Tapped Chokes

[speakerdave]

Anyone building two-way speakers using old drivers and horns may be interested in this information:

Some Tapped Inductors available at JBL Pro on Misc Parts List

Crossover, mH, Part #, Price $

JBL 3110 800 Hz, 2.14, 12883, 35


JBL 3115 500 Hz, 3.85, 10356, 57.25


JBL 3110A 800 Hz for CD horn, 3.33, 62627, 57.63??????????

JBL 3115A 500 Hz for CD horn, 5.1, 62626, 56.65


JBL 3120A 1200 Hz for CD horn, 2.5, 62628, 54.97

These part numbers are taken from the schematics. Not all of the inductors are listed as "tapped" but the prices would suggest they are. The question marks by the information for the 3110A signify that the number is not on the schematic available. The inductor is the correct size and the price fits. The 3110A schematic is not posted at JBL (actually it is if it's the same as the one for the 4660, which I think it is), but Giskard has posted it here:http://www.audioheritage.org/vbullet...ighlight=3110a

These crossovers are meant for PA use and may not really be suitable for use in the livingroom. Anyway, there seems to have been a lot of interest in these crossovers lately, and the prices on ebay are high. Notice, though, that if you buy a pair of these inductors you will in all but one case begin by spending more than $100 on just them.

David

P.S. Sorry for the lack of chart format, but my formatting was lost in the process of posting.

Additionally, there are a few other inductors that are listed as tapped or are priced commensurately, but I don't know what crossovers they are for. If anyone is able to find a corresponding part number in an interesting crossover schematic, please post it here.

David

[4313B]

Those prices are high. Tap your own coils. Use air cores. See how they work.

http://www.colomar.com/Shavano/inductor_info.html

http://home.new.rr.com/trumpetb/audio/chokejs.html

[spkrman57]

Those prices are high. Tap your own coils. Use air cores. See how they work.

http://www.colomar.com/Shavano/inductor_info.html

http://home.new.rr.com/trumpetb/audio/chokejs.html

All you need is the wire and some forms to make coils for a fraction of the cost of commercially built units.

I would recommend you buy a LCR meter. Parts Express has several for under $50.00(I think mine cost $35.00 last year) and they are invaluable for checking caps and coils to ensure the values are within tolerance.

I discard any caps that are more than 10% off their marked value as they are most likely leaky/bad.

Ron

[speakerdave]

I would recommend you buy a LCR meter. Parts Express has several for under $50.00(I think mine cost $35.00 last year) and they are invaluable for checking caps and coils to ensure the values are within tolerance.

OK

[4313B]

I think Rod also has another DIY inductor site link in his Passive Network article but I could be wrong.

***

Yep. Barry's Place -

http://sound.westhost.com/lr-passive.htm#8.0