Are 16 Ohm drivers preferred for 3-way system?

[David24x7]

I'm looking to build some new speakers using a compression driver for mid-range (like LE-175, LE-85 or 2420) and tweeter (like 077 or 2405). I've noticed that most 2405 tweeters on ebay are 16 Ohms. Is that what I want or doesn't it matter?

The reason I ask is that I already have a couple of LE-175 and an LE-85 in 8 Ohms. It would be great to be able to mix and match with new tweeters but I haven't seen any in 8 ohms. I know that I'm not supposed to mix 16 ohm and 8 ohm drivers in the same system though I think I recently saw JBL 4333 specs with 8 ohm woofer and 16 ohm mids and highs. Does that make sense?

Would love some advice on what I should be shopping for. Would you recommend that I keep looking for some 8 ohms super-tweeters or should I go with 16 ohms and find some new mid-range drivers while I'm at it?

Thanks for sharing!

[grumpy]

2405 or 077? they are what they are, regardless of the label.

mid? depends on what you want to do. Stock, 16 ohm LE175 and LE85 measure
lower at DC (ohm meter), so unless you've replaced the diaphragms, they're 16 ohms
(more or less) in their intended bandwidth use.

8 ohm woofer and 16(ish) ohm uppers? Done all the time.

If you want to reproduce an L300 or 4333 type system. Stick to stock rated
parts and existing crossover designs. Or go get an EE degree ;)

[badman]

I'd take 16 ohms over 8 ohms and a pad anyday- that's the key reason to use higher impedance drivers, is to avoid wasteful, sound quality-robbing padding

[David24x7]

2405 or 077? they are what they are, regardless of the label.

mid? depends on what you want to do. Stock, 16 ohm LE175 and LE85 measure
lower at DC (ohm meter), so unless you've replaced the diaphragms, they're 16 ohms
(more or less) in their intended bandwidth use.

8 ohm woofer and 16(ish) ohm uppers? Done all the time.

If you want to reproduce an L300 or 4333 type system. Stick to stock rated
parts and existing crossover designs. Or go get an EE degree ;)

Thx Grumpy. So if I can mix, 8 ohm woofers and 16 ohm uppers, then can I also mix an 8 ohm mid (like le85) with a 16 ohm hf (like 2405)?

I'll take a closer look at the 4333 specs but I think that they call for 16 ohm uppers.

[grumpy]

Well. The LE85 is not an 8 ohm driver (as I mentioned, it may -measure- that way with an ohm meter,
which only measures the DC value), and the 2405 is more like a 12 ohm driver, but whatever.

Yes, you can mix driver nominal impedances willy nilly, but changes to the crossover will be required...
Which is why I suggested you stick to a stock recipe of drivers and crossovers, where this mix of
impedance, sensitivity, etc... has been sorted out for you. Sticking to a similar enclosure volume
and tuning (port size and length) is also a good idea.

If someone has put in an actual 8 ohm diaphragm into the LE85 driver, you might want to consider
looking up systems that used say the 2425H driver as a component so the associated crossover will be at
least in the ballpark.

[Mr. Widget]

Thx Grumpy. So if I can mix, 8 ohm woofers and 16 ohm uppers, then can I also mix an 8 ohm mid (like le85) with a 16 ohm hf (like 2405)?

I'll take a closer look at the 4333 specs but I think that they call for 16 ohm uppers.Grumpy wasn't absolutely explicit since it has been stated over and over on this forum over the years, but due to idiosyncrasies within JBL the LE85, 077, 2405, and a handful of other drivers have been produced with both 8 ohm and 16 ohm labels. As long as they haven't been modified, all LE 85s have the same impedance regardless of the foilcal on the rear. All 2405s and 077s are also the same. When the label calls out an "A" or "B" variant or an "H" or "J" variant then the impedance is different.


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[Mr. Widget]

Well....I was typing while you posted this... But I'll leave mine for a bit of additional "clarity". :D


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[David24x7]

Grumpy wasn't absolutely explicit since it has been stated over and over on this forum over the years, but due to idiosyncrasies within JBL the LE85, 077, 2405, and a handful of other drivers have been produced with both 8 ohm and 16 ohm labels. As long as they haven't been modified, all LE 85s have the same impedance regardless of the foilcal on the rear. All 2405s and 077s are also the same. When the label calls out an "A" or "B" variant or an "H" or "J" variant then the impedance is different.

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OK. That makes me feel better. I was just taking a pic of the label on my LE85 labeled 8 ohm. If they are all the same impedance, it sure makes it easier to shop without worrying that I'm paying $100's for the wrong driver. BTW - is the same true for LE175?

[Mr. Widget]

OK. That makes me feel better. I was just taking a pic of the label on my LE85 labeled 8 ohm. If they are all the same impedance, it sure makes it easier to shop without worrying that I'm paying $100's for the wrong driver. BTW - is the same true for LE175?Yes, they are also nominally 16 ohms. The "easy" way to verify is to look up the driver's diaphragm on the "goes into" (http://www.jblproservice.com/pdf/Goes%20Into%20List/Goes%20Into%20List.pdf) list.


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