Trying to add a Main-in/Pre-out to a Sony amplifier:

(There were useful replies, in an earlier thread, from K. Robinson,
Jerry G. and NSM about this topic)

The amplifier model: Sony TA-F590ES, with motorized volume control.

The amplifier has an "adaptor loop" with bridged IN & OUT cinch(RCA)
connectors before the volume control.

The aim is to insert a 2-way active crossover, and resend the
high-range output to the Sony. The adaptor loop won't do since it come
before the volume control.

One point worth mentioning: the "Pre-out" and "Main-in" under
discussion need not have "universal" characteristics, since they will
*only* be dealing with an active crossover (and perhaps an equalizer.)

It has been suggested by NSM: "post a circuit diagram and several of
us could tell you where to add them"

Here are the block ad circuit diagrams:
http://nom.de.plume.free.fr/temp_files/
The diagrams are for the TA-F590ES and a variant, the TA-F690ES.
The latter has a Pre-out, but no Main-in.
We are discussing here the TA-F590ES

(Please consider that the content of the files may be copyrighted.)

Thank you, in advance, for your contributions.

wrote in message
...
Trying to add a Main-in/Pre-out to a Sony amplifier:

The amplifier has an "adaptor loop" with bridged IN & OUT cinch(RCA)
connectors before the volume control.

The aim is to insert a 2-way active crossover, and resend the
high-range output to the Sony. The adaptor loop won't do since it come
before the volume control.

What will you do with the low out? I would do almost anything to use the
adaptor loop.

N

The low-out will go to a powered subwoofer.

(I don't really understand your statement " I would do almost
anything..." Just a problem with subtleties of English.)

On Sat, 22 Jan 2005 20:59:27 GMT, "NSM" wrote:

What will you do with the low out? I would do almost anything to use the
adaptor loop.

"SansAdresse" wrote in message
news
The low-out will go to a powered subwoofer.

(I don't really understand your statement " I would do almost
anything..." Just a problem with subtleties of English.)

OK.

"I would do almost anything..." == that is so easy and everything else is so
hard.

I use an unpowered subwoofer. For your case, I would tap the low off from
the speaker outputs, combine them and feed that to the powered subwoofer.
That way the remote vol control will still work as expected. I'd use two 100
ohm resistors feeding a 10 ohm resistor and connect the powered subwoofer
input to the connection point.

N

The idea is to cleanly separate the frequencies (I am just going by
the textbook!), and to avoid sending to the main speakers the low
frequencies which may drive them into distortion. (Bach's organ music
is played on the system.)

================================================

On Sat, 22 Jan 2005 23:38:00 GMT, "NSM" wrote:

The low-out will go to a powered subwoofer.

I use an unpowered subwoofer. For your case, I would tap the low off from
the speaker outputs, combine them and feed that to the powered subwoofer.
That way the remote vol control will still work as expected. I'd use two 100
ohm resistors feeding a 10 ohm resistor and connect the powered subwoofer
input to the connection point.

SansAdresse wrote:
The idea is to cleanly separate the frequencies (I am just going by
the textbook!), and to avoid sending to the main speakers the low
frequencies which may drive them into distortion. (Bach's organ music
is played on the system.)

You shouldn't have to worry about distortion in a subwoofer, but I admire
your fortitude. Yes, you are doing it the 'right' way, but certainly you
are doing it the 'hard' way. I'd try NSM's solution first, then if you have
objectionable distortion....

jak

================================================

On Sat, 22 Jan 2005 23:38:00 GMT, "NSM" wrote:

The low-out will go to a powered subwoofer.

I use an unpowered subwoofer. For your case, I would tap the low off
from the speaker outputs, combine them and feed that to the powered
subwoofer. That way the remote vol control will still work as
expected. I'd use two 100 ohm resistors feeding a 10 ohm resistor
and connect the powered subwoofer input to the connection point.