[paulram]

Hello Everyone here at ACIs forum. I am new here , discoverd this forum while trying to contact ACI on the net. Back in the late 80,s I built many kits for my friends ordered from ACI. These included  the Model C , S , G2 , Pulse subs and a Compact Monitor which I still use today on a daily basis ( the CM uses Dynaudio drivers , 17W75 woofers and D28AF tweeters. Its hard to believe its been over 20+ years! In any case , I removed the drivers today to see if the foam insulation had deteriorated and sure enough it had lost its consistency..so its time for replacement. I was wondering also if those polyprop Solens need replacing. There are three in all on the x-over board. One is a 20uf and the others are 7 uf each in a paralled config , just wondering why? My theory is that a final value of 14 uf was needed in the design and a single value was not available at that time..care to comment any one? Also does any one know the values for the coils an resistors? How can I increase the output of the tweeter..is that by decreasing the resistor values and if so which ones and by how much. This is a personal preference , seems I am losing my ability to hear some high freqs (lol) What is the x-over point?thanks Paul

[Mike Dzurko]

Hello and welcome

Personally, I'd leave the crossovers alone. Those parts are good for many more years, and they were optimized for those speakers. Feel free to experiment if you want. Might make it sound different, but not necessarily better. If you want a bit more tweeter, you'll have to reduce the total amount of resistance. After this long, I sure don't remember the exact crossover, but typically the resisters formed an L-Pad to cut the tweeter output. Or possibly there is only a series tweeter. In that case, lowering the value will increase tweeter output, but also change the crossover.

[Paul Ramdial]

Thankyou Mr Dzurko. The resistors are indeed in an lpad configuration.

[Mike Dzurko]

Paul:

Google will give you lots of options for L-Pad calculators you can use to get less attenuation (more output) from the tweeter. Here's the first one that pops up:

http://www.sengpielaudio.com/calculator-Lpad.htm