Rat Shck Presidian 40-5053. Next Sonic Impact?


I just bought a pair. Supposedly a guy from the Connecticut Audio Society bought a pair for his video system and couldn't believe how good they are. He was floored.

http://www.radioshack.com/product/index.jsp?productId=2104336&cp
petewhitley
Drubin,

I own the Ref. 3A DeCapos and these Presidians. There is no confusing the two! BTW, My Decapos which supposedly "have a single cap" on the tweeter, actually have 4 components in the crossover. It's strange: When I enquired with Divergent Technologies (Distributor for Ref 3A) they said there is "effectively" a single cap on the tweeter. Whatever that means!

Enjoy,

TIC
when i found my vintage hartley monitors, the crossover was the same, a single cap to an older cone tweeter with the mid-woofer running "wide open." the response of my friend who dabbles in speaker design was "ugh." the new tweeters and crossovers from hartley have three components (now four, i added a bypass cap), and the sound is now very acceptable to my tin ears. a similar upgrade for these little puppies naturally springs to mind.

funny about the deCapos and the use of language. sign o' the times......
Let's assume that each "element" (speaker, driver, whatever) actually behaves like an 8 Ohm resister.

Let's also assume that we're going to use 16 elements (instead of 14). It makes the math easier.

We need to recognize that resisters in series are simply additive:

R(1) + R(2) = R(3)

But resisters in parallel are not:

1/R(1) + 1/R(2) = 1/R(3)

So we'd arrange the elements into serial groups that are parallel to each other in attempt to keep the total resistance in an "ideal" range (around 8 Ohms).

If we used 16 speakers, we'd create 4 groups of 4 speakers and wire each of those 4 groups in series:

S(1) + S(2) + S(3) + S(4) = G(1) = 32 Ohms
S(5) + S(6) + S(7) + S(8) = G(2) = 32 Ohms
S(9) + S(10) + S(11) + S(12) = G(3) = 32 Ohms
S(13) + S(14) + S(15) + S(16) = G(4) = 32 Ohms

Now wire each of those groups in parallel:

1/G(1) + 1/G(2) + 1/G(3) + 1/G(4) = 1/Total = 8 Ohms
Though the total impedance might be 8 ohms, it would require too much voltage to put any decent amount of power to each one; they'd all be coasting along-
Nrenter's recommendation of side placement with inboard tweeters and toe-in was a good one IMHO. still wondering about upgrading the tweeters though, but need to start doing my homework first.