Bryston 4B SST clone

[amplidude]

I could get you this one with gold top, 3.5kw dual 42 volt weight around 30 kilos

 

[chalky]

Nice stash of transformers there amplitude

 

[trampo]

Thanks for the replies.

So I think I got this a bit wrong, the 250va was per winding, so that's probably it bit overkill at 1000va total.
Do I spec this as 500VA total with 4 windings at 45v?

 

[amplidude]

How are you going to run it? Will you parallel the two sets of secondary, doubling the watts ?Meaining one toroid pr channel? Or use the one toroid mentioned for both channels?

 

[trampo]

1 toroid for both channels using 2 windings for left channel and 2 windings for the right.

 

[amplidude]

Okay, like that, listen to chalky and get one with at least 500w rating then, or best option sound wise running everything dual, two toroids, better channel seperation

 

[josejuancano]

Bryston input

Hi Friends, I purchase this pcb's for made clone Bryston B28 SSt2 and supplier send me schematic, only arrived pcb filter, but in pcb input I don't understand why it doesn't carry potentiometer, how do you turn the volume up and down?you need another pcb? a friend told me that I could adapt a 1ooK alps potentiometer, could you adapt that potentiometer? and where to coect it correctly, my design is with 2 pcb's stereo, powered by two toroid transformers of 1000VA each 80-0-80V, I bought 12 capacitors of 10,000 Uf 125V, is there any improvement in the components? still because of the pandemic I have not received several components, only the filter pcb that I have already placed zener, relay, resistors, and regulators 7812 and 7805 I attached photos, if someone has assembled it and changed components to better I would appreciate the help, since the documents that the Chinese has sent are not very good and create me doubts, is a great project for me, thank you all, greetings

 

[amplidude]

That toroid is gonna fry your amp. That's +/÷ 112 volts, 90 volts is it's limit.
Is it like the one on picture?

 

[amplidude]

You would need something like a 50 to 60 volt toroidal transformer instead.
As to potentiometer, the bryston 28b is a power amp with no potentiometer, wire something like a 10k pot at input.

 

[josejuancano]

That toroid is gonna fry your amp. That's +/÷ 112 volts, 90 volts is it's limit.
Is it like the one on picture?

Is it the only transformer I've been able to get, how could I lower the voltage? is 80-0-80V 6.25A each

is for B28 SSt2 is other pcb in other post is schematic, thanks friend

 

[josejuancano]

You would need something like a 50 to 60 volt toroidal transformer instead.
As to potentiometer, the bryston 28b is a power amp with no potentiometer, wire something like a 10k pot at input.

I bought the 100K alps potentiometer on ebay with mini pcb wouldn't that be worth it?

 

[amplidude]

Lowering the toroid voltage is not easy, it would require you removing some secondary windings, not an easy job, the input board is fed together with the output board and dosent need separate psu.
If the toroid is new and unused, can't you return it ? , I wouldn't even try using it.

 

[amplidude]

When the ac output voltage of toroid is passed through rectifier and caps its increasing in voltage, if toroid is 80 volt ac, times factor 1.4 112 volt dc

 

[amplidude]

Potentiometer would work but is it correct values? I'm not sure, its value should be a product of source impedance and input impedance squared and doubled, I think that's the way to do it.
But you biggest issue now is power supply.

 

[josejuancano]

Potentiometer would work but is it correct values? I'm not sure, its value should be a product of source impedance and input impedance squared and doubled, I think that's the way to do it.
But you biggest issue now is power supply.

if friend, the non-load transformer gives 86V 1.6mm copper 172 turns secondary

 

[josejuancano]

When the ac output voltage of toroid is passed through rectifier and caps its increasing in voltage, if toroid is 80 volt ac, times factor 1.4 112 volt dc

thank you friend I'll try to remove copper from the secondary up to 66v x 1.4 x 92v without charge

 

[amplidude]

I didn't recommend you do that, its your choice

 

[amplidude]

Running any equipment to it's limit, is not a good recipe for success.

 

[chalky]

Seconded amplitude. I wouldn't use a supply of more than +/-75Vdc with this power amp.

 

[hschier]

Hi master of Diy. Can i use 2sc5200/2sa1943 pair like power amp for the 4B?