Crossing over from dipole to monopole speakers

[brombo]

I have a Carver Amazing loudspeaker. The planar tweeters are going bad. I wish to refurbish (at reasonable cost) the speakers and donate them to the Montgomery College Planetarium which needs a decent sound system. I am thinking of the following for refurbishment. Replace each planar tweeter with an vertical array of 10 Fountek FR58EX 2" Neodymium Full Range Speaker Drivers -

http://www.parts-express.com/fountek-fr ... r--296-725

Bi-amplify the midrange/tweeter array and original Carver woofer section using a miniDSP 2x4 so room correction can be applied. The crossover would still be at 150Hz. The question is, is there a problem because the Carver woofers are dipoles and the new tweeter array would be a sealed box. What speaker design tools are you guys using these days. Show me the appropriate software and I could simulate the midrange/tweeter array in both sealed box and dipole configuration to see if the excursion gets to be too big and what sort of spl could be produced.

In general at low crossover frequencies does it matter if one speaker is a dipole and the other speaker a monopole.

[HAL]

Do yours have the BG RD75 style planar tweeters?

[brombo]

All it says in the service manual is Carver P/N 601-00451-00 Ribbon 30-inch. It is the first version of the speaker (Carver Amazing Loudspeaker) not the Silver or Platinum editions.

[HAL]

Like these with the 2 - 30" planar tweeters per side?

Attachments

[brombo]

Also Parts-Express says the BG RD75 is no longer available, period!

[brombo]

Yes those are my speakers.

[HAL]

Here is a guy that repairs the original Carver tweeters.

http://www.ebay.com/itm/CARVER-AMAZING- ... 1519647889

Those are not the BG RD75's.

[ratbagp]

Before you go to all the trouble of refurbishing, have you checked with the appropriate people at the College about having them installed? I suspect you would need to talk to the Instructional Technology people in the Office of Information Technology.

I used to work there in OIT for a while before retirement.

ray

[brombo]

I know the person who runs the planetarium and help him out all the time (on some Fridays we have group of physicists/astronomers/mathematicians doing group study of quantum mechanics and geometric algebra in the planetarium) so he an I together have a lot of flexibility in what we can do there equipment wise. They just had a new Spitz digital projector installed by Spitz, but Spitz went cheap on the sound system and it sounds terrible. It is just 5 Peavy PA speakers and a Behringer subwoofer.

I will consider the repair option. Do you have a good way of testing the planar array independent of the existing crossover. I could be lucky and the problem is not the planar array but the crossover.

[HAL]

I do have a Pocket CLIO measurement system and mic that can be used with a Windows 10 machine I setup for it. It can test both the crossover output at the drivers and the acoustic output of the speakers with the mic.

Probably first is to check the DC resistance of all 4 elements to see if they are all working and not open circuit. Just use an ohm meter across each of the elements.