Carr Mercury 2009

No Sales Tax For Customers Outside Of California.

The original Carr Mercury uses a single power tube and can be fitted with a wide variety (KT66, 6L6, 5881, EL34,...).  Changing tubes does require re-biasing.

The lowest boost setting (Boost 1) delivers fantastic cleans and even moderate overdrive tones. The Boost 1 setting has a more dynamic feel with less compression, and the Treble and Bass controls are active in the circuit.

The Treble and Bass controls are out of circuit in boost 2 & 3 positions, but the inherent amp overdrive voice in Boost 2 & 3 sounds great without needing the Treble & Bass tone controls in the circuit. One could certainly run an EQ pedal in front of amp for fine tuning tones when using Boost 2 & 3.

A Cut switch rolls off the high frequencies for a more mellow tone when the switch baton is down. This works especially well when Boost positions 2 and 3 are in use.

This example is clean and original and it works perfectly.

Bias adjustment:

To adjust the bias you will need a multimeter to measure DC voltage. These are readily
available for as little as $10 from an electronics supply store. Looking at the amp from the back, you will find two test points on the bottom of the chassis to the left of the power tube.

Insert the red meter probe into the red test point and the black probe into the black test point.

Set the meter to read DC millivolts or DC volts. Turn the amp on in standby mode. After a minute, switch the amp out of standby into the play mode, and allow it to warm up for about 5 minutes. When the amp is in the play mode, the multimeter will display a voltage—usually near 45 millivolts (0.045 volts). As the amp warms up the voltage may drop a little. Once the amp is warmed up, you can begin to make adjustments. On the back of the chassis there is a raised pan with the shaft of a potentiometer sticking out (see Chassis Diagram). This is the bias adjustment control. Turn it one way to increase the voltage, turn it the other way to decrease the voltage. Adjust the bias control until the meter reads 45 millivolts (0.045 volts).

Unplug the meter probes from the test points and your Mercury is ready to play.

We recommend biasing EL-34s at the factory bias point of 45 milliamps. We recommend
biasing all other compatible tube types at 52 milliamps. You may wish to experiment with setting the bias a little higher or lower. Lower bias current will give a leaner, clearer tone, and higher settings will give a thicker tone. We suggest staying within the range of 40 - 52 milliamps.

• Case/Cover?: No
• Color: Brown Leatherette, Cream Tolex
• Dimensions: W21" x H17" x D10"
• Weight: 40 lbs
• Watts: 8 Watts
• Date: 5-15-09
• Where is Date Noted?: Chassis
• Speaker 1 Brand: Eminence Patriot 
• Speaker 1 Size: 12"
• Speaker Code: See Pics
• Speaker 1 Cone: Original
• Power Transformer Brand/Codes: See Pics
• Choke Transformer Brand/Codes: See Pics
• Output Transformer Brand/Codes: See Pics
• Reverb Transformer Brand/Codes: See Pics
• Extension Speaker Out? No
  
• Effects Loop? No
• Reverb or other effects?: Reverb
• Power Tubes: 6L6
• Power Tube Brand: Sylvania
• Preamp Tubes: 12AX7, 12AT7, ECC83
• Preamp Tube Brand: GT, EHX, JJ
• Filter Caps: Original
• Pedal: No
• Pots/Codes: Original
• Tolex/Tweed: Original
• Grille: Original
• Knobs: Original
• Handle: Original
• Power Cord: Included
• Notes: 

Shipping policy:

When you purchase this item you are hereby agreeing to this shipping policy. We remove tubes from amps that could be damaged in shipping.  We remove the chassis from some amps so that the large transformers don't damage a chassis or cabinet.  We remove heavy speakers from some amps so they don't damage baffles.  These cases result in multiple box shipments, and they require the buyer to do some assembly on delivery.  We do this because we have experienced shipping issues in the past, and this is our prevention measure.  Vintage amps are sold as-is because they can need service intermittently.  Everything is tested here in our shop on the way into our inventory, and again before shipping.  We will cover shipping damage, but we cannot be responsible for the failure of vintage components in 20-to-50-plus year old amps. Shipments will require signature on delivery, no exceptions.  If there is damage, the buyer must retain all packing materials intact and picture them immediately and send them to sales@maharsvintageguitars.com.  Less than 1% of our shipments are damaged in transit, and we are committed to making sure your item arrives safely, but we are taking these additional measures to make sure you are happy with your purchase.