Tube amplifiers

(y) Psi - Twin channel amplifier

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The Psi (Ψ) amplifier is a high-end two-channel combo amplifier designed around the classic 6Sl7/6188 octal triodes typical of  the 40's 50's, which were predecessors of the miniature noval 12AX... already a general rule in amplifiers from  the 60's. It is generally accepted,  that octal triodes have a denser, warmer and three-dimensional sound, although at the cost of lower gain and more intrinsic noise, but these drawbacks have been completely resolved in this amplifier. The two channels are clean but with different dynamic and tonal response. Channel 1 is derived from classic Fender with interactive tone circuitry and typical attenuated midrange response.  Channel 2 is a version of the alternate circuit developed by engineer EJ James in 1949 and later redefined by Baxandall; the tone controls in this circuit are more isolated and non-interactive, the midrange response is flat  and it only contains bass and treble control. The amplifiers derived from these circuits can be found in several manufacturers from the 60's and 70's, the most typical being Ampeg and Orange. The two channels have independent inputs and are actively mixed on one of the dual triodes. There is the option of using input 2 as a remote switch to change channels with a footswitch. This amp is the perfect choice for the demanding studio-oriented musician, the sound is refined, three-dimensional  Very low noise and super versatile, it can be played from chordal Jazz to rock depending on the channel.

 

 

 

 

 

 

 

 

 

It is feasible to built  a simplified single channel version of this amplifier. Same specifications but only one channel to choose from and WITHOUT the fixed bias/cathode bias option. CONTACT 

 

 

Specifications 

 

# Channel 1 Volume, Treble, Middle, Bass

# Channel 2 Volume, Treble, Bass

# Footswitch Channel 2 input option for  channel change (optional consult price)

# Filtered and regulated DC filament current for low noise in preamplifier octal tubes

# Spring reverb and tube circuitry

# headphone output

# Impedance selector 8 - 4 Ω

# External speaker output

# 50 watts in fixed bias mode, 38 in cathode bias mode

# Fixed bias / cathode bias selector on front panel

# Celestion speaker

# 5-year warranty on defective materials and construction (except tubes and speaker)

# Free annual review for the first five years

# JAN 6SL7/6188 octal preamp tubes

# JAN 6SL7/6188 on inverter and pair of 6L6GC Tungsol power tubes, possibility of mounting other types of valves  El34, 6550, KT66, KT88 (see price increase)

#Weight : 22Kg

#Dimensions (mm) :  height 510, width 515, depth 320

 

 

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