Hello I have a mint pair of CD8s in oak and have a a few questions regarding upgrading caps and resistors. In the first picture you can see they installed two 60 mfd caps Is there a reason for this or can i just replace with a single 120 cap? They also installed two 1 ohm resistors in parallel. should I install new 1ohm resistors the same way?
On the bank of resistors on the left side should they remain the same 1.5 and 2 ohm or can they be replaced with all the same ohms (1.5 or 2 )
These are great sounding speakers but lack a little punch compared to my Allison 7
On the bank of resistors on the left side should they remain the same 1.5 and 2 ohm or can they be replaced with all the same ohms (1.5 or 2 )
These are great sounding speakers but lack a little punch compared to my Allison 7
Attachments
If the 60s are in series, use a 30. If they are in parallel, use a 120. Keep the voltage and type of the caps the same.
They were tune with that type, and the filter knees and slopes will change with different types.
The resistors are fine, none are burnt, they will not change with time.
They were tune with that type, and the filter knees and slopes will change with different types.
The resistors are fine, none are burnt, they will not change with time.
Are you talking about the two small blue components? Could they be small value capacitors?
You say "first picture" - did you mean to attach a second one?
I agree with boswald that there's no need to change the resistors. Simply replace all electrolytic capacitors with good quality equivalents.
The small blue components might be polyswitches, just a different brand of the orange polyswitch discs shown in the picture of the crossover provided by Galu
Yes, afa, I agree that is a distinct possibility.
Whatever they are, they should be re-installed when the capacitors are replaced.
Whatever they are, they should be re-installed when the capacitors are replaced.
Thanks, but I'd really like to know if it was those little blue components you measured as having a resistance of 1 ohm.
If so, they are Positec (Polyswitch) speaker protection devices. These have a low resistance of around 0.6 ohm under normal operation, but switch to a high resistance to protect the drivers if a prolonged overload occurs. They then revert back to 0.6 ohm after the overloading is stopped
A 0.6 ohm Polytech will measure more like 1.0 ohm when you add on the resistance of your multimeter leads.
Make sure you include them in your crossover renovation. Don't look to replace them as they come in a bewildering variety of specifications.
Any further questions, don't hesitate to ask. Happy renovating!
If so, they are Positec (Polyswitch) speaker protection devices. These have a low resistance of around 0.6 ohm under normal operation, but switch to a high resistance to protect the drivers if a prolonged overload occurs. They then revert back to 0.6 ohm after the overloading is stopped
A 0.6 ohm Polytech will measure more like 1.0 ohm when you add on the resistance of your multimeter leads.
Make sure you include them in your crossover renovation. Don't look to replace them as they come in a bewildering variety of specifications.
Any further questions, don't hesitate to ask. Happy renovating!
Thanks for setting my mind at rest and for the belated second pic! 😎
Stick to the electrolytics and you shouldn't be disappointed.
P.S. It's an interesting experiment to recap one crossover first then compare the sound of that speaker with the sound of the unrenovated one.
Stick to the electrolytics and you shouldn't be disappointed.
P.S. It's an interesting experiment to recap one crossover first then compare the sound of that speaker with the sound of the unrenovated one.
I agree I recapped my Polk Monitor 10As I have 4 of them I did two first and waited a few months to break in. I can tell you it definitely was worth it I heard things on certain recordings that I did not hear before. More punch tighter bass I did the caps on the other two and now enjoy them all