I couldn't figure out why my DC-10 had MUCH better Reverb than my DC-5A. The 10 is a really early model, serial #99.
I always assumed that they had the same circuit. In fact, I had glanced over the circuits many times and never seen any significant differences. There was an extra capacitor and that was all.
I even measured the voltages in my DC-5A today to compare them to the drawings. They were really close.
Then, the candle above my head slowly started to ignite! :lol:
I looked at the drawings again, side by side and I found the differences between version A & B!
Here is a really simple mod that will make your DC-5A's Reverb significantly better:
Remove the chassis from the amp.
Make sure to discharge the capacitors.
Face the knobs of the chassis toward you.
Find the .002 capacitor that is attached to Pin 1 of V5. It will be slightly to the back of the amp and to the left of the tube.
Remove it.
Unsolder Pin 1 of V5. Be careful, the Blue wire from the Reverb Transformer is pressed up against the Pin and soldered there. Make sure you get all of the solder out of the hole, or as much as you can.
You will see 2 unused solder tabs (they are full of solder) just to the front of the amp and to the left of the tube. Measure these to ground. You should have around 1 ohm or so.
Clean the one out that is closest to the tube.
Bend the ends of the capacitor that you removed so that they will fit between the hole you just cleaned out and the hole where Pin 1 of V5 is.
Solder this capacitor in place.
Next,
Locate the Reverb Return Jack. It is an RCA Jack located at the bottom of the chassis. It will be the one closest to the front of the amp. It is also the one that the Black cable connects to.
You will see a shielded wire leading from Pin 7 of V5 to the Positive connection (Center Connection, not the Shield) of this RCA Jack. You will also see a Blue wire leading from this same connection to the Tip of your Reverb/EQ footswitch jack.
Solder a .001 microfarad capacitor from this connection to Ground.
That is it. You will have about twice the Reverb that you had before.
I always assumed that they had the same circuit. In fact, I had glanced over the circuits many times and never seen any significant differences. There was an extra capacitor and that was all.
I even measured the voltages in my DC-5A today to compare them to the drawings. They were really close.
Then, the candle above my head slowly started to ignite! :lol:
I looked at the drawings again, side by side and I found the differences between version A & B!
Here is a really simple mod that will make your DC-5A's Reverb significantly better:
Remove the chassis from the amp.
Make sure to discharge the capacitors.
Face the knobs of the chassis toward you.
Find the .002 capacitor that is attached to Pin 1 of V5. It will be slightly to the back of the amp and to the left of the tube.
Remove it.
Unsolder Pin 1 of V5. Be careful, the Blue wire from the Reverb Transformer is pressed up against the Pin and soldered there. Make sure you get all of the solder out of the hole, or as much as you can.
You will see 2 unused solder tabs (they are full of solder) just to the front of the amp and to the left of the tube. Measure these to ground. You should have around 1 ohm or so.
Clean the one out that is closest to the tube.
Bend the ends of the capacitor that you removed so that they will fit between the hole you just cleaned out and the hole where Pin 1 of V5 is.
Solder this capacitor in place.
Next,
Locate the Reverb Return Jack. It is an RCA Jack located at the bottom of the chassis. It will be the one closest to the front of the amp. It is also the one that the Black cable connects to.
You will see a shielded wire leading from Pin 7 of V5 to the Positive connection (Center Connection, not the Shield) of this RCA Jack. You will also see a Blue wire leading from this same connection to the Tip of your Reverb/EQ footswitch jack.
Solder a .001 microfarad capacitor from this connection to Ground.
That is it. You will have about twice the Reverb that you had before.
