Modifications to the RTA 15TL

Thank You very much Westmassguy ... and Happy Easter tu all the Forum
Steve

Dear all I've a question who may know. I find a Munford Supreme but non with the exactly capacity. Can I use 1 X 10 UF caps + 1X1.8 uF for the 12Uf Cap and 1X10 uF + 3.3 uF for the 13.5 uF in this crossover? Also can I leave in place and use the original 1.75 mH? I will change only the 022mH with a new one. Thank You very Much

Grazie :-) thank you very much
Steve

Pegaso55 wrote: »

Dear Westmassguy before start to assembly the xover I've a last question, for the resistor (I find 0.47 ohm instead 0.5) is better 10w or 5 w ? Or they have the same effect?
I thank you in advance
Steve

.47 ohm 10 watt

First Step ... Done! :-)
But I do not know why I can not publish the photo :-)

All point to point, very nice. Two things, the type of bolt you used to secure the large Inductor, and the Sandcast resistors. If the bolt is stainless steel you're good. If its regular steel, you've increased the value of the inductor. I would have used Mills, or Mundorf MOX Resistors.

[img][/img]
[img][/img]
[img][/img]
[img][/img]

The 0.5 ohm resistor is in series with only the tweeter circuit.
Before closing I covered the xover with a thin layer of soundproofing.
Now the sound is incredible ... amazing ... wonderful
I want to thank all of you for the advice
Thanks a lot from Italy

westmassguy wrote: »

http://forum.polkaudio.com/discussion/48075/modifications-to-the-rta-15tl/p1



Parts list:
2 x 13.5uF caps
2 x 12uF caps
2 x 10uF caps
2 x 1.75 mH, 16 awg inductors
2 x 0.22 mH, 19 awg inductors
2 x 2.7 ohm resistors
2 x 0.5 ohm resistors

If i would do as the picture states, i would end up with the 13500uf on the tweeter side. C2 and C3 is switched in the drawing. Or is it just my late -92 RTA15-TL thats different?

westmassguy wrote: »

Did Polk switch to a smaller, square circuit board on your 15tls? Trace the circuit. The 13.5uf is the shunt in the low pass circuit.

Yes they have the small square board, the shunt is named C2 on this one.

Hey. Those look fimiliar maybe one day soon i will put em in & see how they sound. Im a slacker

Ive been painting for 2 days straight & im outside sweating like a pig in heat. Im so backed up between work & the house. If i live to see it all done i will be a happy man

westmassguy wrote: »

It's Wicked Hawt"....
Try working with a house full of non-English speaking relatives for two weeks.

Try restoring a couple of Polk speakers when you live in Sweden.
Those crossovers look really neat, thats the look i'm aiming for.

Well, now the speakers are back in action with redone x-overs and new tweeters. The short listeningsession iv'e done is promising!

This is how the X-overs look redone:

westmassguy wrote: »

Looks great. Did you remember to reverse polarity on the tweeter leads?

Of course!

Did also replace all the internal wires, same gauge but new single core wire. Stranded wires tend to give a bit more resistance.

So the modifications continue.

Now it's time to give the estetics of the speakers an upgrade. It seems to me like the grilles look a bit to much 90's , so i started making new ones. Hopefully they will end up looking a bit more 20-th century. The original design does actually have a design flaw, which is when the fabric covering the frame is mounted, it tends to make the sides of the grille bend towards the center of the speaker (looking like a banan), so i added some extra bracing to the new ones.





The new ones wont be having any angle cut sides/bottoms/tops, just rounded right/left edges and they will be mounted flush with the sides and top of the speaker. This modification won't show any of the veneer when you are standing/sitting right in front.
I'm also thinking about adding a newer badge/emblem, prefferably aluminium colored, or the black/white/red one.

And well, i swapped the 90's looking feet to new black aluminium ones (44x17mm round with a rubber insert)