• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Advent Large Recap

L

Lexfer

New Member
Good morning, I am trying to recover my old Advent Large Utility speakers (x4) and after much reading I have several doubts that I hope to be able to resolve with your valuable collaboration.

Regarding the Crossovers, mine are Rev2. and according to the technical details the capacitors must be 16uF 50v NPE and 8uf 50v NPE.
2 - Web.jpg

In my city (Bogota, Colombia) I have searched for them without any positive results.

On Amazon abroad my search has been useless and in a famous Chinese store I have found these 15uf 50v ones, does it work as a replacement for the 16uF 50v NPE?

15uF -50v - Web.jpg

I have no knowledge of electronics but I suppose that with the help of my son who knows how to do soldering work we can get this small project going.

Any information or help of course will be very grateful on my part. Greetings.
 
Register to hide this ad
Excellent!...I will look for the 8uf ones and then analyze which combination is easier to install..

Another concern is that I found 16uf ones but they are 100v (originally 50v) and I was wondering if this increase in voltage is a problem for considering them as an option.
 
Lexfer said:
Another concern is that I found 16uf ones but they are 100v (originally 50v) and I was wondering if this increase in voltage is a problem for considering them as an option.
Click to expand...
The increased voltage rating is NOT a problem when the capacitor is used passively. The Solen film caps I have in my Advents are rated for 400 volts, it's the capacitive value that is important when used in a passive crossover.
 
malden said:
How do the speakers sound as they are?
Click to expand...
Right now of the four only one of the frequency switch works correctly ; its sound is clear and crisp in "extended" but the other 3 switches do not make any change and their sound is cloudy and dull.

I have already performed the step of applying contact cleaner to the switch without any positive change and that is why my focus now is changing the capacitors.
 
a_retent said:
The increased voltage rating is NOT a problem when the capacitor is used passively. The Solen film caps I have in my Advents are rated for 400 volts, it's the capacitive value that is important when used in a passive crossover.
Click to expand...
I assume then that this crossover is passive and the 16uf 100v option is perfectly valid. Great information.
 
Any voltage rating equal or higher than original is fine.
If switch positions don't work, check the resistors.
Always replace Rockwood brand resistors, they are prone to failure.
15 or 16 uF is fine.
 
Pete B said:
Any voltage rating equal or higher than original is fine.
If switch positions don't work, check the resistors.
Always replace Rockwood brand resistors, they are prone to failure.
15 or 16 uF is fine.
Click to expand...
I never thought about resistors, I would think that any current brand would perform better than the Rockwood of the original Advent.
 
Gentlemen, as soon as my spare parts have arrived I have begun the restoration of my Advent crossovers; initially a single speaker to compare the result with the only one of the 4 that is working correctly with the frequency selector.

Remembering that this is my first time applying solder this is the physical result of changing capacitors and resistors.

20241216_134106.jpg

The result has not been what was expected unfortunately since there is no change in the sound and it also has no effect when using the frequency switch. To rule out possible problems I have changed the twitter between the two speakers and the result is the same. I should note that before changing the resistors I have measured them with the multimeter and none have reported any failures, even so I changed the one that you can see in the photo of the repaired crossover.

At this point I show you this photo of one of the crossovers that I have not repaired where a resistor appears with a strange stain that would indicate a malfunction but when measuring it with the multimeter it passes the test and gives the same data as the new resistor, however, as a precaution it will also be a reason for change.

Resistencia Xover3 quemada.jpg

20241216_134335.jpg

Gentlemen, to continue with the attempt I have thought of two things. 1. Eliminate the frequency switch since I have found in other readings that it does not have a major advantage and by doing so perhaps the 4 tweeters have a more balanced sound but this is a point that I have not seen described in any article and I would appreciate your help to be able to do it.

2. I have thought that perhaps it is the opposite and that the Crossover that sounds much brighter than the other 3 is the one with the problem although its sound is the one I like the most but I do not know to what extent my logic has something reasonable.

For now I remain pending waiting for your recommendations and the path to take. Thank you.
 
What may well be happening is your hearing itself. Not as sensitive enough to tell a difference. I never IIRC could tell much of a change when flipping the switch on most gear. Could be just me on tube gear can tell somewhat of a change. Could just be in my head too.

You have the parts so replace them and go on is what I suggest. Leaving the switch connected.
 
You must log in or register to reply here.
Back
Top Bottom