HI.

I would like to use a pair of old  Altec 288b  drivers on Altec 805 horns in a live performance situation.

I notice that the drivers are 24 ohm impedance. what amp sould I use? I would like to use a modern amp, if i wire these in parallel mono I will be at 12 ohms. the amps I have are rated for 8 ohms. Also these are rated at 40 watts each, so all of my amps may be too large. I plan on using a digital crossover from 500HZ to 10,000HZ. and  one side of an an EV p1200 amp  I think the drivers had crossovers at one time , but I don't have them.  just wanted to see if anyone was already doing this, and which amps were being used.

Thanks

Dear Bob;

     You can use the drivers in parallel mono with your EV amp on one side. But be carefull not to drive them to hard. You might want to use a compressor-limiter on that amp out to protect your hi drivers.

     Also I would cross them over on the low side no lower than 800 hz to 1 Khz,below 800 that diaphgram is working.

     Good luck Joey B KP600

Thanks so much I will cross them over at 1k. Thanks again.

I need a pair of diaphragms for the 288b. I have read that the 288b needs to be modified to accept a modern replacement diaphragm. Do you guys know of a drop in replacement? or what is the actual modification? I also have a set of EV DH1A Drivers I could use if i had an adaptor from the ALTEC 3 bolt pattern to the EV 4 bolt pattern. I just want them to work in a modern application where they could be easily replaced in the field if needed. Any suggestions? I have done a little research, but I would like a really quick and dependable fix. I just need the vintage look of the ALTEC horns with a modern performance for this application.

 

Hi Bobby;

    I replied to your post with info on the diaphragms from my e mail. Let me know if you did not recieve it.

 

    Thanks Joey B KP600

Hi Bobby;

     Sorry you did not get the E-mail, I tried to do it from my E-mail reply. I guess that does not work, so I will respond from the Forum from now on !!

     Original ALTEC diaphragms retail for $ 140.00 ea. I can sell them to you for $ 125.00 ea. If you wanted to go with a very high quality aftemarket diaphragm I could sell them to you for $ 65.00 each. We replace diaphragms all the time in these and many types of drivers because they sound as good as the original, they are newer technology and cost less than half the money. They should go right in. If you have neve done a diaph replacement , take it to someone who is qualified or send them to me. The gap MUST BE CLEAN !! I can also check for rubs after replacement and do a sine sweep test to insure the driver is ready to go.

     As for the adaptors, I myself do not know of any, although that does not mean that they are not produced.

     If you need help respond to my home E-mail at jophise@comcast.net and I will get you going.

     Good luck JoeyB KP600