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beto
10-01-2005, 10:13 AM
Hi,
I have the oportunity to get a pair of Altec 802 D drivers + horn but the 16 Ohms model. On the other hand I will buy a pair of JBL2226H 8 Ohms woofers to build a speaker system.
My answer is, can I modify the Altec 802D impedance to match the 8 Ohms JBL speakers? If yes, this mod can degrade the sound, in others words is a better idea to wait to get the 8 Ohms version? (is very hard to find a good pair of this great HI F drivers and this is the first that I can get here)
Thank you in advance,
Beto

edgewound
10-01-2005, 10:19 AM
Hi,
I have the oportunity to get a pair of Altec 802 D drivers + horn but the 16 Ohms model. On the other hand I will buy a pair of JBL2226H 8 Ohms woofers to build a speaker system.
My answer is, can I modify the Altec 802D impedance to match the 8 Ohms JBL speakers? If yes, this mod can degrade the sound, in others words is a better idea to wait to get the 8 Ohms version? (is very hard to find a good pair of this great HI F drivers and this is the first that I can get here)
Thank you in advance,
Beto

You don't need to change the HF driver to 16 ohms. Your crossover network should be designed for a 16 ohm HF driver, and it's a closer match to the sensitivity of the 2226H. Many JBL and Altec systems used a 16 ohm HF driver with an 8 ohm LF driver.

beto
10-01-2005, 11:37 AM
Thanks edgewound,
actually, I have to match this new speaker system to 8 Ohms because this is the amp impedance (Audio Note Kit 1, 300B SET). So, all I have to do is modify the network, to get the 16 Ohms Altec and the 8 Ohms JBL working together with an 8 OHms SET amp. Is that posible without detail, soundtage and dynamics loss?
Thank you again.
Regards,
beto

Tom Loizeaux
10-01-2005, 06:06 PM
Usually the HF driver is much more efficient then the cone speakers. This usually means putting an L pad or resistor on the HF driver. If you put a 16 ohm, 20 watt resistor in parallel with the 16 ohm 802 compression driver, you'll have an 8 ohm HF unit. Then your crossover or cap value can be computed as if it were an 8 ohm unit. You'll "waste" some power, but that usually isn't a factor. The response of the 802 should not be affected by this paralled resistor.

Tom

spkrman57
10-02-2005, 05:43 AM
Repeated info for your benefit:

Since you are using a Pi crossover design set up for 8 ohms with a 16 ohm compression driver, you can just use the 15 ohm parallel shunt off the crossover, then a 30 ohm series resistor from there to the 802 paralleled with a .47 ufd cap (HF compensation).

I have done this in the past and be cause of the 15 and 30 ohm resistor loading on the crossover the 16 ohm 802 will slide right in.

I have also used the 16 ohm 2226J and changed the coil from .7 mh to 1.4(or in my case decided on 2 mh for a better blend to the HF section).


I hope this helps you out, I noticed you have posted this question on various forums!

Ron

beto
10-03-2005, 06:41 AM
Thank you very much spkrman57!
Regards,
Beto