier and cabinet selection without loss in sound, dynamics or noise
–no switching noises
–no switching latency
–protection circuits to prevent ampli iers rom damage
–ront panel switches or selecting ampli iers and cabinets
–cascadable in conjunction with other 88S, 88R or 88S-STUDIO
Front Panel
1. INPUT – buffered instrument input
The input eatures an ultra transparent bu er ampli ier, which eeds the line bus with a
low impedance signal.
In case o cascading two or more 88S/88S STUDIO each input is equal and can be used
to eed the whole system. Please make sure not to use more than one input
simultaneously as the signals will be added but the inputs signal level will be decreased
dramatically.
NOTE: Because the 88S/88S-STUDIO comes with the unique eature o cascading
several units, the LINE BUS is not grounded as long as no instrument is plugged into
any o a units input. Hence we recommend to keep an instrument connected to the
system, whether the system persists o only one or more 88S/88S STUDIO.
2. AMPS (1-8) – Amplifier selection switches
Select one o eight possible connected ampli iers by pushing the corresponding
illuminated switch. Surely only one amp can be selected at a time. The remaining 7
amps will not be eeded with an input signal and are connected to an internal load to
prevent them rom any damage.
NOTE: A cabinet has to be chosen irst by pressing the corresponding ront panel CABS
switch.
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Owner's Manual 88 Switching System
3. CABS (1-8) – Cabinet selection switches
Select up to two cabinets at the same time by pushing the corresponding illuminated
switch(es).
A CABS button can only be selected with a speaker cabinet hooked up to the
corresponding SPEAKER CABINETS jack. Thereby the 88S/88S-STUDIO not only controls
i a plug is connected to the SPEAKER CABINETS jack, but also the attached load or its
impedance. A low impedance is interpreted as a speaker cabinet, a high impedance
could be a non connected cable, a de ective speaker cable or even a speaker in orm o
a ruptured speaker coil etc. In that case the 88S/88S-STUDIO would re use the
selection and state an 'n.c.' in the display or 'no connection'. This way the 88S/88S-
STUDIO prevents your ampli ier rom damage because o running without a load. The
display will state an error status (Er).
4. Display
The display shows the number / ID o the 88S/88S-STUDIO in the system. That way the
block o 8 amps / 8 cabs is identi ied.
ID1: Amp / Cab 1-8; ID2: Amp / Cab 9-16; ID3: Amp / Cab 17-24; ID4: Amp / Cab 25-
32 etc.
The ID is con igured ex actory by DIP switches in the unit and should only be changed
by authorized personnel. In case an existing unit shall be expanded with one or more
units, please get in contact with us.
NOTE: Never use more than one 88S/88S-STUDIO with the same ID in one system.
ear Panel
The Rear Panel is exactly the same as or 88S, please see page no. 8
Using the 88S-STUDIO with or without the remote 88
The 88S-STUDIO was designed a ter many customer's wish to switch between 8 amps and cabs but
without the need or an extra remote control. To achieve that, we wanted to bring the „standalone“
eature o the 444 to the 88S by adding ront panel controls.
But why not take it one step urther? The 88S-STUDIO can not only be used as a standalone 8x8 amp
switcher, but it can also be a part o an expandable system. It can be combined with additional 88S-
STUDIO units to build 16x16 or 24x24 system with still no need or a remote control.
You are ree to add an 88R to your system later, which gives you the opportunity to remote control your
whole amp rack rom your desktop right next to your computer mouse!
You will still have the visual eedback o the 88S-STUDIO's ront panel LEDs in your rack.
Any system o 88S-STUDIO and 88R can also be expanded by adding 88S units.
System Hook-up
please see page no. 10
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Owner's Manual 88 Switching System
88R
Features
–numeric keypad
–three double displays or displaying system status
–powered via CAT5
–works with any standard CAT5 cable
–„A/B“ and „ALL OFF“ unction
–ootswitch jack or A/B unction
–MIDI IN / MIDI THRU
Using the 88
The 88R remote has no power on/o switch. It is powered via the CAT5 cable connection to the irst
88S or 88S-STUDIO switcher in the system, and automatically powers up when connected.
(The display shows 'boot' or 2 seconds)
To adress an amp or a cabinet simply dial its number on the keypad. During this process the three
displays will lash and show the number entered. You can enter 1-digit or 2-digit numbers.
To con irm the number, press one o the three „ENTER“ buttons that correspond to AMP1, CAB1 or
CAB2.
I the number is not con irmed within a ew seconds the display will return to showing the system
status.
Note that or sa ety reasons the system does not allow you to select an amp without selecting a cabinet
irst. (see „Error Messages“ below)
I the remote is connected to a 88S/88S-STUDIO system that is already in use, the 88R will update the
system status display with the next switching process.
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Owner's Manual 88 Switching System
Error Messages
I any errors occur during the operation o the 88 system, the 88R displays will show error messages
or two seconds be ore returning to the system status.
1. 'n.c' (not connected) displayed at CAB1 or CAB2: This means that you tried to activate a cabinet
that is not plugged in
2. 'no Cab' shown over the three displays: This means that you tried to activate an amp be ore
selecting a cabinet. Always select a cabinet irst!
3. 'n.c' (not connected) shown in all o the three displays: This means that a number was dialed
that is not available in the system. For example i your system has two 88S and you tried to
activate amp number 17.
A/B and Footswitch
The A/B unction toggles between the last and the current system state. The A/B unction can also be
activated via a latching ootswitch connected to the „Footswitch“ jack.
ALL OFF
The „ALL OFF“ key unroutes all ampli ers and cabinets rom the system.
MIDI
The 88R eatures MIDI IN and MIDI OUT/THRU connectivity.
At this point o the irmware version it is only possible to switch between amps via program change on
MIDI Channel 1: PC 1 selects AMP1, PC 2 selects AMP2 and so on.
NOTE: You will have to select a cabinet irst via the 88R keypad!
An internal jumper can select between MIDI OUT or THRU or uture developments o the irmware.
The 88R is set to MIDI THRU by actory de ault.
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Owner's Manual 88 Switching System
Troubleshooting
Problem: No signal when an amplifier is chosen.
Make sure all amp inputs and speaker outputs are properly connected. Never mix amp
in- and outputs to di erent ampli iers!
Problem: No amp can be selected.
Check i a cabinet has been selected irst.
Problem: No cabinet can be selected.
Check i the chosen cabinet and cable is connected properly.
Also check the cable and/or speakers or any de ects.
Problem: No function when switching via MIDI on 88
Check i you are sending on MIDI channel 1 (see page 14)
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Owner's Manual 88 Switching System
A word on impedances
When it comes to impedances and matching o valve ampli iers and speaker cabinets, there have been
written a lot o words and there have been told many opinions, myths and belie s. And as it is so o ten
in our world, all o them are in between the truth and the untruth. Some more, some less. Don't expect
mine to be the only truth! But I give you some arguments on hand, why it is not necessary to match
your amp and cabinet and why your ampli ier will not get damaged when the load does not match the
impedance switch setting.
Let's start with one o the most o ten heard opinions. Some claim that a mismatch between ampli ier
and cabinet causes the valves to wear out quicker or can cause damage to the output trans ormer
and/or valves while at the same time advertising their ampli iers to work with any kind o valves,
doesn't matter i EL34, 6L6, KT66, KT88 etc.
Don't get me wrong that this is not possible, but the matching between ampli ier and cabinet isn't
isolated on the secondary winding o the output trans ormer and the speaker. It's an interaction
between valves, primary winding o the output trans ormer, secondary winding o the output
trans ormer and speaker. It starts with a certain impedance each valve type has and which would
require (i we go on with the argumentation) a speci ic primary winding and thus again an impedance
o the output trans ormer to be 'matched'. The output trans ormer itsel not only trans orms the
voltage, it also trans orms the impedance. It continues to the output trans ormers secondary winding
(with another you know what) and ends with the speaker (sorry, but yes...).
As mentioned above, this is not a one way street, it's an interaction, which means the speaker
in luences the power ampli ier and the power ampli ier in luences the speaker. Surely this is not a linear
process, it is dependend on requency, power or wattage, electric and even mechanic speaker
speci ications.
And i this wouldn't be enough, remember that it's called impedance because it alters with the
requency... i you have ever seen the impedance curves o a speaker you know what that means.
There are several ways to 'mismatch', using di erent speaker impedances is only one possibility.
Di erent valve types or 2 instead o 4 valves are others. But none o them causes the power amp,
valves or output trans ormers to ail.
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Owner's Manual 88 Switching System
The diagram below shows some simple measurements (in that particular case taken with our Amp
TWO, a 110 Hz, 150mV sine wave, which is similar to the 'A' strings irst harmonic o a Humbucker
guitar). The amp impedance switch has been set to either 4 (blue color), 8 (orange) and 16 (yellow)
Ohm and in every o these settings a reactive load o 2, 4, 8 and 16 Ohm has been attached to the
power amp. Let's point out only the two essential characters.
1. When the amp impedance switch and cabinet load are matched, the wattage is nearly identical
in either 4, 8 or 16 Ohm case;
2. The higher the load the higher the wattage, or equivalent the lower the load, the lower the
wattage.
Is it as simple as that? Yes and No.
No, as mentioned above this is not as linear as it looks at irst glance as it is dependend rom several
parameters.
Yes, because - and this is the main act or all the 444 users – it will never be the other way round. The
Power will not increase when the load impedance is lower than the chosen amp output impedance
(surely as long as we are talking about valve driven ampli iers). And not only the wattage will not
increase, also the voltage - primary and secondary – decreases with a lower load.
For those who are interested, the current increases. On the primary side it does not exceed the
maximum current lowing when the amp impedance switch and load are set to its minimum position
(most o ten 4Ohm). The current lowing on the secondary side increases slightly about 10-15%.
The 444 is capable o switching 1 or 2 cabinets to any o the connected ampli iers. That means, the
load to the ampli iers output will change when the second cabinet is assigned to it. Let's assume your
ampli iers impedance switch is set to 16 Ohm, you run a single 16 Ohm cabinet with your ampli ier and
you add a second 16 Ohm cabinet, then the total load will change to 8 Ohm.
Now re er to the diagram and you see the power o the ampli ier drops.
17
0 2 4 6 8 10 12 14 16 18
0
5
10
15
20
25
Wattage dependent from load
Amp Imp switch 4 Ohm
Amp Imp switch 8 Ohm
Amp Imp switch 16 Ohm
Cabinet
Load / Ohm
Power / Watt
Owner's Manual 88 Switching System
But even i the power decreases by almost one third compared to a matching load, the subjective
impression will be the volume is nearly the same (as long as the phases o the speaker cabinets are the
same). This is simply because more speakers are now driven by the ampli ier. You will notice a slightly
di erent eel, which is caused by a di erent damping actor the power amp o your ampli ier 'sees'.
Hereby a lower impedance rom your cabinet will eel more 'loose', a higher impedance will give you a
more 'tight' eeling. There is a simple reason or that. As seen be ore the higher impedance causes the
ampli ier to emit more power, more 'headroom'. Because the bass requencies require more power than
the higher requencies, it can be ampli ied more accurate, more 'tight' as it's o ten called. The dynamic
does not drop when especially palm muted low strings are hitted. In contrast there's a natural sag with
the lower impedance because o the lowered power.
But don't expect these changes to be drastically, we are talking about nuances in sound. This will be
even more hard to notice because the number o speakers has changed.
Having said that, we recommend to undermatch the cabinet load when using 2 cabinets at the same
time.
–one or two 16 Ohm Cabinets (=8 Ohm) Impedance switch 16 Ohm→
–one or two 8 Ohm Cabinets (=4 Ohm) Impedance switch 8 Ohm→
–one or two 4 Ohm Cabinets (=2 Ohm) Impedance switch 4 Ohm→
It is also possible to mix cabinets with di erent impedances, you only have to be aware that the power
to the cabinets will be di erent as well, to be precise it will be twice as high at the cabinet with hal the
impedance.
–one 16 and one 8 Ohm Cabinet (=5,33 Ohm) Impedance switch 16 Ohm→
–one 8 and one 4 Ohm Cabinet (= 2,66 Ohm) Impedance switch 8 Ohm→
In any case do not exceed the power handling o the speaker cabinet! Be aware o , that the setting o
your volume control is not an indicator or the power your ampli ier emits.
This is just a rough overview on the interaction between a valve driven power ampli ier and a
loudspeaker. Believe me, that process is ar too complex to put it in such a manual, and to be honest in
it's entirity it would exceed my knowledge. And even i the era o valves is long gone, this is why some
very ew people - including me - are still researching on it.
… and we keep you in ormed!
18
Owner's Manual 88 Switching System
_______________________________________________________________
88S / 88S-STUDIO
Dimensions Front Panel: W 17,2“ (438mm), H 3,5“ (88mm), D 8,8“ (223mm)
Front Panel: W 19“ (482mm)
Weight 10 lbs (4,5kg)
Power consumption 10W max.
_______________________________________________________________
_______________________________________________________________
88
Dimensions W 6,7“ (170mm), H 2,1“ (54mm), D 7,1“ (180mm)
Weight 2 lbs (1kg)
_______________________________________________________________
Ampete Engineering reserves the right to change speci ications, whether it's technical, dimensional or in the owner's manual.
Fender, Marshall, Vox, RJM or other brands or models are registered trademarks to their respective holders. Ampete Engineering isn't a iliated with them in any way.
__________________________
Ampete Engineering Gb , 2017
Ampete is a registered trademark
copyright 2017, all rights reserved
19
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