Selenium D250X

[cheric]

Through my research (reading these threads), I have learned that K-55 series could be replaced with the Selenium D250X; but someone also mentioned that I need to install a Mills 8 ohm 10 watt non-inductive resistor on the Xover.

Do I need to mod the Xover with the resistor and where would it go? Would it make a major difference in performance?

Thanks for the help.

[Guest David H]

Through my research (reading these threads), I have learned that K-55 series could be replaced with the Selenium D250X; but someone also mentioned that I need to install a Mills 8 ohm 10 watt non-inductive resistor on the Xover.

Do I need to mod the Xover with the resistor and where would it go? Would it make a major difference in performance?

Thanks for the help.

Welcome to the forums.

The K-55 is a better performer IMO than the Selenium. What speaker is this going in?

I would think because of the impedence you could just drop down a single tap on the autoformer, the series resistor would not be needed.

The D-250X is really not a direct replacement for the K-55 as it will not go anywhere near as high as the Atlas driver. You will probably need to change your HF driver and change your crossover to cross the HF at 4500hz. Bob crites has crossovers and tweeters for you application.

Dave

[cheric]

GotHover, thank you for a quick reply!

I have a set of HI (1982) originally with K77s, K55s and K24s but a few weeks ago with the help of KG4GUY (thank you K.), I changed the tweeters to APT50 and liked the sound very much. Now, I am thinking about changing the mid's with the Selenium drivers. Not being an expert at electronics, I just want a shortcut by using the resistor. Just wasn't sure exactly where to "put it". In between the + and - of the squawker wires, I guess.

just drop down a single tap on the autoformer... could you just give me the tab number instead?

These drivers are priced reasonable enough to experiment.

I "have been" with Klipsch for the last 10 years or so, just never get in to the technical part of it much, only lately.

Would you believe, in one year, I acquired 5 pairs of Klipsch speakers (2-H1's, 1-H2 and 2-ForteII's) and sold ALL my Reference Series.

[Guest David H]

These drivers are priced reasonable enough to experiment.

If you already have a good pair of K-55's I would stick with them, I think you will find them suprior to to most of the resonably priced options currently available.

[Lime Twig]

I run 4 La Scalas: 2 original industrials and 2 hybrids made up of Industrial LS woofers plus a top-box I built. It's loaded with a K-400 horn with a Selenium D250X mid and a Selenium ST324 slot tweeter. The crossovers on the second ones were built up by some local folks. When we first turned them all on my impression was they were remarkably similar. After a bit more listening, I realized the new ones were a bit quiter. Our crossover builder informed me that he had lowered the output of the mids by 6db because the D250X was louder than the K55. He had initially planned to only lower it by 3db but had decided on 6 at the last minute. Turns out 3db is right and he offered to change it for free.

There may well be differences between the sound of the two drivers but in my experience so far, it's very subtle.

And man, those Selenium drivers are CHEAP![]

There's a more noticable difference between the tweeters for sure. The Seleniums sound like they go higher. I wouldn't say I like either one better, I'd say the K77 "sizzles", whereas the ST324 "rings". Both are very pleasant to my ear.

Happy experiementing!

[bigrfish]

At one point I just covered up the tweeter horns on my H-1's with duct tape....that settled them down quite a bit.

There are ends and there are means....Chuck

[Groomlakearea51]

Having experimented for a number of years now with the D250X and Heresy's, I can say that the better combination is the D250X with the CT125 tweeter and an E/4500 crossover. You can attenuate the 250 with either an inline resistor, or simply drop the tap down. The D250X works ok with the K-77, but the CT-125 works better.

My "favorite" Heresy is K-28's (or CW-1228's from Bob), D250X on a 42011065 (parts express) plastic 1" throat wide dispersion horn (same flare face dimensions as K-700), CT-125's and E4500 with the mid tap correction as opposed to the inline resistor.

Just some IMHO's....