[leusink1]

Hi Everyone,

This is the dillemma I'm having,

I would like to (passively) bi-amp the woofers with a 3B ST, and the tweeters with a 2B LP pro

They have different input sensitivities:

3b ST= 2v (for balanced input), 23db gain or 1v (unbalanced input), 29db gain
2B LP pro = 0.775V for both balanced and unbalanced input, 29db gain.

Is all that matters the gain required for full output or should both amps have the same input sensitivity (in volts) as well?

I don't want the tweeters to receive even +/- .5 db more or less than the woofers, as this would change the character of the speaker.

Can anyone help me out here?

Thanks in advance,

Albert

[James Tanner]

Hi Everyone,

This is the dillemma I'm having,

I would like to (passively) bi-amp the woofers with a 3B ST, and the tweeters with a 2B LP pro

They have different input sensitivities:

3b ST= 2v (for balanced input), 23db gain or 1v (unbalanced input), 29db gain
2B LP pro = 0.775V for both balanced and unbalanced input, 29db gain.

Is all that matters the gain required for full output or should both amps have the same input sensitivity (in volts) as well?

I don't want the tweeters to receive even +/- .5 db more or less than the woofers, as this would change the character of the speaker.

Can anyone help me out here?

Thanks in advance,

Albert

Hi Albert,

Welcome - it is the GAIN that matters.

All Bryston amplifiers have the same GAIN so they can be mixed and matched easily in passive setups like yours.

james

[leusink1]

James,

Thanks for your answer.
Just one more clarification please.

In my situation, would you suggest to use the unbalanced inputs on the 3bst, and leave the gain controls
on the 2blp pro at max, or do you suggest something else.

Also, if my calculations are correct (which I'm sure they are not, so maybe you can clarify..) I get the following gain:

3B ST (unbalanced):  1 V (50K) into 8 ohms at 120 W full output= 29.82 dB
2B LP pro (unbalanced or balanced): 0.775 V (50K) into 8 ohms at 60 W full output = 29.02 dB

Does this mean a 0.8 dB difference in output gain ?....

Thanks

[James Tanner]

James,

Thanks for your answer.
Just one more clarification please.

In my situation, would you suggest to use the unbalanced inputs on the 3bst, and leave the gain controls
on the 2blp pro at max, or do you suggest something else.

Also, if my calculations are correct (which I'm sure they are not, so maybe you can clarify..) I get the following gain:

3B ST (unbalanced):  1 V (50K) into 8 ohms at 120 W full output= 29.82 dB
2B LP pro (unbalanced or balanced): 0.775 V (50K) into 8 ohms at 60 W full output = 29.02 dB

Does this mean a 0.8 dB difference in output gain ?....

Thanks

Hi,

Input from engineering for you:


Hi James;
 
The sensitivity ratings on these amps are based on different power ratings, and actaully mean the same gain between the Unbalanced input on the 3B ST and the Balanced input on the 2B LP. 

The 2B LP would need to be modified to either give it unbalanced inputs or reduce the gain at its balanced inputs by 6dB, to match the 3B ST. This can be done very easily by the Bryston Service Office.
 
cwr