Gurus BRIVIDO User Manual

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GURUS S.r.l.

Via Vittori, 181 – 48018 Faenza (RA) Italy

Tel/Fax [phone] – Internet: www.gurusamps.com – Mail: [e-mail]

BRIVIDO

Signature Cicognani Head 3Ch. - 100W

USER’S MANUAL

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2) INDEX

3) WHAT’S BRIVIDO / WARNINGS

4) TUBES / BLOCK DIAGRAM

5) FRONT & REAR CONTROLS

6) TECH SPECS

7) THE BRIVIDO OUTPUT STAGE

8) REMOTE SWITCHING DIAGRAM

9) TONE STACK FILTERS

10) NOTE

11) SAMPLE SETTINGS

12) SAMPLE SETTINGS

13) WARRANTY CONDITIONS

Index

"Art and technology can go hand in

hand" (L.DaVinci)

Inspired by the famous maxim of the Italian

genius, Gurus Amps not only compromises the

realization of his amps, choosing the best

materials and technology available, but also by an

excellent design, functionality and the image of its

products.

Gurus BRIVIDO is inspired by the design of some

Italian icons from the world of racing have made

unique the "Italian way" combining art and

technology.

"Gurus is not just a brand, it is a project, an idea,

a vision precisely. We can not think about the

future without remembering what was our past. "

We were born as a small company that built the

best that technology had to offer, always looking
for the best materials, the best components, to

achieve something that was going to fill the gap

that formed between what the market had to

offer and what it represented the real needs of

musicians.

It’s by the close contact with guitar players at all

levels, the size of "custom shop" ready to take

new needs, criticisms, suggestions, which over

the years has allowed us to create innovative

products.

Introduction

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TO REDUCE THE RISK OF ELECTRIC SHOCK

DO NOT REMOVE THIS COVER

DO NOT USE ANY TOOLS INSIDE

REFER TO QUALIFIED

SERVICE PERSONNEL

TO REDUCE THE RISK OF FIRE OR ELECTRIC

SHOCK DO NOT EXPOSE THIS EQUIPMENT

TO RAIN OR MOISTURE

BE SURE THAT THE ELECTRIC NETWORK POWER
SUPPLY VOLTAGE IS THE SAME INDICATED ON rear
PANEL OF YOUR TRITONE HEAD.

TURN ON THE AMP BY THE POWER SWITCH AND
WAIT 30 SECONDS TO GIVE TIME TO WARM UP
TUBES.

CH ECK THE CO RREC T CONN ECTI ON OF THE
EXTERNAL DEVICES (IF USED)

GUITAR-AMP CONNECTION BY PLUG GUITAR CABLE
INTO THE ”INSTRUMENT” JACK SOCKET

GURUS BRIVIDO HEAD is an Italian hand-built tube
guitar amplifier undergoing to strict control methods,
able to guarantee a lifetime use; in case of technical
problems, do not try to repair the amp by yourself.
Inside the equipment there are dangerous areas with
hi-current and hi-voltage. The product servicing must
be carried out by specialized technicians and
authorized by Gurus Amps.
Inside the equipment there are no parts for which the
adjustment is at user’s care.

Be sure to have correctly carried out all the
connections and to have read this simple and swift
instruction manual, before contacting the technical
service.

RISK OF ELECTRIC SHOCK

DO NOT OPEN

WARNING

Using rules

“BRIVIDO” is the first of a products range that
will be unified under the same concept.
“Brivido” take his name from the emotion we
felt on its first hearing.. we could translate it
as “Thrill” or “Shiver”, something you can feel
when music or tone are able to touch your
soul and expand your creativity.
We took inspiration from an idea of the 60’
era, where some crazy engineer designed
tube power modules for Juke-box and live
clubs. Made by few EL34 running in a very
higher voltage than any others.
Restoring many of these old modules, we
found it a very good idea to be applied in a
modern guitar amp, with some mods to
increase his performances and safety as well.
But this idea let us reach some of the most
important results of our career, creating
something can be defined as the “holy grail”
of guitar amps.
It works with just the double of dynamic range
of any other existing amp, and you can feel it
un de r yo ur fi ng er s. I t c a n g e n e ra te
unbelievable power by only 2 tubes, more
than 100W RMS, moreover, it sounds totally
in the same way at any volume level, offering
the best guitar tones you already know, but
with unexpected dynamic, touch response
and so easy to play.
And this is the aim that all manufacturers has
tried to achieve for many years.
We made it as a three channel amp head, to
let you try its incredible possibilities in every
application."
You wouldn’t believe the dynamic of a
“Brivido” until you'll not tried out one.

Introduction

Warning !!

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V1 12AX7/ECC83 (HI GRADE)
V2 12AX7/ECC83 (HI GRADE)
V3 12AX7/ECC83 (BALANCED TRIODES)
V4 12AX7/ECC83 (BALANCED TRIODES)
V5 12AX7/ECC83 (BALANCED TRIODES)
V6 EL34B/6CA7
V7 EL34B/6CA7

The output power stage is near to 800 Volt. Only
EL34B/6CA7 tubes are suitable for this amp.

TUBES POSITION:
Front view, from Right to Left V1-V7

About Tubes

As the Gurus BRIVIDO operates in power Class
AB Push/Pull configuration, it is needed to set the
BIAS when swapping power tubes, so it is strictly
recommended to be done by a technician.

The most common signs of run-down tubes could
be: excessive noise, hi microphonic, power loss,
loss of high frequencies, bad bottom end or/and
uncontrolled changes of the output volume.

Tubes Life is estimated to more than 3000 hours.
This depends by tube production quality.

Tubes Replacement

Block Diagram

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Front Panel

1)

Holiday/Rocking : amplifier turning on/off

2)

Waiting/Playing : Stand by.

3)

Presence: Presence control

4)

Solo: Solo function volume level

5)

Tone: EQ Control for Channel 1 Clean

6)

Ch1 Volume: Volume for Ch.1 Clean

7)

Ch.2 Gain: Gain control for Ch. 2 Crunch

8)

Ch.2 Volume: Volume control for Ch.2 Crunch

9)

Ch.3 Gain: Gain control for Ch.3 Lead

10)

Ch.3 Volume: Volume control for Ch.3 Lead

NB: Hold Switch 18, 19, 20 for two second to Mute the Amp.

MIDI PRESETS STORAGE:

With a midi pedalboard connected (Transmission channel settled as Omnimode)

-

select a preset

-

then select a channel pressing 1 or 2 times the Ch. Switches (17.18.19)

- now save it pressing the Store switch (16).
All preset are rewritable, don’t need to clean memory.

11) Bass: Bass For Chs. 2 and 3

12) Middle: Middle for Chs. 2 and 3

13) Treble: Treble for Chs. 2 and 3

14) Lo Input: input for low impedance use

15) HI input: MAIN input for normal use

16) Store: Press for save presets via midi*

17) Clean/Solo Switch ch.1/solo

18) Crunch/Solo Switch ch. 2/solo

19) Lead/Solo Switch ch. 3/solo

1

2356784

9

10

11

131215

17

18

Rear Panel

1)

Midi Thru: Midi out connection

2)

Midi IN: Midi Main input

3)

Remote Out: Ch. 3/solo (momentary)

4)

Remote Out: Ch. 2/solo (momentary)

5)

Remote Out: Ch. 1/solo (momentary)

6)

Fx Loop mode: UP Series/Down Parallel (50%)

7)

Return: Power In

8)

Send: Preamp Out

9)

Speaker 16Ohm: 16Ohm Speaker: mono jack
for connecting cabinet with the same impedance

10)

Sp e a k e r 8 O h m : m o n o j ac k fo r
connecting cabinet with same
impedance. If you wish to connect two
pa r a llel cab i n et 16Ohm t he total
impedance is considered 8Ohm.

11)

Spea ker 4Ohm: mono socket for
connecting the cabinet with the same
impedance. If you wish to connect two
par a lle l c abi n et 8O h m the t o ta l
impedance is considered 4Ohm.

12)

Mains Input: socket for connection to
the mains power, the plug contains a
slot for the fuse of power supply circuit.
In case of failure of a fuse, replace only
with same specs fuses

1

2

3

4

5

6

789

10

11

12

16

19

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Technical Specs.

CLASS “A/B" PUSH PULL 6CA7/EL34B TUBES

Operating Characteristics Two Tubes:

Supply voltage 800 / 400 volts
Common grid No. 2 resistor (without decoupling) 750 ohms
Grid No. 1 bias -39 volts
Grid No. 3 voltage 0 volts
Input voltage 0 - 23.4 volts (rms)
Load resistance, plate to plate 11,000 ohms
Plate supply voltage 800 volts
Plate voltage 775 volts
Grid No. 2 supply voltage 400 volts
Plate current 22 x 91mA
Grid No. 2 current 2 x 19 mA
Max. signal power output 100 Watts
Total harmonic distortion +/- 5 %
Temperature 197° celsius

Av. Tube lifetime 3000+ hours

Main Power: 100/110/230V - 50Hz
Power Consumption: 300W
Output Power: 100W RMS INTO 4/8/16 OHM
(19Vp TO 4 OHM - 28Vp TO 8 OHM - 39Vp TO 16 OHM)
Amplifier Class: A/B
Instrument input 1 impedance: < 1M OHM
Instrument input 2 impedance: < 100K OHM
Channels gain:
CH1 MAX 40db
CH2 MAX 80db
CH3 MAX 140db
Solo gain: MAX + 8db
Ch1 Tone Stack: HIGH SHELF 2500Hz (HI IMPEDANCE)
Ch 2/3 Tone Stack: BASS 110Hz - MIDDLE 780Hz - TREBLE 2500Hz (LO IMPEDANCE)
Presence: HIGH SHELF 5500Hz
Fixed Resonance (internal trim): +3db AT 110Hz
FX Loop:
Send Level: MAX 1Vpp AT <100K OHM
Return Level: MAX 1Vpp AT < 100K OHM
Serial/Parallel mode: PURE SERIAL OR 50% PARALLEL
Analog Footswitches outs: 3 X ON/ON Switches for all functions
Midi Storable Functions: CH1 - CH2 - CH3 - and Solo for each channels - Mute
Midi setting: OMNIMODE
Midi Phantom Power: 9VDC 500mA (PHANTOM PWR TO PIN 3)
Output Tubes: 2X6CA7/EL34B
Preamp Tubes: 5X12AX7B/ECC83
Power Fuse: 100/117V - 3,15A SLO-BLO
Internal LO Voltage Fuse: 3,15A SLO-BLO
Internal HT Voltage Fuse: 0.5A SLO-BLO
Dimensions: 540X240X200mm.
Weight: 15Kg.

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The BRIVIDO Output stage concept

The “Brivido” Technology is based on a
High Voltage level working Output
stage, this offer Bigger Dynamic, bigger
headroom, and higher performances so
n o t i c e a b l e a s to u c h r e s p o n s e .
Moreover, this technology includes a
Bias circuit that keeps stable the entire
output stage, with lower working
temperatures of power tubes, extending
their life.

So, Brivido in three words:

-

More Power from just 2 tubes.

-

More Dynamic & Headroom.

-

Better performances at any volume.

Dynamic Behavior:

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Analog Footswiches wiring

BRIVIDO can be managed by a standard Midi controller or via Analog Switching Systems.
Just connect 3 standard Jack/Jack cables to have full control of all 6 functions of Brivido,
according to following schematics. Be sure your Switching device supports Momentary mode.

CH1/Solo

CH2/Solo

CH3/Solo

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Filter Diagrams

CH1’S TONE:

It is a passive control that changes the EQ curve acting on the entire range of frequencies, is in fact easy to
note that by acting on the amount of high, at the same time you have a shift in the shape of the medium and
a sensitive intervention but very linear in the low, that are always rounded and focused.
The advantages of this kind of control, are to merge into a practical single potentiometer a true multi-band
filter, able to respond to requests that our ear tells us, without ever deviate too much from best sounds of
your amp.

TONE STACK:

A Traditional Bass, Middle, Treble tone stack is dedicated to dirty channels: 2 - 3
In the diagram, you can see how effective the controls are.

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Note:

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Sample Settings:

Ch.1 Clean: Arpeggio

Ch.1 Clean: Funky Rhythm

Ch.2 Edge: Low gain R’n’ Stones

Ch.2 Crunch: mid gain Legendary 1959

Ch.2 Crunch: Hi gain Brown Sound

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Sample Settings:

Ch.3 Lead: Heavy rock Rhythm

Ch.3 Lead: Modern Metal Rhythm

Ch.3 Lead: Soloing

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Gurus product warranty covers 2 years from date of purchase with the exception of moving mechanical parts such as foot switches,
speakers and handles which have a 1 year warranty. The valves, lights and cables are guaranteed for 3 months from the date of
purchase.
The warranty does not cover damage caused by accident, misuse and / or neglect, failure to comply with the instruction manual, repair
and attempted repair by personnel not authorized by Gurus Amps, any damage caused during transport and delivery, (claims must be
presented to the carrier); damage to any product that has been altered or on which it has been removed, defaced or altered serial
number; damage caused by faulty connections or connections to equipment failures and/or defective power cables.
Responsibility of Gurus Amps for any defective product is limited to repair or replacement of the product at our discretion.
The Gurus Amps not be liable for damages resulting from loss of use of the product, lost time operation interrupted by non-use of the
product, loss of business or any other damages or incidental, consequential or otherwise; damage in transit or damage caused by
inadequate packaging or of poor quality.

Assistance: Please contact us for information on how, where and when to ship the product. The repaired goods will be packed carefully
and we recommend not include any accessories such as cables, effects, manuals, etc. ..
Please attach a copy of the original receipt of purchase (invoice or receipt) together with a problem description and your personal data.

THE WARRANTY IS NOT VALID 'WITHOUT A COPY OF YOUR RECEIPT OF SALE CERTIFYING THAT

THE DATE OF PURCHASE.

The costs of labor and material guarantee shall be at Gurus Amps charge, not Shipment costs.

Terms of Warranty

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Gurus Amps reserves the right to change technical features or look of his products in any
moment without notice.This product is pursuant to European Directives 89/336EEC