Doubt with Active Sub Controller

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
I'm looking at my P48 PCB and I see spaces for 9 caps and the circuit diagram shows 4. I wrote to Mr. Elliot asking for additional info re: the caps. He said the information is available on the secured sight which I have not yet found.
There are two caps #C7 and #C8 that are definitely the size and shape of filter caps.
What is the secured site he mentioned? Anybody know?
 
And! I've asked for an active sub filter schematic here and the replies i got where about taking a look to that schematic, which is useless since there are parts missing. I need one of those filters, which also sum up left and right channels. Does anyone have a COMPLETE, WORKING schematic for a sub filter?
 
OK, so first off you need to understand that P48 is probably not what you want unless you read the article very carefully and understand exactly how the circuit is designed to be used. It is not a simple crossover, it is primarily a very special EQ designed for use with a specific type of subwoofer. That is, a subwoofer which has been intentially built into a box that is "too small" (according to traditional design methods) so that its resonant frequency is higher than the frequencies it will be used at. If you try to use this circuit with a conventional subwoofer, you will not only be disappointed with the performance, but will also be likely to damage your subwoofer.

There are no fewer than 3 crossover projects on Rod's site, any of which could be used as a subwoofer crossover after the correct filter component values are chosen. In general, Rod's projects' schematics do not include a power supply, but he usually refers the reader to one of his power supply projects. In addition he rarely includes (necessary) power supply bypass capacitors in his schematics, but he includes them on his PCBs. Usually, all that you need to do is add a 10 uF 25 V cap between each of the two power rails and ground (one pair for each opamp), noting correct polarity of course. Other than that the circuits he puts up are generally functional as described in the articles.
 
Problem solved

My PCB mailer was supposed to contain a "user name and password" but it did not. I emailed Rod Elliot again and he gave me the needed protocol to access the "Secure Site". Once in the secured site a very complete circuit diagram and photo along with assembly instructions are there. All the information you'd ever nee
d to assemble, test, and install are included.
Mr. Elliott requests that all customers respect and protect the Secured Site.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.