Doing Things Wrong

Silvertone 1457 Guitar & Amp (3/5)

The attenuator circuit for both the 1457 and 1472 amps

The LPad is the first stage and does most of the work, the fixed second stage can be switched in for even more quiet. The 50 watt LPad should be sufficient for at least a 20 watt amp. The capacitors suppress audible pops from the switches.

For the circuit above, the 1457 amp is nominally 5 watts at 4 ohms, while the 1472 is 10 watts at 8 ohms. The idea is to bleed off power while maintaining a constant impedance to the amp. This lets you get nice natural tube distortion without the neighbors calling the police. For these small amps, heat dissipation is not a problem.

Each circuit has two options for the fixed second stage, one for 12db and one for 20db - choose one. The values of the fixed resistors depend on the impedance of the speaker. For simplicity, just omit the second stage, it is not necessary, I was just experimenting.

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I took a drive over to Harbor Freight - purveyor of fine {sarcasm} Chinese tools & hardware - and picked up this little drill press. With a coupon, it cost me just over fifty bucks. This is not what I would call a good drill press, in fact, it is pretty crappy. The base and the table are stamped, not forged, and small. The quill travel is a measly two inches, parts that should be steel are aluminum, parts that should be aluminum are plastic, vibration is excessive, and the 3/8" chuck has a disconcerting wobble to it. I knew all that when I bought it, and I never would have if I did not already have a much better one, or at least a decent one. What I wanted from this drill press is small size and lightweight, so I can add it to my inside workstation, and not have to leave the heat/ac to go drill a hole in the garage. This press weighs well under 40 pounds and doesn't take up too much space on my inside workbench. My 'good' drill press is not something you'd want to move around a lot.

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