The Harp Mic Shop

Item - BOG20PA

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This Bogen CHA20 is one of the Hottest 20 Watt tube amplifiers ever made for Blues Harp and they will outperform most 20 Watt amplifiers in terms of actual audible decibels of sound.

This Bogen CHA20A delivers a solid 20 Watts of Pure Tube Power with a nice pair of vintage 6V6 tubes. The stock CHA20  utilizes a pair of 6V6G Power Tubes and a pair of 12AX7 Preamplifier Tubes and it really puts out the sound. The power supply capacitors have been replaced and upgraded and with the upgrades this amp is even able to support a pair of 6L6G Power Tubes giving you even more tone variety.

This particular Bogen CHB-10A has been customized specifically to provide a Great Gritty Distorted Tone so often associated with Chicago Style Blues. The power supply has been inspected and the power supply capacitors have been replaced and upgraded as necessary. The values of the inter-stage coupling capacitors have been increased to pass more bottom end through the entire circuit. The 12AX7 tubes have been replaced with a 12AT7 tube in the v1 position and a 12AU7 tube in the V2 position.  This lowers the preamp gain and provides better control of the volume level to decrease feedback.

The amplifier comes with a 12AT7, a 12AU7, two 6V6GT Power Tubes and the 6AX5GT Rectifier Tube.  Also included are the two 12AX7 tubes which were originally in the amplifier and a pair of Soviet 6L6 tubes to provide a little variety in tone.

As you can see in the pictures, a 1/4” jack has been installed for the Microphone input and a 1/4" jack is also installed for the Phono input.  The Tone control and both volume controls are working perfectly. A 1/4” jack has been installed to provide a speaker connection.

The amplifier cabinet measures 14” x 8” x 6 1/2” and has a grounded power cord and fuse. The front panel has volume controls for both the Microphone and Phono Channels and has separate Bass and Treble Controls.  The original knobs were faded and discolored and have been replaced with vintage Chicken Head Knobs!

The 20 Watts of Raw Tube Power this amplifier delivers is sufficient for most small venues and is perfect for recording sessions. 

The amplifier is capable of pushing a pair or a quad of 10” or 12” speakers and supports loads of 4, 8 & 16 Ohms so that you can use nearly any variety of speakers with the amplifier.

The amplifier weighs just under 20 pounds so it's small and lightweight and easy to deal with. The cabinet is in good condition but does have some minor damage on the top and one side panel of the Cabinet from shipping damage as you can see in the pictures.

All electronic components are in excellent condition and any aging or damaged components have been replaced with reliable replacement parts.

This is an amplifier you can count on to work when you need it to!