Thermionic Culture THE SOLO VULTURE User Manual

THERMIONIC

CULTURE

TS VHE OLO ULTURE

valve distortion unit

OPERATING MANUAL

WARNING

Do not take this unit seriously. The Solo Vulture is a ‘fun’ effects
unit and has been designed for maximum pleasure!

However, for your personal safety, please read this operating
manual and this warning thoroughly before using the equipment.

This unit must be installed in such a manner that operator access
to the mains plug is maintained. Where the product is to be rack
mounted, this may be achieved by having access to the
disconnection device for the whole rack.

To reduce the risk of electric shock, it is essential that the unit is
disconnected from the mains supply before removing the cover.

Please also note that the power supply capacitors within this unit
can remain charged even after the mains supply has been
disconnected. It is essential that these capacitors are discharged
after the mains supply has been disconnected and the covers
have been removed.

In the event that this unit has been dropped or has suffered an
impact, an electrical safety test must be carried out before
reconnection to the mains supply.

This equipment is not intended for use in explosion hazard
environments. It must be used and stored in studio conditions,
such that the ambient relative humidity does not exceed 80%, nor
is the temperature to be allowed to drop to a level, which would
cause dew point to be reached.

Please ensure that adequate ventilation is provided and that the
ventilation slots are not obstructed. When rack mounting this
equipment, a fan may be required to provide sufficient airflow.

©Thermionic Culture Ltd, May 2012 1

CONTENTS

Section Page
1 Introduction 3

2 Controls & Meters 4

2.1 Input gain 4

2.2 Drive 4

2.3 Presences 4

2.4 Bias (and meter use) 4

2.5 Distortion Type switch 5

2.6 Mid Lift 5

2.7 LPF (Low Pass Filter) 5

2.8 Dirty and Clean output level controls 6

3 Operational Hints 7
4 Inputs and Outputs 8
5 Servicing and Maintenance 9

5.1 Valves 9

5.2 Operating voltage / Fuse 9

6 Specification 10

6.1 Clean channel 10

6.2 Dirty channel 10

6.3 Impedance 10

© Thermionic Culture Ltd, May 2012 2

1 Introduction

The Solo Vulture is a version of the classic 2 channel Culture
Vulture.

It’s a mono unit, but it’s much more than half of a Culture
Vulture.

Designed initially for guitar use, it’s very much at home with any
instrument(s), including keyboards, bass, violin, cello, brass and
even percussion.

It has higher gain and will amplify any electric instrument to get
full effect from this new circuit. The rear input is “semi floating”
so no unwanted (solid state) distortion will be added if a
balanced source is plugged in. This input has the same gain as
the DI, but is cut out when a jack is plugged into the DI input.

The same “distortion” valve is employed (6AS6 type). The
features found only in the “Anniversary” edition are available
along with a Presence switch, extra top lift pre-distortion at high
gain settings, and a 4 position low pass filter to reduce
unwanted harmonics. The special Hi Q mid lift feature is
available on all Distortion settings.

The circuit comprises 2 switchable channels, CLEAN & DIRTY.
The Clean channel is there for comparison with the Dirty signal
and the volumes of both can be controlled by the 2 controls
under the meter. Switching between the channels is totally silent
yet solid-state free, using light dependent resistors. This means
that the true Thermionic Valve “warm” sound is fully retained.

The Clean channel can also be used for gentle (2
distortion, though not on low level inputs.

nd

harmonic)

© Thermionic Culture Ltd, May 2012 3

2 Controls & Meters

2.1 Input gain

This switch varies the amount of gain in the 1

Solo Vulture. The figures, 5 to 35 dB, represent the gain

available to the Clean channel with the Clean output
control set at 8, so 5 dB more gain is actually available.
The first stage goes straight to the output stage when
Clean is switched in. When Dirty is selected, a top lift is
introduced in the 25 & 35 dB positions to give more “bite”.

2.2 Drive

This control varies the amount of signal fed to the 6AS6
type distortion valve. The higher it’s set the more gain and
distortion.

2.3 Presence

A 3 position switch. 1 “flat”, 2 a broad mid lift favouring the
upper mid range, 3 a broader mid lift with more boost.

2,4 Bias (and meter use)

This control varies the current through the 6AS6 type valve
by changing the positive voltage on its cathode. The actual
current is shown on the milliameter. When the Vulture is
starved of current the sound appears thinner and when
over-fed it becomes warmer and fatter. The typical setting
is 0.25 – 0.3 mA, which also gives lowest distortion. When

the Solo Vulture is pushed to heavy distortion the meter will

twitch.

N.B. The Bias control in naturally noisy in operation, but

should be quiet when set.

st

stage of the

© Thermionic Culture Ltd, May 2012 4

2.5 Distortion Type switch

This switch controls the configuration of the special 6AS6
type valve:

T: The valve is a Triode, which is smoothest, all 2

harmonic distortion.

P: It becomes a natural Pentode, which has higher

gain, especially with low bias, and some odd
harmonics come in giving a more “aggressive”
sound. This setting is favoured by most users.

SQ1: The SQ settings take advantage of the unusual valve

for effects. SQ1 is similar to P but when the valve is
pushed it distorts rather more, compresses then
over-compresses so much so that it reaches cut-off
point. Use with caution.

SQ2: The configuration is now more Tetrode than Pentode

and is a seriously distorting setting. Can be quite
fun. An octave may be added at high bias settings.
(also with SQ1). Needs more “Dirty” output gain.

2.6 Mid Lift

This switches in a very high “Q” tuned circuit which is
designed to boost frequencies that relate to musical
chords. It can be very effective when it’s switched to the
key of a song and can really make a guitar or other

instrument stand out in a mix. It’s most effective in P

distortion setting with medium bias.

2.7 LPF (Low Pass Filter)

This is a sharp (12dB/octave) filter to remove unwanted
high frequencies:

nd

© Thermionic Culture Ltd, May 2012 5

15kHz subtly takes off a little HF “tizz”
9 kHz for unwanted “hard” distortion effects
4 kHz is a pretty drastic setting. Can give a warm “valvy”

sound.

2.8 Dirty and Clean output level controls

These 2 controls set the sound level sent to the output
valve. The channels can be selected by the toggle switch
to the right or a foot pedal. Switching is totally silent.

When using the Solo Vulture, set the 2 controls to get a

comparison between Clean and Dirty, also an adequate
output level. The headroom of this unit is higher than that
of the standard Culture Vulture.

For T & P distortion settings, the Dirty will be set much
lower than Clean but in the SQ settings it will be (possibly)

higher.

© Thermionic Culture Ltd, May 2012 6

3 Operational Hints

It’s impossible to list all the options here, as it’s up to the user to
find their own best settings.

Just a few guide lines:

For electric guitar, use higher bias settings for rhythm and lower
for solo as you get a more open, warmer sound. Turn up the
Presence and use the LPF for a very “middly” sound. Tune the
Mid Lift to the key of the song to be most effective.

If playing live then ideally use the Solo Vulture as a pre-amp for

a power amplifier – or even in the effects loop. Of course use
the low level output for these purposes.

When mixing, the Mid Lift is really useful at lower distortion
settings and 0.2 – 0.3 on the meter when this control acts more
dynamically, so the instrument can jump out of the mix without

using too much space. Use in P mode for most effect. Tune to
the right frequency.

© Thermionic Culture Ltd, May 2012 7

4 Inputs & Outputs

There are 2 input and 2 output sockets, all standard TRS jacks.

The Line Input at the rear is “semi floating” so that it can be
used with balanced signals without quality loss. The front DI
input is unbalanced.

The 2 outputs are both unbalanced with the Lo 20dB (approx.)
below the Hi for use in re-amping, etc.

© Thermionic Culture Ltd, May 2012 8

5 Servicing & Maintenance

The unit comes with a 12 month warranty, including valves. In
the event of a fault developing within the warranty period it must
be returned to the dealer who sold it, or to our factory at

purchaser’s expense, otherwise the warranty is invalidated.

5.1 Valves

One of the most common faults is a valve failure and we
may be able to be able to diagnose this by ‘phone or email
so contact our Technical Support department first –
[e-mail].

Valve complement (near equivalents in brackets):

Input - ECC83 (12AX7, 7025);
Distortion - 5725 (6AS6, M8196, CV4011);
Output - 5965 (12AV7)

New valves can be supplied by Thermionic Culture Ltd.

5.2 Operating voltage / Fuse

The Solo Vulture is switch selectable to operate from either
230V or 115V 50/60Hz AC mains supply.

NOTE: Mains fuses may be replaced in accordance with
the following table:

Operating Voltage Fuse Rating

115V T500mA 20mm type
230V T250mA 20mm type

© Thermionic Culture Ltd, May 2012 9

6 Specification

6.1 Clean channel

Measurements with Clean gain at max, 10kΩ load, 5dB
gain.

Distortion (THD) <0.1% (+4dBu ouput level)
Frequency response 35Hz to 20kHz (+0, -2dB)
Max. O/P Level (MOL) +23dBu, 2% distortion
Noise (30kHz filter) 98dB below MOL
Max gain (35dB setting) 40dB

6.2 Dirty channel

Measurements with Dirty gain at 8, 10kΩ load, bias control
at 5.5, P selected, controls at "flat".

Distortion (THD) <1% (+4dBu ouput level)
Frequency response 60Hz to 15kHz (+0, -2dB)
Max. O/P Level (MOL) +24dBu, 20% distortion
Noise (30kHz filter) 88dB below MOL
Max gain (35dB setting) >75dB
Max. possible distortion >97%

6.3 Impedances

Both inputs: 50kΩ
Hi Output: 240Ω
Lo output: 1.7kΩ

© Thermionic Culture Ltd, May 2012 10

15

10

Gain (dBr)

-5

-10

Solo Vulture - Frequency Response Curves

Flat Clean 5dB

5

0

Flat Dirty 5dB
Flat Dirty 25dB
LPF4
LPF9
LPF15
Pres Full
Pres Half
Mid Lift 0.5
Mid Lift 0.63
Mid Lift 0.85
Mid Lift 1.1
Mid Lift 1.6

-15

f (kHz)

01

2011.004.0

Thermionic Culture Ltd., Harlow, Essex, UK

Tel: [phone] Fax: [phone]

© Thermionic Culture Ltd, May 2012. Printed in UK.