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Ricpan
04-16-2020, 07:40 AM
I'm in the process of upgrading my crossovers high and mid range capacitors to Clarity CSA and Jantzen superior z. When I built these a few years ago I ran the negative from the 9v battery outside the box to a ground source. Is this the best way to do it?

robertg
04-16-2020, 09:21 AM
Wouldn't it be way easier to run it to the negative on the actual crossover board? I can't see it making any difference, ground is ground.

Ricpan
04-16-2020, 10:56 AM
I wasn't sure I'm just a hack that can read a schematic and copy what others have done. I was thinking maybe better to ground away from signal path.
Wouldn't it be way easier to run it to the negative on the actual crossover board? I can't see it making any difference, ground is ground.

Flodstroem
04-16-2020, 03:59 PM
I wasn't sure I'm just a hack that can read a schematic and copy what others have done. I was thinking maybe better to ground away from signal path.

The battery is floating on the signal path. No ground loops or other mystic thing can happen. Also the battery adds only voltage over the caps by a very large resistance (1 Meg or so), no power is involved. I should have done it as robertg suggests :)

Ian Mackenzie
04-16-2020, 05:15 PM
I'm in the process of upgrading my crossovers high and mid range capacitors to Clarity CSA and Jantzen superior z. When I built these a few years ago I ran the negative from the 9v battery outside the box to a ground source. Is this the best way to do it?

As long as you only have one connection from the battery negative terminal to the crossover negative terminal at the input you are fine.

Each capacitor junction should have its own + positive wire in series with a 2 -3 Meg ohm resister. The other side of the resister goes to the battery + positive.

Leave the battery ON all the time.
The capacitors take a few minutes to charge up.

On a practical level tension then builds up on the foil dielectric windings minimising foil chatter which otherwise modulates the capacitance blurring the sound. The dc voltage also biases the capacitor creating the so called zero crossing class A operation (refer to JBL literature M9500)

If you ever wondered is that a myth run the crossover into a dummy load with a music signal. You can hear the capacitors “sing”. It’s not rocket science. Valve amplifiers have very high DC bias voltages and the dc blocking capacitors are charge coupled the same way. Spare a thought for why valve preamps have that distinctive revealing sound.

Ricpan
04-17-2020, 11:48 AM
As long as you only have one connection from the battery negative terminal to the crossover negative terminal at the input you are fine.

Each capacitor junction should have its own + positive wire in series with a 2 -3 Meg ohm resister. The other side of the resister goes to the battery + positive.

Leave the battery ON all the time.
The capacitors take a few minutes to charge up.

On a practical level tension then builds up on the foil dielectric windings minimising foil chatter which otherwise modulates the capacitance blurring the sound. The dc voltage also biases the capacitor creating the so called zero crossing class A operation (refer to JBL literature M9500)

If you ever wondered is that a myth run the crossover into a dummy load with a music signal. You can hear the capacitors “sing”. It’s not rocket science. Valve amplifiers have very high DC bias voltages and the dc blocking capacitors are charge coupled the same way. Spare a thought for why valve preamps have that distinctive revealing sounbuiltd.
Thanks Ian, I built my crossovers a couple years ago and have been very happy. During the virus I decided to upgrade my caps on the mid and high with Carity and Jantzen. When I originally built the crossovers I ran to outside ground not knowing any better.