SOLD! - 1962 JMI VOX AC15 Twin Fawn 2x12

SOLD! - 1962 JMI VOX AC15 Twin Fawn 2x12

€ 5.995,00Prijs

Original fawn tolex, grillcloth, cabinet, chassis, transformers, speakers, footswitch etc etc.

Rare amp in great condition!!

 

If an AC-30 was not in the budget for a young guitarist living in the 1960s, the AC-15 Twin was a good option.

 

The AC-15 Twin and AC-30 cabinets had the same external dimensions and both had two 12" speakers. Unlike the AC-30, which featured two Celestion Alnico Blues, the AC-15 Twin utilized two Goodmans speakers.

 

The AC-15 Twin used the original AC-15 circuit designed by Dick Denney. The heart of Vox tone comes from the power amp section, and three key design concepts were combined in the AC-15 power amp design to create the characteristic Vox sound.

 

Denney's design used two small bottle EL-84 power tubes to make the first component of the Vox signature tone. The EL-84 is a highly efficient tube. It was capable of producing 15 watts per push/pull pair at a relatively low circuit plate voltage of only about 350 volts. By comparison, EL-34 and 6L6GC output power tubes required plate voltages that approached 450 to 500 volts.

 

The efficiency of the EL-84 also had a "downside": EL-84 tubes were a bit more prone to distort due to their reduced "headroom." Simply stated, when pushed hard, the distortion level could creep up into the 7 percent area. This distortion was normally controlled by the incorporation of a circuit design called "negative feedback." Negative feedback sends a bit of the signal coming out of the amplifier back to the imput of the power amp. This not only cleans up the distortion, but removes some of the harmonics in the signal.

 

After listening tests, Dick Denney decided he preferred the harmonically rich tone of the AC-15 amp without negative feedback. He also liked the way the amp distorted when overdriven. And so do we!!!!!!!

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