Avant Electronics feels that the 6072a tube that is installed in the microphone is the best balanced tube by far for the majority of work with the CV-12, but we have provided two additional tubes, the ECC81 and ECC83 for different tube "voicings". Starting with the 6072a tube each tube has an increasingly “hotter” output, thus distorting the transformer sooner.  Many of you might never require these tubes but if you require an unconditionally aggressive, distorted vocal track or have an exceptionally mellow female vocalist; then you might find them useful.  This is all part of the Avant Electronics “Affordable Excellence” motto to provide the best to our customers!

 Nevertheless, changing tubes is not meant to be done frequently, as the repeated stress on the wiring and solder points over time can increase the chances of damage to the microphone.  One careful listen to each tube should determine your needs for future recordings.  We offer this great feature so you can “hot rod” the CV-12 but YOU MUST BE CAREFUL!  Changing tubes can be done safely, if you precisely follow the instructions and take your time.

Rough handling is not covered under warranty so all the more reason to carefully read the instructions and take your time!

You might discover an important alternative voicing from the other tubes that add even greater value to you.  Yet, large numbers of you will find that most of your work will be handled by the 6072a tube, (as many professionals have discovered also). The important thing is that you have the options and that’s because... “Hey, We’re Avant Electronics And We Hear You !”

 

(1)  Hold the microphone with the Grille pointed towards your body and unscrew the bottom chrome base piece from the microphone.  Place base piece in microphone box.   (See Figure  1)

 

(2)  Gently slide the cabernet red body cover off the microphone.  Place body cover in microphone box.        (See Figure 2)

(3)  Hold microphone by the Grille Assembly and with the other hand, gently pull white tube spacer cone assembly down approx. 4mm (or 3/16”)  to disengage alignment pins.  Turn spacer slightly to clear transformer leads  (See Figure 3)

 

(4)  Push tube spacer cone assembly and tube away from microphone body, pivoting at the tube base socket.  Only pivot as much as needed to remove spacer cone assembly. Set spacer assembly aside.  (See Figure 4)

Note: There is a spring between the white plastic spacer cone and the red insulating rubber.               Do not lose this spring. (Figure 5)

(5)  Now firmly grip tube base socket and rubber insulator with index finger and thumb, supporting the rest of the microphone in the remainder of your hand.  Take care to not damage wiring and components on the circuit boards. (See figure 6)

(6)  With your other hand, gently rock the tube back and forth while pulling the tube out of the socket.  The tube may be seated firmly, so use adequate pressure to remove.  Do not allow socket to drastically move, as damage to the wiring underneath may occur. (See Figure 6)

(7)  Place removed tube in a safe place and replace with one of the extra tubes supplied (ECC81, ECC83).  To seat new tube, hold white ceramic base socket and rubber insulator again as described in Step 5, and set new tube into socket.  Take note of the tube pin alignment.  Failure to do so will result in damage to tube.  (See figure 7)

(8)  Once the tube pins are aligned with the socket, firmly push tube into the socket while using a slight rocking motion.  Firmly hold base to prevent movement. Continue this action until the tube is fully seated.     ( See Figure 8)

(9)  Push the tube from the top, pivoting at the base in order to place spacer assembly back on.         (Figure 10)

(10)  Gently push tube and spacer assembly back into place.  The alignment pins must be inserted into the 2 provided holes in the metal transformer housing for the tube to be properly supported.  (Figure 10)

(11)  Slide the cabernet body back on to the microphone with the Avantone logo closest to the Grille and centered on the same side as the pad and roll-off switches.  Gently align the notches in the body with the switches by very slightly rotating the body back and forth. (See Figure 11) The body will be fully seated when the lip is right next to the switches.

(12)  Screw the base back on.  Do not over-tighten.