1 source to 2 amps

[rfarn]

What is the PROPER way to attach 1 preamp to 2 or more amps? The preamp only has 1 output. Currently they are just split with a Y cord.

[AndrewT]

good enough.

But, do check that both power amps have DC blocking caps on their inputs.

[rfarn]

Andrew,

How do I tell if they do have DC blocking caps? Will this work for more than 2? At what point would I have to worry about signal loss, resistance, etc?



Bob

[AndrewT]

check the spec or open it up to see if the blocking cap (one on each channel) is fitted.

Let's suppose your pre has an output impedance of 500ohms and that is is capable of driving a 10k load.

Now your power amps have an input impedance of, say, 22kohms.
Two in parallel = 11kohms and is above the minimum load impedance for the pre.
Three in parallel would be 7k3, below specified minimum load impedance and not suitable.

Read your specs and find out what each are.

[nigelwright7557]

Originally posted by AndrewT
check the spec or open it up to see if the blocking cap (one on each channel) is fitted.

Let's suppose your pre has an output impedance of 500ohms and that is is capable of driving a 10k load.

Now your power amps have an input impedance of, say, 22kohms.
Two in parallel = 11kohms and is above the minimum load impedance for the pre.
Three in parallel would be 7k3, below specified minimum load impedance and not suitable.

Read your specs and find out what each are.

Much more than 2 and you will need a splitter/buffer.

[Iván Francisco]

Take a look to this

[whoandcar]

Why a gain of 10?

[nigelwright7557]

Originally posted by whoandcar
Why a gain of 10?

Its also got a 10 second power up on the 100uF..........

I dont know why the 100uF is connected to half VCC.
It only needs none inverting input connected to half VCC

[AndrewT]

forget post 6.

check your specifications first.