Martin Logan woofer amplification


I was discussing a possible trade in for my Martin Logan Montis speakers. The store owner was reticent, stating that the amplifier for the woofer was an OP amp. I was surprised to hear that, since the operating space is so large. I thought it was a Class D switching amp, which should work well in a non ventilated cabinet, and operating at a low frequency. Any Martin Logan experts out there?
tennisdoc40
My guess is that the reviewer of the Summit was using the word "bipolar" in a very loose sense, perhaps without fully understanding what a "bipolar amplifier" is. For that matter, I don't fully understand what it is :-), and it seems like ambiguous terminology at best.

I would expect that in general it would refer to an amplifier which uses bipolar (NPN or PNP) output transistors, as opposed to FETs. The ICEpower modules use some bipolar transistors, but not as the power transistors which drive their outputs.

But perhaps he was using the term in reference to how the two ICEpower modules are used in conjunction with each other, perhaps in some sort of a balanced configuration. Although I'm not sure that makes sense either.

Best regards,
-- Al
Martin Logan says: "MartinLogan's dedicated in-house design and engineering team created an extremely precise 24-bit Vojtko DSP engine in conjunction with a powerful 200-watt class-D amplifier to deliver a stunningly detailed low-frequency performance reaching down to 29Hz—uncommon in cabinets this compact."
A few years back, I switched amplifiers to Bel Canto Ref1000MKII's to drive my Summits. There was an incompatibility between the amps and the crossover in the Summits that Martin Logan was aware of. I called them up and the sent me out two small replacement circuit boards. I had to disassemble the cabinets and I saw the ASC200 boards with my own eyes.