[avahifi]

Ah, so many specifications, so little information. 

Two hundred watts into eight ohms pulls 5 amps of current. Specifying a lot higher power into lower load impedances is only true if speaker fuses are increased in size too, usually resulting in reduced or no protection at all to the speakers or the amplifer. How much power is 200 watts?  An experiment is to place two 100 watt light bulb sockets wired into a metal bread box.  After it has been on for an hour or so, place bare hands firmly on metal box.  While getting third degree burns to hands treated, comtemplate how well your speaker voice coils would have handled that.

Nobody talks about how fast the current can be supplied.  Also many amp current capacity specifications numbers are arrived at by taking the max current spec of an output device and multiplying by the number of devices.  This does not take into consideration that the devices have voltage/current limiting curves.  The higher the voltage across the device the lower the current rating.  Thus many of these current numbers are unrealistically inflated.

We had chosen to essentially retire from the specification race because of the lack of useful information this provides. Watts are not watts, unless you have the info to consider all the variables, not just a few of them.

Regards,

Frank Van Alstine

[bummrush]

I,m using Legacy studio monitors,they totally come alive with this amp,

[Syrah]

I'm not a techie. I'll let them explain the technicalities of this, but (to create even more confusion) tube amplifiers operate differently into low ohms. 

For years I stayed away from tubes on my ESL panels, believing what many say - that panels need stable big solid state. 

From just listening, I can't tell you how wrong that advice was.  My Dodd Audio 120s light up my panels with room to spare.  My former amp was an Innersound 300, and the Dodds do subjectively just as good a job if not better - at less than half the nominal wattage.

Peter McAlister explained the reason for this to me.  My apologies for butchering the explanation, but apparently tubes have an easier time running a high-capacitance load (which ELSs are) and solid state has an easier time with a high resistance load.

This reasoning explains why, on my Martin Logans, big solid state amps totally outperform tubes on the big 10" woofer section; yet tubes seem to outperform solid state on the panels.

All very interesting stuff.

[NewBuyer]

Yes, those figures are peak-to-peak and I would be quite surprised if the power is sustainable over a continuous period of time...

A stereo amp certainly should not need to sustain 200 amps continuously, yikes  , but 600W/channel 2-ohm stability, and 200 amps peak-to-peak, is nothing to take lightly(?) I'm not one of the experts around here, but I think that having the ability to deliver instantaneously in this manner, ensures appropriate dynamic range and no clipping behavior or distortion during musical transients/peaks (at least according to Musical Fidelity).

Specs aside though, listening is the only truly significant test for me in this subject. I hope more people will get a chance to audition this amp. Even at low volume levels, the Musical Fidelity A5cr amplifier has an ability to resolve the delicate highs and the deepest lows in the most convincing and pleasing manner that I've ever heard, with every speaker set I've paired with it. The source-switching/dual line outputs/dual speaker outputs is also very nice for me. The choke-regulated power supply probably doesn't hurt either. I only wish it had balanced inputs - but I use a Jensen transformer product for that.

[denjo]

Newbuyer

A stereo amp certainly should not need to sustain 200 amps continuously, yikes   

You would need that ability with certain types of low impedance magnetic speakers in general (Dynaudio, Thiels, for example) and electrostatic speakers in particular!  Much would depend on the music as well. One good way of testing whether an amplifier is high current is to see if it would satisfactorily drive electrostatic speakers to satisfying levels.

[avahifi]

We had one of our big amps driving four awesome restored KLH9 electrostats at the recent Detroit Audiokarma show.  The giant full range electrostats were connected in parallel, the amp was driving two per channel.

Results, no sweat, the amp did the job for two long days, producing a lovely wall of sound.

I guess that satisfied us that our amps could drive difficult loads.

Regard,

Frank Van Alstine