AKSA 55 lowering gain

andrewbee · « **on:** 30 Jun 2005, 03:20 am »

Hello Hugh,
Its been awhile and I see you are still busy

I need to lower the gain on my 55 to its lowest recommended setting but I cannot find my schematic. Would you please let me know which resistor it is, as in R?

Thanks

Andrew Brandon

AKSA · « **Reply #1 on:** 30 Jun 2005, 04:06 am »

Hi Andrew,

Always a pleasure to see you back!! How's Cayman?

On your pcb, it should be R8, which is 2K2. You can increase it to 3K, which lowers gain from 38.3 (31.7dB) to 28.3 (29dB).

It is not advisable to reduce it further because gain affects the pole of the amp, and hence stability. If you wish to go lower, you can put a resistive divider on the input, which effectively would simply be a series resistor on the 'hot' input terminal. 10K would reduce gain further from 28.3 down to 23.3 (27.4dB), but you should ensure this is a quality MF resistor as, being in series with the signal, it will confer its electrical characteristics on the signal.

Hope this is helpful!

Cheers,

Hugh

rabbitz · « **Reply #2 on:** 30 Jun 2005, 12:43 pm »

You could try a Rothwell in line attenuator which gives about 10dB.

http://www.rothwellaudioproducts.co.uk/html/attenuators.html

andrewbee · « **Reply #3 on:** 30 Jun 2005, 01:35 pm »

Thanks Hugh and Rabbitz.

Hugh I guess you did not hear of our misfortune last year. We are well on the road to recovery however!

http://www.davidwolfephotography.com/Stk/Ivan/

Regards

Andrew

AKSA · « **Reply #4 on:** 30 Jun 2005, 11:02 pm »

Andrew,

That's 1 helluva hurricane. Is it your house in the pictures? I'm very sorry, I didn't realise, I knew there'd been a hurricane in the Caribbean, but thought it had only grazed Cayman.

Is the damage all repaired now? You wouldn't want this to happen more than once every ten years!

Cheers,

Hugh

andrewbee · « **Reply #5 on:** 1 Jul 2005, 01:58 am »

I'm fine but 9 months later many still have no home and hurricane season started last month.
Everyone is on pins and needles but anyway back to Aksa.

I hope I have some 3K resistors to try. I have among other things on my head a very low gain line stage. I don't care what they say, a linestage simply improves the sound for me.

Thanks

Andrew

andyr · « **Reply #6 on:** 1 Jul 2005, 02:26 am »

Quote from: andrewbee

I'm fine but 9 months later many still have no home and hurricane season started last month.
Everyone is on pins and needles but anyway back to Aksa.

I hope I have some 3K resistors to try. I have among other things on my head a very low gain line stage. I don't care what they say, a linestage simply improves the sound for me.

Thanks

Andrew

Then you know which goddamn low gain linestage to choose, don'cha!!??

Regards,

Andy