I recently did some SPICE simulations of the Aleph 2 and 4 circuits and found some disturbing results...........

Here is what I did: I ran a transient analysis of the amp into different resistive loads. I increased the input voltage until clipping occurred. At clipping I recorded the peak output voltage delivered by the amp into the various loads. Here are the results...........

Aleph4 (bias came out to be 2.25 amps total)

(R29=619 ohm)

81 Wrms @8 ohm (162 peak)

60 Wrms @6 ohm (121 peak)

40 Wrms @4 ohm (81 peak)

20 Wrms @2 ohm (40 peak)

(R29=523)

100 Wrms @8 ohm (200 peak)

92 Wrms @6 ohm (184 peak)

62 Wrms @4 ohm (123 peak)

30 Wrms @2 ohm (60 peak)

Aleph2 (bias came out to be 2.5 amps total)

100 Wrms @8 ohm (200 peak)

133 Wrms @6 ohm (266 peak)

140 Wrms @4 ohm (280 peak)

71 Wrms @2 ohm (142 peak)

So what does this mean???

It appears that according to simulation the Aleph4

is not exactly capable of it's ratings. Of course, simulations can be wrong (those damn computers!)

I have found that only slight changes to the bias current can affect the power output a great deal. Maybe the simulation is just off slightly, I'm not sure (I would think DC bias currents would be pretty accurate).

Has anyone tested their Aleph constructions or commercial offerings for maximum power output??

I would be interested to know if they really do perform as outlined in the user manuals.

If no one knows I guess I will have to wait until I finish mine.

I will run some tests (when I get the thing built of course) and post when I get some experimental measurements to back my simulations.

Perhaps Mr. Pass can help us with this one.

I am very interested in this.

Happy Listening

Jake