"Bypass" Capacitors in Crossovers

[Deang]

The paste in the caps dried up, what did you replace them with?

Yes Dee, either two 8uF electrolytics or an 8uF and 16uF (depends on age, they made adjustments to the crossover in the later models).

[Daddy Dee]

Thanks Dean. The Advent project is being pushed out farther. moving in June.

appreciate your mentioning this. i want to remember this when i rebuild those crossovers.

[mike stehr]

The paste in the caps dried up, what did you replace them with?

Those red "Audiophiler" brand 3% metal polypropelenes.

[Guest David H]

Ever listen to an Original Advent Loudspeaker, Dynaco A25, AR-3, or Dahlquist DQ-10. All very popular speakers at one time and people still use them. Want to know what happens to their sound when you start mucking with their caps and coils?

I know first hand this is true, I rebuilt a pair of DQ-10's. I replaced the Mylar Caps with Metalized poly, this had minimal bearing on the sound, However on the second phase of the upgrade, I decided to replace the inductors with heavy gauge low ESR inductors....Big mistake, I had to go back and retrace my steps several times to find the issue. When I measured the ESR of the inductors I found these had in excess of 2 Ohms resistance.

When all was said and done I had to De Q the inductors by adding series resistance to match the resistance of the original coils.

In this case Dahlquist took the ESR of the components into consideration while building this Rube Goldberg crossover as would any good designer.

[Guest David H]

Another, notice the ESR at the bottom, 2.4 Ohms. By replacing this with a quality inductor of approximately .3 Ohms I effectively shifted the crossover point and increased the sound pressure level of the driver in the circuit..

[Guest David H]

This inductor here is quite the GEM. This was in the Piezo super tweeter circuit so it went in the trash with the tweeters.