Is this transformer arrangement legal?

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Frogeye is stating the output based on converting 16Vac sinewave to the peak voltage of that same sinewave.

But, that is not the way AC to DC conversion works.
As I said and you quoted
Most of the time the output from a 16Vac transformer is not 16Vac.

Vout = Vpri/Vrating*Vsec when the load passes the rated output current.

When there is no output current, then Vout = Vpri/Vrating*Vsec*{1+regulation}
If regulation for two 80VA (with +33% removed) is 10% (reg could be >14%), then
Vout with 120Vin would be around 120/115*16*1.1 ~18.4Vac
Vpk is ~26Vpk Two 16Vac transformers with a bridge rectifier could be ~52Vdc
Subtract 1V to 1.4V from that to arrive at the DC across the smoothing capacitors and you get ±25.3Vdc to ±25.5Vdc.
Attach a load and the 16Vac to ±24Vdc shown in your post1 is actually quite close.

Simply applying sqrt(2) does not predict the DC accurately.

unwound the secondaries by hand and stopped unwinding when I got to 16 v

So it is 16V at no load. It will decrease when loaded and further drops on 2 sets of bridge rectifier. Maybe the unaltered 24 V secondary would had been better for reaching 24V DC at continuous load. Also the coverage of the toroid would had been more even, which is neccessary condition for a toroid not to emit magnetic field.

Mixing drop and regulation, loaded and unloaded voltage, measured and rated voltage, AC and DC voltages, pure sinewave and clipped sine introduces many errors.

For a correct calculation only 5 values are needed:
Unloaded secondary voltage,
Primary and secondary resistance
Primary voltage
Load current.
(+ of course diode drop, but this is an independent component.)

Without these everything is only guesstimation.
 
Okay, I must jump back in here. Sorry to have caused such confusion by Using my name instead of my "handle." My name is indeed Hal, my handle is Frogeye.

On the question of a 24 Volt supply, I will go with Nelson Pass who uses 18 Volt transformers for his 24 Volt supplies.

Hal
 
I appreciate all the help on this topic. I have all my power supply issues solved so I thought an update is in order.

The reason for the original post was that I wanted to turn the heat down in my 30 year old class A "kit" that was blowing smoke every hour of use (see my other posts in the amplifier section of diyAudio). I used a variac and adjusted the voltage on the mains such that the output transistors were running at 60 degress C instead of 85 -90.

The amp was running at 32v per rail, and tried many suggestions from others but to no avail. I still needed to get the heat down, so according to the variac method, I needed to run at 24v to reach optimal heat. I simply unwound the transformers that produced 32v originally until I reached my goal of 24v . The final windings were distributed around the donut for even spacing.

I don't know the technical details except for the results. Smooth, clear audio with lowered heat production...which was my goal.

The results are OUTSTANDING! There is PLENTY of power left. Crystal clear audio, impressive quality. Plenty loud (for an audiologst that knows better than to go loud) Temperatures run at about 55-60 degrees C instead of 90.
Again, thanks for everyone's advice.
 
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