Everything in these amps was done with a purpose for SQ and reliability. The amps share NOTHING between the two channels, they source their own ground from one common point in the power supply and are not combined anywhere in the signal chain. Every signal path in the amp is shrouded by a ground trace on each side of the signal line to create a 360 degree noise shield around the signal, the board is 3 OZ copper, the big big class D amps are proud of saying they use 2 OZ copper. We use 3 OZ to minimize any high current losses, increase efficiency, and to reduce heat build up in the board.
We use twin Burr Brown op-amps and neither channel is shared between the two. Every electrolytic cap in the signal path and some in the power supply use WIMA by-pass caps as a SQ improvement. Tru Technology gets several hindred dollars jsut to add these caps as one of their stage upgrade to the amps.
Even the gain pot is a 10% part where the standard for the industry is a 20% gain pot. The gain pot is the nearest point that the two signal paths come to each other.
These amps can be ordered with a DIP header and a DIP pack to set the voltage input exactly to the headunit (2,4,5 7,8 volts in) instead of using a gain control. There will be a plug in crossover card availiable and factory installed when ordering for the people that want a crossover. For those who don't the siganl path will be un-effected by the crossover since it will not be plugged in. The crossover card will also utilize a gain control or DIP packs to exactly set the crossover points and stop any chance of signal difference between the two channels. Ther is plenty more I can go over about these amps. We will post a pic of the old heat sink in a little bit and I will go over those improvements we added to the new heat sink. These amps can't be touched by anything we have done in the past and will outperform anything on the market that is true SQ.
The power filtering is handled in three stages to decrease noise to a bare minimum, the power is filtered directly at the bridge rectifiers, then again when leaving the power supply in the center of the board, and again directly at the output devices to keep the power to them as squeaky clean as possible and to storing energy directly at the output devices. All caps are high grade audio caps, that are extremely low ESR and high temp caps. 6 different protection systems protect the amp, and are non-interactiive with the signal path. This is just a few of the advantages to this amp.
Power supply efficiency is in the plus 80 percent range and over all efficiency is in the low to mid 70 percent range. The LP2150 will make rated power of 150 x 2 with 30 amps of current. An example of the 2.2HV versus the first prototype of the LP2150, the 2.2HV had an internal voltage of 97 volts and the LP2150 had an internal voltage of 84 volts, yet the power output was almost identical except at low frequency and the 2150 beat the 2.2HV, the final version of the 2150 makes tons more power than a 2.2HV and also sounds tons better, and the 2.2HV was known as one of the great SQ amps.
We also use the highest grade of audio devices currently offered by On semi (Motorola) these devices only run at 30 percent of their capability, they are also the largest plastic cased audio devices on the market (they have the EXACT electrical specs as the meatl cased TO-3 transistor, these are TO-3P devices, they are jsut derated by 25 watts of heat dissaparion from the TO-3 metal cased parts). we used these to dissapate heat effectively and quickly into the heat sink. The power supply only runs at around 27 percent of its capability at rated power. This terminates in well over 3 dB of headroom, and the damping factor is rated at the speaker terminals at 20 Hzs at greater than 375, not taken from an point on the circuit board to get a higher rating or at a higher frequency to make the figure bigger.