Could Vinnie or someone briefly describe the technological differences between the amplifiers in the Teac A-L700P and Sharp SD-EX111?
I own both and the Teac’s have a Tripath chip which appears to handle amplification chores as it’s heat sinked, yet puts out very little heat regardless of volume level.
OTOH, the Sharp appears to have 4 small heat-sinked output transistors which generate a moderate amount of heat.
Can anyone describe the major differences between the 2 topologies?
Thanks!
tw
Hi TW,
The Teac uses a Tripath chipset, which is called Class-T amplification. This uses Tripath's proprietory high frequency switching algorithm (called DPP, or Digital Power Processing) to modulate the input signal that enters the chip. It is 'sort of' similar to Class D, but more complex.
The Sharp's amplfication topology consists of Sharp's 7th order delta-sigma modulation chip, followed by a switching power amplifer chip. This technique is very similar to SACD's (DSD)), and the switching frequency is 5.64MHz (128 x 44.1kHz...no coincidence there

). There is another Sharp using that uses a lower freq of 2.82MHz (64 x 44.1kHz).
You are feeling more heat out of the Sharp because it uses all-linear power supplies, which are less efficient (generates more heat) but much cleaner. The Teac uses a high freq. switching power supply that is more efficient (geneates less heat), but generates more high freq hash (noise).
>>OTOH, the Sharp appears to have 4 small heat-sinked output transistors which generate a moderate amount of heat.
No, these are the linear regulators...part of the power supply, not the amplifier chips. Actually, the amplifer stage, as well as the cdp's dac stage, are individually enclosed in metal boxes (very nice!

), and have all separatle regulated supplies. Remember, the Sharp did sell for $499 in 2003, so you'd expect this degree of higher quality for this price...if you were a *cough* sucker *cough* back then.
Hope this helps,