Vintage A7 Repair - Horns Won't Work

[freemone233]

I copped a vintage (circa 1969) pair of A7's this weekend. The boxes had N501-8A Xovers that I replaced with N801-8A Xovers that came with the deal (also vintage). After wiring everything up and hooking them up to my Onkyo M-508/P-308 amp, I get good sound from the LF drivers but nothing from the HF horns. The seller assures me that they worked two years ago when he last listened to them BUT that was with the 501-8A Xovers and not these.

I've checked wiring and everything looks OK. This is m first time trying anything like this so any talk of testing, meters, etc. has to be VERY simplistic. I am appealing for help. THANK YOU!

Curtis

[Don Mascali]

Where are you located. I'm in Haymarket. We could work something out if you are close...

[freemone233]

I'm located in Richmond. I pulled a horn from one box (per recommendation from another forum) and hooked it directly to the amp outputs. There was NO sound and, according to the cited source, this suggests a blown diaphragm. I plan on running the test with the other horn, as well as the first horn, tomorrow. The preliminary plan is, IF there is no sound, they go to the local vintage repair shop for diaphragm replacement.

What did you have in mind? I'm open to suggestions and would accommodate you in any appropriate way to assist me with getting these bad boys up and fully running. Thank you very much.

Curtis

[Don Mascali]

I thought that if you were close by, I could come over and help you out.

It sounds like you are on the right track, I will IM my phone number and you can give me a call.

[Beowulf57]

You can also borrow a simple digital multimeter and check the DC resistance of the voice coils: infinite or zero resistance = blown or shorted voice coil.