A3-Mini Stepped Attenuator
The standard A3 36-position stepped attenuator is 9 inches long, whereas this new A3 Mini is only 5.8 inches wide, but is otherwise identical. Where the resistors lay flat against the standard A3 PCB, the resistors stand perpendicular to the PCB on the new A3 Mini attenuator.
The Trim-1 stepped attenuator offers 11 positions and can viewed as high-quality replacement for a potentiometer. In other words, it can be used in non-audio as well as audio applications. A Trim-1 can even be used as a balance control of sorts.
The A5 stereo stepped attenuator kit includes two shorting rotary switches (2-pol/6-pos) and one USA-made extra-thick (0.94"), high-quality PCB, with 2oz copper traces and two side solder mask and silkscreen.
The M1 stepped attenuator combines both series and ladder stepped attenuators into a single functional attenuator. The ladder attenuator's job is to provide six fine steps of attenuation (-1dB per step); the series attenuator, eleven coarse steps of attenuation (-6dB per step).
The BM-1 balanced mono stepped attenuator combines both series and shunt stepped attenuators into a single functional attenuator. The shunt attenuator's job is to provide eleven coarse steps of attenuation (-6dB per step); the series attenuator, six fine steps of attenuation (-1dB per step), for a total attenuation of -65dB.
Like its unbalanced predecessor, this attenuator offers 36 steps of attenuation for two channels of balanced signal. The center rotary switch controls both channels and presents coarse decrements, while the two flanking switches afford fine volume decrements for each channel.
The TCJ Attenuator A3 is an interesting design: a hybrid attenuator that uses both series and ladder attenuators to yield the best compromise between flexibility, performance, and cost.
The three positions are: all transformers off, transformer 1 on and transformer 2 off, and both transformers on. With this setup, you can turn on the heater transformer first, so the tubes are given a chance to heat up, which will create an electron cloud over the cathodes, protecting them from the B+ voltage.
The Select-4 switch and PCB makes wiring up a line stage amplifier easier. Select up to six stereo inputs.
1.4 by 2 inch, PCBs that hold a single rotary switch and nothing else, other than termination pads for hookup lead. The Select-2 selector switch assembly accepts three stereo inputs, with both the hot and grounds of each signal source to be selected. So if a signal source, say a CD player, is not selected, neither its outputs or grounds make any connection to the line-stage amplifier.
The capacitor selector makes wiring up an Aikido board an easy task, as the two coupling capacitor outputs from each channel attach to the small PCB and the two outputs leaving the switch allow choosing between coupling capacitors C1 or C2 or both C1 and C2 in parallel.
With a balanced system, we can easily flip the phase of the signal with the GlassWare Select-Phase switch and PCB. I get a lot of e-mail asking if I believe in phase. In other words, do I believe that we can hear the difference that phase reversal makes? I do. I have performed many experiments with phase and I have found that the difference is obvious, if one important stipulation is followed: you must pause at silence in between phase reversals. It doesn't take long, maybe a second or two, but this brief pause gives the ear and brain a chance to readjust to the change in phase. On the other hand, with no pause (and a two-position toggle switch), no difference can be heard with mad flipping back and forth. The Select-Phase switch has mute at the center in between phases.
New and Improved TCJ Stepped Attenuator Kit