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I have an old set of Utah Heritage HS1-C. They actually sounded pretty interesting when i first got them...but a little muddy...nice alnico mid and a little plastic tweeter horn...very beefy bass. The x over consisted of one resistor and one small capacitor...50 v...and a pot. I took the cap off and it was just dead...same for the other... The cabinets are really good...very very solid. I just want to hear what they might sound like if they had even a modest working x over before I give them up for dead. Looking for ideas. The cap that came off didn't have a uf value...just a 4--- 50 vdc. Would start with just replacing it if I could determine the value...but I would like ideas on a real x-over if anyone with knowledge thinks it's worth doing.

First of all, determine that the woofers and tweeter(s) are in proper working condition, before proceeding...

the cap marked 4.....50V would be a 4 uF (approx.) 50V unpolarized electrolytic. So, for an 8 ohm system, this would be good for around 5KHz (we'll get to this later)

If you can determine (or guess) the original crossover point, then Parts Express, has a lot of crossover design information, and parts,
ranging from components of really cheap, up to richly elegant quality. The original el-cheapo caps these speakers used were inexpensive non-polarized
electrolytics, which sounded poor to bad from the git-go... The tweeter level pots are usually inexpensive wire-wound and can, and generally do, corrode and
go bad (usually poor wiper contact) over the decades. Even the pricey AR3As and AR4s had WW tweeter pots, which always died after about 20 years.

Capacitive reactance is an easy formula, Xc(in ohms) = 1,000,000 2*Pi * F * C (in Hz and uF)), or in simplified form, 159,250 / F*C

Referring to the Parts Express printed catalog, (speaker building section) for a 6dB/Octave crossover, as an example, 8 ohms and 1 KHz,
L would be 1.27 mH and C would be 19.9 uF. I found it on-line, Page 165, here:

http://www.parts-express.com/catalog/20 ... 165/zoomed

Closest standard values of 1.2 or 1.3 mH, and 20 uF would be good, the values can be +/- 5%, or even 10%, as this is within most of the components' tolerances.

For the cap, it is OK to parallel common values, like 1 uF with 0.22uF or 0.33 uF, in order to get the closest to correct value.
Don't try this with the inductors, as some rather strange and undesirable things can, and will happen...

Three-way, 12dB/Octave LC crossovers get quite a bit more complicated, as they have low pass, mid-pass (band-pass), and high pass sections.

There are pre-assembled 2-Way and 3-Way crossovers, on page 166 (click the right side arrow on the displayed page 165)

or, http://www.parts-express.com/catalog/20 ... 166/zoomed

Yeah, the 2013 prices are about 20-25% higher than they were, in the 2007 catalog

HTH

/ed B

thanks...this is very helpful. I had a feeling it was 4.0 but since it only had the dash and not 'mfd' or 'uf'...I wasn't sure. What do you think about using a metalized film capacitor of that value as opposed to the electrolytic? Is it worth it?

Metalized film would be good, IIRC Solen, Dayton, etc, make these in 100VDC ratings, for x-over usage, the larger and more
costly 400 or 600Vratings are not needed.

/ed B