All,
As promised, below are some more details about the Clari-T-Amp. I still need to write a few paragraphs about the sound, but I also want others to post their findings when these are sold. I should also work on a Q & A section as well.
As you will read, there is more to the Clari-T-Amp than meets the eye
(see
http://photos.yahoo.com/vinnie822 for some preliminary photos).
Here goes:
PRODUCT DESCRIPTIONThe Clari-T-Amp is a battery powered Class-T high-fidelity stereo amplifier. Inside its portable-sized (4 x 6 x 2.5 inch) sleek black-anodized aluminum enclosure houses a highly modified version of the Sonic Impact T-Amp’s circuit board, along with a 12V Sealed Lead Acid (SLA) battery, and a “shunt-mode” passive volume control.
DESIGN GOALThe main design goal of the Clari-T-Amp is to significantly improve upon both the sound and build quality of the Sonic Impact T-Amp, while maintaining its small size and simplicity.
COMPONENTSAMPLIFIER BOARDThe small surface-mount technology (SMT) amplifier board in the Clari-T-Amp is a highly modified version of the one used in the Sonic Impact T-Amp.
Modifications include:a) 12V supply wire is soldered directly to the input power pins of the TA2024 chip with a short run of 18 gauge solid-copper wire. This provides the most direct power path to the chip, reducing noise as well as the series resistance and inductance contained in the small power traces that travel from the DC jack and across the board to the TA2024.
b) Power supply decoupling capacitance is increased by 10X the stock value using two low ESR 16V, 1,500uF Panasonic FC capacitors bypassed with 0.1uF surface mount caps. The positive leads of the capacitors are soldered directly onto the exposed power trace (surface-mount style) that attaches to the input power pins of the TA2024. Bass performance is substantially increased, while power supply droop is decreased.
c) Surface mount gain resistors are changed to reduce the amplifier gain to approximately the ideal value of 12V/V (per the TA2024 datasheet). This reduces noise and distortion and allows for a more usable range of the volume control.
d) Input signal path is substantially shortened and cleaned up. Here’s how:
In the stock board, the input signal travels a long path from the stereo mini-jack to signal traces that travel over the length of the board, adding L, R, and C elements and noise to the input signal. It then passes through a connector and cable into another connector on the stock potentiometer board. Finally, it travels back out the connector on the potentiometer board and into the other end of the connector on the amplifier board. Needless to say, this long path is not “short and sweet.”
The Clari-T-Amp sends the input signal directly to the input terminals of the shunt-mode pot, and then it is sent out directly to the amp board. Excess trace length and cheap cable connectors are completely bypass. Signal wire is upgraded to 24ga solid copper wire.
e) Surface mount input load resistors to GND are removed
f) Surface mount series input inductors are removed and replaced with solid copper
g) Four Schottky diodes are soldered to the speaker output pins. These are used to minimize undershoot of the outputs with respect to the power GND during switching transitions of the TA2024’s output FETs.
h) Speaker wire to binding posts is beefed up to 18 gauge solid copper wire
i) Stock LED on board is removed
BUILT-IN VOLUME CONTROLThe Clari-T-Amp contains a built in passive “shunt-mode” potentiometer to control the volume. In this configuration, only one resistor is actually in the signal path. The potentiometer is simply used to shunt a portion of the signal to ground (which varies with knob position).
BATTERY POWEREDThe enclosure houses a 12V, 1.3Ah SLA (Sealed Lead-Acid) battery. This battery has the advantages of a noise-free high-current output, small size (portability), and simplicity over an ac/dc power supply. It also costs much less than a high quality linear-regulated ac/dc power supply found in most amplifiers. You no longer will even need to be concerned with power conditioners and power cords.
BATTERY CHARGERThe Clari-T-Amp comes with an Automatic Charger for the 12V SLA battery. When the charger is plugged into the Clari-T-Amp jack, a red LED on the charger indicates that charging is taking place. At the end of the charge cycle, a green LED on the charger indicates the battery is fully charged and is being maintained.
REAR PLATE INPUTS AND OUTPUTSOne L/R pair of high quality, ruggedly built and gold plated RCA jacks (to withstand abuse and oxidation) for the low-level input.
One L/R pair of speaker binding posts that will accommodate either a standard dual banana plug, up to 16 gauge bare wire, or high current spade connectors stacked up to 5mm high.
One ON/CHARGE mini toggle switch (when the battery charger plug is not connected, it is essentially an ON/OFF switch).
One DC jack for the SLA battery charger plug.
FRONT PANELOne center-mounted anodized aluminum volume knob
One blue LED that is illuminated when the amp is switched ON.
ENCLOSURE The enclosure is a solidly built, black-anodized extruded aluminum enclosure measuring only 4” wide x 6” deep x 2.5” tall. It was chosen for its small size, solid construction, smooth looking appearance, and noise shielding properties.
Thank your for your interest (and patience in reading this
)
As always, feel free to email me with any questions. I will try to respond promptly during the evenings...
-Vinnie
