[Julio Castro]

Hello everybody:

Hi,

I'm looking for put a graphic equalizer between my CD player and the
amp. Specifically, I haven't yet decided between the dbx
231(http://www.dbxpro.com/231.htm) or the dbx 1231
(http://www.dbxpro.com/1231.htm)

As many of you shoul know such processors have only balanced XLR/TRS
connectors, nevertheless their manual claim to be able to handle
unbalanced connections.

So far I understand that I can make my own balanced-to-unbalanced
cables easily, and also, that it's better to use a transformer isolated
connection in my case.

Nevertheless, I'm most concern about the impedance and input signal
compatibilities. As I understand impedance diferences between
equipments may lead to signal degradation, noise and in the worst case
to damage in the equipment.

So I'm asking your kind help in order to find (or maybe build) the
equipment that shall connect both systems perfectly. I want the signal
to be perfect on, in order of preference, quality, impedance and
voltage.

What do I need for the job?


Specifications of CD player and amplifier input signal a
Sensivity: 150 mV
Impedance: 50 kilohms
amp: S/N (78' IHF): 82 dB (A, 150mV(Weighted network, input level))

Specs of the dbx 231 (and 1231) a
Inputs
Connectors: 1/4" TRS, female XLR (pin 2 hot)
Type: Electronically balanced/unbalanced, RF filtered
Impedance: Balanced 40kohm, unbalanced 20kohm
Max Input Level: +21dBu balanced or unbalanced
CMRR: 40dB, typically 55dB at 1kHz
Outputs
Connectors: 1/4" TRS, male XLR (pin 2 hot)
Type: Impedance-balanced/unbalanced, RF filtered
Impedance: Balanced 100ohm, unbalanced 50ohm
Max Output Level: +21dBu balanced/unbalanced into 2kohm or
greater
+18dBm balanced/unbalanced (into 600?)

Any comments are welcome
Thanks
JC

[TimPerry]

Julio Castro wrote:
Hello everybody:

Hi,

I'm looking for put a graphic equalizer between my CD player and the
amp. Specifically, I haven't yet decided between the dbx
231(http://www.dbxpro.com/231.htm) or the dbx 1231
(http://www.dbxpro.com/1231.htm)

As many of you shoul know such processors have only balanced XLR/TRS
connectors, nevertheless their manual claim to be able to handle
unbalanced connections.

look real close at the rear view. also see specs below and not 1/4" inputs
and outputs.



So far I understand that I can make my own balanced-to-unbalanced
cables easily, and also, that it's better to use a transformer
isolated connection in my case.

Nevertheless, I'm most concern about the impedance and input signal
compatibilities. As I understand impedance diferences between
equipments may lead to signal degradation, noise and in the worst case
to damage in the equipment.

So I'm asking your kind help in order to find (or maybe build) the
equipment that shall connect both systems perfectly. I want the signal
to be perfect on, in order of preference, quality, impedance and
voltage.

What do I need for the job?

four 1/4" to RCA adaptors or 1/4" to RCA cables



Specifications of CD player and amplifier input signal a
Sensivity: 150 mV
Impedance: 50 kilohms
amp: S/N (78' IHF): 82 dB (A, 150mV(Weighted network, input level))

Specs of the dbx 231 (and 1231) a
Inputs
Connectors: 1/4" TRS, female XLR (pin 2 hot)
Type: Electronically balanced/unbalanced, RF filtered
Impedance: Balanced 40kohm, unbalanced 20kohm
Max Input Level: +21dBu balanced or unbalanced
CMRR: 40dB, typically 55dB at 1kHz
Outputs
Connectors: 1/4" TRS, male XLR (pin 2 hot)
Type: Impedance-balanced/unbalanced, RF filtered
Impedance: Balanced 100ohm, unbalanced 50ohm
Max Output Level: +21dBu balanced/unbalanced into 2kohm or
greater
+18dBm balanced/unbalanced (into 600?)

Any comments are welcome
Thanks
JC

[Laurence Payne]

Just make the simplest possible connections. Phono mono jack from
CD to eq, probably the same from eq to amp.

Don't expect miracles. If there IS a fault in your system that
requires eq, it is probably best addressed by speaker choice, speaker
positioning and/or room treatment. Static eq can be useful for
achieving higher gain before feedback in pa systems. But this is at
the expense of fidelity.

[Geoff]

Julio Castro wrote:
Hello everybody:

Hi,

I'm looking for put a graphic equalizer between my CD player and the
amp. Specifically, I haven't yet decided between the dbx
231(http://www.dbxpro.com/231.htm) or the dbx 1231
(http://www.dbxpro.com/1231.htm)

As many of you shoul know such processors have only balanced XLR/TRS
connectors, nevertheless their manual claim to be able to handle
unbalanced connections.



What do I need for the job?

First you need to rationalise why you feel a graphic EQ there at all. Then
I would be inclined to find a unit with the same type of inoputs/outputs as
the rest of your gear.

geoff

[Karl Uppiano]

"Julio Castro" wrote in message
oups.com...
Hello everybody:

Hi,

I'm looking for put a graphic equalizer between my CD player and the
amp. Specifically, I haven't yet decided between the dbx
231(http://www.dbxpro.com/231.htm) or the dbx 1231
(http://www.dbxpro.com/1231.htm)

As many of you shoul know such processors have only balanced XLR/TRS
connectors, nevertheless their manual claim to be able to handle
unbalanced connections.

Then there is no problem.

So far I understand that I can make my own balanced-to-unbalanced
cables easily, and also, that it's better to use a transformer isolated
connection in my case.

Yes, and no. A high quality transformer would be expensive and unnecessary
unless you plan to string the cables a very long distance, which would be
why you might consider balanced lines in the first place. Lots of modern
balanced equipment doesn't use transformers these days anyway. They use
op-amps.

Nevertheless, I'm most concern about the impedance and input signal
compatibilities. As I understand impedance diferences between
equipments may lead to signal degradation, noise and in the worst case
to damage in the equipment.

Impedance should not be a concern. These days, output impedance is usually
low; input impedance is usually high - both for pro and consumer gear. Audio
lines are not transmission lines requiring matched impedance. Pro signal
levels are usually +4 or +8 dBm; consumer gear is sometimes -10 dBm. This is
not a big enough difference to cause damage, but pro gear might overload the
consumer gear. Similarly, the consumer gear might not have enough output to
drive the pro gear without a booster amplifier.

So I'm asking your kind help in order to find (or maybe build) the
equipment that shall connect both systems perfectly. I want the signal
to be perfect on, in order of preference, quality, impedance and
voltage.

What do I need for the job?

http://www.rdlnet.com/product.php?page=43
http://www.rdlnet.com/product.php?page=45
http://www.tieline.com/Tieline_04/Pr...ons/AC200.html
http://www.tieline.com/Tieline_04/Pr...ons/AC400.html

Specifications of CD player and amplifier input signal a
Sensivity: 150 mV
Impedance: 50 kilohms
amp: S/N (78' IHF): 82 dB (A, 150mV(Weighted network, input level))

Specs of the dbx 231 (and 1231) a
Inputs
Connectors: 1/4" TRS, female XLR (pin 2 hot)
Type: Electronically balanced/unbalanced, RF filtered
Impedance: Balanced 40kohm, unbalanced 20kohm
Max Input Level: +21dBu balanced or unbalanced
CMRR: 40dB, typically 55dB at 1kHz
Outputs
Connectors: 1/4" TRS, male XLR (pin 2 hot)
Type: Impedance-balanced/unbalanced, RF filtered
Impedance: Balanced 100ohm, unbalanced 50ohm
Max Output Level: +21dBu balanced/unbalanced into 2kohm or
greater
+18dBm balanced/unbalanced (into 600?)

Any comments are welcome
Thanks
JC

[Arny Krueger]

"Julio Castro" wrote in
message
oups.com
Hello everybody:

Hi,

I'm looking for put a graphic equalizer between my CD
player and the amp. Specifically, I haven't yet decided
between the dbx 231(http://www.dbxpro.com/231.htm) or the
dbx 1231 (http://www.dbxpro.com/1231.htm)

As many of you should know such processors have only
balanced XLR/TRS connectors, nevertheless their manual
claim to be able to handle unbalanced connections.

Not universally true. For example, some Rane graphic eqs have both pro and
RCA connectors.

So far I understand that I can make my own
balanced-to-unbalanced cables easily,

Please see for the usual reference in this area:

http://www.rane.com/note110.html

and also, that it's
better to use a transformer isolated connection in my case.

In all liklihood - unecessary.

Nevertheless, I'm most concern about the impedance and
input signal compatibilities. As I understand impedance
diferences between equipments may lead to signal
degradation, noise

Shouldn't be a problem, as signal levels out of a CD player are typically
not all that dissimilar from pro audio conventions. Putting the eq in the
tape loop of a home system could be a different situation.


and in the worst case to damage in the equipment.

No way!

So I'm asking your kind help in order to find (or maybe
build) the equipment that shall connect both systems
perfectly. I want the signal to be perfect on, in order
of preference, quality, impedance and voltage.

What do I need for the job?

Simple cables or adaptors.

Specifications of CD player and amplifier input signal a
Sensivity: 150 mV
Impedance: 50 kilohms
amp: S/N (78' IHF): 82 dB (A, 150mV(Weighted network,
input level))

These are for just the integrated amp, right?

Specs of the dbx 231 (and 1231) a
Inputs
Connectors: 1/4" TRS, female XLR (pin 2 hot)
Type: Electronically balanced/unbalanced, RF filtered
Impedance: Balanced 40kohm, unbalanced 20kohm
Max Input Level: +21dBu balanced or unbalanced
CMRR: 40dB, typically 55dB at 1kHz
Outputs
Connectors: 1/4" TRS, male XLR (pin 2 hot)
Type: Impedance-balanced/unbalanced, RF filtered
Impedance: Balanced 100ohm, unbalanced 50ohm
Max Output Level: +21dBu balanced/unbalanced into
2kohm or greater
+18dBm balanced/unbalanced (into 600?)