Help, Please

[genek]

The 4xa crossed over at 1600Hz, but I don't think we have a crossover schematic, so no idea if there was a change there or if it's all because of the tweeter change from the 4x.

[michiganpat]

The 4xa crossed over at 1600Hz, but I don't think we have a crossover schematic, so no idea if there was a change there or if it's all because of the tweeter change from the 4x.

FWIW, the 17/18, and 18S/28S had a single 6uf cap for a high pass, and the woofer ran wide open...IIRC the B's dropped the cap to a 5uF

[HarryM]

I don't want to step on any toes and this is an older thread but based on my research on my 28s and info provided to me they used a dome tweeter and a 8uf cap.Just wanted to clarify.

[Rlowe]

_{Hello HarryM -}

_{Just for the record, the AR28s xover shows}

_{- an 8uF cap in series with the Tweeter and}

_{- an 0.46mH coil in parallel with the Woofer.}

_{I have attached the assembly and xover diagrams to your other posting for AR25 & AR28S information.}

_{From the diagrams the AR25 used the 200014-3 tweeter and has a 6uF cap in series with the tweeter.}

_R

[HarryM]

Thanks Rlowe,I found them and am going to be ordering new caps and hopefully it fixes the problem.

Thanks again,Harry.

[Pete B]

I'd be curious to hear the EPI 100 drivers and crossovers in the AR-4x box, lol!

[michiganpat]

I don't want to step on any toes and this is an older thread but based on my research on my 28s and info provided to me they used a dome tweeter and a 8uf cap.Just wanted to clarify.

no problem....I was kinda guessing with the 28s, as I thought the "17" (ADD series AR4/4x/4xa sized speaker) was replaced/renamed "28s" with the S series, like the 18S superseded the 18, looking at the LS/B series brochure on this site, the 28B is exactly that--the same drivers as the 18B in a 4ish sized cabinet..

[Pete B]

I would be more inclined to go with Zilch's recommendations for the 4x before anything else. My brief experiment with the HiVi simply affirmed that a larger dome tweeter can be probably be used with the 4x without much (or, possibly, any) crossover change. The Parts Express Dayton 1 1/8" dome has also been favorably mentioned.

We've gotten way off the topic. This should be continued in the mods, tweaks, and upgrades section of the forum.

Roy

People, don't forget the excellent 4x mod by David Smith:

http://www.classicsp...opic=5815&st=80

For those who are not familiar with David, he was:

• Director of Product Development at PSB Speakers/ Lenbrook Inc
  
• President and Chief Engineer at Snell Acoustics
  
• VP of Engineering at a/d/s/
  
• Manager of Loudspeaker Development at McIntosh Laboratories
  
• Sales trainer/National Sales Manager at KEF America/Meridian America
  
• Senior Development Engineer at KEF Electronics
  
• Transducer Engineer at JBL Professional
  

Here is his Linkedin page:

http://www.linkedin....smith/5/496/a69

[michiganpat]

Pete- that's assuming you can find 4x tweeters in good shape?

[HarryM]

Michiganpat I'm glad to hear it's not a problem and the 28s does seem to be the odd one out.It does share the tweeter with the 48s and the woofer with the 18s.Kind of like it was cross bred.