1st, I apologize for my ignorance, while I've been involved with audio gear most of my old life and often attempt my own repairs and recaps with surprisingly good success, I am about as ignorant as they come with especially the terminology.
Now the question - I pulled a toroidal transformer rated at 310VA from a Xantech DR5H 4 zone digital distribution system and while it's a good looking, "weighty" transformer the primary is 0 - 115v - 115v and it only has one secondary which is rated at 20v 15.5A
Since it just has the one secondary, in my ignorance I'm guessing this wouldn't work for an amp build so I was wondering if there were any diy projects that this would make a nice transformer for or am I just looking at a bunch of copper.
I'm needing to get a bunch of stuff cleared out so am just wondering if I'll ever have a use for this or not so am basically wondering what diy projects are out there that only require a t.transformer with only the one 20v 15.5a secondary>
Thanks for any info given
Now the question - I pulled a toroidal transformer rated at 310VA from a Xantech DR5H 4 zone digital distribution system and while it's a good looking, "weighty" transformer the primary is 0 - 115v - 115v and it only has one secondary which is rated at 20v 15.5A
Since it just has the one secondary, in my ignorance I'm guessing this wouldn't work for an amp build so I was wondering if there were any diy projects that this would make a nice transformer for or am I just looking at a bunch of copper.
I'm needing to get a bunch of stuff cleared out so am just wondering if I'll ever have a use for this or not so am basically wondering what diy projects are out there that only require a t.transformer with only the one 20v 15.5a secondary>
Thanks for any info given
You could use voltage doubler rectification and get a zero volt ground from the junction of the caps. Beware that you'll need big caps as the ripple will be at 60Hz.
Alternatively with a couple of extra caps you could build a full wave voltage doubler similar to this:
Disregard the voltages, the 10R and 0.1uF.
Voltage regulation of voltage multiplier rectification circuits is poorer than standard rectification but suits some circumstances.
Alternatively with a couple of extra caps you could build a full wave voltage doubler similar to this:
Disregard the voltages, the 10R and 0.1uF.
Voltage regulation of voltage multiplier rectification circuits is poorer than standard rectification but suits some circumstances.
It´s 2019 
There´s a ton of single supply BTL modern amplifiers, both Class AB and ClassD, search a little for one which is happy with +28V DC supply.
You can approach 100W RMS per channel into 4 ohm loads, certainly >70W RMS, I guess that supply will be quite stiff.
EDIT:for example search for an amplifier using 2 of these, each one bridged.
TPA3221 100W Stereo/200W Mono Class-D Amplifiers - Texas Instruments | Mouser
Or 2 separate mono bridged boards.
Happy with up to 30V DC single supply.
There´s a ton of single supply BTL modern amplifiers, both Class AB and ClassD, search a little for one which is happy with +28V DC supply.
You can approach 100W RMS per channel into 4 ohm loads, certainly >70W RMS, I guess that supply will be quite stiff.
EDIT:for example search for an amplifier using 2 of these, each one bridged.
TPA3221 100W Stereo/200W Mono Class-D Amplifiers - Texas Instruments | Mouser
Or 2 separate mono bridged boards.
Happy with up to 30V DC single supply.
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A collection of vintage, single supply, low to medium power amplifiers for Daniel
I wasted over a year trying to make an IC amp LM1875 work with single supply. In the end both channels motorboated at 1/2 hz. I think layout was at fault, I don't etch PCB with hazwaste taking $450 a drum to get rid of. The e-bay boards for that IC are apparently all split supply.
Board that acually worked for me point to point no ebay PCB's was the Apex AX6. link is in post 7 above thread. Listened to a couple of LP's on it this afternoon. There is a 25 w version for a lower supply voltage near the end of the pages. I don't even have the output transistor on the board, I fly wires over to them on a separate heat sink. No oscillation, but don't run inputs and output wires closely parallel BTW.
Class A is so 9v transistor radio with a 1" speaker. My Ax6 will go 70 w with 6 transistors/channel, I drive 15" woofer & 2" horn.
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