What BIAS current is suitable for me?

[wuffwaff]

Hi,

I think 10A of bias is a bit much for 17V and for your speakers. You will have 340 watts dissipation per channel and must use at least 12 Fets/channel. I you want thze dissipation it would probably be better to up the voltage a bit.

William

 

[lscangus]

but from Mr Pass, higher current means better quality. and i think 60W will be enough for my proac

 

[Nelson Pass]

Realistically, Alephs don't meet my needs until the rails get up
around 20 volts or more. For that power and current sources
at 50%, you are looking at a minimum of 4 amps bias total, which
comes out at 160 watts or so. If you are using 4 devices per
channel, the highest you might want to run it is maybe 5 amps,
which is 50 watts per device.

 

[lscangus]

so, will it be better if i use 21.7V and 8A?

Angus

 

[wuffwaff]

or 6A........

William

 

[lscangus]

or 6A........

William

but why 6A is better than 8A?

 

[wuffwaff]

Hi,

just trying to save you some money for heatsinks/ transformers/ fets etc.

You speakers are not really critical so 6A of bias should be fine.

If cost is no problem you can go for 8A bias but you have to consider that this will enlarge the problems you will encounter.

William

 

[lscangus]

Hi,

just trying to save you some money for heatsinks/ transformers/ fets etc.

You speakers are not really critical so 6A of bias should be fine.

If cost is no problem you can go for 8A bias but you have to consider that this will enlarge the problems you will encounter.

William

i am using two 0.26C/W heatsinks to mount total of 16 fets. with a 12X12 CM fan to increase air flow.. so i think it will be alright.

So.. finally.. 17V or 21.7V for the rail? as if i go for 17V, i can have higher current. but will it be powerful enough for my speakers?

 

[wuffwaff]

Then go for the higher voltage.

 

[lscangus]

Then go for the higher voltage.

thanks very much! i will have a thought and i will post the picture of my ampa dn the working process later.