Quelqu'un connai?

Et tu veux vraiment utiliser les 2 baffles? Ce ne serait pas plus simple d'utiliser ton 2*12 en steréo? Avec un préamp par baffle? J'ai relu le manuel, il est pas indiqué s'il est possible de mixer des baffles aussi différentes en terme de puissance.

Sinon, ya un autre moyen (pour pas si cher) c'est d'en acheter un autre ampli en plus ^^.

J'avais payé le mien 70€ il y a deja quelques années ^^

Pour dépanner, un rappel du mode d'emploi (encore disponible sur le site rocktron http://www.rocktron.com/support/manuals_discontinued.php)

Although operation of the Velocity® 120 is simple once the proper connec-
tions have been made, attention to the following precautions is essential to protect
your equipment against failure and ensure the long life of your Velocity® amplifer.
Power Output/Speaker Load
The Velocity® 120 is capable of producing the following power output
levels into each of these loads:
Bridged (Mono)
4Ω load*   (Not Recommended)
8Ω load 120 watts
16Ω load 95 watts
Unbridged (Stereo)
4Ω load 60 watts
8Ω load 50 watts
16Ω load 30 watts
(with both channels driven)
* Note: Rocktron does not recommend using the Velocity 120 in bridged mode when
connected to a load of less than 8 ohms. However, using the Velocity 120 in
bridged mode with an 8 ohm load produces the same output level (120 watts)
as would be achieved with a 4 ohm load - therefore using a 4 ohm load would
provide no additional benefits.
!
Always be certain to use speakers or speaker cabinets capable of
withstanding the power provided in the above mentioned applications.
Rocktron is not responsible for speaker failure resulting from use of this
equipment.
!
Never connect 2 outputs of the amplifier to the same speaker. This
would be equivalent to shorting the outputs of the amplifier together
and would shut the unit down immediately.

Automatic Short Detection
A feature truly unique to the Velocity® 120 is its Automatic Short Detection
circuit. Typically, shorting the outputs of a high output power amplifier will cause
amplifier failure and severely damage internal components. The A.S.D. circuit in
he Velocity® 120 will automatically detect any shorts which may inadvertently
occur across the amplifier's outputs and immediately shut down the unit to protect
t against internal damage.
Should this condition occur, switch the unit off for approximately 10
seconds and make sure that the cords from the amplifier outputs are properly
connected. When the power is turned on again with the proper connections, the
amplifier will operate normally. It is important to note that two outputs from the
amplifier should never be connected to the same speaker, as this would be
equivalent to shorting the outputs together and will cause the unit to shut down.
In the unlikely event that the proper connections have been made and the
unit still shuts down, we strongly recommend that you first contact our Customer
Support Department at the phone or fax number shown on the back cover of this
manual before taking the unit to a dealer or repair shop for servicing.
Definition Control
It often becomes a problem when playing with other musicians that the
guitar can get "buried" under the other instruments and cannot be distinguished
easily. The front panel Definition control gives the effect of bringing the guitar out
of the cabinet so that it can be heard despite the other instruments. Although it does
not actually affect the volume of the amplifier, the Definition control can be
adjusted so that the guitar becomes more audible when playing with a band.
Turning the Definition Control fully counter-clockwise bypasses the defi-
nition circuit, while turning it fully clockwise provides maximum definition.

Output Power
(Unbridged)

60 watts per channel @ 4Ω (both channels driven)
50 watts per channel @ 8Ω (both channels driven)
30 watts per channel @ 16Ω (both channels driven)

(Bridged)

120 watts @ 8Ω
95 watts @ 16Ω

Maximum Input Level +22dBu
Maximum Output Level +30dBu
Maximum Gain 37dB
Noise Floor -81dB (referenced to 1 watt)
Dynamic Range over 100dB
Distortion
(Typical) .015% THD
Frequency Response ±1dB, 20Hz - 20KHz (Definition control OFF)
Current Consumption 450 watts, 3.75 amps @120VAC

Ok !

Bon et bien cette fois...c'est réglé !

Ne pouvant faire ce que j'avais envisagé, je vais essayer de faire au mieux !