Apogee Scintilla Power

westerlm OP
I have recently picked up a Plinius SA250 MkIV that is being refreshed and turned into a Reference. Has proven to operate steady at 1ohm load handling scintilla dips down to .85ohms with high power and current.

This "could" be the one for you, Plinius usually use mosfet in their output which sag not increase into 2ohms
But it "seems" for this SA250 they may have used bi-polar (bjt) in this model, but! not complimentary npn/pnp but just npn for top and bottom rails.
Maybe they meant N channel only top and bottom (not npn) and it is Mosfet, then that would explain this comment when tested into 2ohms " the amplifier is clearly less comfortable with the 2 ohm load" which means not so good with your Apogee’s 0.9ohm loading


Still it can give a good wattage increase for every halving of impedance
320W into 8 ohms
480W into 4 ohms
740W into 2 ohms (single channel driven)

Cheers George

Question
What is this "Scintilla Mod" that you mentioned that was done to your  Sunfire?
I have a Cinema Grand Signature and always wondered if it could drive some Scintillas. Not like I'd ever get that opportunity, but I digress..

As a matter of interest I have been compiling a list of amplifiers that will drive 1 ohm loads in particular the Apogee Scintilla. 

This is one speaker that I have always wanted to own but not easy as I am UK based, as they say owning a pair of Scintillas or Divas i9s an itch I would like to scratch!!

Apogee Scintilla - List of Krell Amplifiers that can drive them

Krell KSA50 (Just)

KSA100,

KMA100,

KMA200,

KRS-100

KRS-200

Krell KSA 80 (Just with protection setting adjustment)

KMA 160,

KSA200,

KMA 400

KSA150,

KSA250,

MDA 300,

MDS 500

Krell Audio Standard (KAS)

Possible KSA100s

Possible KSA200s

KSA300s

FPBs possibly

Evolution series a Possibly?

I am going to investigate the suitability of the following to drive a 1 ohm load

Krell FPB 750mcx and Krell Evolution 900

For my 700cx replacement, I may be considering

Krell KRS-200 too old? serviceable?
Krell KMA400 these run very hot so I question longevity and serviceability
Krell MDA500 again these run hot and question longevity and serviceability

I am most li8kely to consider the last two as they are the most recent and on performance grounds provided they can drive a 1 ohm load.

Krell FPB750mcx or Krell Evolution 900

I am most likely to consider the last two amplifiers mentioned above and below, as they are the most recent, and probably superior in audio performance.

Consideration will also be given to them provided they can drive the 1 ohm load of the Apogee Scintilla.

I have specified this parameter, just in case I decide to scratch the itch I have had since the late 1980s (teenage!!) to try out a pair of these loudspeakers in my main system.

Krell FPB750mcx or Krell Evolution 900

Simon