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Not quite, let us step test it......







Applying a 15% current step to the Finals at 4.1 seconds. we can simulate your supply. It is wasteful as a design. Unfocussed. It has a dynamic Z of 296 Ohms, and it settles in ( yawn ) 385 mS.

John Swenson who did measurements of recovery times and posted it previously on this Forum sez, "50 mS. or less is nice".

My suggestion, the second simulation, with the same 15% current step to the Finals, settles in about 50 mS., over seven times faster, and has a dynamic Z of 229 Ohms, over 20% lower, using tube rectifiers that are very common and inexpensive compared to two 5AR4s.

Specific off-the-shelf industrial parts of my suggested supply is as follows : One Hammond 372KX power trannie, 600 VCT at 575 mA., 23 Ohm HV secondary, Shared L1, one Signal Transformer Co. CL-1-2, 72 mHY at 1.5 A at 1.4 Ohms, 20 uF L1, .

From the shared L1/C1, you go to a "Y" to each channel, with a L2 and C2 to each P-P output section. L2 becomes the new Edcor 2 Hy 200 mA. 21 Ohm device, and C2 is 50 uF to feed the finals.

For the front end, one can use either a third choke or a R-Dropper to get adequate LOW ripple. Speaking of ripple, my above-suggested "fast dynamic recovery" supply has about 1 VAC of ripple, and in a P-P amp, you will NOT detect that feeding the finals. My supply comes in at 323 VDC assuming a 120 VAC line, if your home's line 122 VAC, about 2% more, you will have your 330 VDC target to the finals.

Your supply uses two 40 Ohm DCR chokes in series, (80 Ohms total) and that DCR (40 Ohms in a choke to the Finals) KILLS the amp dynamically. Both of my suggested chokes in series total only 23 Ohms, and that will do the job nicely. Your 220 uF caps to the Finals will deliver energy out-of-time, and hog current from the Finals when the music instantaneously needs it, as per JLH's concise posts on this in about 2008 to 2010.


My suggestion is off the top of my head. It should boggie woogie with the BIG boys very very well Lektrik.

Jeff Medwin



Edits: 07/10/12 07/10/12 07/10/12

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  • Not quite, let us step test it...... - drlowmu 18:58:13 07/10/12 (1)

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